Alternator Training

93
Training Department ALTERNATOR TRAINING Ersin ERDALI June 06

Transcript of Alternator Training

Page 1: Alternator Training

Training Department

ALTERNATOR TRAININGErsin ERDALI

June� 06

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1. Base Electrical Information2. Alternator Operation Principle3. Alternator Parts and Functions4. Technical Knowledges and Numeral Rules5. Protection Class (IP,H-F)6. 6. TroubleshootingTroubleshooting GuideGuide

INCLUDE OF ALTERNATOR TRAININGINCLUDE OF ALTERNATOR TRAINING

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1. Base Electrical InformationElectromagnetic Field :

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FaradayFaraday��ss LawLaw ::

1. Base Electrical Information

Any change in the magnetic environment of a coil of wire will cause a voltage (emf) to be "induced" in the coil. No matter how the change is produced, the voltage will be generated. The change could be producedby changing the magnetic field strength, moving a magnet toward oraway from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, etc.

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Electrical Definations: Resistance, Unit : Ohm (R)

Resistance is a measure of the degree towhich an object opposes the passage of electric current

Measurement Device : Ohmmeter

Voltage, Unit : Volt (V) Voltage is the difference of electrical

potential between two points of an electricalnetwork

Measurement Device : Voltmeter

Current, Unit : Ampere (A) Moving electrons by voltage and flowing

electrons Measurement Device : Ampermetre 1 Ampere : 6,28x1018 electron /s

IxRV

1. Base Electrical Information

CircuitComponent

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� Alternating Current (AC) :

AC current is changed way andstrenght by the time.

� Direct Current (DC) :

DC current is not changedway and strenght by thetime.

1. Base Electrical Information

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2. Alternator Operation Principle

When the magnetic fieldaround a conductorchanges, a current is induced in the conductor. In a alternator, a rotatingmagnet called the rotorturns within a stationaryset of conductors woundin coils on an iron core, called the stator. Thefield cuts across theconductors, generatingan electrical current, as the mechanical inputcauses the rotor to turn.

Permanent Magnetic Field

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2. Alternator Operation Principle

Sine wave current in eachof the coils produces sine varying magnetic field on the rotation axis. Magneticfields add as vectors.

Vector sum of the magneticfield vectors of the stator coilsproduces a single rotatingvector of resulting rotatingmagnetic field.

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Magnetic field on the windings induce alternating (AC) voltage in main stator.

2. Alternator Operation Principle

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Voltage regulatorsenses induced voltagein main stator to take a referance.

Sensed voltagecompares regulatorsetting values (400 V AC, 50Hz).

Excitation voltagerealize excitation stator via excitation toes of regulator according tothe difference

Referans Giriºleri

Uyartýn Gerilimi DC

Set Deðerleri

2. Alternator Operation Principle

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Diodes rectify DC voltage to inducedAC voltage in excitation rotor toincrease permanentmagnet in mainrotor.

Excitation rotor voltage realizesmain rotor windingswhich rectified DC voltage.

Inputs of DiodesExcitationRotor Voltage AC

Output of Diodes MainRotor Voltage DC

2. Alternator Operation Principle

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3. Alternator Parts and FunctionsAlternators Which We Use :

Stamford / England(12 toes)

Mecc-Alte Spa / ItalyEco series 12 toes (Out of Eco 28)

Leroy-Somer / France

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MainRotor

StatorA.V.R.

RotatingDiodes Plateand Varistor

Alternator

Excitation Rotor

Terminal Box

3. Alternator Parts and Functions

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3. Alternator Parts and FunctionsAlternator Parts (MccAlte Eco 37) :

NAME1 real seal2 casing3 grid5 users terminal board7 rear cover8 frame with stator9 front cover9A front cover MD 3510 exciting stator11 rotating diode bridge12 hub13 exciting armature14 rotor15 fan16 exterior flange bearing cover17 drive-end bearing18 interior flange bearing cover19 rear bearing20 terminal box22 diode holder washer

NAME

23 electronic regulator

24 auxiliary terminal board

28 cover stay bolt

39 protection screen

40 fixing ring

42 parallel device

59 coupling hub

60 disc plates

70 radio disturbs suppressor

94 rear case

95 termin.brd.side panel

96 termin.brd.front panel

97 termin.brd.rear panel

98 regulator carrying panel

99 disc blocking ring spacer

104 component-carryng panel

123 ring spacer

143 exciter stay bolt

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RFI Suppressor

NeutralPoint

Output

Points

U- V- W

Paralleling

Transformer

A.V.R.

