Calculation of Line Loss in Low Voltage Line with PV Based on Analytical Model

The rapid development of distributed photovoltaic (PV) is conducive to energy conservation and emission reduction, but its large-scale access also have influence on the low-voltage distribution network line loss. In this paper, a calculation method of low voltage line loss is proposed based on the power flow calculation method of backward-forward substitution. The analytical model of line loss calculation under uniform power network is established, and the relationship between the PV output and the change of line loss is given. An example model of a 15-node low-voltage distribution network with PV is built, and the correctness of the proposed method is verified with the comparison of the analytical model and the simulation model. The influence of three-phase unbalance, PV access capacity and access position on system line loss is analyzed, which provides theoretical basis and decision support for distributed PV access, low-voltage distribution network loss reduction and energy saving.