Design Of Dc/dc Converter With Single Phase Inverter Load

With the application of inverter is getting more and more widely,the research of inverter is also getting more and more attention.In some application,a dc-dc converter is needed to boost the input voltage to a level that can be converted to the desired ac output and to achieve the purpose of electrical isolation. Due to non-linear time-varying characteristic of a single phase dc/ac inverter, its front-end dc/dc converter tends to draw an ac ripple current at twice the output frequency, which may shorten battery life span.In this paper ripple generation mechanism is investigated with low frequency input characteristic of a single phase inverter at first,and then back current gain transfer function Ai(s) is firstly proposed to evaluate input current ripple cancellation effect of the front-end converter with different control schemes, which could explain why average current mode control scheme is better than voltage mode and open loop control strategies in input current ripple cancellation aspect, while the latter two are of no effect in this field. Following the guideline, a prototype combined of a push-pull-forward converter and half bridge double buck inverter is built and tested for input current ripple cancellation evaluation.Based on the method of back current gain transfer function,a new method is also proposed for analysis of the current stability problem in this paper,which is named inductor current gain transfer function. These two transfer functions are used to guide the design of DC/DC converter.