On-line monitoring system of transformer winding

Abstract

The invention provides an on-line monitoring system of a transformer winding. The on-line monitoring system of the transformer winding is used for accomplishing 24-way voltage and current signal conditioning, data acquisition, signal processing, reactance calculation and communication with a backstage control cabinet of the transformer winding based on a computer real-time data acquisition system. The 24-way voltage and current signal conditioning comprises 12-way voltage connection and conditioning and 12-way current connection and conditioning. Three American national instrument data acquisition cards PCI 6220 are used for synchronously collecting all signals in data acquisition. The on-line monitoring system of the transformer winding has the advantages of being capable of monitoring deformation of a winding by calculating short-circuit reactance of the winding of a main transformer of the converting station on line and in real time, providing important reference for maintenance of the converting station, applicable to field application, and being capable of being actually used in long-term operation, capable of providing rich monitoring functions which comprise input and output of effective values of voltage and current, wave form data, tendency charts of the reactance and the like, capable of providing flexible inquiry statistics based on designs of databases, and capable of enabling a user to review historical operation through rich and various data display forms.

Description

technical field [0001] The invention relates to an online monitoring system of a transformer winding. Background technique [0002] Transformer winding deformation refers to changes in the axial and radial dimensions, body displacement, inter-turn short circuit, winding twist, and bulging after the winding is stressed. The main causes of transformer winding deformation are: [0003] 1) It is unavoidable for the transformer to be impacted by various short-circuit faults during operation, including three-phase short-circuit, two-phase short-circuit and relative ground fault, etc., especially the short-circuit at the exit or near the transformer is the most harmful, and the huge short-circuit The inrush current causes the transformer winding to receive a large electromotive force, and causes the winding to heat up sharply. At a higher temperature, the mechanical strength of the wire becomes smaller, and the electromotive force is more likely to damage the winding. [0004] 2)...

AI Technical Summary

Problems solved by technology

[0003] 1) It is unavoidable for the transformer to be impacted by various short-circuit faults during operation, including three-phase short-circuit, two-phase short-circuit and relative ground fault, etc., especially the short-circuit at the exit or near the transformer is the most harmful, and the huge short-circuit The impact current makes the transformer winding receive a lot of electromotive force, and causes the winding to heat up sharply. At a higher temperature, the mechanical strength of the wire becomes smaller, and the electromotive force is more likely to damage the winding.

[0004] 2) Accidental collision and vibration of the transformer during transportation or installation will cause deformation of the transformer winding

[0005] 3) There is a dead zone or action failure in the transformer protection system, which leads to short-circuit current for too long, which may cause winding deformation

[0008] 1), the insulation distance changes, or the solid insulation is damaged, which will lead to partial discharge

When encountering overvoltage, the insulation damage of the winding may occur, resulting in partial discharge. If the partial discharge acts for a long time, the insulation damage will gradually expand, and eventually lead to insulation breakdown accidents in the transformer.

[0009] 2) Accidental collision and vibration of the transformer during transportation or installation will cause deformation of the transformer winding

The mechanical performance of the winding is degraded. When it is subjected to the short-circuit current impact again, it will not be able to withstand the huge impact electromotive force and damage accidents will occur.

[0010] 3) Operating experience shows that once the winding deformation of the operating transformer occurs, it will lead to a cumulative effect

[0022] The existing or under-developed online transformer winding monitoring system is usually based on an embedded system, which is limited by the speed of the processor, the signal processing capability is weak, and the implementation of related improved algorithms is relatively complicated, and the cost of subsequent on-site continuous improvement is relatively high

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