Power transformer output voltage regulation method

The stability of voltage standard is an important index to measure power quality. In the actual power consumption, due to the large power grid loss, coupled with a large peak-valley difference, low power consumption, easy to cause transformer output voltage fluctuation. The fluctuation of power supply voltage from high to low has great influence on the performance, production efficiency and product quality of various electrical equipment. In order to ensure the qualified rate of the supply voltage, the output voltage of the transformer must be adjusted in time.

The general three-phase transformer is a three-speed or five-speed voltage regulating switch, which can be used to adjust the primary voltage of the transformer.

Steps of transformer voltage regulation:

(1) The power supply is faulty. Disconnect the load on the low-voltage side of the transformer, open the drop fuse on the high-voltage side with an insulating rod, take necessary safety measures, unscrew the protection cover of the transformer tap switch, and place the positioning pin in the zero position. (2) When adjusting gear, adjust tap switch to corresponding position according to the output voltage: when the transformer output value is lower than the allowed value, adjust tap switch from first gear to second gear, or from second gear to third gear. When the transformer output value is higher than the allowable value, the tap switch is adjusted from third to second, or from second to first. (3) After adjusting the gear, measure the DC resistance of each phase winding with a DC bridge to check whether the current between each winding is balanced. If the difference in resistance values between each phase is greater than 2 percent , it must be readjusted. Otherwise, poor contact between dynamic and static contacts after operation will heat up and damage the transformer.