Terminal Box (Mecc Alte ECO 34)

3. Alternator Parts and Functions

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A.V.R.

R.F.I. Suppressor

OutputPoints

Terminal Box (Mecc Alte ECO 3)

3. Alternator Parts and Functions

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Terminal Box (Stamford P7 Series) :

Terminal Box

3. Alternator Parts and Functions

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Main Stator :

� Main stator which is made of high qualitysiliceous laminations is mounted by meansof supporting ribs in a sheet steel body.

� Main stator grooves and main rotor polesare designed to minimize distortion on thewaveform. Main stator windings have a shortened pitch to reduce the harmoniceffects on the waveform.

3. Alternator Parts and Functions

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Main Rotor :The rotor is salient-pole type. Damper windings areplaced into the rotor as a standard feature for parallelwork and unbalanced loads. Fan, the main rotor, excitation rotor and the rotating diodes are fitted toshaft . The entire rotor is dynamically balanced.

3. Alternator Parts and Functions

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3. Alternator Parts and Functions

Voltage Regulator (AVR) :

Alternator

VoltageRegulator

LOAD

SettingValues

Reference(Sensing)

This is the most important element of the alternator. At asymmetricalloads, the voltage regulator senses three phases as a reference thereforemaximum voltage asymmetry is 5%. Electrical and thermical tests areapplied before mounting on the alternator. The output voltage could be adjusted manually by a potentiometer.

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Voltage Regulator (AVR) :

Electronic Voltage Regulator(UVR 6 Mecc Alte)

3. Alternator Parts and Functions

To remotely regulate the voltage there areterminals for potentiometer connection.

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Mecc Alte SR 7 UVR 6

Stamford SX 460 SX 440 SX 421 SA 465

S : Self excited

MX 341 MX 321 MA 325M : Permanent Magnet Generator

Voltage Regulators Which We USe :

3. Alternator Parts and Functions

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Mecc Alte UVR6 Voltage Regulator Technical Features:

� 170-270 V AC Supply (with + and 2)� Capability to sense 3 phases or 1 phase� Stable for humidity and vibration� Maximum voltage drop 15%� Capability to set voltage-stability� Protection for low frequence and over current

Delay over current protection Yellow Led

Low frequence protection Red Led

Nominal operation Green Led

3. Alternator Parts and Functions

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Mecc Alte SR7/2 Voltaj Regulator Setting Potentiometer :

VoltageSetting

StabilitySetting

Factory Settings

(Low speed andover load)

3. Alternator Parts and Functions

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Mecc Alte SR7/2 Voltage Regulator Terminal Connections :

Terminal 1 : Excitation windings negative (-) toe.Terminal 2 : It should bridge terminal 3 If SR7/2 regulator supply will be

lower then 160 V AC.Terminal 3 : Excitation windings positive (+) toe and regulator supply.Terminal 4 : Regulator reference voltage.Terminal 5 : Common toe for regulator supply, regulator reference voltage

and external potentiometer connection.Terminal 6 : To bridge terminal 5 for 60 Hz.Terminal 7 : External potentiometer connection.

3. Alternator Parts and Functions

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Stamford SX440 Voltage Regulator Technical Features :

Supply voltage 170-250 Vac Frequence 50-60 Hz nominal Output voltage max. 90 Vdc

(207 Vac input) Output Current 4 A DC

(max. 10 seconds 6 A DC) Regulation ± % 1 Operation Temp. -40°C - +70°C

3. Alternator Parts and Functions

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Stamford MX321 Voltage Regulator Terminal Connections - 1 : Volts:Setting generator output voltage. Stability:Keeping from voltage oscillation, setting steadystate time . Stability Selection:To provide suitable voltage transient. UFRO:Setting underfrequence protection border. Frequency Selection:Providing for suitable operation of UFROprotection. Droop:Enable voltage droop (5 % on full load). Trim:To provide regulator input and accessories uotput. Exc Trip :Over excitation cutting level (5Vdc - %5, 8-15 sdelayed).

