TAJ: Regional Power Transmission Project...1.0 01 August 2016 John Cook Peter Graham 2.0 30 March...

Consultant’s Report

Project Number: 43150-022 Grant Number: 0213 May 2019

TAJ: Regional Power Transmission Project This report does not necessarily reflect the views of ADB or the Government concerned, and neither the ADB nor the Government shall be held liable for its contents.

• SUBMITTED BY:

• IN ASSOCIATION WITH:

ADB GRANT NO: 0213 -TAJ

July 2018

Tajikistan

GRID CODE 16 July 2018

REGIONAL POWER TRANSMISSION PROJECT | SECTOR OPERATIONAL PERFORMANCE IMPROVEMENT |

TAJIKISTAN GRID CODE 16 JULY 2018

TAJIKISTAN: REGIONAL POWER TRANSMISSION PROJECT |

SECTOR OPERATIONAL PERFORMANCE IMPROVEMENT

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DOCUMENT CONTROL AND VERIFICATION SHEET

Job Title: Regional Power Transmission Project – Sector Operational Performance Improvement

Contract No: ADB Grant No: 0213-TAJ

Document Name: Grid Code (16 July 2018)

Document History:

Version Date Prepared Checked Approved

1.0 01 August 2016 John Cook Peter Graham

2.0 30 March 2017 John Cook Eric Harrison

3.0 26 April 2018 John Cook

4.0 16 July 2018 John Cook

http://upload.wikimedia.org/wikipedia/commons/a/af/Coat_of_arms_of_Tajikistan.svg




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1. Table of Contents

1. OBJECTIVES OF GRID CODE .................................................................................................................... 6

1.1. INTRODUCTION ............................................................................................................................................... 6 1.2. AUTHORITY ..................................................................................................................................................... 6 1.3. APPLICATION OF GRID CODE ......................................................................................................................... 6 1.4. TAJIKISTAN TRANSMISSION SYSTEM OPERATOR .......................................................................................... 7 1.5. OTHER ACTS, INDUSTRY CODES AND REGULATIONS ................................................................................... 8

2. SERVICE STANDARDS ................................................................................................................................ 9

2.1. QUALITY OF SUPPLY AND SYSTEM RELIABILITY.............................................................................................. 9 2.2. TRANSMISSION SYSTEM STANDARDS ............................................................................................................. 9 2.3. REPORTING STANDARDS ............................................................................................................................... 9 2.4. SPECIFIC RELIABILITY STANDARDS ................................................................................................................ 9 2.5. SERVICE CATEGORIES ................................................................................................................................... 9 2.6. OBLIGATION TO RESTORE CAPACITY ............................................................................................................. 9 2.7. SPARE TRANSFORMERS ............................................................................................................................... 10 2.8. EMERGENCY TRANSFORMER REPLACEMENT PLAN .................................................................................... 10 2.9. RATING OF TRANSMISSION LINES AND TRANSFORMERS .............................................................................. 10

3. PLANNING CODE ....................................................................................................................................... 11

3.1. INTRODUCTION ............................................................................................................................................. 11 3.2. PLANNING CODE OBJECTIVES ..................................................................................................................... 11 3.3. TAJIKISTAN TRANSMISSION SYSTEM FORWARD STATEMENT ..................................................................... 11 3.4. TRANSMISSION SYSTEM USERS AND PROSPECTIVE USERS ARE: .......................................................... 11 3.5. CONNECTION CONTRACT TECHNICAL REQUIREMENTS .............................................................................. 11 3.6. DEVELOPMENT ............................................................................................................................................. 11 3.7. STRENGTHENING OF THE TRANSMISSION SYSTEM ...................................................................................... 12 3.8. TIMESCALE ................................................................................................................................................... 12 3.9. PLANNING INFORMATION REQUIREMENTS ................................................................................................... 12 3.9.1. SUBMISSIONS TO SYSTEM OPERATOR BY USERS ON AN ANNUAL BASIS. .............................................. 12 3.9.2. INFORMATION PROVIDED TO USERS BY THE SYSTEM OPERATOR ......................................................... 13 3.10. STANDARD PLANNING DATA .................................................................................................................... 13 3.10.1. USER'S SYSTEM LAYOUT ......................................................................................................................... 13 3.10.2. SYSTEM PARAMETERS............................................................................................................................. 14 3.10.3. TRANSFORMERS ...................................................................................................................................... 14 3.10.4. CIRCUIT BREAKERS ................................................................................................................................. 14 3.10.5. SUBSTATION INFRASTRUCTURE. ............................................................................................................. 14 3.10.6. SHORT CIRCUIT CONTRIBUTION TO TAJIKISTAN TRANSMISSION SYSTEM ............................................. 15 3.11. TAJIKISTAN TRANSMISSION SYSTEM NETWORK INFORMATION. ............................................................. 15 3.11.1. DATA FROM DISTRIBUTION AND NON-EMBEDDED CUSTOMERS............................................................. 15 3.12. GENERATING UNIT AND DC CONVERTER DATA ..................................................................................... 15 3.12.1. GENERAL DATA ........................................................................................................................................ 15 3.12.2. DIRECTLY CONNECTED............................................................................................................................ 15 3.12.3. DC CONVERTER STATIONS. .................................................................................................................... 15 3.12.4. BUSBAR ARRANGEMENTS ........................................................................................................................ 16 3.12.5. RATED PARAMETERS DATA ..................................................................................................................... 16 3.13. DEMAND AND ACTIVE ENERGY DATA ...................................................................................................... 16 3.13.1. USER SYSTEM DEMAND (ACTIVE POWER) AND ACTIVE ENERGY DATA ................................................ 16 3.14. PREPARATION OF ANNUAL FORECAST DEMAND STATEMENT. ............................................................... 17 3.14.1. PROTECTION SYSTEM DATA .................................................................................................................... 17 3.15. COMPLEX CONNECTIONS ........................................................................................................................ 17

4. DESIGN AND TECHNICAL REQUIREMENTS ......................................................................................... 18





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4.1. TECHNICAL REQUIREMENTS ......................................................................................................................... 18 4.2. GENERAL REQUIREMENTS ........................................................................................................................... 18 4.3. SYSTEM COMPATIBILITY ............................................................................................................................... 18 4.4. DESIGN STANDARDS..................................................................................................................................... 18 4.5. PROTECTION STANDARDS ........................................................................................................................... 18 4.6. COMMUNICATIONS........................................................................................................................................ 20 4.7. USER SYSTEM MODIFICATIONS .................................................................................................................... 21 4.8. TRANSMISSION MAINTENANCE AND TEST REQUIREMENTS ........................................................................ 21 4.9. USER MAINTENANCE AND TEST REQUIREMENTS ........................................................................................ 21 4.10. FAULTS OR INCIPIENT FAULTS ................................................................................................................. 21

5. OUTAGES AND MAINTENANCE .............................................................................................................. 22

5.1. INTERRUPTIONS OR RESTRICTIONS TO TRANSMISSION SERVICES............................................................. 22 5.2. NON-SCHEDULED OUTAGES .................................................................................................................. 22 5.3. OUTAGE PLANNING COORDINATION ............................................................................................................ 22 5.4. GENERATION OUTAGE PLANNING................................................................................................................ 22 5.5. TRANSMISSION OUTAGE PLANNING............................................................................................................. 23

6. METERING ................................................................................................................................................... 25

