Analysis of the Causes of User-Side Power Factor Deterioration in Distributed PV Power Generation Systems and Collaborative Control Solution

With the ongoing expansion of installed capacity in distributed photovoltaic (PV) power generation systems in China, the issue of power factor deterioration exceeding specified limits, caused by the connection of distributed PV systems to user-side grids, has become increasingly prominent. This paper analyzes the system architecture for connecting distributed PV power generation systems to user-side power grids, as well as the principles of grid power factor assessment. From multiple aspects, including the operation of reactive power sources within these PV systems and the operational mechanism of low-voltage reactive power compensation devices, the analysis focuses on the power factor issue at the division point of property for user-side grids. The paper proposes a collaborative control solution that integrates the selection of the optimal connection point location with the optimization of the inverter reactive power operation mode, along with a series of supplementary measures, including the replacement with four-quadrant reactive power controllers, the transformation of the secondary circuit for reactive power control, the addition of the upper-level reactive power compensation device. This comprehensive approach addresses the issue of out-of-limits at the division point of property in power factor assessments, providing a low-cost, innovative solution to the power factor issue associated with connecting distributed PV power plants to user-side grids