1、HIGH-VOLTAGE DEVELOPMENTS Kevin Jost HIGH-VOLTAGE DEVELOPMENTS Kevin Jost Development of higher-voltage electrical systems in vehicles has been slowly progressing over the past few decades. However, tightening vehicle e ciency and emissions regulations and increasing demand for onboard electrical po
2、wer means that higher voltages, in the form of supplemental 48 V subsystems, may soon be nearing production as the most cost-e ective way to meet regulations. The displacement of high-wattage loads to more e cient 48 V networks is expected to be the next step in the development of a new generation o
3、f mild hybrid vehicles. In addition to improved fuel economy and reduced emissions, 48 V systems could potentially save costs on new electrical features and help better address the emerging needs of future drivers. Challenges to 48 V system implementation remain, leading to discussions by experts fr
4、om leading car makers and suppliers on the need for an international 48 V standard. Initial steps toward a proposed standard have already been taken. So the consensus of global forecasts suggests that 48 V mild hybrids will soon come to dominate the market. Compared with 200-600 V full hybrid and ba
5、ttery electric vehicles, the lower-voltage approach avoids the need for high-cost safety features and large battery packs. . About the Author Kevin is currently the Editorial Director for SAE Internationals Magazines, Books, Videos, and Intellectual Property in Warrendale PA. Prior to that he served
6、 various editorial roles with SAE Magazines including Editor of Automotive Engineering and O -Highway Engineering. His industry experience includes roles as rst Project Engineer for testing and then Product Engineer for seating and other trim systems at Lear Corp. in South eld MI. TU-002 ISBN: 978-0
7、-7680-8192-3 Jost HIGH-VOLTAGE DEVELOPMENTS AUTOMOTIVE48-Volt DevelopmentsFor more information or to order a book, contact: SAE INTERNATIONAL 400 Commonwealth Drive Warrendale, PA 15096 Phone: +1.877.606.7323 (U.S. and Canada only) or +1.724.776.4970 (outside U.S. and Canada) Fax: +1.724.776.0790 Em
8、ail: CustomerServicesae.org Website: books.sae.org Other SAE books of interest Automotive Electronics Reliability, Volume 2 By Ronald K. Jurgen (Product Code: PT-144) Chevrolet VoltDevelopment Story of the Pioneering Electrified Vehicle By Lindsay Brooks (Product Code: PT-149) Automotive E/E Reliabi
9、lity By John Day (Product Code: T-126) Electric and Hybrid-Electric Vehicles By Ronald K. Jurgen(Product Code: PT-143.SET)Warrendale, Pennsylvania, USA Edited By Kevin Jost 48-Volt Developments Copyright 2016 SAE International. eISBN : 978-0-7680-8271-5 400 Commonwealth Drive Warrendale, PA 15096 E-
10、mail: CustomerServicesae.org Phone: +1.877.606.7323 (inside USA and Canada)+1.724.776.4970 (outside USA) Fax: +1.724.776.0790 Copyright 2016 SAE International. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, distributed, or transmitted, in any form o
11、r by any means without the prior written permission of SAE International. For permission and licensing requests, contact SAE Permissions, 400 Commonwealth Drive, Warrendale, PA 15096-0001 USA; e-mail: copyrightsae.org; phone: 724-772-4028; fax: 724-772-9765. Printed in the United States of America L
12、ibrary of Congress Catalog Number 2015953673 SAE Order Number TU-002 http:/dx.doi.org/10.4271/tu-002 Information contained in this work has been obtained by SAE International from sources believed to be reliable. However, neither SAE International nor its authors guarantee the accuracy or completene
13、ss of any information published herein and neither SAE International nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SAE International and its authors are supplying information, but
14、are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. ISBN-Print 978-0-7680-8192-3 ISBN-PDF 978-0-7680-8271-5 ISBN-epub 978-0-7680-8273-9 ISBN-prc 978-0-7680-8272-2 To purchase bulk quan
15、tities, please contact: SAE Customer Service E-mail: CustomerServicesae.org Phone: +1.877.606.7323 (inside USA and Canada)+1.724.776.4970 (outside USA) Fax: +1.724.776.0790 Visit the SAE Bookstore at BOOKS.SAE.ORGv Introduction .ix Chapter 1 Fuel Consumption and Emissions Effects in Passenger Car Di
16、esel Engines through the Use of a Belt Starter Generator 1 Drivetrain Architecture .2 Methods .4 Thermodynamic Optimisation 4 Automated Cycle Driving 4 Hybrid Operating Strategy .7 Results and Discussion 14 Conclusions .19 References 21 Chapter 2 Requirements and Protection within a 48V Automotive W
17、iring System . 23 Weight Saving Issues and Topology of a Multi-Voltage Wiring System 24 Operating Safety for the 48V Wiring System .25 Protection Concepts for the Different Arc Types .27 Conclusions .30 Chapter 3 Mixed Voltages and Aluminum Conductors: Assessing New Electrical Technologies . 31 Inte
