基于重复和准比例谐振复合的直驱风机网侧变流器控制策略

为了提高电网电压不平衡及畸变条件下永磁直驱同步风电机组的运行性能,提出了一种基于重复控制与准比例谐振控制复合的直驱风机网侧变流器控制策略。该控制策略根据电网电压不平衡条件下变流器控制目标得到电流指令值,在两相静止坐标系下利用复合控制,实现对基频电流的无静差跟踪,并抑制交流电网谐波的干扰。在提出控制系统详细框图的基础上,对各个控制环节的设计方法进行了研究,并评估了控制效果。仿真结果表明,该控制策略在电网电压不平衡及畸变的工况下,能有效抑制有功功率波动,降低电流谐波畸变率,验证了策略的正确性。

A control strategy combining repetitive control and quasi-PR control for PMSG grid-side converter

In order to improve the performance of the Permanent Magnet Synchronous Generator (PMSG) under unbalanced and distorted gird voltage operating conditions, a novel Control Strategy Combining Repetitive (REP) control and Quasi-Proportional Resonant (QPR) control is proposed for PMSG grid-side converter. In the proposed control strategy, the current commands are dependent on the objectives of converter control when the grid voltage is unbalanced. The hybrid control strategy is applied in the two-phase stationary reference frame to eliminate the steady-state tracking error on the fundamental frequency current and suppress the total harmonic distortion. The block diagram of control system is presented, and the design methods of each block are studied. Meanwhile, the effect of the control strategy is investigated. Finally, the simulation results show that the proposed control strategy can effectively suppress active power pulsation and reduce the total harmonic distortion under unbalanced and distorted gird voltage operating conditions, verifying the correctness of the strategy.