6.1. PRINCIPLES .................................................................................................................................................. 25 6.2. LOCATION OF METERING POINTS ................................................................................................................ 25 6.3. APPLICATION ................................................................................................................................................ 25 6.4. METERING REQUIREMENTS ......................................................................................................................... 25 6.5. METERING INSTALLATIONS .......................................................................................................................... 26 6.6. TESTING AUTHORITY .................................................................................................................................... 26 6.7. STANDARDS .................................................................................................................................................. 26 6.8. METER PERFORMANCE REQUIREMENTS ..................................................................................................... 27 6.9. METERING DATA COLLECTION ..................................................................................................................... 27 6.10. SETTLEMENT OF ACCOUNTS ................................................................................................................... 27 6.11. ACCESS .................................................................................................................................................... 27 6.12. REVENUE AND TAMPER PROTECTION ..................................................................................................... 27 6.13. METER INSTALLATION TESTING ............................................................................................................... 27

7. ACCESS TO SITES, OPERATIONS AND AUTHORISATIONS ............................................................. 28

7.1. RIGHTS OF ACCESS ...................................................................................................................................... 28 7.2. COMMON FACILITIES .................................................................................................................................... 28 7.3. SITE OPERATIONS, GENERATION, TRANSMISSION AND DISTRIBUTION SUBSTATIONS .............................. 28 7.4. TRANSMISSION AND DISTRIBUTION SUBSTATION SITES ............................................................................. 28 7.5. SYSTEM OPERATIONS AND MAINTENANCE. ................................................................................................ 28 7.6. SYSTEM STABILITY. ...................................................................................................................................... 29 7.7. PERSONNEL AUTHORISATIONS TO ENTER A SITE. ...................................................................................... 29 7.8. PERSONNEL AUTHORISATIONS FOR OPERATIONS AND MAINTENANCE. ..................................................... 29

8. GENERATION DISPATCH ......................................................................................................................... 30

8.1. OBJECTIVES ................................................................................................................................................. 30 8.2. SCOPE .......................................................................................................................................................... 30 8.3. GENERATOR AVAILABILITY DECLARATION .................................................................................................... 30 8.4. GENERATION SCHEDULING AND DISPATCH PARAMETERS ........................................................................... 31 8.5. LEAST COST OPERATION .............................................................................................................................. 31 8.6. CONSTRAINED AND UNCONSTRAINED SCHEDULES ...................................................................................... 31 8.7. COMPLETION OF SCHEDULING ..................................................................................................................... 32 8.8. SYNCHRONISING AND DE-SYNCHRONISING ................................................................................................. 32 8.9. OTHER RELEVANT GENERATION DATA ........................................................................................................ 33 8.10. EMERGENCY GENERATION REQUIREMENTS ........................................................................................... 33 8.11. DISTRIBUTION NETWORK DATA ............................................................................................................... 33 8.12. DATA VALIDITY CHECKING ....................................................................................................................... 33





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8.13. DEMAND REDUCTION DATA ..................................................................................................................... 34 8.14. AVAILABILITY DECLARATION .................................................................................................................... 34 8.15. DISPATCH INSTRUCTION PROCEDURES ................................................................................................... 34 8.16. UPDATING AND REVISING THE GENERATION SCHEDULE.......................................................................... 35 8.17. DISPATCH INSTRUCTIONS, ISSUE AND VARIATION ................................................................................... 35 8.18. SCOPE OF DISPATCH INSTRUCTIONS FOR GENERATOR UNITS ................................................................ 35 8.19. DISPATCH REQUIREMENTS ...................................................................................................................... 37 02.8. CHANGES TO DESPATCH INSTRUCTIONS ................................................................................................ 37 8.21. REPORTING .............................................................................................................................................. 39 8.22. EMERGENCY ASSISTANCE INSTRUCTIONS ............................................................................................... 39 8.23. DISPATCH INSTRUCTIONS FOR LOADING AND SYNCHRONISING .............................................................. 40 8.24. DISPATCHING A SYNCHRONISED GENERATING UNIT TO INCREASE OR DECREASE OUTPUT ................... 40 8.25. GENERATOR UNIT SYNCHRONISING ......................................................................................................... 40 8.26. GENERATOR UNIT DE-SYNCHRONISING ................................................................................................... 40 8.27. DISPATCH INSTRUCTIONS – LOADING AND SYNCHRONISING................................................................... 41 8.28. DISPATCH INSTRUCTIONS, OTHER FACTORS ........................................................................................... 41 8.29. FREQUENCY AND INTERCONNECTOR TRANSFER CONTROL .................................................................... 41 8.30. PLANT OPERATING BELOW MINIMUM GENERATION .................................................................................. 43 8.31. GENERAL ISSUES ..................................................................................................................................... 43 8.32. FREQUENCY AND TIME CONTROL............................................................................................................. 43 8.33. INTERCONNECTOR TRANSFER CONTROL – EXTERNALLY INTERCONNECTED PARTY .............................. 44

9. EMERGENCIES AND SAFETY .................................................................................................................. 45

9.1. EMERGENCY DISCONNECTION ..................................................................................................................... 45 9.2. EXERCISING EMERGENCY DISCONNECTION RIGHTS .................................................................................. 45 9.3. HEALTH AND SAFETY .................................................................................................................................... 45 9.4. EMERGENCY PROVISIONS OF OTHER ACTS ................................................................................................. 45 9.5. EMERGENCY OPERATIONS ......................................................................................................................... 45 9.6. OBJECTIVES OF EMERGENCY OPERATIONS ................................................................................................ 46 9.7. DETERMINATION OF EMERGENCY CONDITIONS ................................................................................... 46 9.8. GRID SYSTEM RESTORATION PLAN ........................................................................................................ 46 9.9. AUDIT TO ENSURE RESTORATION OF THE SYSTEM AND ALL DEMAND IS CONNECTED ............................... 47 9.10. RESTORATION PROCEDURES ............................................................................................................. 47 9.11. SWITCHING GUIDELINES USED FOR SYSTEM RESTORATION: .................................................................. 47 9.12. DEMAND RESTORATION ........................................................................................................................ 47 9.13. RE-ENERGISATION PROCEDURES ............................................................................................................ 48 9.14. DEALING WITH SYSTEM SPLITS .............................................................................................................. 48 9.15. GRID SYSTEM RESTORATION PLAN FAMILIARISATION. ...................................................................... 48 9.16. RECOVERY PROCEDURES FROM ABNORMAL OPERATING CONDITIONS...................................... 49 9.17. LOSS OF LOAD DISPATCH CENTRE OR PRIMARY CONTROL CENTRE .................................................... 49 9.18. PRIMARY ENERGY SUPPLY EMERGENCY .............................................................................................. 49

10. DEFINITIONS ............................................................................................................................................... 50





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1. OBJECTIVES OF GRID CODE

1.1. INTRODUCTION

For countries where power systems have, over a number of years, developed completely separate generation, transmission and distribution entities, generally with market operations, sophisticated grid codes have of necessity been developed to match the increasing complexities of market operations. As BT has only operated as an integrated utility, without full market operation, these initial grid code requirements concentrate on formalising the working relationships between the separate entities, generation, transmission and distribution. As the Tajikistan power system develops with increasing commercial considerations and market operations, the grid code will, as in other countries, need to be developed in step with changing conditions.

