Quasi-resonant parallel DC link circuit for high-frequency DC-AC inverters

The new simple configuration of a quasi-resonant circuit used to switch an inverters´ transistors with minimal power losses is presented. This circuit operates only at the moments of the transistors´ commutation. The additional input capacitor and a suitable simple method of system control enables bidirectional power flow and limits the overvoltage to the level 1,2÷1,3 of source voltage. The theoretical study of the process of transistors´ commutation in different possible conditions of work confirmed by laboratory investigations is the main subject of this article