A family of resonant DC-link voltage source inverters

A family of circuits that can be used as interfaces between the DC voltage supply and the voltage source pulsewidth modulation (PWM) inverter to provide oscillation of DC bus voltage and allow commutation of PWM inverter switches under zero voltage is presented. A technique for reducing device voltage stresses that consists of using a nonlinear resonant capacitor is introduced. To allow the inverter to be regulated by the conventional PWM strategies, a technique is proposed which consists of interrupting the resonant cycle by an auxiliary switch. The principle of operation and a theoretical analysis of one of the topologies are presented. A laboratory prototype of a single-phase inverter regulated by PWM with harmonic elimination has been built and tested. The results of the experimental studies are reported