With the restructuring of BT and concomitant separation into generation, transmission and distribution entities, there is a necessity to formally define the relationships and responsibilities of each entity. Implicit relationships and responsibilities exist between the generation, transmission and distribution sections of BT. As separate entities, these implicit relationships and responsibilities will need to be formally documented. As the separate entities mature and market operations are introduced, the formal documentation will require development as conditions change.

Existing comprehensive operational documentation currently describes and delineates responsibilities for BT as an integrated utility. This documentation is presently not collated in a manner suitable for separate entities and this will need to be addressed during the transition from the existing operational structure to operating as separate entities. Clearly the existing operational documentation authority will continue until appropriate new documentation is developed.

This grid code indicates principles and procedures relating to the technical relationships between Transmission and Users of the Tajikistan Electricity Transmission system. Users of the Tajikistan Electricity Transmission system include Generation, Distribution, Independent Power Producers, Large Power Customers and International Connections.

The grid code is intended to define the initial and prospective requirements for developing, maintaining, operating an efficient, secure, safe and coordinated transmission system.

Initially the present safety rules will of necessity need to remain in force. Based on the existing safety rules, each user shall develop safety rules appropriate to their particular entity.

Recognising the recent adequacy of energy during the winter period, the required service standards were fulfilled. Until a sufficient margin of generation capacity and associated potential energy capacity becomes available over the long term, the required service standards may occasionally not be satisfied during the winter period.

Holders of licences to generate, transmit or distribute shall be obliged, in writing, to accept and comply with the Grid code of Tajikistan.

Definitions of acronyms and technical terms are provided in Section 10 of this document.

1.2. AUTHORITY

This grid code is empowered by the Tajikistan Ministry of Energy and Water Resources (MoEWR) and the Antimonopoly Service (AMS).

An Independent Regulator for Tajikistan will be established in the future. The Grid code will become a responsibility of the Independent Regulator.

1.3. APPLICATION OF GRID CODE

This grid code specifies obligations of the Tajikistan Electricity Transmission entity in relation to the provision of transmission services and the reciprocal obligations of Users.





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Ge

ne

rators

Transmission System. 500kV, 220kV, 110kV

International Connections

System Operator and Dispatch

Directly Connected Customers

Distribution System.35kV and Below.

Including 110kV for Dushanbe.

Embedded Generation

Cu

stom

ersInternational Connections

GRID CODE Future Distribution Code

Transmission system Users and prospective Users are:

Generation entity and the constituent parts belonging to, or formerly belonging to BT.

CHP generation at Dushanbe1.

CHP generation at Dushanbe 2.

CHP generation at Yavan.

Generation owned by private investors or countries other than Tajikistan.

Prospective providers of generation.

Operators of power systems interconnected or prospectively connected with Tajikistan Electricity Transmission system.

Distribution entities and constituent parts belonging to, or formerly belonging to BT.

Large power consumers connected to the Tajikistan Electricity Transmission system, although not necessarily purchasers of electricity from transmission.

1.4. TAJIKISTAN TRANSMISSION SYSTEM OPERATOR

The Transmission System Operator (TSO) is the entity entrusted with managing the organisation of power generation and the subsequent transportation of electrical power at a national and regional level. In addition, the TSO is assigned the responsibility for optimising primary energy use to ensure adequate water resources are available throughout the year.

There are two components of transmission system operation, firstly there is transmission network operation and secondly the operation of generation and transmission systems. Transmission System Operator (TSO) as a Transmission Network Operator

Ensure reliable operation of the Republic of Tajikistan’s power grid.

Maintain an adequate transmission system over the long run.

Plan the transmission network utilising new investments, renewal and maintenance of existing network components so that the network is secure to operate and adequate transmission capacity is guaranteed.

Prepare development plans using data provided by system users and by utilising analysis and planning tools.

Secure technical compatibility with cross border connections.

Plan and expedite network expansions based on the requirements of users and potential users. Transmission System Operator (TSO) as a System Operator

Exercise operational control of generation for the grid system

Ensure reliable operation of the Republic of Tajikistan’s power grid2

Compile and disseminate generation dispatch schedules, taking into account all the financial and contractual aspects of available generation.





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Organise the energy balancing market in real time.

Manage the operational security of the power system and maintain the momentary balance between power supply and demand.

Define and manage generation reserve capacity.

Develop long term forecasting of power requirements

Interact with system operators of internationally connected grid systems to ensure stability of parallel operation and minimise inadvertent power flows.

Manage optimisation of primary energy use, with particular emphasis on ensuring the availability of sufficient water to generate electrical power over the winter period.

Safeguard and maintain adequacy of the transmission system over the long run.

Define technical requirements for the secure system operation.

Plan system protection measures to avoid system disturbances and system collapse.

To prevent system collapse, activate corrective actions without delay by use of automatic and manual arrangements, including automatic load shedding.

Prepare contingency plans for emergency generation to obviate total system collapse or potential national calamity

Ensure black start capability to provide a rapid system restoration in case of system collapse.

Manage a generation shortage situation with updated actions plans, including any agreements for disconnections.

Coordinate system outage maintenance and construction programmes.

Provide equal access conditions to the grid system for users and potential users.

Participate in wholesale commercial metering systems and settlements until the establishment of a market operator and meter operator.

Utilise, and disseminate to relevant parties, data obtained from SCADA and other automatic data acquisition systems.

Provide power control system services.

Effect financial regulation of power imbalances under the legislation of the Republic of Tajikistan.

1.5. OTHER ACTS, INDUSTRY CODES AND REGULATIONS

Not all aspects of Tajikistan Electricity Transmission entity’s obligations are regulated by this code2 Tajikistan Transmission entity’s obligations and some aspects of the relationships between Users may also be affected by:

Acts of Parliament and regulations made under those Acts of Parliament.

Government of Tajikistan decrees.

Contractual arrangements between Users.

Contractual arrangements between Tajikistan Electricity Transmission and Users.





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2. SERVICE STANDARDS

2.1. QUALITY OF SUPPLY AND SYSTEM RELIABILITY

Subject to the service standards specified in this section, Tajikistan Electricity Transmission entity must strive to plan, develop and operate the transmission network such that there will be no requirements to disconnect load under normal and reasonably anticipated operating conditions. Supply parameters pertaining to frequency and voltage shall be maintained according to GOST.

2.2. TRANSMISSION SYSTEM STANDARDS

The MoEWR or Government of Tajikistan authorised agencies, may issue service standards and procedures applicable to Tajikistan Electricity Transmission entity and with which Tajikistan Electricity Transmission entity must comply. Existing BT standards will apply until Tajikistan Electricity Transmission entity standards are specifically developed.

2.3. REPORTING STANDARDS

The Tajikistan Electricity Transmission entity must in accordance with any guidelines published for this purpose, or as directed by MoEWR or authorised Government of Tajikistan agencies, report on performance against applicable standards and procedures. Existing reporting formats shall be maintained until such time a new formats and schedules are agreed.

2.4. SPECIFIC RELIABILITY STANDARDS

The Tajikistan Electricity Transmission entity, in conjunction with the relevant users, shall plan and develop the transmission system such that each category of customer receives the service standards in accordance with 2.5

2.5. SERVICE CATEGORIES

Category Service Requirements

1

Customers of the first category are those where an interruption of power supply which may entail danger to human life, significant damage to the national economy, damage to expensive basic equipment, and breakdown of complex technological processes. The power supply must be provided from two independent sources. A break in the power supply is possible for the time of automatic restoration of supply from an alternative source.

