Abstract：A synchronous control method based on power balance is proposed to solve the problem that the input current THD of power factor correction can be greatly affected by phase unbalance, harmonics, offset, notching and so on. Furthermore, the feedforward control of load current is added to restrain the disturbance of both grid voltage and load, which improves the dynamic performance of system. On the basis of analyzing the mathematical model of three-phase three-level rectifier, a digital compensator for neutral point potential control is designed to suppress voltage unbalance of the capacitors. Simultaneously the amplitude regulation of the compensator is optimized using particle swarm optimization algorithm, which reduces the effect of neutral point potential adjustment on current THD. The control method is verified by the experimens on a prototype of 2.4kW, of which the THD is less than 5% when fully loaded, and the deviation of neutral point potential is less than 5V.
张东升, 张东来, 王陶, 苏宝库. 三电平整流器的PFC及中点平衡控制方法[J]. 电工技术学报, 2009, 24(10): 81-86.
Zhang Dongsheng, Zhang Donglai, Wang Tao, Su Baoku. PFC and Neutral Point Balanced Control Method of Three-level Rectifier. Transactions of China Electrotechnical Society, 2009, 24(10): 81-86.
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2009, Vol. 24 
