中文摘要：

模块化多电平高压直流输电系统（modular multilevel converter-high voltage direct current,MMC-HVDC）通常采用基于比例积分（proportional integral,PI）的双闭环矢量控制,而PI调节存在响应速度慢、dq电流需要旋转解耦等问题。为此文章提出在两相静止坐标下基于内模控制的MMCHVDC稳态控制方案。首先分析了两相静止坐标下的MMCHVDC数学模型,然后结合内模控制的特性,对电流内环的控制结构和参数进行设计,并将内模内环与PI外环结合构造出双闭环控制结构。最后在Matlab/Simulink中搭建了MMC-HVDC系统模型,对多种工况进行仿真。仿真结果表明,所设计的控制器能够有效抑制母线电压波动,并能对负荷变化快速响应,提高了系统的鲁棒性。

英文摘要：

Modular multilevel converter based HVDC（MMC-HVDC） transmission usually adopts double closed-loop vector control with PI, which has several problems such as slow response to disturbance and needs decoupling control under rotating coordinate. Therefore a new steady state control scheme of MMC-HVDC based on internal model controller is proposed under two-phase stationary coordinate. Firstly the mathematical model of MMC-HVDC system under two-phase stationary coordinate is introduced. By analyzing features of internal model control method, the control structure and parameters of the current cycle are designed,and a double closed-loop control system based on IMC inner-cycle and PI outer-cycle is built. The steady-state and dynamic performance of the proposed controllers under different operation conditions are shown with simulation of MMC-HVDC system in Matlab/Simulink. Simulation results show that the proposed controller really can suppress bus voltage fluctuations effectively, and respond quickly to load changes, greatly improving the robustness of the system.