A strategy of neutral-point potential balancing control for threelevel indirect matrix converter

According to the three-level neutral-point potential balancing problem of three-level indirect matrix converter (TLIMC), a virtual space vector modulation strategy was firstly introduced in TLIMC in solve this problem, which hasn´t yet been discussed today. This modulation strategy is divided into two control stages. Space vector PWM without zero vectors is used for rectifier stage. The modulation method for inverter stage based on the virtual space vector concept only requires the condition that the flow of neutral-point current equals zero, so the neutral-point balancing problem of this topology is effectively settled. Finally, the validity and feasibility of this modulation method are tested by simulation and experiment; the result indicate that TLIMC with the modulation strategy produces better output performance in terms of reduced harmonic content. Also, the converter is also able to maintain sinusoidal input currents guaranteeing the balancing of neutral-point potential over the full range of output voltage. This paper main contribution is to solve the neutral-point balancing problem for three-level indirect matrix converter (TLIMC) using a virtual space vector modulation strategy.