2

Second category customers are those where an interruption of power supply may lead to mass shortage of products, to mass shutdown of machinery and industrial transport. The power supply must be provided from the two independent energy sources and a break in the power supply could be possible for the time necessary to switch over to an alternative source by duty personnel or emergency crew.

3 Third category customers are all others that do not fit the first and second category definitions. The interruption of power supply during the repair or replacement of damaged equipment should not exceed 1 day.

2.6. OBLIGATION TO RESTORE CAPACITY

After failure of a transmission line, transformer, network support arrangement, or critical system component, Tajikistan Electricity Transmission entity is obliged as soon as practicable, to restore the system in accordance with the service standards indicated in this section. Service categories shall be maintained until such time as the restoration standards are reconsidered. Tajikistan Transmission shall provide all practicable assistance to the distribution network restoration. With the system service standards obligations, Tajikistan Transmission shall consider:

Minimising the duration of an interruption arising from the initial failure.





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Minimising the possibility of a further interruption to supply resulting from a failure in another part of the system

2.7. SPARE TRANSFORMERS

Tajikistan Electricity Transmission entity must have sufficient and available transformers of suitable capacity to ensure the service standards shall be met.

2.8. EMERGENCY TRANSFORMER REPLACEMENT PLAN

Tajikistan Electricity Transmission entity must prepare and implement an Emergency Transformer Replacement Plan setting out the strategy for ensuring spare transformers are available to meet the reliability standards.

2.9. RATING OF TRANSMISSION LINES AND TRANSFORMERS

Tajikistan Electricity Transmission entity must, as required by the MoEWR or Government of Tajikistan authorised agencies, provide details of line and transformer ratings and how the ratings were derived. A change in rating policy shall be notified to MoEWR.





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3. PLANNING CODE

3.1. INTRODUCTION

The planning code specifies the basic technical and design criteria and procedures to be applied by transmission in the planning and development of the Tajikistan electricity transmission system (TTS) and to be taken into account by users in the planning and development of their own systems. It details information to be supplied by users and prospective users to the system operator and information to be supplied by transmission to users and prospective users.

3.2. PLANNING CODE OBJECTIVES

Ensure consultation between transmission and user in respect of proposed development on the User System which may affect performance of the TTS or affect the actual connection with the TTS.

For Users to provide information to Transmission so that planning and development of the TTS can be effected in accordance with the relevant Technical and Commercial requirements.

To facilitate contractual obligations of users and TTS.

To facilitate compliance with licence requirements.

For users to provide transmission with information to enable the facilitation of proposed connections and alterations to existing connections.

For transmission to provide users with technical information necessary to enable new connections.

For transmission to provide users with technical information about changes to the transmission system that may affect users.

3.3. TAJIKISTAN TRANSMISSION SYSTEM FORWARD STATEMENT

To enable the Tajikistan Transmission System annual forward Statement to be prepared, each User is required to submit to the Tajikistan Transmission System Operator information as indicated in this code. This information should include each of the five subsequent Years. When there is no change from previously submitted information, a User may submit a written statement that there has been no change.

3.4. TRANSMISSION SYSTEM USERS AND PROSPECTIVE USERS ARE:

Power Generation Stations, either belonging to or formerly belonging to BT.

Distribution entity formerly belonging to BT.

Generation owned by private investors.

Operators of power systems in neighbouring countries interconnected with TTS.

Large power consumers connected to the TTS, (although not purchasers of electricity from transmission.)

Prospective providers of generation.

Prospective large power consumers

3.5. CONNECTION CONTRACT TECHNICAL REQUIREMENTS

In addition to commercial information to be submitted with an application for connection or modification, technical information as detailed in the Planning Code and as indicated below is required. Description of the project including the plant and equipment.

Proposed project Completion Date

Relevant technical information as detailed in the Planning Code

Transmission entry Capacity.

Transmission exit capacity.

3.6. DEVELOPMENT

Development of the TTS, involving reinforcement or extension, will arise for a number of reasons including: Development on a User System already connected to the TTS

Increasing general system demand.

New generation connection.





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New Connection or the Modification of an existing Connection between a User System and the TTS;

Combined effect of developments by one or more Users.

3.7. STRENGTHENING OF THE TRANSMISSION SYSTEM

Strengthening or extension of the TTS may involve work at: A substation at a connection site where user's plant and/or apparatus is connected to the TTS

On transmission lines or other facilities which join that connection site

On transmission lines or other facilities at or between points remote from the connection site

3.8. TIMESCALE

The time required for the planning and development of the Tajikistan Electricity Transmission System will depend on: Nature and extent of the required work.

Necessary consents from statutory bodies, local authorities and Government of Tajikistan.

Complexity of the required work.

Outage availability commensurate with maintaining TTS security

3.9. PLANNING INFORMATION REQUIREMENTS

Planning information to be provided by Users to The System Operator and conversely is indicated below. 3.9.1. SUBMISSIONS TO SYSTEM OPERATOR BY USERS ON AN ANNUAL BASIS. Forecast demand data for the current and following 5 years.

Forecast available generation capacity for the current and following 5 years.

Generation maintenance program for current and following 5 years.

Distribution network maintenance program at transmission interface sites.

Distribution network forecast embedded generation capacity for current and following years.

Number of generating equipment and types of equipment;

Nominal (installed) capacity in megawatts;

Nominal voltage at the terminals (kv);

Rated power factor;

Available capacity by months of the year in megawatts;

Technological minimum of generating equipment, in megawatts;

Technological maximum of generating equipment, in megawatts;

Working scheme of the generator at the stator terminals of the power plant;

The expected operating mode (basic, average or peak load or standby plant) at each power plant and the

type of power plant, namely the steam, gas turbine, hydro, etc. .;

The forecast schedule of active power generation for individual power plants with direct connection to the

power grid. It is necessary to provide data on maximum and minimum energy consumption for peak days

at each connection point, normal energy consumption during the working day, and on Saturday and

Sunday at the connection point for each month of the year;

Detailed information on the capability of the power plant to work without connecting to an external power

source, as well as information about any changes of this capability.





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3.9.2. INFORMATION PROVIDED TO USERS BY THE SYSTEM OPERATOR

To enable Users to model their electrical networks, the System Operator will provide the following information to Users:

On an annual basis the system operator will provide users with transmission system fault level data and prospective changes to system fault levels.

Replenishment by a symmetrical three-phase short-circuit current during the fault;

Replenishment by a symmetrical three-phase short-circuit current after a significant deterioration of the supertransient fault current;

The internal zero resistance of the power source and the value of the reactive resistance at the connection point corresponding to the maximum replenishment;

The value of the voltage before the fault, used in calculating the maximum fault current;

The coefficient of the direct sequence x / r during the fault;

Resistance values of the negative sequence and the reactance of the electrical network at the connection point

The value of the corresponding full zero-sequence impedance;

Since for the electric network with 500 and 220 kv the equivalent will be calculated, the system operator shall provide the corresponding data about the transformer.

Any other relevant technical data necessary for users to model their systems.

Tajikistan electricity transmission system annual maintenance program.

