三相电压型逆变器的鲁棒跟踪双环控制器

Robust tracking dual-loop control of three-phase voltage source inverters

为了保证三相逆变器在负载变化及参数摄动时输出电压动态响应快、稳态精度高、波形失真率小,基于αβ模型设计一种电感电流内环电压外环的双闭环控制器。电压外环采用离散积分滑模控制以改善系统的稳态性能并增强系统的鲁棒性。进行了正弦波跟踪的仿真实验,结果是突加纯阻性负载时调整时间为2m s,暂态过程中输出电压总谐波畸变率为3.46%;当参数缓慢变化时总谐波畸变率为0.13%。仿真结果表明:当系统参数和负荷有较大变化时系统能很好的跟踪参考电压,控制策略是可行的。

A dual-loop controller design for three-phase voltage inverters was developed in the αβ reference frame to achieve fast transient response and good steady-state accuracy. The controller has an inner inductance current loop and an outer voltage loop, with the voltage loop design based on discrete integral sliding mode control to improve the steady-state accuracy and the robustness. When tracking a sine wave reference voltage, the settling time is 2 ms and the total harmonic distortion is 3.46% with an applied abruptly resistive load. The total harmonic distortion is 0. 13% with the system parameters varying gradually. Simulations show that the controller accurately tracks the reference in the presence of load disturbances and parameter variations.