Alternating-current test device for bare switch operating characteristics of transformer on-load tap-changer

Abstract

The invention relates to an alternating-current test device for bare switch operating characteristics of a transformer on-load tap-changer, and belongs to the technical field of transformer switches. The invention aims to provide a transformer on-load tap-changer bare switch operating characteristic alternating-current test device which carries out an operating characteristic alternating-current test in allusion to a bare switch of an on-load tap-changer. The test device provided by the invention is characterized in that the 220V alternating-current mains supply is connected through an interface P1 at first and then transmitted to a transformer T1 and an AC-DC conversion chip respectively through a switch S1, pins 5, 6, pins 3, 4 and pins 1, 2 of an interface IN are externally connected with the output ends of a phase A, a phase B and a phase C of the bare switch of the on-load tap-changer in series respectively, and an output interface of an operating circuit of each phase of the bare switch is equipped with a resistor R; and the pins 5, 6, the pins 3, 4 and the pins 1, 2 are internally connected to pins 1, 2 of the input ends of current sensors S, S2, S3 respectively, and the current sensors S1, S2, S3 respectively correspond to the phase A, the phase B and the phase C of the bare switch of the on-load tap-changer respectively. The alternating-current test device discovers and judges problems such as insufficient contact pressure of a switch contact and the like in allusion to the bare switch of the on-load tap-changer without a transformer winding, the test effect and the test efficiency are improved, and a burning accident of power grid main equipment is effectively prevented.

Description

technical field [0001] The invention belongs to the technical field of transformer switches. Background technique [0002] As one of the main equipments in the power system, the power transformer's working state is related to the operation safety of the entire power system. In the late 1980s, my country began to use on-load voltage regulating transformers in the power grid to realize variable ratio power supply of transformers and provide users with power resources with qualified voltage quality. At present, on-load voltage regulating transformers in the national power supply network account for more than 90% of the total number of transformers. Transformer accidents caused by transformer on-load tap-changers have also skyrocketed, which directly leads to transformer burnout and affects the reliability of power supply. Therefore, the detection of the action characteristics of the transformer on-load tap-changer has become one of the important contents to determine the stabi...

AI Technical Summary

Problems solved by technology

It is mainly a tap changer with a transformer winding. Because of the existence of the winding, there will be a large impedance in the circuit under the condition of alternating current, so a large three-phase alternating voltage value must be added during the test. The requirements for the power supply Even higher, but even if the measured current value is only milliampere level, it is relatively difficult in terms of acquisition and processing accuracy

[0004] For other AC test devices, on the one hand, the test equipment is bulky, the integration level is not high, and the test accuracy is poor; on the other hand, the test process is more man-made, the degree of automation is small, and the operation process is complicated.

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