Abstract：The multiple parallel-connected inverter technique can improve the power capacity of the motor-drive system effectively. However, the above technology causes some problems, such as the circulating current, the unbalanced current, and so on. To solve these problems, the mathematic model of multiple parallel-connected inverters is constructed, the concept of the unbalanced current degree is presented, and the expression of the circulating current and the unbalanced current degree are also given. Moreover, the reason for the circulating current and the unbalanced current is analyzed. It can be seen that the circulating current is caused by the different output voltages of the parallel inverters. Based on the above analysis, the master-slave controller hardware circuit block is proposed to suppress the circulating current and the unbalanced current. The question is solved by the pulse delay compensation method. The experimental results verify the correction of the proposed method.
张建文, 王鹏, 王晗, 蔡旭. 多逆变器并联的均流控制策略[J]. 电工技术学报, 2015, 30(18): 61-68.
Zhang Jianwen, Wang Peng, Wang Han, Cai Xu. Average-Current Control Strategy of Multiple Parallel Inverters. Transactions of China Electrotechnical Society, 2015, 30(18): 61-68.
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