Distribution Network Reconfiguration and Photovoltaic Optimal Allocation Considering Harmonic Interaction Between Photovoltaic and Distribution Network

Based on the analysis of the interaction mechanism between the photovoltaic grid-connected inverter and the background harmonic of the distribution network, an optimal planning strategy for changing the equivalent impedance of the common connection point from the grid side of the inverter to suppress the harmonic amplification of the grid-side harmonic voltage near the resonant frequency point is proposed. The optimization strategy is based on the static distribution network reconfiguration and photovoltaic configuration as the main means to optimize the equivalent impedance of the photovoltaic grid-connected point. At the same time, the active network loss and voltage deviation of the distribution network are optimized, and the mean value of harmonic voltage distortion rate, network loss and voltage deviation of harmonic monitoring points are taken as the objective function. At the same time, the harmonic monitoring points are optimized by the Pearson correlation coefficient, and the harmonic level of the whole distribution system is reflected by the harmonic monitoring points. Taking IEEE-33 and IEEE-69 bus distribution systems as examples for comparative analysis, the NSGAII algorithm is used to solve the problem. The results show that the joint optimization of distribution network reconfiguration and photovoltaic configuration can effectively suppress the interaction between photovoltaic injection harmonics and background harmonics of the distribution network. It effectively reduces the active power loss of the whole distribution network and the voltage deviation of the distribution network bus, and improves the minimum voltage of the distribution network. The effectiveness of the proposed PV optimal configuration strategy is verified by comparing the examples of different distribution systems.