Output voltage distortion in matrix converter by commutation of bi-directional switches

The matrix converter is an AC-to-AC conversion device without intermediate DC link and the associated large capacitive filter. Three-phase matrix converter consists of nine bi-directional switches, which allows PWM control of input and output currents. Commutation from one switch to another is important for reliable operation. During commutation sequence, unwanted output voltage distortion occurs because actual commutation is dependent on magnitude of input voltage and direction of output current. In this paper, output voltage distortion during current commutation between bi-directional switches is analyzed and effective compensation method is proposed. The feasibility of the analysis results is proved by experimental results.