A new SVPWM for phase currents reconstruction of three-phase three-level T-type converters

Abstract

This paper presents a new space vector pulse width modulation(SVPWM) scheme to reconstruct phase currents using neutral point current sensing in three level T-type converters. For this purpose, zero vectors and offset vectors are replaced with complementary active vectors. These active vectors do not affect the resultant output voltage and the voltage balance at the neutral point of three-level T-type converters. Hence, the pulse widths of corresponding active vectors can be adjusted even at low speeds without additional switching losses and low frequency noise in the inverter. The modified switching patterns can easily be created without significant computational complexity. The proposed method is experimentally verified using Fuji T type IGBT modules, Texas Instruments TMS320F28335 and Spartan 6 systems.