考虑变直流母线电压参考值的直驱风电机组高电压穿越控制策略

A high-voltage ride through control strategy for PMSG based wind turbines considering variable DC voltage reference value

针对风电机组高电压脱网问题,提出了一种考虑变直流母线电压参考值与网侧无功优先控制相结合的HVRT控制策略。该策略在电压轻度骤升时,通过优化无功电流给定值,快速向故障电网注入感性无功电流;电压深度骤升时,改变直流母线电压参考值,抑制直流侧电压波动。最后,在Simulink中搭建了1.5 MW直驱永磁风电机组仿真模型,在不同电压骤升幅度下对文章所提控制策略进行验证,结果表明,该控制策略能在不同电压骤升幅度下实现机组的HVRT,且避免Chopper电路的频繁动作,提高了机组稳定运行的能力。

In research of tripping of wind turbines under high voltage conditions, the requirements of the newest grid integration guide for wind power to high voltage ride through(HVRT) are introduced. Based on an analysis of the influence of grid voltage swell toward direct drive wind power system, a comprehensive HVRT control strategy combining both the DC bus voltage reference value and the reactive power priority control of the network side is proposed. According to the latest standard of connecting grid, inductive reactive current is injected to grid by optimizing reactive current instruction under mild swell, while reference value of DC bus voltage is changed for the p.u.rpose of restraining fluctuation of DC side voltage under deep swell. A 1.5 MW D-PMSG model is built in matlab/simulink, and both traditional control strategy and the paper proposed control strategy is simulated and analyzed. The simulation results show that such a strategy can realize HVRT at different cases of voltage swell amplitude and avoid the frequent action of the chopper, improving the stable operation ability of unit.