Abstract In this paper, the charge modes of Modular Multilevel Converter (MMC) in High Voltage Direct Current Transmission System (HVDC) are studied. The charge mode is by dc grid when MMC is connected to the passive network. The over charge must be exist according to the mathematical model of MMC. In order to suppress overvoltage, a new charging strategy by dc grid at controllable situation is proposed. And the calculation formulas of the charging coefficients are given by the limits of MMC. Meanwhile, the change trend of charging current is researched and the maximum value is computed by mathematical model of MMC. Experiment results on a HVDC based on MMC show validity of the proposed method.
Chu Zunfang,Li Yaohua,Wang Ping等. Analysis of Charging Strategy by DC Grid of Modular Multilevel Converter in High Voltage Direct Current Transmission System[J]. Transactions of China Electrotechnical Society, 2015, 30(12): 136-142.
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2015, Vol. 30 
