Christian PAYERL ABB FACTS Grid connection of Wind Farms · Point A is equivalent to: 0.95 leading...
Transcript of Christian PAYERL ABB FACTS Grid connection of Wind Farms · Point A is equivalent to: 0.95 leading...
© ABB Group May 28, 2010 | Slide 1
ABB FACTS Grid connection of Wind Farms
Christian PAYERL
© ABB Group May 28, 2010 | Slide 2
ABB – Power of Wind
© ABB Group May 28, 2010 | Slide 3
ABB FACTS
300 engineers, highly skilled in the following disciplines:
Development
Marketing and Sales
System studies and design
Project management
Quality control
Testing and commissioning
After sales
© ABB Group May 28, 2010 | Slide 4
FACTS Applications Flexible AC Transmission Systems
© ABB Group May 28, 2010 | Slide 5
FACTS Business structure and development
Static Var Compensation - Utilities Series Compensation
TCSC
© ABB Group May 28, 2010 | Slide 6
SVC Light® (STATCOM) SVC for Power Quality
FACTS Business structure and development
© ABB Group May 28, 2010 | Slide 8
ABB SVC Installations
450 SVC installations (more than 310 for Power Quality)
© ABB Group May 28, 2010 | Slide 9
SVC - Static Var Compensator SC – Serial Compensations
Start of research
First commercial installation
Installed power
Number of installations
1967 1945
1972 1950
52.000 Mvar 60.000 Mvar
415 235
© ABB Group May 28, 2010 | Slide 10
Generator Size Background
© ABB Group May 28, 2010 | Slide 11
System Studies - Grid Codes Many markets are currently installing or discussing
installing large amounts of renewable generation
Of all the renewable energy sources, wind is currently the most viable technology
In the past wind farms were generally small (ten’s of MWs) and connected mainly to distribution systems
Today most of the wind farms planned are +100 MWs and many are being connected to sub-transmission and transmission level
This prompts the need for systems analysis in the early stages of wind farm development to ensure proper integration into the transmission system
Background
Why shall large wind plants NOT match the same demands as other large traditional power plants ?
© ABB Group May 28, 2010 | Slide 12
Grid Connection
Onshore
Offshore
AC networkCollection
grid
On-shore S/S
Reactive PowerCompensation
Off-shore HVSubstation
Sub-Sea Export Cable transmission
Background
© ABB Group May 28, 2010 | Slide 13
Reactive Power Balance
Voltage Stability
Frequency Control
Fault Ride-Through
Power flow
Critical aspect, Grid compliance - wind power
PICTUREJPG-FORMAT
WEB OPTIMIZED RESOLUTION
General
© ABB Group May 28, 2010 | Slide 14
Voltage & Transient Stability
Power Oscillation Damping
Load Balancing
Power quality issues
Harmonic Mitigation
“Flicker” Mitigation
Voltage Transient Issues
Resonance Issues
Other Advantages with an SVC at the GCP
PICTUREJPG-FORMAT
WEB OPTIMIZED RESOLUTION
General
© ABB Group May 28, 2010 | Slide 15
Static analysis To define apparatus data and reactive
power demand
Load flow
Short circuit
Dynamic analysis To verify system design
Harmonics
Transient Stability
Transient overvoltage
Relay coordination
Power quality analysis Harmonics
Flicker
System Design Studies
© ABB Group May 28, 2010 | Slide 16
European Wind Integration Study - EWIS
EWIS – Report
Page 22, page 24, page 47f
General
© ABB Group May 28, 2010 | Slide 17
Large Wind Farm Grid Connection
Source: National Grid
Reactive PowerBalance
© ABB Group May 28, 2010 | Slide 18
Reactive PowerReactive Power is a local phenomenon and cannot be transmitted
effectively across large distances.
Reactive PowerBalance
The German power factor requirements for Prated above 100MW
© ABB Group May 28, 2010 | Slide 19
Reaktive power balance
Grid Connection Point
Important impedance
P=Pgen-losses
Q=Qgen+Qcabel-I2XPgen
SVC
IG
DFIG
FPC
Qgen
Lagg
ing
MVa
rLe
adin
g MW
MVa
r Lagg
ing
Lead
ing MW
Lagg
ing
MVa
rLe
adin
g MW
+.95pf
-.95pf
Reactive PowerBalance
© ABB Group May 28, 2010 | Slide 20
Reactive power balance
Generators giving local reactive power support are being retired, this disturbs reactive power balance.
Load sensitivity regarding both fundamental frequency and harmonic voltages is increased. Customers are more sensitive to outages.
Changed and often reversed power flow calls for studies and actions.
Reactive PowerBalance
© ABB Group May 28, 2010 | Slide 21
Typical Requirement at the Connection Point (NGT)
Reactive PowerBalance
P (MW) Rated Power output (MW) 100%
20%
A C D B Q (MVAr)
Point A is equivalent to: 0.95 leading Power Factor at Rated MW outputPoint B is equivalent to: 0.95 lagging Power Factor at Rated MW outputPoint C is equivalent to: -5% of Rated MW output Point D is equivalent to: +5% of Rated MW output
© ABB Group May 28, 2010 | Slide 22
Possible FACTS Application
An SVC at the Connection Point can be used to control the entire, or part of, the reactive power.