3. Alternator Parts and Functions

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DIP:Setting frequence-voltage curve. Over/V:Shuting down excitation voltage WhenÝnput reference voltage to AVR faults(Between terminal E1-E0; 300 Vac, 8-15sdelayed). I-Limit:Maximum short circuit current. Dwell:Voltage tidy up time after on full loaded. RMS:Loading. RAMP:Setting to reach nominal value of outputvoltage by cranking. Factory setting is 3seconds and it�s enough for manyapplications.

3. Alternator Parts and FunctionsStamford MX321 Voltage Regulator Terminal Connections - 2 :

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External Voltage Potentiometer Connection :

� Voltage potentiometercan be connectedterminal 1-2 of all AVR for Stamfor alternator.

� Normally thoseterminals are bridged. Remove those bridgewhen potentiometerconnected.� POT = 4,7 K

Stamford MX321 Voltage Regulator

3. Alternator Parts and Functions

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Rotating Diode Plate :

Rotating Diode Plate Elements :

1. AC Input2. Rectifier Plate3. Diodes � 3 x Negative4. Diodes � 3 x Positive5. Varistor6. DC Output to Main Rotor7. Plate

�Ac voltage is rectified DC voltage to set the permanentmagnet on main rotor via rotating diodes plate which induceexcitation rotor.

� Rotating diode plate is partitioned positive and negative plateand there are 3 diodes both plates (total 6 diodes).

3. Alternator Parts and Functions

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Varistor :Varistors (VDR�s) are a mix of carbon materials that are a highresistance until subjected to a high pressure.

They then becomes a low resistance path to bleed away excessivepressure by allowing lots of amps to momentarily flow throughthe VDR, which has become a momentary low resistance path. This means that the rating of the device based on it only beingasked to conduct for very short period of time and veryintermittently. A VDR that is continually 'clipping� excessivevoltages will get hot and fail.

3. Alternator Parts and Functions

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Excitation Stator and Rotor:

� Excitation stator is provided toinduce magnet for excitation rotor by DC signal via voltage regulator(10-15 V).

�On excitation rotor AC voltage is rectified DC voltage via rotatingdiodes plate and varistor. Thus DC Current is induced for permanentmagnet for main rotor.

3. Alternator Parts and Functions

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Voltage Regulator Supply Devices - 1 :PMG� Provides a separate fixed source impedencepower to AVR & exciter field that is isolated fromthe generator output and is not influenced byexternal load conditions.

� The isolated PMG power supply of the excitationsystem allows the generator to meet low EMI / RFI suppression levels to meet MIL-STD.461C&VDE Class K.

� PMG provides constant power to supply manualvoltage control of the generator & to supplyovervoltage , overcurrent & over excitationprotection circuits.

�Stamford and Leroy-Somer alternators have gotPMG system which we use.

3. Alternator Parts and Functions

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AREPIt is auxiliary windings system to induce AC voltage to supply AVR which is inserted the main stator windings.

Auxiliary windings are thin section. Resistance is lower than mainstator windings.

Mecc Alte alternator has got AREP windings system which we use.

Shunt

AC voltage is provided directly by main stator windings tosupply AVR.

3. Alternator Parts and FunctionsVoltage Regulator Supply Devices - 2 :

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When to Choose PMG or AREP :

Whole installation with several circuits Power cut forbidden High rate of distorting loads. Starting of a big motor Marine, hospitals, stand-by duty, standards in some countries. Arep minimum length required PMG existing shunt machine to be upgraded

When to Choose SHUNT :

Single circuit installation Power cut acceptable Self protection alternator

3. Alternator Parts and FunctionsVoltage Regulator Supply Devices - 3 :

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3. Alternator Parts and Functions

