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 2003-01-1329 An Optimized Control Strategy for Parallel Hybrid Electric Vehicle Hyoung-Jin Yoon and Se-Jin Lee Hyundai Motor Company Reprinted From: Virtual Engineer ing, Simulation, & Optimization (SP-1779) 2003 SAE World Congress Detroit, Michigan March 3-6, 2003Downloaded from SAE International by Imperial College London, Saturday, September 08, 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 Imperial College London, Saturday, September 08, 2018 ABSTRACT A systematic process of opt imization is suggested to obtain the best control maps for a parallel type hybrid electric vehicle. Taking the fuel consumption as the cost function and driving cycle as part of the constraints, an optimization problem for CVT pulley ratio control and motor torque control can be formulated. The change of the battery charge state between the start and end point of the given driving cycle also works as a constraint. In order to see the effect of various control strategies on system behavior and overall fuel consumption, a simulation model was built to accommodate the functional blocks representing hybrid powertrain subsystem components and corresponding control units. The aforementioned control strategies were tested and validated on this simulation model and finally tested on a prototype vehicle powered by 1.6 liter gasoline engine and 12kW engine mounted permanent magnet motor to demonstrate the effectiveness of the hybrid system on fuel economy improvement and performance. INTRODUCTION Fuel consumption is not only a matter of fuel cost any more. Together with already known and strictly regulated harmful exhaust emissions such as HC, CO and NO x, CO2 emission draws our concern as a threat to the global environment by its greenhouse effect. Although everyone knows that the reduction of v ehicle weight and friction loss is the essential part, we also have to find a supplementary means of saving fuel. Among the various ideas and schemes of hybridization, parallel electric hybrid system uses the internal combustion engine as the major source of power, together with electric motor assist for high load operation for only limited time. With the peak power assist capability of HEV, we can choose a smaller sized engine for a given vehicle or to choose a larger vehicle for a given engine, thus making the engine and transmission run in more efficient operating region. Besides, electric motor can also convert the deceleration energy to be saved in the battery for later use, thus saving fuel. The goal of this research is to suggest a systematic way to set up a hybrid powertrain control system. OPTIMIZATION ANALYSIS Wheel power for a vehicle operation is det