Control Method for APF Hysteresis-band Current Tracking Based on Digital Over-sampling

An implementation method for hysteresis-band current tracking for active power filter(APF)based on digital oversampling is proposed,which enables precise compensation of harmonic current and stabilizes the switching-frequency.This method can meet different dynamic response demands of control and operation modules by utilizing different extraction factors of digital chip over-sampling.And it fully coordinates two kinds of operations in the digital signal processor(DSP),the sampling interrupt operation and main loop operation,which ensures real-time harmonic current detection and synchronous tracking for the compensating current.The same reference will be tracked N times and the change of power switching device status depends only on the parameters of the preceding switching-period,resulting in high precision tracking for current.Compared with the traditional hysteresis-band current control method,the proposed method has the advantage…