A Simple Commutation Method and a Cost-Effective Clamping Circuit for Three-to-Five-Phase Indirect-Matrix Converters

This article presents and analyzes a three-to-five-phase indirect matrix converter (IMC) structure for directly supplying a five-phase static R-L load from a three-phase supply. The IMC topology offers a lower number of switches, a simple commutation procedure and a cost-effective clamping circuit in comparison to the direct matrix converter (DMC). A simple clamping circuit with one ultrafast diode and one small capacitor is proposed to protect the switches of the IMC from overvoltage. The issues of powering up the IMC with the simple clamping circuit is discussed in detail. The instructions for the safe start-up of the IMC with the proposed clamping circuit is introduced based on the simulated and the measured analyses. Moreover, a carrier-based pulse-width-modulation (CBPWM) method is also presented in order to control the switches of the IMC. The presented CBPWM method creates PWM pulses for both the inverter and the rectifier legs by using only one symmetric and triangular carrier signal. Finally, experimental and simulation testing with a five-phase R-L load demonstrate the viability and the efficiency of the introduced CBPWM algorithm for the suggested IMC.