Abstract: An isolation monitor is disclosed in which a switchable bias voltage is imposed on a chassis ground. An isolation voltage is measured when a bias voltage is applied. When there are no electrical faults, the isolation voltage swings up and down to known values. When a fault occurs, the isolation voltage will not to swing to the known values, and thus the isolation resistance can be measured and alarm generated if the isolation resistance falls below a threshold value.

Abstract: An isolation monitor is disclosed in which a switchable bias voltage is imposed on a chassis ground. An isolation voltage is measured when a bias voltage is applied. When there are no electrical faults, the isolation voltage swings up and down to known values. When a fault occurs, the isolation voltage will not to swing to the known values, and thus the isolation resistance can be measured and alarm generated if the isolation resistance falls below a threshold value.

Abstract: A control system for an electric vehicle, such as a golf car, that includes a plurality of power MOSFETs. The vehicle includes a shunt wound motor including an armature coil and a field coil. One of the MOSFETs is connected in parallel across the armature coil and another MOSFET is connected in series with the armature coil. The MOSFET across the armature coil includes a freewheel diode. When the motor is operating below its base speed, i.e., when the back EMF is below the power supply voltage, a current flow can be induced by momentarily turning on the series MOSFET, shorting the armature coil. Because of the residual inductance in the motor, a current flow in the counter clockwise direction is initiated at which point the series MOSFET is turned off. Consequently, a large voltage spike across the motor occurs which results in current flow back into the battery pack. By quickly turning the series MOSFET on and off the current flow can be maintained, and the regenerative braking can occur even at slow speeds.

Abstract: A control system for an electric vehicle, such as a golf car, that includes a plurality of power MOSFETs. The vehicle includes a shunt wound motor including an armature coil and a field coil. One of the MOSFETs is connected in parallel across the armature coil and another MOSFET is connected in series with the armature coil. The MOSFET across the armature coil includes a freewheel diode. When the motor is operating below its base speed, i.e., when the back EMF is below the power supply voltage, a current flow can be induced by momentarily turning on the series MOSFET, shorting the armature coil. Because of the residual inductance in the motor, a current flow in the counter clockwise direction is initiated at which point the series MOSFET is turned off. Consequently, a large voltage spike across the motor occurs which results in current flow back into the battery pack. By quickly turning the series MOSFET on and off the current flow can be maintained, and the regenerative braking can occur even at slow speeds.

Abstract: A control system for an electric vehicle, such as a golf car, that includes a plurality of power MOSFETs. The vehicle includes a shunt wound motor including an armature coil and a field coil. One of the MOSFETs is connected in parallel across the armature coil and another MOSFET is connected in series with the armature coil. The MOSFET across the armature coil includes a freewheel diode. When the motor is operating below its base speed, i.e., when the back EMF is below the power supply voltage, a current flow can be induced by momentarily turning on the series MOSFET, shorting the armature coil. Because of the residual inductance in the motor, a current flow in the counter clockwise direction is initiated at which point the series MOSFET is turned off. Consequently, a large voltage spike across the motor occurs which results in current flow back into the battery pack. By quickly turning the series MOSFET on and off the current flow can be maintained, and the regenerative braking can occur even at slow speeds.

Abstract: A control system for an electric vehicle, such as a golf car, that includes a plurality of power MOSFETs. The vehicle includes a shunt wound motor including an armature coil and a field coil. One of the MOSFETs is connected in parallel across the armature coil and another MOSFET is connected in series with the armature coil. The MOSFET across the armature coil includes a freewheel diode. When the motor is operating below its base speed, i.e., when the back EMF is below the power supply voltage, a current flow can be induced by momentarily turning on the series MOSFET, shorting the armature coil. Because of the residual inductance in the motor, a current flow in the counter clockwise direction is initiated at which point the series MOSFET is turned off. Consequently, a large voltage spike across the motor occurs which results in current flow back into the battery pack. By quickly turning the series MOSFET on and off the current flow can be maintained, and the regenerative braking can occur even at slow speeds.