3.10. STANDARD PLANNING DATA

Users, whether already directly connected through an existing Connection Point or requiring a direct connection shall provide Tajikistan Electricity Transmission System Operator with system data. Standard Planning Data shall be supplied to The System Operator by Users and Potential Users as indicated below. 3.10.1. USER'S SYSTEM LAYOUT

Each user with direct connection to the electrical network through the existing connection point annually provides the system operator with the following information about his system at the connection point:

Scheme for placing the user's system, a single-line scheme, including:

Bus layout;

The layout of the electrical circuit (air power lines, underground cable, transformers, etc.);

Phase scheme;

Earthing scheme;

Switching devices;

Operating voltage;

Device numbers and nomenclature (dispatching name)

Each user shall present data on the equivalent total conductance of his primary voltage system at normal frequency. This includes shunt reactors connected to cables that do not normally work separately from them;

Reactive power compensation installations:

Type of compensation (fixed or variable);

Capacitive and / or inductive nominal value or mode of operation in mvar;

Detailed information about the logic of any computerized control for determining operating characteristics;

Point of connection to the user's system - electrical placement and line voltage;

Influence of short-circuit currents on the electrical network:





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3.10.2. SYSTEM PARAMETERS For each circuit shown on the Single Line Diagram each User shall provide the following details relating to that part of its User System. Circuit Parameters: Rated voltage (kV) Operating voltage (kV)

Positive phase sequence reactance, Positive phase sequence resistance, Positive phase sequence susceptance

Zero phase sequence reactance (both self and mutual) Zero phase sequence resistance (both self and mutual) Zero phase sequence susceptance (both self and mutual)

3.10.3. TRANSFORMERS For each transformer shown on the Single Line Diagram, each User shall provide the following details: Rated MVA

Voltage Ratio

On-load tap-changer and off-circuit tap-changer"

Positive sequence reactance (max, min and nominal tap)

Positive sequence resistance (max, min and nominal tap)

Zero sequence reactance

Tap changer range

Tap change step size

Tap changer type: on load or off circuit

Impedance (if not directly earthed)

Number of windings;

Nominal value of mva for each winding;

Basic rated tapping voltage;

Full impedance of forward, reverse and zero sequence for each winding;

Group of connected windings;

Earthing scheme; Data on the tap changer:

Winding with taps - text diagram;

Range of tap change, step size;

Type of tap changer;

Tap-changing cycle duration. 3.10.4. CIRCUIT BREAKERS

Rated voltage (kV) Operating voltage (kV)

Rated 3-phase rms short-circuit breaking current, (kA) Rated 1-phase rms short-circuit breaking current, (kA) Rated 3-phase peak short-circuit making current, (kA) Rated 1-phase peak short-circuit making current, (kA) Rated rms continuous current (A)

DC time constant applied at testing of asymmetrical breaking abilities (secs) 3.10.5. SUBSTATION INFRASTRUCTURE.

For the substation infrastructure (including, but not limited to, switch disconnectors, disconnectors, current transformers, line traps, busbars.

Rated 3-phase rms short-circuit withstand current (kA)

Rated 1-phase rms short-circuit withstand current (kA).

Rated 3-phase short-circuit peak withstand current (kA)

Rated 1- phase short-circuit peak withstand current (kA)

Rated duration of short circuit withstand (secs)

Rated rms continuous current (A) A single value for the entire substation may be supplied, provided it represents the most restrictive item of current carrying apparatus.





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3.10.6. SHORT CIRCUIT CONTRIBUTION TO TAJIKISTAN TRANSMISSION SYSTEM

To allow the system operator to calculate fault currents, each user is required to provide data, calculated in accordance with industry practice. The data should be provided for the user's system with all generating units and dc converters synchronized to the user's system. Measurements made under appropriate system conditions may be used by the user to obtain the relevant data.

The System Operator may at any time specifically request for data to be provided for an alternative System condition, for example minimum plant., The User will, insofar as such request is reasonable, provide the information as soon as reasonably practicable following the request. Where prospective short-circuit currents on equipment owned, operated or managed by TTS are approaching the equipment rating and in TTS opinion more accurate calculations of the prospective short circuit currents are required, then The System Operator will request additional data.

3.11. TAJIKISTAN TRANSMISSION SYSTEM NETWORK INFORMATION.

The System Operator will provide Users with network information to enable short circuit calculations. The information will be provided on an annual basis or when proposed system changes are considered to effect Users’ networks or systems 3.11.1. DATA FROM DISTRIBUTION AND NON-EMBEDDED CUSTOMERS

Data from Generators and DC Converter Station owners is required to be provided for each node on the Single Line Diagram.

For each Generating Unit with one or more associated Unit Transformers, is required to provide values for the contribution of the Power Station Auxiliaries to the fault current flowing through the Unit Transformers.

Data for the fault infeeds through both Unit Transformers and Station Transformers shall be provided for the normal running arrangement when the maximum number of Generating Units are Synchronised to the System or when all the DC Converters at a DC Converter Station are transferring rated MW in either direction.

3.12. GENERATING UNIT AND DC CONVERTER DATA

3.12.1. GENERAL DATA

The point of connection to Tajikistan transmission system

Type of generating unit (synchronous generating unit, non-synchronous)

Generating unit, DC converter

In the case of a synchronous generating unit details of the exciter category, for example whether it is a rotating exciter or a static exciter or in the case of a non-synchronous generating unit the voltage control system.

Each generator shall supply the system operator with the primary source of energy in respect of each generating unit 3.12.2. DIRECTLY CONNECTED

Each Generator and DC Converter Station with an existing, or proposed, Power Station or DC Converter Station directly connected, or to be directly connected, to TTS shall provide the System Operator with current and forecast data relating to the Power Station or DC Converter Station. Information to be supplied by each User:

Registered capacity (MW)

Output usable (MW) on a monthly basis

Minimum generation (MW)

3.12.3. DC CONVERTER STATIONS.

The following additional items are only applicable to DC Converters at DC Converter Stations.





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Registered Import Capacity (MW); Import Usable (MW) on a monthly basis; Minimum Import Capacity (MW);

MW that may be absorbed by a DC Converter in excess of Registered Import

Capacity and the duration for which this is available; 3.12.4. BUSBAR ARRANGEMENTS

Where generating units and dc converters, are connected to the Tajikistan transmission system via a busbar arrangement which is or is expected to be operated in separate sections, the section of busbar to which each generating unit or DC converter is connected is to be identified in the submission. 3.12.5. RATED PARAMETERS DATA

The following information is required to facilitate an early assessment for connection by the System Operator.

For all Generating Units:

Rated MW

Short circuit ratio

Direct axis transient reactance

Inertia constant (for whole machine), MW secs/MVA

For each Synchronous Generating Unit step-up transformer: Rated MVA

Positive sequence reactance (at max, min and nominal tap);

For each DC Converter at a DC Converter Station:

DC Converter type, current/voltage.

Rated MW for import and export.

Return path arrangement

Remote AC connection arrangement

Rated MW

Rated terminal voltage

Inertia constant, (MW sec/MVA)

Rated DC current and voltage

3.13. DEMAND AND ACTIVE ENERGY DATA

Each user directly connected to the national electricity transmission system with demand shall provide Tajikistan electricity transmission system operator with historic, current and forecast demand data, Data shall be supplied by:

Each User in relation to Demand and Active Energy requirements on the User’s system

Each DC Converter Station owner in relation to Demand and Active Energy transferred

Imported electric energy to its DC Converter Station.

