考虑交直流多谐波耦合的模块化多电平换流器矩阵建模

谐波耦合矩阵模型可为电力系统线路和元件的谐波稳定性研究提供有效支撑。但对于内部结构复杂的模块化多电平换流器(MMC),已有研究中的矩阵模型不能描述其交、直流侧谐波间耦合关系或只能对特定次数谐波的耦合关系进行讨论。故考虑MMC开关函数可描述换流器的特定次数谐波间耦合关系，但其本身为周期时变的特点，以及谐波状态空间理论(HSS)可以将周期时变模型定常化，同时描述各量全部次数谐波间耦合关系的优点，将两者结合以搭建了可同时描述MMC交、直流侧各电气量的全部次数谐波间关系的谐波耦合矩阵模型。将加入谐波扰动后的MMC谐波耦合矩阵模型的理论计算结果与PSCAD电磁仿真模型仿真结果对比，证明了该模型对MMC谐波耦合特性描述的准确性。

Matrix modeling of modular multilevel converter considering multi harmonic coupling of AC and DC

The harmonic coupling matrix model can provide effective support for the study of harmonic stability of power system lines and components. However, for the modular multilevel converter (MMC) with complex internal structure, the matrix model in the existing research can not describe the coupling relationship between harmonics or only discuss the coupling relationship of specific harmonics. Therefore, considering MMC switch function can describe the coupling relationship between specific harmonics of converter, but it is periodic time-varying in itself, and the advantage that HSS can stabilize the periodic time-varying model and describe the coupling relationship between all times of har-monics of various quantities at the same time, the combination of the two can build all times of harmonics that can describe all electric quantities of AC and DC sides of MMC at the same time Harmonic coupling matrix model of wave coupling relationship. Finally, the theoretical calculation results of MMC harmonic coupling matrix model with harmonic disturbance are compared with the simulation results of PSCAD electromagnetic simulation model, which proves the accuracy of the model in describing MMC harmonic coupling characteristics.