Distributed PV Access Modes and Fault Handling Strategies in Electric Power Distribution Networks

To solve the access problem of distributed power generation, combined with the prediction and analysis of the reverse overload of distribution transformers, the customer voltage deviation exceeding the allowable limit, and the power imbalance and energy imbalance in the area, the access modes of distributed power generation are divided into four categories: free access mode, self-use external supply mode, supporting energy storage mode, and wide-area consumption mode. The planning principles of the four categories of modes are pointed out, and solutions to the problems of reverse overload of distribution transformers, user voltage deviation exceeding the allowable limit, power imbalance, and energy imbalance in the station area are proposed. A measure is proposed to detect low voltage and wait for relay protection action before deciding whether to disconnect from the grid, which can effectively reduce the number of distributed power sources disconnected from the grid due to faults.