400 Commonwealth Drive, Warrendale, PA 15096-0001 U.S.A. Tel: (724) 776-4841 Fax: (724) 776-5760 Web: www.sae.org SAE TECHNICAL PAPER SERIES 2003-01-0084 Electric Machine Powertrain Integration for GM’s Hybrid Full-Size Pickup Truck David G. Evans and Keith D. Van Maanen General Motors Powertrain Reprinted From: Advanced H ybrid Vehicle Powertrains 2003 (SP-1750) 2003 SAE World Congress Detroit, Michigan March 3-6, 2003Downloaded from SAE International by Univ of California Berkeley, Thursday, August 02, 2018All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise,without the prior written permission of SAE. For permission and licensing requests contact: SAE Permissions 400 Commonwealth DriveWarrendale, PA 15096-0001-USAEmail: [email protected]: 724-772-4028Tel: 724-772-4891 For multiple print copies contact: SAE Customer ServiceTel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (outside USA)Fax: 724-776-1615Email: Customer [email protected] ISSN 0148-7191Copyright © 2003 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 pap er if it is publishe d in SAE Transactions. Persons wishing to submit papers to be considered for presentation or publication by SAE should send themanuscript or a 300 word abstract of a proposed manuscript to: Secretary, Engineering Meetings Board, SAE. Printed in USADownloaded from SAE International by Univ of California Berkeley, Thursday, August 02, 20182003-01-0084 Electric Machine Powertrain Integration for GM’s Hybrid Full-Size Pickup Truck David G. Evans and Keith D. Van Maanen General Motors Powertrain Copyright © 2003 SAE International ABSTRACT General Motors plans to introduce a hybrid version of its popular light-duty full-size (Silverado/Sierra) pickup truck. The program imperative of minimal vehicle architecture change drove a highly integrated powertrain solution. The hybrid powertrain features a novel, compact method of integrating an electric motor/generator between the largely unchanged engine and transmission, preserving their locations. From the targeted hybrid functions, power and energy specifications are derived. Specific design aspects and performance examples relating to the motor/generator packaging, torque converter, and overall vehicle driveabiltiy are discussed. INTRODUCTION Polom, Evans, Poulos, Van Maanen, and Zarger1 explain the process GM followed to architect the “Parallel Hybrid Truck” (PHT). From the rolldown of program requirements to product concept to powertrain requirements, a compact configuration of an electric machine (motor and generator) mounted between the engine and transmission emerged as the superior choice. The fundamental electric machine (EM) integration into a zero-space allotment within the powertrain required an unconventional downsized torque converter – a patented GM exclusive 2. A systematic balance of 1) packaging, 2) torque converter thermal performance, and 3) vehicle driveability required clarification of the root problems or challenges, design solutions, and proof-of-performance verification (Figure 1). This format is used throughout the body of this discussion. This unusual pairing of a powerful truck 5.3L V8 engine and a downsized torque converter presented various challenges. For operation in the normal torque-multiplying mode where slip speed occurs between the hydrodynamic pump and turbine, the torque converter thermal performance was a critical issue. Additionally, creep, launch feel, and acceleration times were investigated carefully against traditional requirements, and in some cases, new assessment methods were created to address the expande