Abstract：The power quality, including total harmonic distortion(THD) and direct current injection(DCI), restricts the massive application of photovoltaic grid-connected generation system. Novel methods focusing on DCI suppression and THD reduction are proposed to improve the quality of output current. DC current extraction circuit is designed and control strategy based on prediction algorithm is used to eliminate the DC offset current. Multi-vector proportional integral(MVPI) current controller based on VPI is adopted to decrease the THD. Also, the relationship between DCI and THD is discussed, which implies that both of them are closely connected, and optimization of one can enhance the other obviously. Experiments on 20kW PV inverter prototype have shown the effectiveness and practicality of the proposed method.
张国月,秦梦珠,齐冬莲,吴越,张建良. 三相光伏并网发电系统THD及DCI优化方法研究[J]. 电工技术学报, 2015, 30(16): 238-245.
Zhang Guoyue,Qin Mengzhu,Qi Donglian,Wu Yue,Zhang Jianliang. Research on Optimization Method of THD and DCI in Three-Phase Grid-Connected PV Generation System. Transactions of China Electrotechnical Society, 2015, 30(16): 238-245.
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