APresentation

on Impacts of Large Scale Wind Plants On Power System

Transient Stability

Academic Session 2012-13

Guided By:- Submitted by:-Mrs.Nikita Jhanjariya Arvind SiddhAssociate Professor M.Tech- Ist sem. power system

Malviya National Institute Of Technology

CONTENTS

• Objective• Issues for wind plant studies• Impacts on stability• Wind mill modelling• DFIG Technology & aggregated wind farms• Transmission model for analysis• Transient stability analysis• Conclusion• Vote of thanks

OBJECTIVE

• To study about various issues and impacts of wind plants on power system stability

• Analysis about various generator technologies• Transmission model and it”s analysis for

transient stability phenomena

ISSUES FOR WIND PLANT STUDIES

• Fluctuating nature of windpower• Location of wind resources• Various generator technologies generator

control• Superposition of various wind power aspects• Predict required network reinforcements • Additional reserve requirements• The impact on power system stability

IMPACTS ON TRANSIENT STABILITY

• Differ location of wind resources• Various generator technologies• Connection at lower voltage levels• Fluctuating nature of wind power

Wind mill modelling

• Wind turbines constitutes of various technologies

• a) fixed speed induction generator• b) variable speed induction generator(DFIG

technology)• c) Aggregated wind farm technique

DFIG Technology

• DFIGs are variable speed wind turbines• Hence they provide a constant frequency

electrical output for varying wind speeds• This is accomplished by power electronics

Circuit structure

Transmission model

Transient stability analysis

Cases for analysis • a) base case• b) changed location of generation• c) DFIG technology• d) 100 % DFIG• e) Infeed at lower voltage level

Base case

• Normal operation of system without an wind power

• Area 1 generators highly affected by fault

• Importing of power from area 3

Changed location of generation

• Adding of extra generator to area 1

• Now area 1 exports the electrical power

• Rotar angle difference increases

• System closer to stability limit

DFIG technology

• Half generation is modelled with DFIG

• Reactive power flow remains same o case 1

• Transient network stability increses

100 % DFIG

• Full generation is through DFIGs instead of SGs• Volatage control is appliedand system not

encounters the transient stability limit

Infeed at lower voltage level

• Wind generation is connected to sub-transmission level• Reactive power contribution is lowered• Critical fault clearing time is reduced

Conclusion

• The location of wind generators can have a very large im-pact on transient stability.

• DFIG improves the transient stability margins• Integration to subtransmission distribution

system have negetive impact on transient stability

Thank you