Experimental Study on the Effect of Neutral Point Wiring Method on Transformer No-load Current

Abstract

Transformer no-load test is an important test to detect the operating efficiency of the transformer and the presence of defects in the transformer core. When the three-phase regulator is connected to the mains to do the transformer no-load test, it is impossible to avoid the impact of unbalanced output test voltage on the no-load current. To this end, the test studied a 35kV power transformer no-load test, the test power, regulator and transformer neutral point of different connections on the transformer no-load current impact. Analysis of the neutral point of the different connection methods under the no-load current changes, to determine when the regulator neutral point and the power side of the neutral connection, even if the phase voltage unbalance rate of 10% will not affect the no-load current, so that the three-phase regulator to do the transformer no-load test when the neutral point of the best connection. This has some reference value for practical engineering applications.