Novel Current-Tracking Control for Hybrid Active Power Filter with Injection Circuit and Its Engineering Application

A novel type hybrid active power filter with injection circuit (IHAPF) is proposed. The passive filter of this system can be used for reactive power compensation as well as for harmonic mitigation. The active power filter does not bear fundamental voltage any more. A new sliding-window iterative algorithm based on discrete fourier transform (SWIDFT) is proposed for detecting harmonic current. Recursive integral PI regulator ( RIPI) is adopted in current closed-loop controller and this control method can eliminate steady-state error. Fuzzy algorithm is used to adjust the coefficients of RIPI online. Results of industrial application show that the proposed control and detection methods in this paper can meet the requirement of IHAPF controller. After IHAPF with the proposed controller is run, the total harmonic distortion (THD) of supply current is reduced to 1.8% from 41.8 % and the power factor of the system is increased to 0.95 from 0.55.