A simple current control strategy for four-leg direct Matrix converter

A four-leg Matrix converter is built based on conventional Matrix converter. It is required to provide a path for the zero-sequence load current when the added midline bridge connects the neutral point of load. In this paper, a model predictive control method for a four-leg matrix converter under unbalanced load condition is described. The predictive control method is based on the optimal selection among the valid switching states of the converter by evaluating a cost function. Compared with the conventional method, the predictive control method is simple to implement without coordination transformation and duty ratio calculation. To support the theoretical analysis, the feasibility and reliability of the proposed method are verified by simulation results.