KE Shunchao, ZHU Miao, CHEN Yang, et al. Treatment Strategy of Unbalanced Grid Voltage Conditions Based on MMC-UPFC Passive Sliding-mode Variable Structure Control[J]. 2020, 46(3): 1078-1086.
KE Shunchao, ZHU Miao, CHEN Yang, et al. Treatment Strategy of Unbalanced Grid Voltage Conditions Based on MMC-UPFC Passive Sliding-mode Variable Structure Control[J]. 2020, 46(3): 1078-1086.DOI:
Three-phase unbalanced voltage condition is a common scenario in urban power grid. Modular multilevel converter based unified power flow controller(MMC-UPFC) plays an important role in smart grid active control. A passive sliding-mode control strategy of MMC-UPFC is proposed in this paper. Firstly
both positive-and negative-sequence passive controllers based on Euler-Lagrange(EL) model of MMC are established with a damping injection method according to the passive control theory. Since precise model parameters are required for a passive controller
sliding mode variable structure control is proposed. The control system has fast response and is not sensitive to parameter variation. The series converter of MMC-UPFC treats unbalanced grid voltage condition by compensating the negative sequence grid voltage. Finally
a simulation model of 27-level MMC-UPFC based on real project is constructed. The validity of proposed MMC-UPFC control strategy and its treatment of unbalanced grid voltage condition are verified by simulation results.