Distributed power supply-containing petal-type urban power grid regional backup protection method

A technology of distributed power supply and urban power grid, which is applied in the field of protection and control of power system distribution network, and can solve problems such as changing system operation modes, difficult to remove faults, and reduced sensitivity of relay protection

CN112595930AActive Publication Date: 2021-04-02STATE GRID HEBEI ELECTRIC POWER CO LTD +2
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Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2021-04-02

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Abstract

The invention provides a distributed power supply-containing petal-type urban power grid regional backup protection method, and the method comprises the steps: enabling two ends of each line on a petal-type urban power grid trunk line to be provided with a protection device and a circuit breaker, and enabling each petal-type looped network trunk line to be provided with an even number of protection devices; setting each petal of the petal type urban power grid as an area, and setting an information processing center at each transformer substation; when a three-phase earth fault occurs on a trunk line of a petal type urban power grid containing a plurality of distributed power supplies, determining a fault section or a fault line step by step according to a comparison result of amplitudes of currents flowing through protections on two sides of a grid-connected point of the distributed power supplies; in the prior art, secondary equipment current transformers in a petal type urban powergrid are broken, so that the current at the current transformers cannot be obtained, maloperation or refusal of a protection device is possibly caused, heavy losses are further caused, and different countermeasures should be taken for the broken current transformers at different positions according to the situation.
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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 method for regional backup protection of the petal-type urban power grid with distributed power sources based on multi-source information is proposed. Background technique

[0002] With the rapid increase of load density, the traditional radial power grid has a large range of faults, and it is difficult to meet the development needs of high power supply reliability in urban power grids. Urban power grids gradually adopt single-loop and double-loop networks with "closed-loop design and open-loop operation" Wait for the wiring method. In addition, the petal-type wiring and operation mode have 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 ne...

Examples

Embodiment Construction

[0042] A kind of backup protection method based on multi-source information of the present invention contains distributed power petal type urban power grid area, comprises the following several aspects:

[0043] (1) Protection devices and circuit breakers are installed at both ends of each section of the main line of the petal-shaped urban power grid, so each main line of the petal ring network is equipped with an even number of protection devices. In the clockwise direction, number each protection device in descending order, starting from 1. For two adjacent lines, the line where the protective device with a smaller number is defined as the upstream line, and the line where the protective device with a larger number is defined as the downstream line, so the protection at the upstream side of the line is called an odd-numbered protection, and the line at the downstream side of the line is defined as an odd-numbered protection. The protection is even protection. Each petal of ...