Replacement method of automatic tap switching device with construction work for the transformer and pole-mounted transformer

摘要

PROBLEM TO BE SOLVED: To provide a transformer with an automatic tap changer for use in construction enabling replacement work of a pole transformer in an uninterruptible state and to provide a replacement method of a pole transformer.SOLUTION: The transformer with an automatic tap changer for use in construction includes: a primary coil 301 connected to distribution lines 101 and 102; a secondary coil 302 connected to a secondary side of a pole transformer 200; a tap changeover part 306 that changes over a tap 303 of the primary coil 301; a secondary voltage detection part 307 that detects voltage of the secondary coil 302; and a controller 305 that performs arithmetic processing and tap changeover control by being input with a current setting tap K3 detected by the tap changeover part 306, a voltage detection value Vbetween secondary coil terminals of the pole transformer 200, and a voltage detection value Vbetween self-secondary coil terminals. The controller 305 estimates a tap 203(K) of the pole transformer 200 by calculating K=K×(V/V) and changes over a tap with the tap changeover part 306 so that the estimated tap coincides a self-setting tap 303(K).