电动汽车双向阻抗源逆变器分析与控制

摘要

提出一种新型双向功率流阻抗源逆变器(Z-Source Inverter,简称ZSI)拓扑结构,以有效解决ZSI在DCM模式时输出电压不可控、系统失稳的难题.详细分析了系统工作原理和PWM信号发生方式.采用开关信号流图SFG方法建立系统稳态与动态模型.并从动态小信号模型推导出系统的传递函数.分析了系统稳定性和动态特性,对两个控制变量(D,M)进行解耦.设计了双环控制器以提高系统动态性能和稳定程度.研制开发了一台55 kVA双向功率流ZSI来验证所提拓扑和控制方法的有效性,实验结果证明系统性能优良,可有效应用于电动汽车等领域.%A new topology of bi-directional Z-source inverter is proposed.It can overcome the uncontrollable and unstable limitations of the Z-source inverter in the discontinuous conduction mode (DCM).The operating principle and the way of PWM signal produced is analyzed.The system stability and dynamic performance are established by switching signal flow graph model and the transfer function for the circuit are developed from dynamic small signal.The system stability and dy-namic performance are analyzed thoroughly.Two control variables D and M are decoupled.A dual closed loop controller is proposed to improve the stability and dynamic performanee.A prototype of a 55 kVA hi-directional Z-source inverter is de-signed to verify the principle and demonstrate the performance of the proposed topology.