Real time simulation and experimental validation of active power filter operation and control

Nonlinear loads inject harmonics into electric power systems distribution network, which deteriorate power quality and affect the sensitivity of connected electronic equipment. Shunt active power filter (APF) is an important piece of depolluting equipment that is used in power systems to cancel current harmonics, compensate reactive power and balance supply loads. In this paper an APF setup is studied and analyzed using RT-Lab real-time simulator and controller. A simple control method is used to extract the harmonic contents of the supply currents. The pulse width modulation (PWM) technique is therefore applied to command the power switches to generate the reference current for the APF. Experimental results validate the real time model and the control method is used to properly compute and track the reference current, results show efficient filtering of the load harmonics and load balancing is also successfully achieved.