基于等脉宽调制的分布式光伏发电逆变装置的仿真分析

Simulation Analysis on Distributed Photovoltaic Power Inverter Device Based on Pulse Width Modulation

逆变器是分布式光伏发电系统的重要组成部分,为了得到更好的正弦交流电,减小其谐波含量,建立了基于等脉宽调制的分布式光伏发电逆变装置,讨论了等脉宽调制的原理及其计算方法,研究了不同占空比下的输出电压和电流的波形,通过MATLAB仿真软件分析了输出电压和电流的谐波特性.仿真结果表明,利用等脉宽调制方法得出的输出电压和电流的谐波较小,等脉宽调制逆变电路的谐波特性优于PWM脉宽调制逆变电路.

The inverter is an important part of the distributed photovoltaic power generation system. To get a better sinusoidal alterna- ting current and smaller harmonic content, a distributed photovohaic power inverter device based on pulse width modulation is built. Then the principle and calculation method of pulse width modulation are discussed. The output voltage and current waveforms under the condition of different duty cycles are studies. The harmonic characteristics of output voltage and current are analyzed by using MATLAB simulation software. The simulation results show that the harmonic of output voltage and current obtained by the pulse width modulation method is smaller. By comprehensive comparison, a conclusion can be drawn that harmonic characteristics obtained by pulse width modulation inverter circuit is better than that by the PWM pulse width modulation inverter circuit.