Adaptive Backstepping Control Strategy for Y-type Modular Multilevel Converter Facing Fractional Frequency Transmission Systems
Targeting the problems of the low robustness and adaptability of Y-shaped modular multilevel converter(Y-MMC)under conventional proportion integral(PI)control strategy,the paper proposes a nonlinear adaptive backstepping control(ABC)strategy for Y-MMC.Firstly,a Y-MMC mathematical model is established according to the topology structure of Y-MMC.Then the design process of ABC strategy for Y-MMC is discussed in detail,and the stability of the system is proved.Finally,a Y-MMC simulation system is built on Simulink software platform for simulation verification.The proposed ABC strategy is compared with passivity-based control(PBC)and PI control strategies to verify the effectiveness and superiority of ABC strategy for Y-MMC under three different operating conditions.
fractional frequency transmission systemoffshore wind powerY-MMC converterABC Strategy