| 摘要 |
A d.c. motor control system, intended primarily for use in battery powered vehicles, includes a control switch (RLa, RLb) for varying the connections of the motor field winding (24) to determine the mode of operation of the motor and speed interlock means for preventing said control switch being operated to change the motor mode whilst the motor is actually running. Instead of using a mechanical speed transducer the speed interlock means includes means for supplying current to the motor field winding (24) when current would not otherwise be flowing therethrough and means (BR1, T<u1>u, P<u16>u etc.) connected to detect the voltage across the armature which occurs in these circumstances if the motor is in motion. |
