Abstract: A method and an apparatus to recharge a power supply aboard a vehicle which is driven by one or more electric traction motors. The motors are capable of being fed by the power supply aboard the vehicle or by an exterior power supply source through an energy regulating circuit aboard the vehicle. The energy regulating circuit is utilized to feed the electric traction motors and to recharge the power supply aboard the vehicle. The energy regulating circuit operates at a constant rate whereby the energy not absorbed by the one or more electric traction motors is utilized to recharge the power supply aboard the vehicle. A command circuit is associated with the energy regulating circuit to assure that the output of the energy regulating control circuit has a constant current output.