DIRECT-CURRENT DRIVE Russian patent published in 2001 - IPC

FIELD: DC traction drives. SUBSTANCE: electric drive has first and second current collectors, circuit breaker, input- filter reactor, two input-filter capacitors, smoothing reactor, electric motor incorporating armature winding and field winding, main and auxiliary pulse choppers, starting, braking, auxiliary, and additional contactors, reversing, starting, braking, auxiliary, and three additional diodes, braking, limiting, shunting, additional, ballast, and charging resistors, current sensor, first voltage sensor, control unit, and operating-voltage setting device. Electric drive may be provided with second voltage sensor. As an alternative, control unit may incorporate reference-voltage source, NAND gate, and switch. Maximal braking torque reduces when loads are disconnected or short circuit occurs in contact supply mains. EFFECT: enhanced braking efficiency. 3 cl, 2 dwg