ISO16750-3-2012
ISO16750-3-2012Road vehicles — Environmentalconditions and testing for electricaland electronic equipment —Part 3:Mechanical loadsContents PageForeword.............................................................................................................................................Iso16750-3:2012[EContentsPageForewordScope12Normative references1Terms and definitions4Tests and requirements4.1ibration4.2 Mechanical shock274.3 Free fall…294.4 Surface strength/ scratch and abrasion resistance294.5 Gravel bombardmentCode letters for mechanical loads29Documentation…,…………111111130Annex A (informative) Guideline for the development of test profiles for vibration tests.32Annex B (informative) Recommended mechanical requirements for equipment depending on themounting location44Bibliography46C ISO 2012-All rights reservedIso16750-3:2012EForewordISo (the International Organization for Standardization) is a worldwide federation of national standardsbodies (Iso member bodies). The work of preparing International Standards is normally carried outthrough iso technical committees. Each member body interested in a subject for which a technicalcommittee has been established has the right to be represented on that committee. Internationaorganizations, governmental and non-governmental, in liaison with ISO, also take part in the workIso collaborates closely with the International Electrotechnical Commission (IEC) on all matters ofelectrotechnical standardizationInternational Standards are drafted in accordance with the rules given in the ISo/IEC Directives, Part 2The main task of technical committees is to prepare lnternational standards. draft InternationalStandards adopted by the technical committees are circulated to the member bodies for votingublication as an International Standard requires approval by at least 75 of the member bodiescasting a voteAttention is drawn to the possibility that some of the elements of this document may be the subject ofpatent rights. ISO shall not be held responsible for identifying any or all such patent rightsIso 16750-3 was prepared by Technical Committee ISO/TC 22, Road vehicle, Subcommittee SC 3,Electrical and electronical equipment.This third edition cancels and replaces the second edition (Iso 16750-3: 2007), which has beentechnically revisedISo 16750 consists of the following parts, under the general title road vehicles-Environmental conditionsand testing for electrical and electronic equipment:Part 1: GeneralPart 2: electrical loadsPart 3: Mechanical loadsPart 4: Climatic loadsPart 5: chemical loadso ISO 2012-All rights reservedINTERNATIONAL STANDARDIso16750-3:2012(E)Road vehicles- Environmental conditions and testing forelectrical and electronic equipmentPart 3Mechanical loads1 ScopeThis part of IS0 16750 applies to electric and electronic systems/components for road vehicles. Itdescribes the potential environmental stresses and specifies tests and requirements recommended forthe specific mounting location on/in the vehicleThis part of iso 16750 describes mechanical loads2 Normative referencesThe following referenced documents are indispensable for the application of this document. For datedreferences, only the edition cited applies For undated references, the latest edition of the referenceddocument (including any amendments applies.Iso16750-1, Road vehicles- Environmental conditions and testing forelectrical andelectronicequipment-Part 1: GeneralIEC 60068-2, 6, Environmental testing- Part 2-6: Testing, Test Fc: Vibration SinusoidalIEC60068-2, 14, Basicenvironmental testing procedures- Part 2-14: Tests-Test Nb: Change oftemperatureTEC 60068-2, 64, Environmental testing Part 2-64: Test methods -Test Fh -Vibration, broad-bandrandom(digital control)and guidanceIEC 60068-2, 80, Environmental testing- Part 2-80: Tests- Test Fi: Vibration - Mixed mode testingIEC 60068-2-31, Environmental testing procedures- Part 2: Tests; Test Ec: Free fall, Clause 5.23 Terms and definitionsFor the purposes of this document, the terms and definitions given in Iso 16750-1 app4 Tests and requirements4.1 Vibration41.1 GeneralThe vibration test metho ds specified consider various levels of vibration severities applicable to on-board electrical and electronic equipment. It is recommended that the vehicle manufacturer andsupplier choose the test method, the environmental temperature and vibration parameters dependingon the specific mounting locationFollowing the expressions in MIL-STD please noticeC ISO 2012-All rights reservedIso16750-3:2012EWhen applied properly, the environmental management and engineering processes described in this partof Iso 16750 can be of enormous value in generating confidence in the environmental worthiness andoverall durability. However, it is important to recognize that there