Demand of Power Stations directly connected to the Transmission System. 3.13.1. USER SYSTEM DEMAND (ACTIVE POWER) AND ACTIVE ENERGY DATA

Forecast daily demand (Active Power) profiles, as specified below, in respect of each User is required for:

Peak day on each of the users’ systems (as determined by the user) giving the numerical value of the maximum demand (active power) that in the user’s opinion could reasonably be imposed on the electricity transmission system;

Day of peak electricity transmission system demand (active power) as notified by Tajikistan electricity transmission system operator.

Day of minimum electricity transmission system demand (active power) as notified by Tajikistan electricity transmission system operator.

The total active energy used on each user system (summated over all grid supply points in each user system) in the previous year, both outturn and weather corrected, together with a prediction for the current financial year.





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All forecast Demand shall:

Include any User's System series reactive losses but exclude any reactive compensation equipment.

Reflect the User’s opinion of what could reasonably be imposed on the Electricity Transmission System.

The date and time of the forecast maximum Demand (Apparent Power) at the Connection Point

The maximum demand factor which the User would expect its Demand to impose on the Electricity Transmission System.

Details of all loads which may cause significant Demand fluctuations potentially resulting in flicker.

3.14. PREPARATION OF ANNUAL FORECAST DEMAND STATEMENT.

Tajikistan Electricity Transmission System Operator will use the forecast information to prepare an annual forecast demand statement and forecast demand projections for a five-year period. 3.14.1. PROTECTION SYSTEM DATA

The following information is required which relates only to Protection equipment which can trip or inter-trip or block any Connection Point circuit-breaker. This information need only be supplied once and Tajikistan Electricity Transmission System Operator should be notified if any of the information changes

Description, including estimated settings, for all relays and protection systems installed or to be installed on the User's System;

Description of any auto-reclose facilities installed or to be installed on the User's

Type and time delays;

A full description, including estimated settings, for all relays and Protection systems or to be installed on the generator, generator transformer, Station Transformer and their associated connections;

Clearance times for electrical faults within the Generating Unit

Estimated fault clearance time for electrical faults on the User's System directly connected to the Tajikistan Electricity Transmission System

3.15. COMPLEX CONNECTIONS

The extent and complexity of an extension or reinforcement of the transmission system will obviously vary. For a project considered by Tajikistan transmission system to be complex, a more detailed analysis of the project effects may be necessary. Tajikistan transmission system may request users provide additional information to enable detailed analysis. The time required to effect detail technical analysis will clearly depend on the project complexity. Satisfactory results from detailed technical analysis will take precedent over the commercial aspects.





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4. DESIGN AND TECHNICAL REQUIREMENTS

4.1. TECHNICAL REQUIREMENTS

Transmission and Users shall observe Tajikistan electricity industry planning, design, construction, maintenance and operational practice, which is based on historical precedents and updated in the light of ongoing experience. The updating will include the introduction of other well understood international standards, technological improvements in design, materials, equipment and construction.

4.2. GENERAL REQUIREMENTS

Transmission shall ensure the transmission system and all components are designed, constructed, operated and maintained in accordance with:

Prescribed Tajikistan standards and practices.

Where no standards have been prescribed or agreed, relevant international standards shall be considered.

4.3. SYSTEM COMPATIBILITY

Transmission shall ensure the transmission system and any extensions to the transmission system are designed to be compatible with the existing systems and interconnections. This shall include: Electric voltages and frequency

Relevant National Standards and Rules

Transformer vector group connection

Protection coordination with the network to which it is connected

National guidelines

Earthing systems

Fault levels

Power factor

Overhead conductor ground clearances

4.4. DESIGN STANDARDS

Transmission may refuse to connect or energise a User connection if that connection is not correctly

protected or is not within the design rating of the transmission system. Connection may also be refused if

connection could cause adverse effects on normal operation of any part of the power system.

4.4.1. Design Compliance

Transmission may disconnect a User that fails to comply with: The design standards set out in the transmission customer’s, distributor’s or generator’s connection

agreement.

Where a connection agreement does not set out any design standards, agreed standards of high voltage equipment, installation clearances and provision of safe operating and maintenance procedures.

National Requirements in relation to design standards.

4.5. PROTECTION STANDARDS

Transmission shall require, as a condition in a connection agreement, that a potential user requiring

connection, or an existing user connection modification, shall consult with transmission about the design and

selection of equipment for all protection functions that impinge upon the transmission system.

4.5.1. Protection Compliance

Transmission will not connect a potential User unless the protection and control associated with the

connection point complies with: Guidelines issued by transmission

Transmission accept and agree the proposed protection system design.





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Transmission accept the proposed equipment.

Energy measurement equipment is installed and complies with the metering code. 4.5.2. Duplicate Protection

Transmission shall require as a condition in a connection agreement that a user installs duplicate protection

or back up protection that ensures a fault on the user system does not affect the transmission system.

4.5.3. Duplicate Batteries

Users shall ensure DC supplies are uninterruptable for protection systems that affect the transmission

system. This may require installation of duplicate batteries.

4.5.4. System Components

Power system security depends on the design of the protection system as well as coordination of the settings

with Users protection systems. As a minimum the primary protection scheme shall have a backup protection

scheme and shall be provided as appropriate for each User’s system as indicated below: 110 / 220 / 500kV substation bus bars

110 / 220 / 500kV lines

Transformers

Generators

Circuit breakers

Substation auxiliary systems

4.5.5. Types of Protection

The following protective and relay schemes shall be provided as agreed with Transmission for the following

systems:

Category Protection Requirements

110 / 220/ 500kV substations

Busbar differential

Under Frequency Schemes

Lightning protection

Additional busbar protection as required by Transmission

500 / 220 / 110kV Transmission Lines

Distance protection.

Differential (Can be applied to new schemes)

Lightning Protection

Intertripping.

Overcurrent and Earth Fault.

Auto Reclosing

Power Transformers 500 / 220 / 110kV

Differential

Earth Fault

Standby Earth fault

Restricted Earth fault

Overcurrent


Intertripping (Where appropriate)

Buchholz

Temperature

Over voltage

Under voltage.

Over fluxing

Generators

Generator differential

Over current

Over voltage

Under voltage

Loss of excitation

Ground

Over/under frequency





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Category Protection Requirements

Shunt Reactors

The shunt reactors shall be protected from internal as well as external faults. Circuit breakers may be provided for shunt reactors to allow for disconnection of the shunt reactor if an internal fault occurs. If circuit breakers are not provided for each reactor, then protective relaying on shunt reactors shall be used to trip associated line circuit breakers. Isolation shall be provided for shunt reactor and associated circuit breaker maintenance. As a minimum the following relays shall be provided for shunt reactor protection.

Differential

Impedance

Buchholz


Circuit Breakers Breaker fail

Intertripping

Under Frequency and Intertripping Schemes.

To protect from total system collapse Transmission and Users shall cooperate with the installation of under frequency load disconnection schemes and Intertripping schemes.

Instrument Transformers

Current Transformers (CT’s) and Voltage Transformers (VT’s) used in protection systems shall be of the appropriate class, burden and accuracy to ensure correct operation and grading of protection. Protection CT’s and VT’s shall not be shared with commercial metering equipment. Commercial metering CT’s and VT’s shall not be used for protection purposes.