An SVC at the Connection Point makes it possible to minimize the losses within the wind farm and mitigates the risk for over voltages as well as reduce resonance problems.
Reactive PowerBalance
© ABB Group May 28, 2010 | Slide 23
Historically, wind farms have been excluded from the demand that generating devices should contribute to voltage stability. They cannot, however, expect to enjoy this favorable treatment forever.
Many regulatory authorities adapt the requirement that the wind parks should be able to vary there reactive power output depending on the grid voltage level.
Voltage Stability, Introduction
PICTUREJPG-FORMAT
WEB OPTIMIZED RESOLUTION
Voltage Stability
© ABB Group May 28, 2010 | Slide 24
Possible FACTS Applications
An centrally placed SVC stabilizes the grid.
A solution with an SVC at PCC contribute to voltage stability independent of the active power production.
Voltage Stability
© ABB Group May 28, 2010 | Slide 25
PICTUREJPG-FORMAT
WEB OPTIMIZED RESOLUTION
Frequency control
As well as for the voltage stability,
new wind generation units are requested
to contribute to frequency stability.
Frequency Control
© ABB Group May 28, 2010 | Slide 26
Frequency controlFrequency
Control
© ABB Group May 28, 2010 | Slide 27
Possible FACTS Applications Frequency Control
Active power needed.
A FACTS device equipped with an energy storage is a possible solution.
Clustering of smaller wind farms into larger production units makes it easier to apply solutions.
© ABB Group May 28, 2010 | Slide 28
Fault ride through
Minimum fault the system is required to survive.
Symmetric and asymmetric faults.
Depending on voltage level at Connection Point.
Post fault behavior.
Minimum active power as compared to before event.
Reactive power and voltage control.
FaultRide-Through
© ABB Group May 28, 2010 | Slide 29
Fault ride throughFault
Ride-Through
© ABB Group May 28, 2010 | Slide 30
Advantages with an SVC at Connection Point
Fault Ride-Through is first and foremost a question for the Wind turbine generator manufacturers.
An SVC can have a significant impact on the system after clearance of the fault.
FaultRide-Through
© ABB Group May 28, 2010 | Slide 32
Wind Turbine Concepts
Fixed speed
Induction generator (SCIG - fixed speed)
Danish concept (2
Induction generator with variable slip (WRIG)
Variable speed
ASG with Inverter system (SCIG)
Double feed induction generator with PWM inverter (WRIG)
SG with Inverter system
General
© ABB Group May 28, 2010 | Slide 33
Reactive power, voltage control
Voltage stability, fault ride through
Induction generator direct connected to the grid
© ABB Group May 28, 2010 | Slide 35
Reactive power, voltage control
Voltage stability, fault ride through
Danish concept
© ABB Group May 28, 2010 | Slide 36
Reactive power, voltage control
Voltage stability, fault ride through
Induction generator with variable slip
© ABB Group May 28, 2010 | Slide 37
Reactive power, voltage control
Voltage stability, fault ride through
Wind turbine with inverter in main power circuit
© ABB Group May 28, 2010 | Slide 38
Synchronous generator
Pitch control wind turbine Variable Speed Multi-Pole Synchronous
Generator – direct driven Rectifier + Inverter
wind
SG
ACAC
Gtransformer
grid/standalone
PowerConverter
© ABB Group May 28, 2010 | Slide 39
Reactive power, voltage control
Voltage stability, fault ride through
Double feed induction generator with PWM-inverter
© ABB Group May 28, 2010 | Slide 42
Background
Modelling aspects
Aspect Model level Time scale Tool
Wind turbines mechanical loads RMS 10-1 s – 103 s HAWC
Wind turbines power quality RMS 10-1 s – 103 s DigSilent
Wind turbine control system RMS/EMT 10-3 s – 102 s Matlab
Wind turbine switchings EMT 10-3 s – 101 s DigSilent/SABER
Grid faults EMT 10-6 s – 10-1 s PSCAD, EMTDC, SIMPOW, DigSilent
Power electronic control and design EMT 10-9 s – 10-2 s SABER
Other aspects
© ABB Group May 28, 2010 | Slide 43
Harmonic Requirements Harmonic emission
Background emission onshore grid
WTG:s System resonance
200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400FREQUENCY HZ
0
200
400
600
800
1000
0
200
400
600
800
0,0
10,0
20,0
30,0
40,0
50,0
0,00
1,00
2,00
3,00
4,00
5,00
6,00
NODE PL33-W5B U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W6A U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W4A U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W3A U POS. p.u. 33.0000/ SQRT[3] kV
Harmonic Filter Design
Type of filter, S-filter, C-filter, etc.
