| 摘要 |
1446105 Control of two D.C. motors LICENTIA PATENT - VERWALTUNGS - GmbH 19 Sept 1974 [19 Sept 1973] 40962/74 Heading H2J D.C. motors 5, 6 are mechanically coupled to the drive of a refrigerating unit for a railway wagon and, according to the stopping place of the wagon, are energized by various A.C. or D.C. voltages occurring on an overhead supply line 1, the supply to the motors comprising an autotransformer 13 feeding a rectifier bridge 14 and a number of switches 8, 11, 12, 19 ... 25, whose sequence of operation is such that the motors are supplied through members 13, 14 when A.C. is present on the line 1 and through the bridge 14 when D.C. is present, the bridge elements 15 ... 18 also serving to prevent power feedback from the motors to the line 1. Operation is described for line voltages of 1KV, 16<SP>2</SP>/ 3 HZ, A.C., 1À5 KV, 50 HZ, A.C., 1À5 KV, D.C. and 3 KV, D.C., a main contactor 3 being closed for all these voltages and the abovementioned switches 8 to 25 being opened or closed as follows: (1) 1À5 KV, 50 HZ, A.C. 8, 11 and 25 open and the remainder closed to connect the motors in parallel across the bridge 14 supplied via transformer tap a; (2) 1KV, 16<SP>2</SP>/ 3 HZ, A.C. 8, 12 and 25 open and the remainder closed to provide a parallel connection as in (1) above via transformer tap b; (3) 1À5 KV, D.C. 8, 19, 24, 25 closed and the remainder open to connect the motors in parallel to earth 26 through respective pairs of elements 15, 17 and 16, 18; (4) 3 KV, D.C. 8, 20 and 25 closed and the remainder open to connect the motors in series to earth 26 through elements 15 ... 18 all in series. |
