Research On Reactive Power Compensative Control Strategy Of Power System Including Large-scale Wind Power Farm

In the large constant frequent wind power generation system, doubly-fedinduction generator accounted for a large proportion. It can realize the maximumcapture of wind energy and has the flexible ability of reactive power regulation. Butwhen the grid gets large disturbed, the ability will be close to saturation and theability of resisting voltage drop will abate. So we need to take some measures toensure continuous and stable operation of the wind farm. In view of the problem ofreactive power compensation for doubly-fed wind power generator, this article willcarry out a series of analysis and research. Through the analysis of the currentseveral kinds of reactive power compensation devices, the paper will put forward ajoint reactive compensation strategy to maintain voltage stability and satisfy thedemands of wind power grid.At first, the paper will study the working principle and mathematical model ofdoubly-fed wind power generator. Taking an actual wind farm for example, the paperhas carried on the simulative research for the steady state and transientcharacteristics of doubly-fed wind power generator application using MATLABsimulation software.Secondly, the paper will study the mathematical model and operationcharacteristics of SVC and STATCOM and put forward to the corresponding controlstrategy of the two kinds of reactive power compensation device respectively.Combining a regional power grid, both SVC and STATCOM will be applied to thewind farm and will analyze the characteristics of network voltage. The simulativeresults show that both the SVC and STATCOM can help wind farm voltage rapidlyreconstructed after the fault. In addition, the STATCOM can better improve thetransient stability of the wind farm and the compensation effect of STATCOM isbetter than SVC.At last, the paper will put forward a joint reactive compensative strategy ofparallel capacitor+STATCOM. Taking two doubly-fed wind farms as an example, thepaper will analyze the output characteristics when a three-phase short-circuit faultand a single-phase grounding fault in the power system occurs. The results show thatthe joint reactive compensation strategy can effectively improve the wind farmexports and node voltage level. The method provides an effective and economic compensation strategy for the selection of wind farm reactive power compensationdevice.