AREP OR PMGTHE ALTERNATOR CONTROLS THE

SITUATIONDURING 10 SECONDS

THE DEFFECT IS RELEASEDTHE BREAKER TRIPS

- THE POWER SUPPLY IS MAINTAINED

OVERLOAD OR SHORT CIRCUITON THE INSTALLATION

SITUATION

SHUNTTHE ALTERNATOR DOES NOT HOLD

THE SITUATIONDESENERGIZING OF THE ALTERNATOR

- THE POWER SUPPLY IS CUTTEN

AREP

SHUNT

PMG

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Brush and Ring Mechanism :

+-+-

+-

3. Alternator Parts and Functions

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Alternator Windings Heater:

HeaterHeater

� Humidity can be reducedisolation resistance on alternator windings. In thatcase heater have to insert thewindings for protection.

�Heaters are 54W-220V forMecc Alte ECO 3-28-31-32-34-38 series. Other heaters are65W-220V for ECO 40-43-46 (Optional 50W-110V).

3. Alternator Parts and Functions

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Bearing :�Bearing is provided to rotate coupled componentsof alternator mandrel (main rotor, excitation rotor, PMG rotor, rotating diodes, etc.) by stability.

�All alternators in Aksa are single bearing.

3. Alternator Parts and Functions

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Fan and Airconditioning :� Alternator windings warme up by and by which induce current inside (J=I2Rt). Warmed windings have to be cooled for efficiency. Fan is used forcooling system.

� Cooling has to be realized for protection of alternator windings. Thereforedon�t close up air intake and drop ball places.

3. Alternator Parts and Functions

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Thermic Protection Components :� Thermic sensors use to protect the warmness of windings in alternator (andin electrical motors).

�PTC thermistor uses in Mecc-Alte ECO 37 � 40 � 43 series alternator bystandard.

PTC Thermistor

Bimetal Contact

PT100 ThermicResistor

3. Alternator Parts and Functions

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RFI Suppressor :

� RFI (Radio Frequency Interference) is noise vibration in alternatorwindings because of magnetic field(>1 kHz).

� Filter with condenser is used toreduce the noises.

� Standards :

BS EN 50081-50082

VDE 0875

BS 1597

MIL 461

3. Alternator Parts and Functions

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Paralleling Transformer:� Paralleling transformer is used forsyncronous operation with other alternatorsand also with the mains.

� This transformer gives for Mecc Alte Eco 40-43 series alternators. It�s optional forother alternators.

3. Alternator Parts and Functions

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Blok Diagram For Alternator With PMG :

3. Alternator Parts and Functions

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Alternator With PMG :MandrelMain RotorMain StatorBearingExcitation RotorExcitation StatorRotating Diodes Plate and VaristorPMG Rotor and StatorTerminal ConnectionsVoltage RegulatorStator CablesReference CablesPMG CablesExcitation CablesMain Rotor Excitation CablesFan and Air-condition

3. Alternator Parts and Functions

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Block Diagram For Alternator With Transformer :

3. Alternator Parts and Functions

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4. Technical Knowledges and Numeral Rules

Mains � Generator Voltages :

� Mains in Turkey ;Phase - Neutral : 220 V AC

Phase - Phase : 380 V AC

Frequence : 50 Hz

� During the generator (or transformer) voltage selection, It has to be rate of 5% voltage difference between operating voltage(380 V AC) and generator nominal voltage(400 V AC). For our generators ;Phase - Neutral : 231 V AC

Phase - Phase : 400 V AC

Frequence : 50 Hz

� For USA;

F: 60 Hz

V : 480/270, 208/120,

240/120

�For India and South Africa ;

F : 50 � 25 Hz

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Generator Operation Powers :

GENERATOR OPERATION POWERS ACCORDING TO ISO 8528-1 STANDARDS:

4. Technical Knowledges and Numeral Rules

Operation On Standby Power Operation On Prime Power Operation On Continuous Power

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Standby Operation(Operation on limited time) :

� This genset operation is used variable loads at no mains.� Load Measure: 110% (1 hour rate of 10% overload per 12 hours).� Annual Operation Time : 500 hours� Application : working centerum, hotels, hospitals, housing estate, resting places, factories and otherrequested stand-by application places.

