Natural Sampling SVM-Based Common-Mode Voltage Reduction in Medium-Voltage Current Source Rectifier

Abstract

Conventional space vector modulation (SVM)-based common-mode voltage (CMV) reduction in medium-voltage (MV) current source rectifier (CSR) cannot be used in practice. Conventional SVM contains high-magnitude low-order harmonics, particularly the fifth and seventh harmonics, that are lying closely to the resonance frequency (4.5–5.5 p.u.) of the LC filter of the converter, thus, introducing resonance as the grid-side damping is small. Recently, a natural sampling SVM (NS-SVM) with superior low-order harmonics performance has been proposed for MV CSR. On this basis, a NS-SVM-based CMV reduction method is proposed for MV CSR in this paper. The proposed scheme achieves both good CMV reduction and superior low-order harmonics performance simultaneously. Additionally, effort to lower computational burden on calculating dwell times is made. Experiments are finally provided.