Grid Compatibility for Large-Scale Photovoltaic and Wind Power Systems.

OBJECTIVES

Student(s): Anshuman Vaidya, ECE Department

BACKGROUND

• Increasing penetration of renewable sources weakens the grid because of intermittency.

• Ancillary support is needed to counter large penetrations.

• Renewable energy sources like WPP and PVP have untapped capability to support the grid by voltage and frequency regulation.

• Capability of a PVP or WPP system can be analyzed and matched according to the need.

PhotoVoltaic Plant (PVP) System

Faculty Advisor(s): Dr. Badrul Chowdhury, Dr. Jonathan Kimball, ECE Department

APPROACH

• First the Maximum Power Point is tracked for the given amount of available Solar power.

• Then the system is operated at point slightly lower than the MPP so as to provide a control over a control over the active power production.

• Power converters used in the system can provide/absorb reactive power as and when needed.

APPROACH

• Determine the wind speed in the area and calculate the maximum power that can be captured by the wind turbine.

• Keep the pitch angle as low as possible abiding the rpm limit of the motor.

• Calculate various parameters like TSR(λ), Cp(λ,β).

• Determine the Active and Reactive power capability of the DFIG used by identifying it’s machine parameters and rated operating values.

RESULTS

Wind Power Plant(WPP) System FUTURE WORK

• Active and reactive power capability information of renewable power plant would help the plant operator to take an informed decision at the time of crisis.

• Converter control techniques would be developed in the later stages of this work which would help in frequency and voltage regulation of the grid.

• In this project, new converter control techniques will be developed to improve grid compatibility of solar photovoltaic plant (PVP) and wind power plants (WPP).

• The aim is to enable PV and wind power systems with voltage and frequency regulation capability by providing active and reactive power reserves in PVP and WPP.

• One objective is to determine the max available active and reactive power of PVP/WPP and the associated capability curves.

PV ARRAY

Boost Converter

Single Phase Inverter

GRID

MPPT Control

InverterControl

Ipv

Vpv

Duty Cycle Vgrid

Igrid

DC Bus voltage error feedback (Iref)

Gate Signals

DC BUS CAPACITOR

Absorb active/reactive power when surplus & deliver when needed.

G1

Bus 1

Bus 2

Bus 3

Bus 5

Bus 4

Bus 6

Load 3

Load 1

Load 2

Win speed14 m/s12 m/s

010

2030

4050

60

0

5

10

15

20

250

0.5

1

1.5

2

2.5

3

Wind Turbine Speed (RPM)Pitch Angle (Deg)

Po

we

r O

utp

ut (

Wa

tts)

Power output curve vs Pitch angle and Speed

Active and Reactive Capability Curve with different wind speeds

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-1.5

-1

-0.5

0

0.5

1

1.5

Active Power (p.u.)

React

ive P

ow

er

(p.u

.)

Wind Turbine Capability Curves for different wind speeds.

9 m/s

10 m/s

11 m/s

12 m/s

13 m/s

14 m/s

DFIG

Acknowledgements

We gratefully acknowledge the support of Intelligent Systems Center .