基于电流内环的一种逆变器控制策略研究

Research on Control Scheme based on Current Inner-loop for Inverter Supply

比较了几种电流内环控制的方法,提出了基于电感电流反馈的SPWM电流控制型双环控制策略。针对输出电压对电流环的交叉反馈作用,通过采用电容电压解耦方法,削弱了电容电压对内环的影响;针对负载电流扰动对电压外环的影响,采用负载电流前馈补偿方法,很大程度上增加了系统对负载电流扰动的抑制能力;针对电压外环的PI调节器存在的相位滞后,提出了基准电容电流前馈补偿方法,理论上达到输出电压与基准正弦给定的零相差。通过仿真和实验,证实了本控制方案的可行性和优越性。

Several current-mode inner loop control schemes were discussed,then a SPWM current-mode dual-loop control method based on inductor-current feedback was presented. Some compensation and decouple methods are adopted to eliminate or weaken the influence on the control loop induced by certain disturbance. In order to improve the digital system′s real-time and robustness,state-observer was established based on the average state space transfer function. Simulation analysis and experimental results demonstrated the feasibility and advantages of the scheme presented.