ACCIONA WINDPOWER WIND POWER PLANTS AND GRID INTEGRATION EXPERIENCE

2010 –Friday 23th April

Óscar Alonso Teresa ArlabánAlberto GarcíaAlejandro González

Authors statement

As a consequence of the Island volcano ash any author of the present paper has been attending the 2010 EWEC conference in Warsaw. Our commitment with the attendees and conference organizers has lead us to prepare a new presentation with audio tracks where you will hear the voices of Oscar Alonso and Teresa Arlaban introducing and highlighting the most important aspects of our work.

We apologize for any inconvenience and hope you find our work interesting and useful. At the end of the presentation you will see our contact email. Feel free to contact us for any question or doubt.

Our Best Regards.

Óscar Teresa Alberto Alejandro

Introduction- TSO – DSO Grid Requirements:

- Voltage support: Normal and Transients.- International approach.- Compliance of: turbines and subs controls

- AW turbine capabilities (AW1500/3000)

- Reactive power & LV/HV RT capabilities

- Substation level voltage control.

- Last experience: Waubra - Australia.

- Future trends: Preliminary research results.

1GRID SUPPORT REQUIREMENTS

- Every country establishes distinct specs.

- Different requirements for transmission or distribution lines.

- Current demands mainly focused on following aspects:

- Normal operation – small voltage variations.

- Transients: LVRT and HVRT.

- Quality: Flicker, harmonics, unbalance, etc

- Protections.

- Metering .

1 .- Scope of the current operator demands

1GRID SUPPORT REQUIREMENTS

- Normal demands:

- 5% voltage steps response in 1 to 5 s.

- Reactive power range: +/- 35% Rated Power.

- Operation on voltage range (PCC): +/- 15%.

- Set point accuracy higher than 0.5 %.

2 .- Voltage Controls

3.- LVRT – International Comparison – Balance/unbalance

AWP technology

1GRID SUPPORT REQUIREMENTS

4.- Implications

1GRID SUPPORT REQUIREMENTS

- Turbine level:

- Increased reactive power range (40%).

- Efficient reactive power management.

- Improved LVRT/HVRT techniques.

- Substation Level:

- Improved technology (control & comms).

2- Variable Speed – Low loads

- Rated Power: 1500 / 3000 kW

- IGBT-Based Power converter.

- Doubly Fed Induction generator:

- 6 pole – 1000 rpm.

- 50 / 60 Hz

- Pitch Control – Hydraulic

- Three-bladed. Horizontal Shaft.

- High Efficiency: 12 kV supply.

ACCIONA WINDPOWER TURBINES: AW1500 / 3000

1 .- General Characteristics

2ACCIONA WINDPOWER TURBINES: AW1500 / 3000

Design - Robust – Reliable - Efficient

AW1500

AW3000

2ACCIONA WINDPOWER TURBINES: AW1500 / 3000

2.- Extended Reactive Power Range: 40%

Curva Nominal Potencia Activa - Potencia Reactiva/Rated Active - Reactive Power curve

0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

-700 -600 -500 -400 -300 -200 -100 0 100 200 300 400 500 600 700

Q [kVAr]

P [k

W]

Curva Nominal Potencia Activa - Potencia Reactiva/Rated Active - Reactive Power curve

0

500

1000

1500

2000

2500

3000

-14

00

-12

00

-10

00

-80

0

-60

0

-40

0

-20

0 0

20

0

40

0

60

0

80

0

10

00

12

00

14

00

Q [kVAr]

P [

kW

]

AW1500 AW3000

Increased Reactive Power capability implies:

Increased power converter & generator ratings

3 .- LVRT / HVRT New Torque and Pitch strategy

- Based on “available active power” (depends on the remaining voltage and reactive current injection)

- Available torque is used to damp oscillations.

- Fast Pitching to get pre-calculated steady angle.

2ACCIONA WINDPOWER TURBINES: AW1500 / 3000

Max = 1272.12 rpmMax = 1246.5 rpm

88 rpm 38 rpm

2ACCIONA WINDPOWER TURBINES: AW1500 / 3000

Example (LVRT test)- 90% Volt depth and 2s long.-Turbine load 90%.

2ACCIONA WINDPOWER TURBINES: AW1500 / 3000

3 .- LVRT / HVRT New Torque and Pitch strategy

Old Techniques New Techniques

Consequences- Longer and deeper

voltage dips.- Reduction of

oscillations and mechanical loads.

3VOLTAGE CONTROL – WAUBRA (AUS)

1 .- WAUBRA (AUS) Characteristics & Requirements

- 128 wind turbines model AW1500.

- POI at 220 kV – 2 transformers 220 kV / 66 kV / 150 MW

- Five substations 66 kV / 12 kV.

- Two voltage controllers:

- Transformer 1. 66 kV side.

- Transformer 2. 66 kV side.

- Requirements:

- Response for voltage steps of 5% in less than 5 secs.

- Reactive capacity +/- 30% Rated Power.

2 .- Voltage Control Principles

Comms: 200 ms polling cycle

Parameters:KpTiFilter

3VOLTAGE CONTROL – WAUBRA (AUS)

3 .- Set point step tests

Set Point steps

Pink – Substation Reactive powerBlue – Substation Voltage

Saturation

3VOLTAGE CONTROL – WAUBRA (AUS)

4.- Transformer Tap changer tests

Transformer Tap changer test

Pink – Substation Reactive powerBlue – Substation Voltage

2 - 3 s max response time

3VOLTAGE CONTROL – WAUBRA (AUS)

5 .- Coordination after LV or HV faults (Now, standard)

Smoothed reactive power restorationRamp up/down 30 to 50 kVAr/s

LV event – 0.5 s (real measurement)

Sub Control Sub ControlTurb Control

3VOLTAGE CONTROL – WAUBRA (AUS)

1 .- Improved Voltage control

- Same control for weak (SCR<2) or strong grids (SCR>10).

- Detection of the grid characteristics:

- Fast grid impedance selection method.

- Fast estimation algorithm of the Thevenin grid voltage.

- Principle of operation: Steady-state pre-calculated response.

- Accurate, robust and safe even with long polling times.

- Patents pending.

4FUTURE DEVELOPMENTS

4FUTURE DEVELOPMENTS

1 .- Improved Voltage control (1 – 2 s response)

Set Point changes

RX grid change (SCR 20 to less than 4!)

Grid voltage changes

4FUTURE DEVELOPMENTS

2 .- Accredited Grid Integration field test report

Field tests to demonstrate grid code compliance.

Certified Laboratory testing and accredited procedure

(international acceptability).

- Turbine level:

- LVRT and HVRT according to most exigent grid codes.

- Active power management: Primary, inertial response, power reserve.

- Protections. Harmonics. Flicker. Islanding. Etc.

- Substation level:

- Voltage control.

- Global active power controls: Frequency, others.

- Protections. Harmonics. Flicker. Islanding. Etc.

CONCLUSSIONS

AWP Grid Voltage support :

AW1500 and AW3000 Turbines:

Improved LVRT / HVRT behavior.

Extended Reactive Power range.

Substation: Accurate and reliable hardware and controls

(improved close future solutions, R&D benefits).

Acciona WindPower commitment to demonstrate Full Grid

Code compliance through real and accredited field testing.

THANK YOU SO MUCH FOR YOUR ATTENTION

• Contact Email:

oalonsosadaba@acciona.es

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