4.5.6. Protection Relay Coordination

Protective relays in the various sub-systems of the power system should be coordinated in such a way that relay protection acts to disconnect only the damaged part of the electrical system, and does not disconnect adjacent to it, undamaged areas or activated under load conditions. Users shall cooperate closely with transmission to ensure the coordination of all protection schemes. Relay coordination shall be reviewed and checked by transmission should a user’s system characteristics change. Users shall notify transmission, in accordance with planning requirements of any change, or potential change, to their system that impinges upon operation of the transmission system. Every five years transmission shall facilitate and check relay coordination with all users. 4.5.7. Relay Testing and Maintenance Periodic testing of protection relays should be effected by transmission and users according to manufacturers’ recommendations and operational experience2 Users protection systems that impinge directly on the transmission system security shall be tested under supervision of transmission. Records shall be kept of all testing and maintenance performed on transmission and users’ protection and control equipment that affects the transmission system. Users test records shall be provided to transmission for review and archiving.

4.6. COMMUNICATIONS

Transmission shall require as a condition in a connection agreement that a User provides voice and data communications for the operation and supervision of the connection point.





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4.7. USER SYSTEM MODIFICATIONS

Transmission shall require as a condition in a connection agreement with a user: A user shall not modify or change any control or protection devices relating to a connection point without the prior agreement of transmission.

When transmission agree to a modification, the user documents the design and equipment changes.

The user shall provide transmission with all documentation relating to the modification or change.

Transmission shall acknowledge receipt of the information provided by the user.

4.8. TRANSMISSION MAINTENANCE AND TEST REQUIREMENTS

4.8.1. Transmission shall maintain and test the system in accordance with: Operational experience.

Routine maintenance schedule.

Condition monitoring.

Manufacturers’ recommendations2 4.8.2. Transmission system maintenance shall be scheduled in accordance with the requirements

of Section 5 (Outages and Maintenance).

4.9. USER MAINTENANCE AND TEST REQUIREMENTS

Users shall maintain and test the part of their system that connects and has an operational effect on the transmission system in accordance with: Transmission requirements.

Operational experience.

Routine maintenance schedule.

Condition monitoring

Manufacturers’ recommendations.

4.10. FAULTS OR INCIPIENT FAULTS

Users shall immediately inform the system operator of actual or incipient faults that are likely to have an effect on the security of the transmission system. The system operator shall confirm receipt of the user information and both parties shall cooperate in eliminating risk to transmission system security.





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5. OUTAGES AND MAINTENANCE

5.1. INTERRUPTIONS OR RESTRICTIONS TO TRANSMISSION SERVICES

The system operator may, subject to anything contrary in connection agreements, interrupt or restrict transmission services for the purposes of: Testing, commissioning, maintenance or repair on a connection point or any part of the transmission network which cannot be undertaken by live-line techniques.

Augmentation or extensions to the transmission system or to connect a new transmission customer, distributor or generator.

Complying with the directions of system control.

Maintaining power system security or responding to an emergency.

As otherwise agreed in writing with the transmission customer, distributor or generator.

5.2. NON-SCHEDULED OUTAGES

Non-scheduled or emergency outages which are required in order to avoid damage to equipment and possible danger to personnel shall receive priority attention.

A non-scheduled outage shall include a scheduled outage which exceeds the specified period of a scheduled outage.

Except in cases of emergency or automatic operation of protection systems transmission shall agree an interruption of service with affected parties. A transmission service interruption shall be mutually agreed by all parties but may not be unreasonably restricted by affected parties.

Transmission must use its best endeavours to minimise the number and duration of any interruption or restriction to transmission services.

Transmission must, on request by a User, provide a verbal and written response within 10 business days explaining, to the extent that the available information at that time allows, any interruption or restriction to the provision of transmission services.

5.3. OUTAGE PLANNING COORDINATION

To ensure the uninterrupted and stable operation of the transmission system collaboration is required between:

Each generator and the system operator in respect of maintenance outages, plant defects and availability.

System operator with generators in respect of transmission outages and system constraints relevant to generators.

System operator with distribution in respect of outages and constraints on the transmission system, connection points or generation.

System operator with each transmission connected customer in respect of outages and constraints on the transmission system, generation and at the transmission connection point relevant to the transmission connected customer.

Distribution with system operator in respect of works or outages that affect transmission or generation.

Transmission connected customer with system operator in respect of works or outages that affect transmission or distribution.

External system operators with the Tajikistan system operator for outages and constraints on either system.

5.4. GENERATION OUTAGE PLANNING

5.4.1. Short Term Generation Outage Planning (Current financial year)

Generators’ short-term outage plans will be for the current financial year and shall be submitted to the system operator at the beginning of the financial year. Generators shall only implement their outage programme after the system operator agrees in writing.

5.4.2. Medium Term Generation Outage Planning (Years 2 and 3 following the current financial year)





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Generators’ medium-term outage plans shall be for the two years following the short-term plan and shall be complied and revised from the previous long-term plans and include deferred work from short term plans. Medium term plans shall be submitted to the system operator at the beginning of each financial year. Changes to the medium-term plans will be discussed and agreed with the system operator during the year. The discussion process will be concluded by the middle of each financial year.

5.4.3. Long Term Generation Outage Planning (Years 4 through 6 following the current financial

year)

Provisional outage plans and functional generation availability shall be prepared by each generator and submitted in writing to the system operator each year for the years four through six from the current financial year.

5.4.4. Forecast Demands and Long-Term Generation Programme

The system operator shall prepare the annual forecast demands including values for peak winter demand. Every effort shall be made by the system operator and generators to agree the final generation outage programme which will satisfy the forecast long term system demand. The long-term generation outage programme and system demand will undoubtedly change with the passage of time according to circumstances and neither transmission or generators are committed to maintain the initially agreed programme.

5.4.5. Transmission Outages and Long-Term Generation Programme

The system operator shall provide all generators with the long-term forecast transmission outages for construction or maintenance. Should there be conflicts between transmission and generation outages, every effort shall be made for resolution, however the transmission outages shall take precedence.

5.5. TRANSMISSION OUTAGE PLANNING

5.5.1. Short term transmission outage planning

The current financial year’s transmission outages will be derived from previous medium- and long-term plans. The short-term plan will also be updated according to exigency.

5.5.2. Outage Changes

All parties utilising the transmission system may at any time during the current financial year request in writing to the system operator, changes to outages previously included in future years’ programmes. The system operator shall determine if the changes are acceptable or otherwise. The requesting party shall be informed in writing of the decision by the system operator, advising them if the proposed changes are acceptable to the system operator. The system operator is not obliged to alter the transmission outage programme because of changes proposed by users.

5.5.3. Outage Cooperation

All parties shall use best endeavours to determine a mutually acceptable solution to proposed changes to outages.

5.5.4. Outage Review

The system operator shall review the final outage programme with all users two months in advance of the proposed outage dates. All parties are obliged to cooperate at this review stage for any requested outage changes. This process of confirming and mutually amending the final outage programme will continue in detail up to the real time operation.

5.5.5. Medium term transmission outage planning (years 2 and 3 following the current financial

year.)

The system operator shall update the transmission outage programme to take account of transmission outages required for system maintenance purposes. All users shall observe the outage requirements.





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5.5.6. Long Term Transmission Outage Planning (Years 4 through 6 following the current financial

year)

Transmission shall provide the system operator with construction and refurbishment long term plans for years 4 through 6 following the current financial year. Maintenance requirements are included in the short- and medium-term plans and are not required to be included in the long-term plans. Users and the system operator shall exchange information during the course of each financial year and by month 10 to arrive at the long-term programmes for years 4 through 6. Following the information exchange period, the system operator shall prepare and disseminate to all users a draft transmission outage programme for years 4 through 6. Users shall be informed of aspects of the long-term outage plans that may cause operational difficulties for any user or necessitate special measures to ensure security of supply.





