Power grid wide-area relay protection method based on tide transient component predication

Abstract

The invention discloses a power grid wide-area relay protection method based on tide transient component predication. The method comprises the steps that the voltage phasors and the current phasors of all transformer substations of a power grid are synchronously measured through an existing wide-area measurement system of the power grid to acquire synchronous data of the power grid; if a trip fault happens on a single line of the power grid, a wide-area backup protection calculates an incidence matrix between currents of all lines of the power grid, calculates an incidence matrix between the currents of all the lines of the power grid and node injection currents and calculates the transient current variation of the other lines of the power grid after breakers at the two ends of the single line trip off, and then the line transient current variation obtained through calculation and the line transient current variation measured by the wide-area measurement system form relay protection criteria. According to the method, the calculation time is short, the speed of the protection action is high, the lines can be reliably locked before false operation of backup protection for line overload, the other faulty lines can be quickly isolated in a tripping mode, and therefore the operation security and stability of the power grid are improved.

Description

technical field [0001] The invention relates to the technical field of power system relay protection, in particular to a power grid wide-area relay protection method based on power flow transient component prediction. Background technique [0002] The task of relay protection is to reflect the fault and abnormal operation status of the protected components, which can be divided into main protection and backup protection according to their functions. Among them, the main protection is only responsible for the task of quickly removing the fault of the protected component, and is basically not affected by the operation mode of the system. With the application of Fibre Channel, the main protection technology of high-voltage and ultra-high-voltage systems based on double-ended electrical quantities has become increasingly mature. The backup protection is also responsible for the task of remote backup protection of adjacent electrical components. Due to the possibility of failure...

AI Technical Summary

Problems solved by technology

[0003] 1) The coordination relationship of backup protection is complex and the action time is long

In severe cases, it may not meet the limit cut-off time required by the stability of the power system, and then become a hidden danger to the safety of the large power grid

[0004] 2) It is very difficult to configure and set the backup protection, and it cannot track the changes in the operation mode of the power system, and even the protection mismatch or insufficient sensitivity may occur

[0005] 3) The backup protection cannot distinguish between the internal fault and the power flow transfer caused by the fault removal, which may lead to chain tripping of the backup protection under heavy load conditions

[0006] In a blackout accident, although the backup protection of the power system operates correctly according to the design principles, it objectively accelerates the system collapse.

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