Resistor for increased damping
Resistor => Heating => Losses => Forced Ventilation
Network studyNetwork study
© ABB Group May 28, 2010 | Slide 44
Reasons for bad power qualityPower Line (T or D)
200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400FREQUENCY HZ
0
200
400
600
800
1000
0
200
400
600
800
0,0
10,0
20,0
30,0
40,0
50,0
0,00
1,00
2,00
3,00
4,00
5,00
6,00
NODE PL33-W5B U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W6A U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W4A U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W3A U POS. p.u. 33.0000/ SQRT[3] kV
↨ P, ↨ Q
IG
DFIG
FPC
Power quality
© ABB Group May 28, 2010 | Slide 45
What is flicker ?IEC 61000-3-7,
IEC 61400-21
UK, P28
China, GB/T 12326-2000
Flicker
Definition
A group exposed to a flicker dose of Pst(99%) = 1.0, 50 % of them can observe the light flicker.
© ABB Group May 28, 2010 | Slide 46
Network In/out switching
Tower shadow
Power electronic failure
Background flicker
Flicker
© ABB Group May 28, 2010 | Slide 47
Continouse operation
Switching operation
Flicker
© ABB Group May 28, 2010 | Slide 48
Can harmonics create problems ?
IEC 61000-3-6, THD < 3.0%, Odd.. Even ..
IEC 61400-21
China, GB/T 14549-93
IEEE, THD < 1.5 %, Odd, even, current..
Communication systems and modern remote metering devices (Turtle)
Overheating of power transformers
Harmonics
© ABB Group May 28, 2010 | Slide 49
Network
200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400FREQUENCY HZ
0
200
400
600
800
1000
0
200
400
600
800
0,0
10,0
20,0
30,0
40,0
50,0
0,00
1,00
2,00
3,00
4,00
5,00
6,00
NODE PL33-W5B U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W6A U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W4A U POS. p.u. 33.0000/ SQRT[3] kV NODE PL33-W3A U POS. p.u. 33.0000/ SQRT[3] kV
DFIG
FPC
Harmonics
© ABB Group May 28, 2010 | Slide 50
Shunt banks Small SVC Full rated SVC SVC Light (STATCOM) SVC Light Energy Storage Hybrid solutions
ABB Smart Grid Wind power integration in networks
ABB Solutions
© ABB Group May 28, 2010 | Slide 52
Mechanical switched capacitors from ABB
SIKAP - enclosed capacitor bank
Q-bank - open capacitor bank
CHARM – filter banks
ABBACUS – containerized capacitor bank 12-24 kV
EMPAC- enclosed capacitor bank 36 kV
ABB Solutions
© ABB Group May 28, 2010 | Slide 53
SVC Light with energi storage - applications
February 12, 2010| Slide 53© ABB Group
ABB Solutions
© ABB Group May 28, 2010 | Slide 54
SVC Light Energy Storage
Energy storage connected on DC-side of converter (SVC Light)
Size depends on power level and duration
Charge energy equal to load energy
Focus on “dynamic”, manages:
High number charge and discharge cycles
High Power at medium duration
Chosen high performance battery as energy storage
ABB Solutions
© ABB Group May 28, 2010 | Slide 55
SVC Light Energy Storage SVC Light
First project in 1999 for flicker mitigation of electric arc furnace
In total 12 project for both industry and utility applications
Power range up 164 Mvar, direct connected without transformer up to 35kV grid
SVC Light Energy Storage First project in 2009 Energy Company in UK System Voltage 11 kV Reactive Power:
600 kVAr inductive 600 kVAr capacitive
Active Power: 200 kW during 1 hour 600 kW (short time) Picture of the new Li-ion battery
after testing, October 2008
ABB Solutions
© ABB Group May 28, 2010 | Slide 56
SVC Light med energilager
© ABB Group
Cell Module Room
String Storage
February 12, 2010| Slide 56
ABB Solutions
© ABB Group May 28, 2010 | Slide 57
SVC Light med energilager
February 12, 2010| Slide 57© ABB Group
50 m65 m
Typisk layout för 20 MW under 15 mininuter och +/-30 Mvar kontinuerlig
ABB Solutions
© ABB Group May 28, 2010 | Slide 62
AC Offshore system issues
PCC
PQ working area
Compensation(Localization?!)-Static-Dynamic-SVC vz STATCOM-SVC Light/DynaPow-MINICOMP
Cable parametersCable cost-Laying/burying-Trench width
Harmonics
Energization
Shield overvoltage
XkWeight
ProtectivecapacitorGrounding
-System-Equivpotential
Voltage level
Vt and ferroresonanceABB do not have a voltage divider above 24 kV
Aux. Power-Diesel-Energy Storage
RMU 36 kV
Protectivecapacitor
Type, ratio
Redundancy
RC-protectionSurgearresters
Faultcurrent
CircuitBreaker-Vaccum
Power Electronics
Booster
BLASIGGearbox
d d
Bergeron study, n*d
Fault detection-Ground faults-Short Circuit Currents-Need for further protection?
EMTDC model from SANDYS
Grounding?
CableShielding
Separate 600 V auxiliary grid?
Platform
Ride through
Thermal Cyclic rating
Lightning
Collection Grid Switchboard-Energizing-Normal Operation
ABB Off-shoreSolutions
© ABB Group May 28, 2010 | Slide 67