电流双环控制的LCL单相并网逆变器逆变研究

Research of single-phase grid-connected inverter with LCL filter based on current double-loop control

详细分析了LCL型单相并网逆变器的结构,针对LCL型单相并网逆变器易发生谐振的问题,研究采用以电容电流为内环、并网电流为外环的双电流环控制策略。设计LCL滤波器和电流双环控制参数并利用SISOTOOL工具整定。通过SIMULINK搭建仿真模型,分析结果表明LCL型单相并网逆变器系统在采用该电流双环控制策略可有效抑制系统振荡,降低并网电流谐波含量和提高系统稳定性。

Being aimed at the problem of LCL-type single-phase grid-connected inverter prone to resonance, the structure of LCL filter inverter was analyzed and the control strategy with grid current feedback and capacitor current feedback of current double-loop control were researched. The LCL filter and current double loop control parameters were designed, and the PI control parameters were verified and adjusted through using sisotool. The simulation model was built by Simulink. The simulation results show that the LCL filter inverter by using current double-loop control strategy can eliminate the resonance,reduce the harmonic content and improve the system stability.