A nonconventional multilevel inverter for active power filtering using unified constant-frequency integration control

Abstract

Nowadays, the increase in nonlinear loads has contributed to the generation of harmonics in the source current which in turn causes low power factor and disturbance in the power system. Active power filters (APFs) are known to provide one of the solutions to this harmonic related issue. Various types and configurations of APFs and control have been reported in literature. This paper proposes the integration of a single-phase nonconventional multilevel inverter known as the multistring Cross-Connected Source Multilevel Inverter (CCSMI) and a modified Unified Constant-Frequency Integration (UCI) controller as an active power filtering system. The results of the simulation work conducted on the proposed APF system have revealed its capability to effectively mitigate the source current harmonics with added advantages in terms of less parts counts and losses as well as reduced control complexity without the need for reference current generation.