Reverse Direction of Hysteresis Bandwidth Calculation to Fix the Switching Frequency Employed in Active Power Filter

Active power filters are used widely to eliminate the distribution system harmonics. Variable switching process is the main issue in practical implementation of fixed band hysteresis current controller in active power filters that increases the switching frequency and switching losses in power systems. Preventing this case, the Adaptive Hysteresis Current Control has been introduced and developed by many researchers. By this way, The Hysteresis Band will change adaptively by system parameters in order to control the switching speed and fix the switching frequency. In this paper a revisory method for the hysteresis bandwidth calculation procedure is proposed that makes switching frequency constant significantly. In this method a modified formula for adaptive hysteresis band is achieved. The active filter Simulations using proposed method in Matlab/Simulink environment has been done. Results including switching frequency and current source TDH have been given to prove the efficiency of this method. Key woud:Active Power Filter Hysteresis Current Control Instantaneous Power Theory Harmonic Voltage Source Inverter (VSI)