Auxiliary device for transformer winding condition monitoring

Abstract

The invention relates to a transformer winding state monitoring auxiliary apparatus which includes a first vibration sensor, a second vibration sensor, a third vibration sensor, a fourth vibration sensor, a current transformer, a data acquiring device and an industrial control computer. The first vibration sensor, the second vibration sensor and the third vibration sensor are separately arranged between three-phase high voltage winding binding posts and three-phase low voltage winding binding posts on the upper surface of a transformer case body. The fourth vibration sensor is arranged on a side surface of the transformer case body. The current transformer is arranged on a power supply electricity line approximate to a B-phase high voltage winding binding post. The first vibration sensor, the second vibration sensor, the third vibration sensor, the fourth vibration sensor and the current transformer are all connected to an input end of the data acquiring device. An output end of the data acquiring device is connected to an input end of the industrial control computer. The apparatus can monitor transient signals and state variations of the no-load switching-in of the transformer so as to serve to assist the loosening and deformation monitoring of the transformer winding.

Description

technical field [0001] The invention relates to a transformer winding state monitoring auxiliary device, which belongs to the technical field of power transformer safety monitoring. Background technique [0002] As the key equipment of power transmission, the reliability and stability of power transformer greatly affect the safe operation of the entire power grid. According to relevant data, more than 50% of transformer faults come from external short circuits, and the huge electromagnetic force generated by external short circuits will further cause major defects such as loosening and deformation of transformer windings. [0003] Due to external short-circuit impact, aging and other reasons, loose winding is a common defect in transformer use. The electromotive force generated by the current will cause the winding to vibrate, and the magnitude of the electromotive force is just like the square of the current. The existing technology generally uses the vibration signal chan...

AI Technical Summary

Problems solved by technology

When the transformer is closed with no load, it will generate a large excitation inrush current. In extremely serious cases, the amplitude of the excitation inrush current can reach hundreds of times the no-load current. Although the excitation inrush current exists for a short time, its value is very large. Big

[0005] The magnitude of the inrush current generated by no-load closing does not only depend on whether the winding of the transformer is loose. Angle and many other factors, it is not possible to unilaterally judge whether there is a fault in the transformer from the magnitude of the excitation inrush current

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