Abstract A traditional control strategy for DC-DC converters of cascaded power electronic transformer is double closed-loop control based on real-time power feedback. One of its advantages is that the strategy brings out the power reference and makes it possible to achieve more functions through regulating the transmission power. On this basis, a novel DC voltage balance control strategy is proposed in this paper. DC voltage deviation of the input cell is added onto the power reference of relevant cell, and power allocation can be adjusted to better realize DC voltage balance automatically. Finally, simulation and experimental results verify the proposed feedforward control strategy.
Li Xiang,Hao Ruixiang,You Xiaojie等. A DC Voltage Balance Control Strategy for the Cascaded Power Electronic Transformer[J]. Transactions of China Electrotechnical Society, 2017, 32(2): 238-245.
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