基于变流器控制的永磁风电机组低电压穿越控制策略

Low Voltage Ride-through Control Strategy for Wind Turbine with Permanent Magnet Synchronous Generator Based on Converter Control

针对永磁风电机组低电压穿越(low voltage ride-through,LVRT)采用改变背靠背变流器控制策略的方法时,存在未考虑因转子转速越限导致机组发生超速脱网的问题,提出了基于变流器控制的LVRT控制策略。基于转子运动方程,推导了能够抑制机组转子转速越限的机侧变流器有功功率整定计算公式,设计了可降低卸荷电阻使用率的卸荷电阻投切方法,仿真结果验证了该策略的有效性。

When the low voltage ride-through(LVRT)method of changing the back-to-back converter control strategy for wind turbines with permanent magnet synchronous generator is adopted,there is a problem of not taking into account that the turbine will being tripped-off from grid at an excessive rotor speed.Therefore,a LVRT control strategy for wind turbines with permanent magnet synchronous generator based on converter control is presented in this paper.On the basis of the rotor motion equation,the setting calculation formula of the active power of machine-side converter suppressing the overrunning of the rotor speed is derived,and the switching method that reduces the utilization rate of the discharging resistance is designed.The simulation results show that the proposed control strategy is effective.