Flexible Model Predictive Control with Peak Current Limitation for Grid-Connected Inverter under Unbalanced Grid Voltage
Jin Tao1, Shen Xueyu1, Su Taixin1, Guo Jingdong2
1. Fujian Key Laboratory of New Energy Generation and Power Conversion Fuzhou University Fuzhou 350116 China; 2. State Grid Fujian Electric Power Research Institute Fuzhou 350007 China
Abstract：In order to overcome the problem of power fluctuation and over-current in grid-connected inverters under unbalanced grid voltage, a flexible unbalanced control strategy based on model predictive control with peak current limitation for grid-connected inverters is proposed. This method is aimed at balancing the current, eliminating active and reactive power oscillations to design a current reference generator. The quantitative relationship between the power reference set value and the peak output current value is obtained through the power reference generator to guide the power reference setting under unbalanced grid voltage. On this basis, the control strategy of grid-connected model predictive current based on reference voltage to establish cost function method is given, and the reference current is accurately tracked. Simulation and experimental results show that the proposed method can flexibly realize the control of output current balance, active or reactive power constant under unbalanced grid voltage, and the current peak is limited effectively under the balance current, constant active and reactive power mode.
金涛, 沈学宇, 苏泰新, 郭敬东. 不平衡电网下并网逆变器的模型预测电流限幅灵活控制[J]. 电工技术学报, 2019, 34(11): 2342-2353.
Jin Tao, Shen Xueyu, Su Taixin, Guo Jingdong. Flexible Model Predictive Control with Peak Current Limitation for Grid-Connected Inverter under Unbalanced Grid Voltage. Transactions of China Electrotechnical Society, 2019, 34(11): 2342-2353.
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2019, Vol. 34 
