1、_ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2013 SAE International All rights reserved. No part of this p
3、ublication 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. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-497
4、0 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/J2982_201306 SURFACE VEHICLE RECOMMENDED PRACTICE J2982 JUN2013 Issued 2013-06 Ri
5、ding Range Test Procedure for On-Highway Electric Motorcycles RATIONALE This Recommended Practice has been developed to provide a reasonable and consistent basis for manufacturers of on-highway electric motorcycles to inform prospective owners of the riding range that can be expected under specified
6、 operating conditions. FOREWORD This Recommended Practice establishes a chassis dynamometer-based procedure for measuring the riding range of on-highway electric motorcycles under several different operating conditions. A “City” range test is specified to determine riding range during “stop-and-go”
7、operation. Constant speed tests at 55 mph and 70 mph are specified to determine riding range during uncongested highway operation at two different cruising speeds. A “Highway Commuting” range calculation procedure is specified to determine riding range in urban areas when operation consists of 50% s
8、top-and-go operation and 50% operation on urban freeways under levels of congestion that allow for quasi-steady speeds of 55 to 70 mph. INTRODUCTION Since model year 1972, the U.S. Environmental Protection Agency (EPA) has specified the use of the Urban Dynamometer Driving Schedule (UDDS) to determi
9、ne compliance with exhaust emission standards for passenger cars and light-duty trucks. Beginning in model year 1978, the UDDS was also the driving cycle specified to determine the “city” fuel economy used to determine compliance with the Corporate Average Fuel Economy Standards for passenger cars.
10、Also beginning in model year 1978, the UDDS was the driving schedule specified for testing exhaust emissions from highway motorcycles with engines 169 cubic centimeters (cc) displacement. (A modified version of the driving cycle with reduced speeds was specified for motorcycles 2 mph from the trend)
11、 should be discarded, being careful to retain the same number of runs in each direction in the final data set. It is convenient to assign a time of 0.0 to the final value above 100 km/h for each coastdown run. To calculate coastdown times, fit the time versus speed results to second-order polynomial
12、 equations in the form time = a + b*speed + c*speed2. Use these equations to calculate the time for 55 mph and for 45 mph, and subtract the two values to obtain the coastdown time for each run. Compute the arithmetic average coastdown time to arrive at the dynamometer target coastdown time. Example
13、using 5 Hz speed data in mph: Time: 0.0 0.2 0.4 0.6 0.8 23.6 23.8 24.0 24.2 Speed: 62.03 61.53 60.91 60.25 59.74 30.75 30.52 30.19 29.78 FIGURE A-1 - PLOT OF SPEED VS. TIME FROM COASTDOWN y = 0.010886x2- 1.762208x + 67.257797 05101520253020 30 40 50 60 70time (sec)Speed (mph) SAE J2982 Issued JUN201
14、3 Page 12 of 12 Calculating times for 55 mph and 45 mph: t55= 0.010886*55*55-1.762208*55+67.257797 = 3.267sec t45= 0.010886*45*45-1.762208*45+67.257797 = 10.003sec Coastdown time for 55 to 45 mph: 10.003 - 3.267 = 6.736sec A.6 DYNAMOMETER COAST DOWNS Dynamometer power settings which duplicate the av
15、erage road coastdown time are found by varying the power setting while performing repeated wheel-down coastdowns on the dynamometer. The cold tire pressure must be set to the same value as used on the road. The vehicle must be warmed up on the dynamometer for 30 min at 80 km/h. The recommended appro
16、ach is to perform at least three dynamometer coastdowns at five different power settings. The road coastdown time must be bracketed by the dynamometer coastdown times resulting from the power settings used. Calculate inverse time (1/Coastdown time), then average the times at each power setting. Plot the power settings versus average inverse time and determine the power setting that matches the road coastdown time.