4. Technical Knowledges and Numeral Rules

Generator Operation Powers :

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Prime Operation(Operation on unlimeted time) :

� On unlimited time, maximum power fromgenerator for variable loads.� Load Measure: 90%� Annual Operation Time: Unlimited� Application: Industrial and commercialcompanies, devoloping companies , cogenerationapplications, rental and marine gensets.

4. Technical Knowledges and Numeral Rules

Generator Operation Powers :

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Continuous Operation :

� On unlimited time, continuous power viagenerator.� Load Measure: 80%� Annual Operation: Unlimited, continuous.� Application: Continuous base load, mains, cogeneration, parallel operation.

4. Technical Knowledges and Numeral Rules

Generator Operation Powers :

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Power Quality and Gauge :�Acceptable values for harmonic distortions accordingto IEC 519-1992 standard;

ForFor VoltageVoltage (V) : (V) : 3% THD3% THD (total (total harmonicharmonic distortiondistortion))

ForFor CurrentCurrent (I) :(I) :5% THD5% THD (total (total harmonicharmonic distortiondistortion))

�More than limited harmonic distortions will be effected big problems and sacrifices.

4. Technical Knowledges and Numeral Rules

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Alternator Lifetime : On normaly condition, alternator lifetime is

approximately about 100.000100.000 hours forcontinuous operation

But ;� Over current� Unbalance loads� Operation on low Cos (power factor) loads� Over ambient temperature� Harmonics (because of warmness)� Less air-condition� Operation on pulverulent places�� HumidHumid placesplaces

will be effected shorter than normaly.

4. Technical Knowledges and Numeral Rules

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Efficiency Of Alternator :EfficiencyEfficiency = = OutputOutput powerpower / / InputInput PowerPower = kWe / kWm= kWe / kWm

Alternator Losts Iron lost (Hysterysis and Eddy current) Copper lost (Because of windings) Friction lost (ballbearing)

Efficiency of alternator depends on current of load. Efficiency of alternator depends on power factor of

load. Efficiency is increased if Cos will increase. Efficiency is reduced if Cos will reduce.

EfficiencyEfficiency of of alternatoralternator is is approximatelyapproximately aboutabout ;; ForFor 500500--1500 kVA 1500 kVA %90%90--9797 ForFor 00--100 kVA %85100 kVA %85--9393

4. Technical Knowledges and Numeral Rules

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Voltage Unbalance Rate:

For example; Output voltages of alternator are about 236, 229, 225 volts;

Voltage unbalance is rated the biggest of 3 phases outputvoltages of alternator (U,V,W) and average output voltage.

4. Technical Knowledges and Numeral Rules

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Effecting Alternator Of Voltage Unbalance :

� Because of voltage unbalance, A small magnetic field is induced on alternator windings which is direct opposite main magnetic field.

� Voltage unbalance effects to warm windings up.

Example Calculation :

Temp. Boost = Nominal Temp x 1 + 2(Voltage Unbalance)2

100

Temp. Boost = 80C x 1+2 = 80C x 1,136(2,61)2

100

Temp. Boost = 90,9 C

4. Technical Knowledges and Numeral Rules

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Setting Voltage Unbalance With �STAB� Potentiometer :

Genset VoltageUnstable

Critical

Good

Slow

No Load Full Load

4. Technical Knowledges and Numeral Rules

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Cos Values Of Electrical Loads :

Electrical Heater 1 Incandescent Lamp 1 3 Phases Motors 0,7-0,9 Fluorescent Lamp 0,3-0,5 Neon Lamp 0,4-0,5 Welder Machine 0,4-0,8

4. Technical Knowledges and Numeral Rules

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4. Technical Knowledges and Numeral Rules

The Power Triangle :There are 3 types of electrical powers :

Apparent Power (S, VA)

True Power (P, W)

Reactive Power (Q, VAR)

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Electrical Power Formulas:

IU3S

P (kW)

Q (kVAr)S (

kVA)

4. Technical Knowledges and Numeral Rules

The inductor does not use any true power. However, to the generator, theinductor �appears� to be consuming power because there is an oppositionto current (inductive reactance) and voltage drop across it.

The generator power is apparently used by the inductor.The total powerused by the inductor and resistor is called appropriately. Apparent Power.

