Analysis and simulation of push-pull three level AC/AC converter with high frequency link

A circuit topology of the push-pull three-level AC/AC converter with high frequency link is firstly proposed. The circuit topology of this converter is constituted of multilevel converter, high frequency transformer, output cyclic converter. The three-level push-pull AC/AC converter have the advantages such as simple topology, two stage power conversions, bidirectional power flow , high frequency electrical isolation. The circuit structure is used for transferring the unstable ac voltage with high THD into a regulated constant frequency sinusoidal voltage. The converters lay the key technical foundation on new-type electronic transformers, regulated sinusoidal ac power supplies and ac regulators. The operation modes, steady principles and control strategy of the proposed converter are investigated in the paper and the converter's normalized output characteristics are given. The conclusion that the filter and the main switch voltage stress reduce can be drew. The correction and advance of the kind of converters are verified by PSPICE simulation.