The structure of the high-voltage test transformer is made of cold-rolled silicon steel sheets stacked together. The coil is a concentric pagoda shaped multi-layer cylindrical structure, with the low-voltage coil inside and the high-voltage coil outside; The shell is portable, with advantages such as small size, light weight, beautiful appearance, and easy mobility.Reasons and solutions for the generation of floating potential in high-voltage test transformers:
Reason: The clamping channel steel, pressure nail bolts, pull plates and other components of the transformer have been sprayed with blue paint, and the contact between each component is not very good. Under the action of the leakage magnetic field, the floating potential discharge between each component produces a sound.
Judgment method: The floating potential discharge makes a very slight "squeaking, squeaking" sound, which can only be heard by listening carefully. Users often mistake it for the high or low voltage of the transformer discharging.
resolvent:
1) This discharge will not affect the normal operation of the transformer.
2) During power outage maintenance, the paint on areas with poor contact can be scraped off to ensure good contact between the various components of the transformer.
Reason: Distortion of the voltage waveform of the transformer (such as resonance phenomenon), resulting in noise.
Judgment method:
1) In addition to the noise from the transformer itself, there is also a "clucking, clucking" noise mixed in.
2) During operation, there will be a sudden increase in transformer noise.
Reason: High voltage can cause overexcitation of the test transformer, resulting in increased and sharp noise, which directly and seriously affects the noise of the test transformer
Judgment method: First, check the low voltage output voltage. Do not look at the voltmeter on the low voltage cabinet, which only serves as an indicator. A more accurate multimeter should be used for measurement
Solution: Currently, the 10KV voltage in cities is generally high. Based on the output voltage on the low voltage side, the tap changer should be placed in the appropriate position On the premise of ensuring the quality of low-voltage power supply, try to increase the high-voltage tap (reduce the low-voltage output voltage) as much as possible to eliminate the overexcitation phenomenon of the test transformer and reduce the noise of the test transformer.