How to adjust transformer voltage

author: MagTop
How to adjust transformer voltage #power transformer#

The commonly used 10kv distribution transformer can adjust the voltage, because the voltage of the electric network also fluctuates, so the transformer with on-load voltage regulation is more suitable for market use. There are periodic fluctuations in power consumption, and the power consumption during peak and low periods is often very different. Therefore, the use of on-load voltage regulation can well solve the problem of power supply stability.

Generally, the voltage regulation of the transformer has three gears and five gears, and each gear can adjust the voltage of 0.5kv. When the transformer is installed, by changing the position of the tap contact, the number of turns of the transformer winding can be changed, thereby changing the output voltage. A commonly used transformer has a primary voltage of 10kv and a secondary voltage of 0.4kv. The first gear of the three-speed distribution transformer is 10.5kv, the second gear is 10kv, and the third gear is 9.5kv, generally in the second gear position.
The steps to adjust the tap changer are as follows:

1. First power off, disconnect the transformer load, use an insulating rod to open the high-voltage drop-out fuse, and then take necessary safety measures to unscrew the transformer.
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Remove the tap-changer cover of the pressurizer and place the positioning pin in the neutral position.

2. When adjusting the gear position, according to the level of the output voltage, adjust the tap changer to only the corresponding position. When the voltage is too low, adjust to the low voltage gear, and when the voltage is too high, adjust to the high voltage gear.

3. After adjusting the gear, measure the DC resistance of each phase winding with a DC bridge, and check whether the DC resistance between each winding is balanced. If the resistance difference between the phases is greater than 2%, it needs to be readjusted. Otherwise, the dynamic and static contacts will heat up or even discharge due to poor contact, which will damage the transformer.