Three-phase bipolar mode active power filters

In this paper, a unified constant-frequency integration control method for a three-phase bipolar mode active power filter is proposed. The proposed control method eliminates the use of any multipliers, the need of sensing three-phase load current, and the nontrivial task of calculating the harmonies and reactive current components, as required by previously reported control methods. By applying one-cycle control and sensing the mains line current, unity power factor and low input current distortion can be realized by one integrator with reset along with a few linear components such as flip-flops, comparators, and clock. The proposed controller is simple, robust, and reliable. All findings are supported by simulation and experiments.