400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-5760 Web: www.sae.orgSAE TECHNICAL PAPER SERIES 2004-01-0062 Method of Heat Reduction for Vehicle Traction Motor Inverter Locked at Standstill on a Climbing Slope Hiroaki Takanohashi, Satoru Adachi and Takuya Shirasaka Honda R&D Co., Ltd. Tochigi R&D Center Reprinted From: Advanced Hybrid Vehicle Powertrains 2004 (SP-1833) 2004 SAE World Congress Detroit, Michigan March 8-11, 2004Downloaded from SAE International by Univ of Nottingham - Kings Meadow Campus, Saturday, August 11, 2018All rights reserved. No part of this publication ma y be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electroni c, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. For permission and licen sing requests contact: SAE Permissions 400 Commonwealth DriveWarrendale, PA 15096-0001-USAEmail: permissions@sae.orgFax: 724-772-4891Tel: 724-772-4028 For multiple print copies contact: SAE Customer ServiceTel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (outside USA) Fax: 724-776-1615 Email: CustomerService@sae.org ISBN 0-7680-1319-4Copyright © 2004 SAE International Positions and opinions advanced in this paper are those of the author(s) and not necessarily those of SAE. The author is solely responsible for the content of the paper. A process is available by which discussions will be printed with the paper if it is published in SAE Transactions. Persons wishing to submit papers to be considered for presentation or publication by SAE should send the manuscript or a 300 word abstract of a proposed manuscript to: Secretary, Engineering Meetings Board, SAE. Printed in USADownloaded from SAE International by Univ of Nottingham - Kings Meadow Campus, Saturday, August 11, 20182004-01-0062 Method of Heat Reduction for Vehicle Traction Motor Inverter Locked at Standstill on a Climbing Slope Hiroaki Takanohashi, Satoru Adachi and Takuya Shirasaka Honda R&D Co., Ltd. Tochigi R&D Center Copyright © 2004 SAE International ABSTRACT 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. 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 .These techniques together have enabled the maximum temperature of the switching device to be reduced by 21.1 qC. INTRODUCTION In normal operation of a traction motor drive inverter, each phase circuit produces a cyclic output current, with each phase reaching its maximum output current only momentarily. With a synchronous motor, the frequency of this cyclic output is synchronized to the motor speed. When the motor is stalled, this cyclic variation of output current ceases, and the output of each phase is constant. One or more of the phases will put out a current larger than the cycle average or root-mean-square (rms) value. It is possible for one or more phases to be required to put out continuously a current which in normal operation is required only instant