18、grating Flow for 48V System Components and Aluminum Wires 32 Build 48V Components into a 12V Vehicle System .32 Verification of a Mixed Voltage System 34 Replacement of Copper with Aluminum Wires 35 Examine the Results of all Recommended Changes .36 Summary .37 References 37 Table of Contents vi Cha
19、pter 4 Hybrid Cars Setting New Challenges for Optimized Power Semiconductors . 39 The Variety of Battery Voltages for Plug-In Vehicles - xEVs 40 Voltage Classes of the Semiconductors Tailored to the Application 42 Simulation of a 12V ABS System .42 Simulation of a 12V Engine Cooling Fan 43 Dc-dc Con
20、verter Simulation of 250V/400V .44 Summary .45 Semiconductors Tailored to Different Voltage Classes .46 Conclusion 51 Chapter 5 Specification and Design of a Switched Reluctance 48 V Belt Integrated Starter Generator (B-ISG) for Mild Hybrid Passenger Car Applications. 53 Electrical Implementation of
21、 48V systems .54 V ehicle Architecture Layouts 55 Small Vehicle Segment 55 Large Vehicle Segments.56 Application Specific Motor Requirements .57 Motor Design Challenges58 Traditional Switched Reluctance Machine Challenges .61 Torque, Voltage and Current Ripple .61 Noise, Vibration, and Harshness .62
22、 Electronics Costs 63 Diverging Solutions with a Common Core 64 Winding Variants .64 Electronics Variants .64 Control Systems and Modelling Variants .64 SpeedStart Performance Data.65 Energy Storage 66 Conclusions .67 References 68 Chapter 6 Optimizing Lithium-Ion Batteries - Tailoring Electrodes fo
23、r Microhybrid Vehicle Applications. 69 Experimental .70 Drive Cycles Used in this Work .70 Vehicle Simulation .71 Electrochemical Simulation 72vii Results 73 Defining Metrics and Targets for Microhybrid 73 Energy Density .74 Power Density 75 Combining Fuel Economy and Volume .76 Limiting Constraints
24、 for Electrode Sizing 78 Fundamental Limitation of Charge Acceptance .78 Customizing Electrodes for Intended Life .79 Varying Conditions Over Battery Life 79 Varying Vehicle-Level Requirements Over Battery Life 80 Optimizing Electrodes for Microhybrid .82 Customizing Electrodes for Cell Capacity .82
25、 Effects due to Motor/Generator Size .84 Customizing Electrodes for Drive Cycles 84 Discussion .86 Analysis of the Wh recov /L Metric 86 Applicability of WH recov /L Metric .86 Variants of the Wh recov /L Metric 87 Impacts of Vehicle Requirements 87 Definition of Battery Life 87 V ehicle Architectur
26、e Changes 88 Drive Cycle Impacts 89 Summary and Conclusions .89 Impact of Quantitative Optimization .89 Other V ehicle Applications .89 References 90 Chapter 7 Application of 48 Volt for Mild Hybrid Vehicles and High Power Loads . 93 Characteristics and Requirements of the 48V E/E System 94 Failure
27、Modes in the 14V/48V E/E System .95 Short to Ground .95 Loss of Common Ground .96 Voltage Short Circuit .96 Broken Wire 97 Recommendations for 48V E/E System design .100 Battery Box 100 Power Distribution Boxes .100 Pre-Fuse Boxes .100 Bused Electrical Centers .101Electric/Electronic Centers (Smart
28、E/E Centers) .101 Electronic Modules (dc-dc converters) .101 Wires for 48V Application 101 Routing .102 Materials .102 Color Coding 102 Connection Systems for 48V Application .102 Avoidance of Hot Plugging 103 Component Level .103 System Level 103 Summary and Conclusions .104 References 104 Acknowle
29、dgments .104 Chapter 8 Advantages of a 48 Volt Belt Starter Generator in an Ultra-Light Vehicle Powertrain 105 CULT - Cars Ultra-Light Technology 106 Hybrid Approach - 12 V BSG .107 BSG (12 V) Hybrid Configuration .107 Validation Process 108 CO 2Saving Potentials and Comfort 109 Hybrid Approach - 48
30、 V BSG .112 Introduction of 48 V Technology .112 BSG (48 V) Hybrid Configuration .113 Electric Driving Potential 115 Energy Management .118 CO 2Saving Potentials 121 48 V Plug-In Concept 123 Summary .123 References 124 Acknowledgments .125 About the Editor .127 viii High-voltage developments: a 48 V
31、 technical update The concept of higher-voltage electrical systems in vehicles, which has evolved from 12 V conventional systems to include 200 V and 600 V full hybrids and electric vehicles, is not new, with development experiencing fits and starts over the past few decades. However, tightening veh
32、icle efficiency and emissions regulations and increasing demand for onboard electrical power means that higher voltages, in the form of supplemental 48 V subsystems, may soon be nearing production. One sign of this was on display at the 2014 Los Angeles Auto Show. The Audi Prologue show car, which p
33、rovided a preview of the companys design future, also more quietly previewed a new 48 V electrical subsystem coming to future Audi products. The company attributed some of the large show cars relatively low fuel consumption and CO 2emissions to the new 48 V electrical system. Powered by a belt start
