Implementation of improved pq theory in shunt active filter based on cascaded multilevel inverter with single excited DC source

In this paper, a Cascaded H-Bridge Multilevel Inverter (CHBMLI) is proposed and designed with single dc source employing single-phase transformers to operate as a shunt active filter for harmonic reduction. The paper studies the complete architecture and control logic of the proposed multilevel inverter. For harmonic current extraction an improved instantaneous active and reactive power control technique is used for reference current generation. Phase shifted PWM technique is used for the modulation of CHBMLI. Finally a seven level CHBMLI is developed to operate as a shunt active filter. The proposal and performance are validated through simulation results.