A new power supply for railway cars

THE usual d-c power supply for railway cars consists basically of a battery to which the car load is connected, a d-c generator, and a means of controlling the generator and connecting it to the load. During the last 15 years, a successful system has been established in the general range of 20 to 40 kw. The rotating equipment is a motor-generator set consisting of a d-c generator, a 3-phase 60-cycle 220-volt induction motor, and an armature reversing switch. While the car is in motion, this set is driven from a car axle through a drive unit and clutch. While the car is standing, the set is driven from wayside power through its induction motor.