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Causes and treatment of floating potential

time:2020/12/1   source:华天电力  reading:292 time

Important causes and treatment and management methods of high-voltage test transformer suspension potential

Reason: The channel steel of the transformer clamp, the pressure nail bolt, and the pull plate are sprayed with blue paint, and the contact between the parts is not very good. There is a floating potential discharge sound between the high-voltage test transformer under the action of the leakage magnetic field.

Judgment and analysis method: The discharge of the floating potential makes a very slight "squeak, squeak" sound, which can be heard by listening carefully. Users often mistakenly believe that a transformer is discharging at high voltage or low voltage.

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1) This discharge will not have a serious impact on the normal working environment of the transformer.

2) The paint that touches some bad places can be scraped off when the power is off for maintenance. Let the transformer parts companies have a good contact.

Reason: The voltage signal waveform of the transformer can be distorted (such as resonance phenomenon), which will affect noise.

Judgment method:

1) In addition to the noise of the high-voltage test transformer itself, the noise is also mixed with "guckling" noise.

2) During the operation and management process, a transformer noise environment will suddenly become louder.

Reason: The high voltage will cause us to test and study the transformer overexcitation, and the noise will increase and sharp, which will directly lead to the noise of the test transformer which is a serious social factor.

Judgment and analysis method: first look at the low-voltage output working voltage, not the voltmeter on the low-voltage cabinet. The voltmeter is only an indicator. It should be possible to use a more comprehensive and accurate multimeter for data measurement.

Solution: The current 10KV voltage in cities is generally high. According to the output voltage of the low-voltage side, the tap should be placed in the appropriate gear. Under the premise of ensuring the quality of low-voltage power supply, the high-voltage tap should be adjusted upwards as far as possible (the low-voltage output working voltage can be lowered), so as to eliminate the test and research transformer. Excitation phenomenon. At the same time by reducing the noise of the engineering test transformer.

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