带LCL滤波器的电机控制复矢量解耦技术

Complex Vector Decoupling Technique for LCL Filtered Motor Control

采用复矢量对同步旋转坐标系(SRF)下的LCL型电机逆变器进行建模,深入研究不同控制策略下系统的整体相位裕度与耦合性能影响,揭示了逆变器不仅在dq轴间有耦合关系,主动阻尼反馈支路同样会加剧耦合现象。由此提出一种复矢量解耦策略,依次设计主动阻尼反馈支路和电流环系统的解耦环节,分别对反馈支路与PI控制器输出电流施加解耦环节,不仅可以有效消除动态耦合而且使系统具有良好的动态性能。通过仿真和试验与传统解耦控制效果作对比,验证了该控制策略的有效性。

The LCL motor inverter is modeled using the complex vector in the synchronous rotating reference frame(SRF),and the influence of the overall phase margin and coupling performance of the system under different control strategies is thoroughly investigated.The analysis reveals that the inverter has a coupling relationship between the dq axes,and the active damping feedback branch also intensifies the coupling phenomenon.To address these issues,a complex vector decoupling strategy is proposed.The decoupling components for the active damping feedback branch and the current loop system are sequentially designed.The decoupling elements are applied to both the feedback branch and the output current of the PI controller respectively,which not only effectively eliminate the dynamic coupling but also enhances the system's dynamic performance.Finally,the effectiveness of the control strategy is verified by comparing the simulation and experimental results with the traditional decoupling control.