低惯量直流微电网并网变换器的预测电流分区补偿控制策略

低惯性直流微电网在负荷频繁投切、新能源出力波动等情况下易发生直流母线电容两侧功率不匹配的问题.通过分析直流微电网接口并网变换器输入、输出侧功率失衡机理,依据母线电压变化水平计算母线电压恢复至指令值所需能量和单位采样周期内母线电容能量变化信息,得到线性处理后的母线电容瞬时输出功率、母线电压波动等效负荷信息,最终确定电流指...

Predictive current partition compensation control strategy for low inertia DC microgrid interfaced grid-connected converter

Under the condition of frequent load switching and new energy output fluctuation, low inertia DC microgrid is prone to the problem of power mismatch on both sides of DC bus capacitor. The input and output power imbalance mechanism of grid-connected converter with DC microgrid interface is analyzed. According to the bus voltage change level, the energy required for bus voltage to recover to the command value and the bus capacitor energy change information in unit sampling period are calculated. The instantaneous output power of bus capacitor and the equivalent load information of bus voltage fluctuation after linear processing are obtained, and then the full value of current command compensation is determined. Considering the influence of voltage outer loop, a fast partition compensation strategy of current command is proposed. The smooth transition of partition is realized by adjusting the coefficient, and the fast tracking of current command is realized by model predictive current control, which improves the compensation res-ponse speed of grid-connected converter and suppresses bus voltage fluctuation. Finally, the effectiveness and feasibility of the proposed control strategy are verified by simulation and experiment.