Operation in the stalled condition represents a stressful special case in the operation of a traction motor drive inverter. When high torque is generated continuously in stall, as for example on a slope, heat builds up in one of the switching devices of one or more phases of the inverter. Research was conducted to develop a method of control that would reduce the heat generated in the switching devices. When the vehicle is stationary on a slope, there is a range of torque for which a vehicle remains stationary, ranging from the minimum torque required to prevent rolling down slope, to the maximum required to overcome static friction and begin propulsion upslope. Focusing on this characteristic, the control was employed so that the traction motor torque command is set to be a minimum in this range, while the torque command has a linear relationship with the accelerator command in other ranges. On the basis of an analysis of vehicle behavior on slopes, it was noted that a range of ineffective torque exists in the stall region of vehicle behavior. An analysis of vehicle hill-climbing behavior showed that there can be a component of torque which is ineffective torque for the action of vehicles in the stall region. The control parameters for suppressing ineffective torque were expanded beyond the stall region to include the point where switching device temperature reaches a maximum. In addition, without changing the torque of the motor, a control technique is applied to reduce heating of the switching devices at the phase where temperature becomes maximum. Conductive duty was reduced in the switching device showing the highest temperature and conductive duty was increased in the switching devices showing lower heat generation in order to obtain uniform heat generation in the devices without changing total motor current. These techniques together have enabled the maximum temperature of the switching device to be reduced by 21.1 deg C.
Method of heat reduction for vehicle traction motor inverter locked at standstill on a climbing slope
Reduzierung der Wärmeentwicklung eines auf einer Steigung zum Stillstand gekommenen Fahrzeugantrieb-Wechselrichters
2004
6 Seiten, 13 Bilder, 4 Quellen
Aufsatz (Konferenz)
Englisch
British Library Conference Proceedings | 2004
|SAE Technical Papers | 2004
|British Library Conference Proceedings | 2004
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