Control method of multi-point grounding current of transformer fixture under double current transformer monitoring

Abstract

The invention discloses a control method for multi-point grounding current of transformer clips under monitoring by double current transformers, and solves the problem of affecting the normal operation of the power grid caused by the prior art operation mode of power failure and current limiting of the grounding current of transformer clips. The grounding lead wire (9) of the clip is connected to the input end (21) of the switching circuit after passing through the coil of the first current transformer (10), and the two ends of the secondary side induction coils of the two current transformers are respectively connected to AD The two input interfaces of the conversion interface circuit are connected, the output end of the AD conversion interface circuit (15) is connected to the single-chip microcomputer (17), and the output end (22) of the switching circuit is connected to the ground end (6). The impedance unit of each switching branch adopts triac to control the on-off of the branch. By controlling the conduction angle, the on and off of the impedance branch can be controlled to realize the switching of the impedance unit. The invention has strong operability and ensures the normal and safe operation of the power grid.

Description

technical field [0001] The invention relates to a method for controlling the grounding current of substation equipment, in particular to a method for monitoring and regulating the grounding current of a clip in a transformer. Background technique [0002] When the transformer is running, an uneven electric field will be formed between the transformer winding and the lead wire and the oil tank, and metal components such as the transformer core and its clamps are all in the electric field. The transformer clamp will generate a floating potential through the coupling effect of the capacitor. When the potential difference between the floating potential on the clamp and other parts in the transformer reaches a certain value, the insulation between them will be broken down and spark discharge will occur. Burn out the transformer. Therefore, the transformer clamp must be effectively grounded, and multi-point grounding of the transformer clamp should also be avoided. When the tran...

AI Technical Summary

Problems solved by technology

[0003] The invention provides a method for controlling the multi-point grounding current of transformer clamps under the monitoring of double current transformers, and solves the technical problem of affecting the reliable operation of the power grid caused by the operation mode of power failure and current limiting for the grounding current of transformer clamps in the prior art

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