针对不对称电网故障下,双馈风力发电机的控制策略进行了研究。讨论了电网故障时转子侧变流器(RSC)和网侧变流器(GSC)的控制目标,合理安排了电网严重故障时的控制优先级。基于比例-积分-谐振滑模控制原理设计了机侧和网侧变流器协同控制方案。通过MATLAB/Simulink仿真软件搭建了所设计控制方案的仿真模型。仿真结果表明,在电网正常运行的情况下,与传统的矢量控制策略相比,比例-积分-谐振滑模控制策略对输出功率、电流变化的响应更迅速,具有更好的动态性能和抗扰动能力；在电网不对称故障下,能够有效地抑制电磁转矩振荡和直流母线电压波动,提高了双馈式风力发电机的低电压穿越能力。

A coordinated control strategy of rotor side converter (RSC) and grid side converter (GSC) based on proportionalintegralresonant sliding mode controller (SMC) was presented. First, the control objectives and priority of RSC and GSC were analyzed under different levels of grid faults. Then, the proportionalintegralresonant sliding mode controllers of RSC and GSC were respectively designed to eliminate the tracking error of ac component and improve the dynamic performance and disturbance resisting ability. At last, a simulation was conducted to verify the effectiveness of the designed control scheme under different asymmetrical grid faults.

TM 301.2

新能源电力系统国家重点实验室开放课题(LAPS16023)