Abstract:Inverter is one of the key components in the photovoltaic grid-connected power generation systems. In this paper, a new duty cycle control strategy for PV grid-connected inverter was proposed and implemented in DSP-based system, and the duty control equation is also deduced to realize the grid connection with unit power factor by adjusting the duty based on the state average principle. The new control strategy has the following advantages: this strategy can effectively prevent the affects on grid current for fluctuations of PV cells output voltage because the DC voltage output of photovoltaic cells is included in the calculation of duty cycle, in addition, has no PI controller compared with the conventional control strategy for grid-connected inverter, which results in simple control structure , fast dynamic response and low cost. Finally, some simulated and experimental results are given to illustrate the performance of the proposed strategy.
胡雪峰, 龚春英. 光伏并网逆变器的直接预测控制策略及其DSP实现[J]. 电工技术学报, 2011, 26(1增): 103-107.
Hu Xuefeng, Gong Chunying. A New Predictive Control Strategy for Photovoltaic Grid Connected Inverter and Its DSP Implementation. Transactions of China Electrotechnical Society, 2011, 26(1增): 103-107.
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