Regional backup protection method of petal-type urban power grid with distributed power

Abstract

The invention provides a regional backup protection method for a petal-type urban power grid with distributed power sources, comprising: protection devices and circuit breakers are installed at both ends of each line on the main line of the petal-type urban power grid, and Equipped with an even number of protection devices; each petal of the petal-type urban power grid is set as an area, and an information processing center is set at each substation; In the event of a phase-to-ground fault, the fault section or fault line is gradually determined according to the comparison results of the amplitudes of the current flowing through the protection on both sides of the grid-connected point of the distributed power supply; the current transformer of the secondary equipment in the petal-type urban power grid will be disconnected, which will lead to the current at the place. If it cannot be obtained, it may cause the protection device to malfunction or refuse to operate and cause heavy losses. In response to this situation, different countermeasures should be taken for the disconnection of current transformers at different positions.

Description

technical field [0001] The invention belongs to the field of protection and control of power system distribution network. Based on the analysis results of the fault characteristics of the petal-type urban power grid, a multi-source information-based regional backup protection method for the petal-type urban power grid with distributed power sources is proposed. Background technique [0002] With the rapid growth of load density, the traditional radiation-type power grid has a large fault influence range, and it is difficult to meet the development needs of high power supply reliability of urban power grids. and other wiring methods. In addition, the petal-type wiring and operation method has attracted widespread attention because of its high reliability, and more and more areas with high load density and high power supply reliability have begun to adopt this new type of connection and operation method. On the other hand, with the high proportion of distributed power access,...

AI Technical Summary

Problems solved by technology

On the other hand, with the high proportion of distributed power access, the complexity of the urban power grid topology increases, the system operation mode is changeable, and the direction of the power flow is uncertain, which makes the urban power grid present new fault characteristics, resulting in the traditional local-based A large amount of relay protection sensitivity is reduced or even lost selectivity, it is difficult to remove the fault with correct action

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