Countermeasures for Distributed Photovoltaic Grid Integration Problems and Exploration of Relay Protection Methods

Photovoltaic power generation technology is progressing and developing in modern society. It also causes some problems in keeping the electrical grid safe to operate. In this paper, the impact of distributed photovoltaic power generation on the low-voltage power grid during the grid connection is analyzed, and related countermeasures for relay protection are proposed. This paper examines the effects of electricity quality on the power grid and suggests prioritizing access to low-voltage energy to prevent negative consequences. Distributed photovoltaic power generation systems after being grid-connected may appear to be the phenomenon of the islanding effect. In addition to the aforementioned issues, connecting large-scale distributed PV to the power grid can significantly impact its operation, hence requiring that the PV power generation system's relay protection configuration conform to the power grid standards. Low-voltage grid connection does not mean complete safety; high-frequency modulation of inverters may cause harmonic problems, and unstable generating capacity during cloudy and rainy weather can affect grid operation and electricity quality. The paper analyzes the causes of electricity quality and islanding effect and proposes countermeasures for the corresponding problems. In terms of relay protection, the article proposes solutions including the addition of protective components and enhanced information exchange between the grid and distributed PV. The research findings enhance distributed PV power generation system's reliability and grid operation stability by offering valuable guidance and reference for future research and practice.