A novel of passive soft-switching with charge-pump snubber

A novel passive lossless snubber method called charge-pump snubber (CPS), which can improve commutating of the switching devices and regenerating of the switching transient energy, is proposed. The new snubber is comprised of an additional low power auxiliary winding magnetically coupled with the main inductor, a small inductor, two low power diodes, and two small capacitors. It can regenerate energy captured in the snubber capacitor fully and directly. It not only snubs the switching devices effectively, but also has a few good features such as wider soft-switching range, lower voltage stress, simple to design, lower cost and so on. To be a demonstration, operation principle, theoretical analyses, relevant equations, simulative results, as well as experimental testing results of a typical PWM boost converter equipped with proposed CPS are shown. All are verified that the technology is well applicable to any nonisolated DC-DC converters, especially for those want to operate under the conditions of very wider ranges of input voltage and/or load current, which still hold soft-switching operation