An improved four step commutation process for silicon carbide based matrix converters

This paper is conducted a brief account of the matrix converter (MC) commutation process. To satisfy requirements, the MC hardware prototype needs both proper commutation and a proper switches process. The different types of processes for suitable commutation between the phases are investigated: firstly, the overlap and dead-band approaches which have some limitations; and then two-, three- and four-step commutation processes. Their limitations are discussed which leads to the improved four-step commutation suitable for four-legs being selected. Discussion is continued on the switching devices. The switches are categorised as one or two active devices implementations. Based on the switching devices limitations, two degrees of freedom SiC MOSFET is selected for the MC commutation process. This paper is briefly discussed on the improved four step commutation process. The commutation process is explored on the basis of two- three- and four leg state machine diagrams. In the last section of this paper, the results obtained from experiments exploring Si-based MOSFETs and SiC-based MOSFETs switches using the four-step two-leg commutation process are discussed. For a more proper validation of this commutation, a DC supply-based experiment is conducted. The experimental results are also focussed on the load voltage response, where setup is developed on the four step three leg commutation MC with SiC-MOSFETs switches. The load voltage response also led the validation of proper commutation and switches for MCs distribution level voltage regulator applications.