Apparent power is measured in Volt-Amperes (VA) to distinguish it fromtrue power.Apparent power for an inductive circuit can be found bymultiplying the total current by the applied voltage;

Apparent Power (S, kVA)

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True Power (P, kW)

CosSP

P (kW)

Q (kVAr)S (

kVA)

4. Technical Knowledges and Numeral Rules

Electrical Power Formulas:

Inductance and resistance characteristics are both present in industrial motors which consist of many coils of wire.

The coils cause current to lag voltage as in an inductor and becauseof coil length, the motor also has resistance.

AC generator is used to provide power to a motor. The resistor is the only component that comsumes power.

The power used by a resistor is called True Power.

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Reactive Power (Q, kVAR)

SinSQ

P (kW)

Q (kVAr)S (

kVA)

4. Technical Knowledges and Numeral Rules

Electrical Power Formulas:

We know that reactive loads such as inductors and capacitorsdissipate zero power, yet the fact that they drop voltage anddraw current gives the deceptive impression that they actuallydo dissipate power. This �phantom power� is called reactivepower, and it is measured in a unit called Volt-Amps-Reactive(VAR).

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P (kW)

Q (kVAr) S (kVA)

CosSPIUS

S

3

kVA100

We will calculate full load current for 100 kVAgen-set at Cos=0,8 and Cos=1 ;

4. Technical Knowledges and Numeral RulesExample Calculation For Electrical Powers - 1 :

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Firstly we should calculate active power outputof gen-set (Cos=0,8 for gen-set and it�sconstant).

FollowingFollowing thatthat ;;

4. Technical Knowledges and Numeral RulesExample Calculation For Electrical Powers - 2 :

kW808,0100 PPCosSP

Amper 5,1448,04003

80000

3

3

için; 8,0

IICosU

PI

CosIUP

Cos

Ampere

For Cos=0,8

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4. Technical Knowledges and Numeral Rules

Amper 6,11514003

80000

3

3

için; 1

idi..kW 80

IICosU

PI

CosIUP

CosP

For Cos =1

Ampere

Example Calculation For Electrical Powers - 3 :

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Calculation For Pole Number :

Hz : Hz : FrequenceFrequence N : Engine speed (rpm) K : Pole number120

KNHz

NHzKKNHz

120

120

ExampleExample ::

WeWe willwill calculatecalculate alternatoralternator polepole numbernumber at 1500 at 1500 rpmrpm of of engine engine speedspeed..

4. Technical Knowledges and Numeral Rules

Kutuplu 41500

50120

KK poles

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4. Technical Knowledges and Numeral Rules

Suitable Generator Selection - 1 : A gen-set for 1000 kVA will supply a load for 900 kVA andCos = 0,5 . We wiil calculate that; is it suitable power of generator or not? (For all gen-set; Cos = 0,8 constant).

At the first we should calculate true power and reactivepower both gen-set and load. Following that;

For Gen-Set : Sgen = 1000 kVA Cos ö = 0,8

For Load : Sload = 900 kVA Cos ö = 0,5

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4. Technical Knowledges and Numeral Rules

Suitable Generator Selection - 2 :

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4. Technical Knowledges and Numeral Rules

Suitable Generator Selection - 3 :

Suitable Generator Selection :

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Relation Between Voltage and Speed :

� Alternator output voltage is rate of 75% at engine speed rate of 75%.

� Alternator output voltage is rate of 10% at engine lowspeed

� This graph is from Mecc-Alte alternator.

4. Technical Knowledges and Numeral Rules

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No voltage reduction if no over load current (speed is fixed).

Voltage is reducing on short circuit. Therefore short circuit opensettings of thermic-magnetic circuit breaker should be according to3ln.

4. Technical Knowledges and Numeral Rules

Relation Between Voltage and Current :

� This graph is from Mecc-Alte alternator.

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Windings Connections For 12 Lead Alternators :

Series Star For 3 Phases

Sysytems, 400 Vac (L-L), WithWith neutralneutral, ,

230 Vac (L-N)

Series Delta For 3 Phases

Sysytems, 230 Vac (L-L), No No neutralneutral

Parallel Star For 3 Phases

Sysytems, 200 Vac (L-L), WithWith neutralneutral, ,

115 Vac (L-N)

We use difference connections on alternator to provide difference voltages by easily. Accordingly possibility 115/200/230/400 Volts 50Hz on 12 lead alternators.

