Case Analysis of Abnormal Secondary Circuits in Voltage Transformers
1. Fault SituationIn September 2023, as a front - line fault maintenance worker, I detected abnormal voltage on the 10kV Section I bus of a substation during monitoring duty and informed the operation and maintenance team. The monitoring system showed: U0 = 0 kV, Ua = 6.06 kV, Ub = 5.93 kV, Uc = 6.05 kV, Uab = 10.05 kV, Ubc = 5.94 kVMy team and I rushed to the site. We suspected the secondary air circuit breaker of the 10kV Section I bus voltage transformer was closed and found the U - phase fus