A METHOD FOR FEEDING HOTEL LOAD IN A TRAIN BY TAP CHANGER CONTROLLED LOCOMOTIVE TRANSFORMERS

摘要

The regulating transformer (R) which draws power at 25 KV from the traction overhead line is divided into 32 parts that corresponds to 32 voltage steps. The output of the regulating transformer is fed to main transformer (M) which has an arrangement of one primary winding (P1, P2) and two secondary winding (S1, S"1 and S2, S"2). A single magnetic circuit is arranged for both the transformers (R) and (M). The flux of the Main transformer changes with change of tappings. But the magnetic flux (ΦR) in the regulating transformer (R) remains constant which generates additional voltage source for the Hotel load winding. Owing to the constant flux this voltage constant at all the speed (tap position) of the train. This voltage output is converted to D C by means of rectifiers and this D C power is utilized to meet the hotel load requirements.