基于复合预测的无差拍谐波电流跟踪控制

Dead-beat harmonic current tracking control method based on mixed prediction

针对传统的无差拍谐波电流跟踪控制受信号采样、处理和执行等过程时延影响,实际上是差一拍控制的问题,提出了一种基于复合预测的无差拍控制。该算法提前2个采样周期预测出谐波补偿参考电流,提前一个采样周期预测出逆变器输出电流,从而实现"真正意义上"的无差拍控制。为此,又提出了一种综合地考虑了负载谐波电流稳态和动态过程的复合预测方法,使上述预测过程更加准确。最后,仿真和实验表明基于该复合预测的无差拍控制方法在负载稳态和变化时都具有良好的补偿效果。

Aiming at the problem that conventional dead-beat harmonic current tracking control is affected by the signal sampling, processing and executing, and it is actually a one-step-delay control, a dead-beat harmonic current tracking control method based on mixed prediction is proposed in this paper. The control method predicts the harmonic compensation reference current two sample periods in advance with respect to the measurement instant and predicts the inverter output current one sample period in advance ; and then the ＂real＂ dead-beat control is achieved. A mixed prediction strategy is also proposed, which considers both the steady and dynamic processes of the load harmonic current, and makes the above prediction process more accurate. At last, simulation and experiment results prove that the proposed dead-beat control method based on mixed prediction can effectively compensate the load haimonic current both in steady and dynamic conditions.