34、er generator, the set up enables mild powertrain hybridization with brake-energy recovery in the Prologue. The displacement of high-wattage loads to more efficient 48 V networks is expected to be the next step in the development of a new generation of mild hybrid vehicles. In addition to improved fu
35、el economy and reduced emissions, 48 V systems could potentially save costs on new electrical features and help better address the emerging needs of future drivers. A new report from Autelligence, called “48 V and automotive electrificationsystems, performance and opportunity,” analyzes the technolo
36、gy in detail and provides an outlook on future market introductions. The new technology is “extremely economical because it can be easily integrated into an existing vehicle architecture, and the small 48-volt battery means battery costs are reasonable,” said Christopher Breitsameter, Head of Busine
37、ss Development and Strategy, Continental Powertrain Division. Challenges to 48 V system implementation remain. At the 2nd International Conference on Advanced Automotive 48 V Power Supply Systems organized by IQPC Automotive in Dsseldorf last November, experts from leading car makers and suppliers d
38、iscussed the need for ix an international 48 V standard. Initial steps already have been taken for the adoption of the LV148 standard proposed by Audi, BMW, Daimler, Porsche, and Volkswagen. It makes sense to have a common global standard, according to Paul Bloore, Product Validation Manager for Con
39、trolled Power Technologys hybrid product group, because 48 V hybrids are currently the most cost- effective way of meeting stringent CO 2emissions in the buildup to 2020 European regulations. This is compounded, potentially, by a shift from the current NEDC to the more aggressive WLTP test, with fur
40、ther 25% reductions anticipated in 2025 and 2030. Electric turbo and supercharging could benefit from 48 V networks. Hyundai and Kia are said to be developing a mild-hybrid diesel powertrain using an electric supercharger in conjunction with a 48 V network. According to Bloore, electric boosting usi
41、ng energy recuperated, rather than lost in friction from the brakes, not only reduces CO 2and NOx emissions, but can also have a positive impact on vehicle performance and drivability. The rapidly growing interest in 48 V networks was also discussed at the SAE International 2015 Hybrid & Electric Ve
42、hicles Technologies Symposium held in Los Angeles in February. Dr. Mazen Hammoud, Fords Chief Engineer for Electrified Powertrain Systems and SAE Fellow, said that the 48 V working voltage is the best compromise for mild hybridization. (See http:/articles.sae.org/13908/.) Although the higher voltage
43、 provides no real electric-only drive capability, there is better capacity for capturing braking regeneration energy, up to about 60% of that available, and it is a good stop-start enabler, Hammoud said. A mild hybrid can provide more than 3% increased engine-off time versus a 12 V stop-start vehicl
44、e in real-world driving conditions. In addition, according to ECE-R 100 regulations for dc voltages under 60 V , shock protection is not required for 48 V , helping to lower cost. So the consensus of global forecasts suggests that 48 V mild hybrids will soon come to dominate the market. Compared wit
45、h 200-600 V full hybrid and battery electric vehicles, the lower-voltage approach avoids the need for high-cost safety features and large battery packs. CPT estimates that if 48 V technology and related emissions-reduction strategies could be x universally applied to the more than 100 million vehicl
46、es forecast to be produced per year from 202098% of them with gasoline and diesel enginesannual CO 2emissions could be reduced by 100 million t (110 million ton) globally per year. The Audi Prologue mild-hybrid concept cars 48 V electrical system showing energy flow for comfort features during idle-
47、stop. The Audi Prologue mild-hybrid concept cars 48 V electrical system showing energy flow during brake-energy recuperation. xi Pic 2: Developed by Kias European R&D Center, its “future technology” diesel hybrid system employs a 48 V lead-carbon battery, which powers a small electric motor to incre
48、ase the engines output and cut exhaust emissions. Its Valeo electric supercharger was developed by Controlled Power Technologies. In this technical update The papers in this collection focus on various aspects of 48 V engineering development, including system design, integrated starter generators, w
49、iring, conductors, power semiconductors, optimized batteries, high power-load considerations, and integration within a highly efficient vehicle. In 2015-01-1162, researchers at Continental and Technische Universitaet Darmstadt take a look at “Fuel consumption and emissions effects in passenger car diesel engines through the use of a belt starter generator.” Modern vehicles need to fulfil ch
