一种简单的预测电流控制新方法

为提高有源电力滤波器(APF)的电流跟踪性能,提出一种简单的预测电流控制新方法。该方法在当前采样时刻预测下一采样时刻参考电流值,计算出APF在下一采样时刻输出端参考电压值,再利用电压空间矢量调制得出控制开关信号,以达到电流跟踪控制目的。稳态时,利用前一周期存储的参考电流历史数据预测下一采样时刻参考电流值;暂态时,利用二阶外推插值法得到下一采样时刻参考电流值。该控制方法可以消除采样、计算等带来的延时,有效降低开关频率波动范围,具有电压利用率高、开关损耗小、动态响应快的优点。仿真与实验结果证明了该方法的正确性和可行性。

Simple method of predictive current control

In order to improve the current tracking performance of APF(Active Power Filter),a simple predictive current control method is proposed,which predicts the current reference of next sampling instant at current sampling period,calculates the voltage reference of next sampling instant for APF,and then obtains the corresponding switching signals by voltage space vector modulation to realize current tracking control.In stationary state it uses data collected in previous period to predict next current reference while in transient state it uses two-order extrapolation,which eliminates the delay caused by sampling and calculation and effectively lowers the switching frequency,with high voltage utilization factor,low switching loss and fast dynamic response.Simulation results show the proposed method is valid and feasible.