摘要 |
A control means for a series electric motor for, for example, battery operated vehicle usually includes a DC switch for connecting said motor across a battery, a flywheel diode for connecting across the motor and a reverse diode for conducting armature current resulting from regeneration. To avoid overheating when regeneration braking is used on long gradients a resistor is provided in the armature reverse-diode loop in combination with a contactor having a current coil sensitive only to reverse diode current and having normally closed contacts shorting the resistor. |