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6. METERING

6.1. PRINCIPLES

All metering and associated systems between users shall comply with the Tajikistan metering code. Metering facilities shall be provided at all connection points between users and Tajikistan electricity transmission to record energy transfers and other metering data for billing purposes. Some data may also be used for studies and system planning. Until the establishment of an independent metering provider, metering shall be owned by the upstream provider of power. Electricity generators shall own the meters at the interfaces with transmission and in some cases the interfaces with distribution. Transmission shall own the meters at the interfaces with distribution and commercial entities connected to the transmission system. Check meters shall also be provided at interfaces. Metering shall be situated such that the cost of transformation losses shall always be with the Entity that owns the transformer.

Data from metering installations shall be automatically transmitted to the settlements operator. Manual transfer of metering data is not acceptable.

6.2. LOCATION OF METERING POINTS

Meters, including any check meters shall be situated in a control building in a separate and lockable designated metering room. New user installations shall provide a designated metering room that will be accessible by authorised users’ personnel without needing to enter the main control room2 At metered user interfaces without a control building, a weatherproof, heated and lockable building shall be provided for housing the metering and communications equipment.

6.3. APPLICATION

All revenue metering shall provide accurate measurement of electrical quantities delivered through the Tajikistan electricity transmission system. Where power flow is likely to be bidirectional meters shall be of the four quadrant type. Two quadrant metering shall be used at locations where the power flow will be unidirectional. Metering devices including all associated voltage and current transformers shall be of revenue class accuracy in accordance with applicable Tajikistan national standards or IEC standards as indicated in this section. Metered quantities shall be remotely transmitted and recorded in the metering database of the metering system operator. In addition to measuring and recording energy transfers, metering shall incorporate facilities to measure and record:

Apparent power.

Active power.

Reactive power.

Load demand.

Power factor.

Recording and storage of data that will facilitate billing and system planning.

6.4. METERING REQUIREMENTS

Metering shall be situated in a separate cabinet to be located in a secure location such as a control building.

Revenue metering and associated check metering shall use only dedicated voltage and current transformers.

Protection and instrumentation systems shall use separate current and voltage transformers and shall not be shared with revenue metering.

For existing installation where instrument transformers are shared for metering and protection, a metering audit shall be performed to ascertain no unacceptable error due to overload or instrument transformer saturation is introduced in the metering.

Current and voltage transformers shall have a locking termination compartment that can be sealed.

Secondary circuits between CTs and VTs should be installed with insulated copper wires of at least 2.5 mm2.





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Metering cabinets shall be tamper proof and lockable.

6.5. METERING INSTALLATIONS

Future metering installations shall be installed by an independent metering authority at a secured location within the substation where the connection is made between the user and Tajikistan transmission system. Metering and associated equipment shall be installed so as to be tamper proof.

Metering equipment shall be approved by the independent Tajikistan metering authority. Meters and associated equipment shall comply with relevant IEC standards and other applicable national and international standards.

Current and voltage transformers shall be supplied with the manufacturer's test certificates indicating accuracy as well as periodic testing reports.

On site testing of the metering installation shall be conducted by the independent Tajikistan metering authority in the presence of users' representatives.

6.6. TESTING AUTHORITY

The independent Tajikistan metering authority shall be responsible for testing and maintenance of meters and associated equipment. Test and calibration facilities shall be subject to period verification and certification by the relevant Tajikistan authority. Users shall have the right to inspect all facilities and certification documentation. All metering system test equipment shall comply with IEC 60736 or applicable international and national standards to be prescribed by appropriate Tajikistan authority.

6.7. STANDARDS

Three-phase electronic meters shall comply with the following standards: IEC 62052-11 General requirements: metering equipment

IEC 62052-21 General requirements, tests, and test conditions – Part 21: tariff and load

control equipment

IEC 62052-31 General requirements, tests, and test conditions – Part 31: safety

requirements

IEC 62053-21 Particular requirements: static meters for active energy (classes 1 and 2)

IEC 62053-23 Particular requirements – Part 23: static meters for reactive energy

(classes 2 and 3)

IEC 62053-61 Particular requirements – Part 61: power consumption and voltage

Requirements.

IEC 62058-11 Acceptance inspection – Part 11: general acceptance inspection methods

IEC 62058-3 Acceptance inspection – Part 31: particular requirements for static meters

for active energy (classes 0.2s, 0.5s, 1, and 2)

IEC 62056 Electricity metering – Data exchange for meter reading, tariff and load control

Parts 21, 31,41,42, 46, 47, 51, ,52, 53, and 61 depending on the communication method

Metering current and voltage transformers for revenue metering shall comply with applicable International and national standards including:

IEC 60044-1 Part 1: Instrument Current Transformers,

IEC 60044-2 Part 2: Inductive Instrument transformers voltage

IEC 60044-3 Instrument transformer transformers Part 3: Combined

IEC 60186 Voltage transformers





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6.8. METER PERFORMANCE REQUIREMENTS

Revenue metering and ancillary equipment must read active and reactive power delivered to or received from Tajikistan Electricity Transmission System with the appropriate degree of accuracy as specified in applicable IEC Standards, generally not less than +/- 0.2%.

Revenue class metering shall have the following characteristics:

Digital electronic meters, generally with accuracy class of 0.2, shall be in compliance with the Tajikistan Metering Code requirements.

Meters shall be capable of measuring and recording active energy at 30 minute intervals for a period of 70 days with intervals programmable from 5 minutes to 30 minutes.

Meters shall have the capability of recording active power reactive power and maximum demand for the entire billing period. The billing period shall be programmable and capable storing the accumulated values.

Current and Voltage transformer multipliers shall be programmable in the meter.

Meters shall have internal time clock for time and date stamping of data. Clock must have high accuracy and synchronize with GPS time signals.

All meters shall have the capability of remote reading by means appropriate to the location.

Meters shall be self diagnostic and incorporate notification of incipient failure and tampering.

6.9. METERING DATA COLLECTION

Metering data shall be collated and transmitted by means other than manual transfer to the metering system operator. Transmission of metering data shall be secure and tamper proof. The metering system operator shall maintain the metering database in accordance with the metering code for all users of the Tajikistan transmission system. Information from the database shall be accessible for engineering studies and to assist with system planning. The communication protocol for transmitting metering data shall be in accordance with IEC 61107 and amended or updated in accordance with the Tajikistan metering code.

6.10. SETTLEMENT OF ACCOUNTS

Discrepancies in meter readings leading to disputes between users shall be resolved in accordance with the Tajikistan metering code.

6.11. ACCESS

Users shall be entitled to inspect their respective meter installations at all relevant locations. The rights of access shall be in accordance with section 7 of this grid code, access operations and authorisation.

6.12. REVENUE AND TAMPER PROTECTION

Meter installation shall be effected by Tajikistan metering system operator in cooperation with relevant users. After effecting and testing of a metering installation, users shall certify the installation was completed in accordance with the Tajikistan metering code and shall witness sealing of the meter installation.

6.13. METER INSTALLATION TESTING

Meter installations shall be periodically tested in accordance with the Tajikistan meter

TAJ: Regional Power Transmission Project...1.0 01 August 2016 John Cook Peter Graham 2.0 30 March...

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