多电平逆变器在光伏并网中的建模与仿真

Modeling and Simulation of Multi-Level Inverter in Grid-connected PV System

多电平逆变器以低耐压等级的开关器件实现其中高压大功率变换,在光伏并网中得到广泛的应用。本文在传统逆变电路的工作原理和控制方法的基础上设计了一种新型2H桥级联型多电平逆变电路,以电容器作为储能单元替代部分直流电源,储存直流电源提供的和负载回馈的部分电能,并作为直流电源对负载供电。建立基于MATLAB/Simulink仿真平台下的多电平逆变电路模型,进行了仿真实验和分析。仿真结果表明,所设计电路在光伏并网系统中能够有效地提高并网逆变器效率和并网质量。

Multi-level inverter is widely used in grid-connected PV system because it can realize high power conversion in medium and high voltage with low voltage level switching devices. Based on the working principle and control method of traditional inverter circuit, a new type of 2 H Bridge Cascaded multilevel inverter circuit is designed in this paper. The capacitance is used as the energy storage unit to replace some DC power supply, and some of the electric energy provided by the DC power supply and the load feedback is used as a DC power supply to power the load. A multi-level inverter circuit model based on MATLAB/Simulink simulation platform is established, and simulation experiments and analysis are carried out. The simulation results show that the designed circuit can effectively improve the efficiency and quality of solar inverter in Pv grid-connected system.