| Traditional three-phase voltage source PWM rectifiers and current source PWM rectifiers are the two most commonly used rectifiers in industrial and life.However,these two rectifiers can only achieve step-up or step-down output.In some cases,the output voltage need to be varied in a wide range.At this time these two rectifiers are difficult to meet the design requirements,the traditional step-up/down PWM rectifier can achieve a wide range of voltage output,but there are electrolytic capacitor in the rectifier,affecting the overall reliability and life.To solve this problem,this paper proposes a new type of three-phase electrolytic capacitor-less step-up/down rectifier.The rectifier is formed by the pre-stage circuit of the three-phase current rectifier and the Zeta circuit and reuse the switch tubes.Therefore,the rectifier cable of step-up/down voltage with single stage.In addition,all capacitors used in the rectifier are non-electrolytic capacitors,so the reliability is high and the life is longer.The rectifier can work in the Intermediate inductance curren unidirectional or bidirectional flow mode,when the rectifier operates in the current bidirectional flow mode of the Intermediate inductance,all inductors in the rectifier are small,and the power density is high.This paper first analyzes the working principle and working mode of the rectifier in detail,then mathematically deduces the buck-boost transfer ratio of the rectifier in the two modes.and designed the current inner loop PR regulator parameter and outer loop PI regulator parameter.Based on this,The closed-loop simulation verification and analysis of the new step-up/down PWM rectifier in these two modes are performed.Finally,an experimental prototype is built.The open-loop and closed-loop experiments of the three-phase electrolytic capacitor-less step-up/down rectifier are performed on the experimental prototype.The experimental results verified the correctness and feasibility of the theoretical analysis. |
PDF Full Text Request