Cancellation of the output ripples of a three-phase converter using parallel-connected inverters and phase-shift-self-oscillating controllers

This paper deals with controls of a converter, where two paralleled-inverters are used. One inverter acts as a master unit and the other one acts as a slave unit. Thanks to these controls, an accurate tracking of the references is got and the output voltage ripples are lowered. As the goal is not to expand the system capacity, the slave unit delivers the currents to the load and becomes the power source meanwhile the master unit is in charge of the output voltage regulations. Thus the master unit compensates the ripples of the slave module output currents. In order to understand the proposed strategy, it is necessary to start with the operation of the Phase-Shift Self-Oscillating controllers. Then the operation of the paralleled-inverters is explained and a model of the power circuit is investigated. Simulations and experiments confirm the high performances in terms of ripples rejections.