4. Technical Knowledges and Numeral Rules

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Parallel Delta For 3 Phases

Sysytems, 115 Vac (L-L), No No neutralneutral,,

3 Phases Zig-Zag For 3 Phases Sysytems, 346 Vac (L-L), WithWith neutralneutral.. Alternator output power

multiple 0,8660,866 (346/400)

346 Vac 346 Vac (L(L--L)L)

115 Vac 115 Vac (L(L--L)L)

4. Technical Knowledges and Numeral RulesWindings Connections For 12 Lead Alternators :

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Single Phase Parallel Zig-Zag For Single Phase Sysytems, 230 Vac (L-L), WithWith neutralneutral,, Usually this connection uses

in Europe�s countries.

230 Vac 230 Vac (L(L--L)L)

Double Delta For Single Phase Sysytems, 230 Vac (L-L), WithWith neutralneutral,, Usually This connection uses

in Asia�s and America�scountries. This is the sameconnection type of singlephase parallel zig-zag.

230 Vac 230 Vac (L(L--L)L)

4. Technical Knowledges and Numeral RulesWindings Connections For 12 Lead Alternators :

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Alternator Electrical Drawing :

AVRU

V

W

170-250 V AC (PMG, AREP, Shunt)

Voltage Regulator Supply

VDC

+

-

Excitation

Stator

Uncontrolled 3 Phases

Bridge Rectifier

VDC

+

-

VARÝSTOR

Main

Rotor

Main

Stator U

V

WReference

Points

PMG Stamford, Leroy-Somer

AREP Mecc Alte

4. Technical Knowledges and Numeral Rules

Excitation

Rotor

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5. Protection Class (IP,H-F)IP (Ingress Protection) Code:

The International Protection code, sometimes called the Ingress Protection code, classifies the protection given by an enclosure against the touching of live parts, contact with moving parts and protection against the ingress of solid bodies.

It additionally specifies protection against the harmful ingress of liquids. Two (sometimes 3) digits are used to describe its protection rating, called the IP code.

IP 2 3 C H IP : Ingress Protection 2 : 1. Number (0-6 or X) 3 : 2. Number (0-8 or X) C : Addition letter depends on request ( A,B,C,D) H : Finishing letter depends on request (H,M,S,W)

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1.NumberProtection from solid object

0 : Non protected 1 : Protected against solid object greater than 50 mm 2 : Protected against solid object greater than 12 mm 3 : Protected against solid object greater than 2,5 mm 4 : Protected against solid object greater than 1,0 mm 5 : Dust protected 6 : Dust tight

5. Protection Class (IP,H-F)Protection Class According to DIN 40050 Norm:

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Protection Class According to DIN 40050 Norm:

2.NumberProtection from moisture

0 : Non protected 1 : Protected against dripping water 2 : Protected against dripping water when tilted up to 15° 3 : Protected against spraying water 4 : Protected against splashing water 5 : Protected against water jets 6 : Protected against heavy seas 7 : Protected against effect of immersion 8 : Protected against submersion

5. Protection Class (IP,H-F)

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3.LetterAddition letter depends on request ( A,B,C,D)

For Dangerous Places ; A : With hand B : With finger C : With equipment D: With wire

protection to arrive

5. Protection Class (IP,H-F)Protection Class According to DIN 40050 Norm:

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4.LetterFinishing letter depends on request(H,M,S,W)

For Dangerous Places ; H: High voltage device M: Testing against water input demaged when the

moving parts act (exp: rotor) S : Testing against water input demaged when the

moving parts stop (exp: rotor) W: Suitable to use on specified weather condition

and addition protection features

5. Protection Class (IP,H-F)Protection Class According to DIN 40050 Norm:

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ISOLATION CLASS OF INSULATOR MATERIALS ACCORDING TO VDE 0530 STANDARD:

� CLASS H ISOLATION :

Allowable maximumtemperature is about180°C�dir. (Operationtemperature is about130°C)

� CLASS F ISOLATION :

Allowable maximumtemperature is about155°C�dir.

