Distributed generation fast-disconnecting system and method

Abstract

The invention discloses a distributed generation fast-disconnecting system. The distributed generation fast-disconnecting system is characterized in that the system comprises a backup automatic switching device, feeder protection devices, a communication network, distributed generation (DG) measure preserving devices and information encryption devices. The backup automatic switching device, the feeder protection devices and the DG measure preserving devices are connected through the communication network; the backup automatic switching device and the feeder protection devices are located in substations; the DG measure preserving devices are located in distributed substations; the backup automatic switching device sends encrypted GOOSE disconnecting signals to all the DG measure preserving devices connected with feeders of the substations, and the feeder protection devices send the encrypted GOOSE disconnecting signals to all DGs, connected with the feeder protection devices, of the feeders; the DG measure preserving devices receive the GOOSE disconnecting signals sent by the backup automatic switching device and the feeder protection devices and judge whether to perform tripping operation for disconnection after the GOOSE disconnecting signals are decrypted.

Description

technical field [0001] The present invention relates to the technical field of distributed power generation, and more specifically, to a system and method for fast decoupling of distributed power sources. Background technique [0002] Distributed Generation (DG, Distributed Generation) refers to a power generation system that uses distributed resources, has a small installed capacity, is arranged near users, and is connected to the distribution network. According to the energy type of power generation, distributed power generation mainly includes: wind power generation, solar power (photovoltaic cells, photothermal power generation), biomass power generation, internal combustion engines fueled by liquid or gas, micro gas turbines, ocean power generation, fuel cells, etc. Distributed power generation has gradually become an important form of power generation because of its low investment cost, small footprint, clean and environmentally friendly, and in line with my country's ...

AI Technical Summary

Problems solved by technology

[0004] 1) The unloading speed is slow, and the frequency and voltage protection voltage needs the grid frequency and voltage value to drop below the low frequency and low voltage setting or rise above the overfrequency and overvoltage setting to act, and the response is slow

[0005] 2) The sensitivity is poor. Before the reclosing and backup auto-switching actions, the DG runs in an island state. The frequency and voltage deviation in the island depend on the power difference in the island. The smaller the power difference, the frequency and voltage deviation The smaller it is, the frequency and voltage protection may refuse to operate

[0006] 3) Poor reliability, frequency and voltage protection are easily affected by short-circuit faults of adjacent lines, PT disconnection, voltage fluctuations and other working conditions, and are prone to malfunction

Images