A novel zero-voltage switched multiresonant converter

A novel approach is presented by which the switching frequency of a two-transistor zero-voltage-switched multiresonant converter (ZVS-MRC) is controlled in proportion to input voltage changes in order to maintain essentially constant efficiency over the input voltage range with a switching variation of only ±10%. It is shown that a buck topology constant frequency (CF) ZVS-MRC can be accurately modeled using a spreadsheet-hosted design aid on a personal computer. Guidelines are presented for designing a buck CF ZVS-MRC, and component values are determined using the computer design aid. It is shown that if a buck CF ZVS-MRC is required to regulate over a wide input voltage range, its efficiency will be severely reduced when operating near maximum input voltage. The computer simulations are verified with experimental results