离网逆变器负载电流直接前馈控制方法的研究

Research on Load Current Direct Feed-forward Control Method of Off Grid Inverter

对于离网运行的逆变电压源,控制的目标是在任意类型的负载条件下保证输出电压的质量。在常见的滤波电容电压外环、滤波电感电流内环控制结构的基础上,提出一种基于负载电流直接前馈的控制方法,来有效抑制负载扰动及非线性负载对输出电压的影响。同时,在分析该控制结构离散化数学模型的基础上,分析了负载电流直接前馈环节中的微分参数对输出电压的影响。最后,通过仿真与试验波形验证了所提控制方法的有效性。

For off-grid inverter,the control target is to ensure the output voltage quality with all kinds of load. A kind of control method was presented based on direct load current feed-forward to avoid the influence of load disturbance and non-linear load on the output voltage,which on the basis of filter capacitor voltage outer-loop and filter inductor current inner-loop. And then,based on the analysis of the discrete model of this control structure,the influence of load current feed-forward differential coefficient on the inverter output voltage was analyzed. Lastly,this control method is validated by the simulation and experiment.