Five step-low frequency switching active power filter for networkharmonic compensation in substations

摘要

This paper presents the performance evaluation of an active powernfilter that uses a five-step current source inverter. The use of anmulti-step inverter implies lower frequency switching, thereby allowingnthe introduction of higher power switching devices. The control filternuses a frequency domain approach in which line current harmonics arenextracted using an FFT routine. A compensating current related to thenharmonic components of the load current is generated. This compensatingncurrent is injected at the point of common coupling to cancel the loadncurrent distortion. The algorithm used to generate the compensatingnfunction is presented and the system's ability to reduce currentnharmonics with lower frequency switching is demonstrated throughnsimulations and a low power prototype