5. Protection Class (IP,H-F)

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6. 6. TroubleshootingTroubleshooting GuideGuide

Before The Maintenance :

Before any cleaning, lubrication ormaintenance operation, ensure thatthe genarator is stationary anddisconnected from the powersupply

The people in charge of thehandling must always wear workgloves and safety shoes

Do not operate the generator withprotective covers, access covers orterminal box covers removed.

Disable engine starting circuitsbefore carrying out maintenance

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Alternator Maintenance :

Lubricating :� Lubricating components should be cleanly.� Using the suitable oil.� Operate the alternator and shooting outthe excess oil.

Ballbearing Lifetime :� For the maintenance-free ball bearingsapproximately 30.000 hours

� For the lubricatable ballbearings approximately40.000 hours

6. 6. TroubleshootingTroubleshooting GuideGuide

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Checking The Windings :

Resistance Test� According the alternator manual values; measuring and comparing windings resistanceof the main stator-rotor and excitation stator-rotor.

Insulator Test�Measure main stator-rotor and excitationstator-rotor with the meger (1MOhm).

� Before test remove all connections of theAVR.

� During the test 500 V AC effect the windings.

6. 6. TroubleshootingTroubleshooting GuideGuide

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� Study the problem thoroughly before acting.� Refer to the alternator system diagrams.� Check the control unit and all cable connections� Do the easiest and most logical things first.� Find and correct the cause of the problem.

6. 6. TroubleshootingTroubleshooting GuideGuideFollow the suggestions below for troubleshooting :

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Troubleshooting - 1 :

� Alternator does not excite ?

Type of Troubleshooting Solving the trouble

Faulty fuse

Low permanent voltage

No permanent voltage

Substitute fuse

Increase speed 15%.

Shock the main rotor bypolarity.

6. 6. TroubleshootingTroubleshooting GuideGuide

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� Low voltage at no load ?

Voltage potentiometer is out of balance

Regulator is protected

Faulty windings

Faulty regulator

Set the voltage potentiometer

Check engine speed

Check the windings

Substitute the regulator

6. 6. TroubleshootingTroubleshooting GuideGuide

Troubleshooting - 2 :

Type of Troubleshooting Solving the trouble

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� High voltage at no load ?

Voltage potentiometer is out of balance

Faulty regulator

Set the voltage potentiometer

Substitute the regulator

6. 6. TroubleshootingTroubleshooting GuideGuide

Troubleshooting - 3 :

Type of Troubleshooting Solving the trouble

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� Normal voltage at no load, than lower voltage at loaded

Regulator is protected

Faulty regulator

Faulty diodes

Current too high, power factorlower than 0.8, speed lower than4% of rated speed.

Substitute regulator

Check diodes

6. 6. TroubleshootingTroubleshooting GuideGuide

Troubleshooting - 4 :

Type of Troubleshooting Solving the trouble

Page 90: Alternator Training

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Faulty Regulator Substitute regulator

6. 6. TroubleshootingTroubleshooting GuideGuide

Troubleshooting - 5 :

Type of Troubleshooting Solving the trouble

� Normal voltage at no load, than higher voltage at loaded

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� Unstable voltage ?

Unbalance engine speed

Faulty regulator

Stability potantiometer is out of unbalance

Set the engine speed

Substitute regulator

Regulate stability of regulator byacting on �STAB.� potentiometer.

6. 6. TroubleshootingTroubleshooting GuideGuide

Troubleshooting - 6 :

Type of Troubleshooting Solving the trouble

Page 92: Alternator Training

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� Abnormal Noises ?

Faulty ballbearings Substitute ballbearings

Check the assembly bolts. Ifit needs, substitute bolts

6. 6. TroubleshootingTroubleshooting GuideGuide

Troubleshooting - 7 :

Type of Troubleshooting Solving the trouble

Unstuck assembly

Page 93: Alternator Training

Ersin ERDALI 93

ALTERNATOR TRAINING FINISHED

QUESTIONS

ANSWERS

THANKS