基于小扰动稳定分析的并网直驱永磁风电系统建模优化和仿真

Modeling Optimization and Simulation of Grid-connected Direct-Driven Permanent Magnet Wind Power System Based on Small Signal Stability Analysis

风力等各类逆变型电源的接入增加了电力系统扰动的概率和不确定性,而传统的基于电磁暂态的仿真分析无法很好地解决逆变器控制策略问题。应用小干扰稳定分析,研究了永磁直驱风力发电机接入无穷大电网的稳定性问题,建立了完整的风力发电系统小扰动模型,包括风轮机、永磁同步发电机、AC/DC控制器、L型滤波器、DC/AC控制器和直流侧电容器。用特征值分析法分析风力发电系统的小干扰稳定性,在PSCAD/EMTDC中搭建了完整的仿真模型,对风速突变的情况进行仿真,验证了小扰动建模和分析的正确性。

Power system stability problem has always been the focus of attention. The various signals are likely to produce impacts on power system. The connection of inverter sources such wind generation to power system increases the probability of disturbance and uncertainty. The traditional simulation methods based on electromagnetic transient cannot solve the problems in inverter control strategy. This paper employs the small-signal stability analysis to study the power system stability problem when direct-driven permanent magnet wind power generator is connected to infinite grid. The small-signal model was built,including wind turbine,permanent-magnet synchronous wind generator,controller for AC / DC inverter,L-shape filter,controller for DC / AC inverter,and DC-link capacitor. Its small-signal stability was analyzed by means of eigenvalues analysis. The simulation model was built based on PSCAD / EMTDC for simulating wind velocity mutation,which verifies the correctness of the small-signal modeling and analysis.