Simulation of current active power filter and its control methods

Active Power Filters is an effective means to cope with harmonic pollution in power network. This paper describes the basic operation principle and control methods of the current-source active power filter, and focusing on triangle modulation strategy of APF, detailed analysis of occurrence and distribution of the signals. When the APF load current detected includes capacitive load current, with the compensation coefficient change, the system has potential risk of resonance, affecting the stability and the harmonic compensation. Then, a control method in which both the supply current and load current are detected to control the output current of parallel active power filter is proposed. The control method makes the system work effectively when the capacitor current is included in the detected load current, and it can be easily implemented by the APF itself. The simulation results indicate that the active power filter´s stability is high and its harmonics compensation performance is excellent. Finally, simulations results are presented to demonstrate the conclusions of the proposed control method.