非并网风力发电系统的电压协调控制

Coordinated Control of Voltage in Wind Power System Without Grid Connection

在非并网风力发电系统中,当风能突然增加或负载突然减少时,系统的功率平衡将被打破,从而造成直流电网中出现电压尖峰和电压升高,可能造成系统中功率器件的损坏。文中通过改变负载电流、输电线电压或注入电网电流等参考值,从而改变从直流电网吸收或向直流电网注入的电流值,抑制了电压尖峰和电压升高。仿真分析结果表明该控制方法能够起到很好的抑制作用。

When wind power increases or loads decrease abruptly in wind power system without grid connection, the power unbalance will occur, which will cause voltage spikes and voltage increase so that the power electronics devices in the system may be damaged. The voltage spikes and voltage increase may be restricted by changing the current drawing from or injecting to the DC grid through the changes of references for load current, bus voltage or injected current. The simulation results verify the performance of the method proposed. This work is supported by Special Fund of the National Basic Research Program of China （No. 2007CB210303）.