The phase-controlled class-D ZVS inverter with current protection

This paper proposes the phase-controlled class-D inverter with resonant-capacitor voltage clamp. By adding the clamp circuits to resonant capacitances connected in parallel, it is possible to protect the inverter from the inrush and over currents automatically. By regenerating the clamp current to the input voltage source, high power-conversion efficiency can be achieved. Additionally, the design procedure with ensuring the ZVS operation in the entire control range is shown, which is achieved by numerical design procedures. It is shown from the experimental results that the proposed inverter was suppressed the over current effectively and the ZVS could be achieved at any control situations. The experimental results agreed with numerical predictions quantitatively, which denoted the validity and credibility of the design procedure with guaranteeing the ZVS.