ABSTRACT

Impedance Source Inverter (ZSI) offers a solution to low output renewable energy sources, provides unconventional high boost. Interaction of Quasi-Z-Source Inverter (qZSI) and third order filter raises stability concerns. Dynamic interaction of DC and AC sides shows additional resonant frequencies, resonant characteristic needs attention when grid connected. In this paper, resonant characteristic of a third order passive filter based qZSI is explored. DC and AC sides dynamic model are analysed considering parasitic resistance, and optimum parameter selection for passive component and controller design is presented. Closed loop stable control is established for input variation taking care of multiple resonant feature. Disturbance rejection for an increased and decreased input is established by DC and AC side controllers, DC and AC side dynamics are handled using voltage loop and dual current loop, respectively. MATLAB/PSIM/dSPACE 1104 are used in this study, controller response is evaluated for two design cases (case I, II) and recommendations are made considering resonant characteristics, measured results validate the design and control methodology.

摘要

阻抗源逆变器 (ZSI) 为低输出可再生能源提供解决方案，提供非常规的高升压。准 Z 源逆变器 (qZSI) 和三阶滤波器的相互作用引起了稳定性问题。直流侧和交流侧的动态相互作用显示出额外的谐振频率，并网时需要注意谐振特性。在本文中，探讨了基于 qZSI 的三阶无源滤波器的谐振特性。分析了考虑寄生电阻的直流侧和交流侧动态模型，提出了无源元件和控制器设计的最佳参数选择。为输入变化建立闭环稳定控制，同时兼顾多重谐振特性。增加和减少输入的干扰抑制由 DC 和 AC 侧控制器建立，直流侧和交流侧动态分别使用电压回路和双电流回路处理。本研究中使用了 MATLAB/PSIM/dSPACE 1104，评估了两个设计案例（案例 I、II）的控制器响应，并在考虑谐振特性的情况下提出了建议，测量结果验证了设计和控制方法。