基于LCL型输出滤波器的多并网逆变器系统的反谐振、谐振机理分析

Anti-resonance and Resonance Mechanism for Multi Grid-connected Inverter System Based on LCL Output Filter

为有效、经济地减少开关谐波以满足日益严苛的并网条件,LCL型输出滤波器业已成为电压源型脉冲宽度调制(pulse width modulation,PWM)逆变器的标准配置,但长导线、大漏感和电容器等所形成的复杂配电网环境对基于LCL型输出滤波器的多并网逆变器系统的反谐振、谐振问题影响极大,为此,建立单个、多个并网逆变器的系统模型;借助Bode图获取反谐振、谐振频率;分析不同配电网环境下,基于LCL型输出滤波器的多并网逆变器系统的交互作用。实测结果验证了理论分析的正确性。

For effectively and economically reducing switch harmonic in order to satisfy continuously rigorous grid-connection condition,LCL output filter has become a standard configuration for voltage source pulse width modulation inverter.But for reason of complicated power distribution network environment formed by long conductor,big leakage inductance and capaci-tor,it may cause great impact on anti-resonance and resonance of multi grid-connected inverter system based on LCL output filter.Therefore,this paper introduces establishment of single and multiple system models for grid-connected inverter.With the help of Bode figure,anti-resonance and resonance frequency is able to be acquired.In addition,this paper analyzes inter-action of the multi grid-connected inverter system based on LCL output filter under different power distribution network en-vironment.