永磁直驱风力发电系统的低电压穿越控制策略

针对永磁直驱风力发电机组的低电压穿越运行问题,对传统的控制策略进行改进,机侧增加功率前馈控制,根据机侧与网侧的功率差快速调节机侧有功电流的给定值从而控制发电机的转矩,实现对发电机输出有功功率的控制。网侧变流器对电网电压进行跟踪,根据跌落程度向电网输出一定的无功能量来支持电网电压的恢复。经仿真表明,所改进的控制策略能够快速稳定直流母线电压,实现风电机组低电压穿越运行。

Low Voltage Ride through Control Strategy for Permanent Magnet Direct-drive Wind Power Generation System

In view of the problem of low voltage ride through of permanent magnet direct-drive wind power generation system, this paper improves the traditional control strategies, and increases power feed forward control in the machine side, according to the power difference of between the motor and the grid side to adjust motor-side active current quickly to control the torque of the generator, which achieves active power control of the generator.Grid-side convert-er tracks the grid voltage, outputs a constant reactive power according to the dropped level of the grid voltage to sup-port grid voltage recovery.The simulation showed that, the improved control strategy can stabilize the DC bus voltage quickly, which can achieve low-voltage ride through operation of wind turbines.