A method and device for inter-turn protection of a pumped reactor

Abstract

The invention discloses an energy extraction electric reactor interturn protection method and an energy extraction electric reactor interturn protection device. The energy extraction electric reactor interturn protection method comprises the steps of: adopting an output end negative sequence voltage of an energy extraction winding side of an energy extraction electric reactor and an output end negative sequence current of the energy extraction winding side of the energy extraction electric reactor for calculation, so as to obtain a negative sequence impedance measured value Z<2.cn>; comparing the negative sequence impedance measured value Z<2.cn> with a negative sequence setting impedance value Z<2.set> of the energy extraction winding side, judging whether to block energy extraction electric reactor interturn protection or not, and determining that a position where a fault occurs is not outside a region of the energy extraction winding side of the energy extraction electric reactor when the Z<2.cn> is greater than the Z<2.set>; and determining that the position where the fault occurs is outside the region of the energy extraction winding side of the energy extraction electric reactor when the Z<2.cn> is less than the Z<2.set>, and blocking the interturn protection. The energy extraction electric reactor interturn protection method and the energy extraction electric reactor interturn protection device are used for monitoring unsymmetrical faults of the energy extraction electric reactor in real time, can distinguish faults inside and outside the region of the energy extraction winding side of the energy extraction electric reactor rapidly and accurately, and are capable of reliably braking faults outside the region of the energy extraction winding side without reducing normal interturn protection flexibility.

Description

technical field [0001] The invention relates to the field of power system protection, in particular to an inter-turn protection method and device for a pumping reactor based on negative-sequence impedance blocking at the pumping side. Background technique [0002] Pumping reactors are quite different from traditional reactors and transformers. Because the pumping windings are usually located on side yokes, the coupling between the primary and secondary sides is weak, and the rated capacity of the main reactor side and the rated capacity of the pumping winding side are hundreds of times different. Current longitudinal differential cannot be installed. [0003] The traditional turn-to-turn protection based on negative sequence power direction, zero-sequence power direction turn-to-turn protection and zero-sequence power direction turn-to-turn protection with compensation voltage use traditional shunt reactors, and do not consider pumping reactors and traditional reactors. dif...

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Problems solved by technology

[0005] The purpose of the present invention is to provide a pumping reactor turn-to-turn protection method and device based on the negative-sequence impedance blocking of the pumping side, which is used to solve the problem of failure of the pumping reactor turn-to-turn protection outside the side area of ​​the pumping winding. The method is to calculate the negative sequence impedance obtained by calculating the three-phase voltage and three-phase current of the energy-pumping winding side of the energy pumping reactor, and compare it with the set impedance criterion to improve the sensitivity of the original turn-to-turn protection without reducing the sensitivity. The reliability of the protection action

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