are limitations inherent in laboratorytesting that make itimperative to use proper caution and engineering judgement when extrapolating theselaboratory results to results that may be obtained under actual service conditions. In many cases, realworld environmental stresses (singularly orin combination cannot be duplicated practically or reliably intestlaboratories. Therefore, users of this part of Iso 16750 should not assume that a system or componentthat passes laboratory tests of this part of Iso 16750 would also pass field/ fleet verification trialsThe specified values are the best estimation one can get up to the moment when results frommeasurements in the car are received - but they do not replace a car measurement!The specified values apply to direct mounting in defined mounting locations. Using a bracket formounting can resultin higher or lower loads. If the device under test ( DUT)is used in the vehicle with abracket then all vibration and mechanical shock test shall be done with this bracketCarry out the vibration with the dut suitably mounted on a vibration table. The mounting method (sused shall be noted in the test report. Carry out the frequency variation by logarithmic sweeping of 0,5octave/minute for sinusoidal tests and the sinusoidal part of sine on random tests. The scope of therecommended vibration tests is to avoid malfunctions and breakage mainly due to fatigue in the fieldTesting for wear has special requirements and is not covered in this part of ISo 16750Loads outside of the designated test frequency ranges are to be considered separatelNOTE Deviations from the load on the DUT can result, should vibration testing be carried out according tothis part of Iso 16750 on a heavy and bulky dut, as mounting rigidity and dynamic reaction on the vibrator tableexcitation are different compared to the situation in the vehicle. This deviation can be minimized by applying theaverage control method(see Annex A)Application of the weighted average control method according to IEC 60068-2, 64 is to be agreed uponSubject the dut during the vibration test to the temperature cycle according to iEC 60068-2, 14, withelectric operation according to diagram 1. Alternatively, a test at constant temperature may be agreed onOperate the dutelectrically as indicatedin Figure l at Tmin(Short functional testafterthe dUT completelyreached Tmin). This functional test shall be as short as possible- only long enough to check the properperformance of the dUt. This minimizes self-heating of the dUT. Additional electrical operation of theDUT between 210 min and 410 min of the cycle (see Figure 1)Additional drying of test chamber air is not permittedIn the vehicle, vibration stress can occur together with extremely low or high temperatures; for thisreason, this interaction between mechanical and temperature stress is simulated in the test, too. afailure mechanism is, for example, a plastic part of a system/component, which mellows due to the hightemperature and cannot withstand the acceleration under this condition2o ISO 2012-All rights reservedIso16750-3:2012[EYmax20aburditt0100200300400500600yY temperature[°C]x time [ minIa Operating mode 3.2 according to ISo 16750-1.b Operating mode 2. 1 according to ISo 16750-1One cycleFigure 1-Temperature profile for the vibration testTable 1- Temperature versus time for the vibration testTimeTemperaturemin°C0206040150-4021020300max41048020See Is016750-44.1.2 Tests4.1.2.1 Test I- Passenger car, engine4.1.2.1.1 PurposeThis test checks the dUt for malfunctions and breakage caused by vibrationThe vibrations of a piston engine can be split up into two kinds: Sinusoidal vibration which results from theunbalanced mass forces in the cylinders and random noise due to all other vibration-schemes of an engine,C ISO 2012-All rights reserved3Iso16750-3:2012Ee.g. closing of valves. In the lowest frequency range from 10 Hz to 100 Hz the influence of rough-roadconditions is taken into account. The main failure to be identified by this test is breakage due to fatigueNOTE 1 Road profile usually has negligible impact on engine-mounted components. Shock inputs are effectivelysolated by suspension, and engine-mounting systemsThe test profiles specified in the following clauses apply to loads generated by(four strokereciprocating enginesNotE 2 If the dut is to be tested for a specific resonance effect, then a resonance dwell test according to 8.3.2of IEC 60068-2, 6: 2007 can also be applied4.12.1.2Test4.1.2.1.2.1 GeneralIt is required to perform this test as a mixed mode vibration test according to IEC 60068-2, 80NOTE The test duration is based on A 4. The temperature in the chamher is above room temperature (rt)atthe end of the test (2 3/4 temperature cycles4.1.2.1.2.2 Sinusoidal vibrationPerform the test according to IEC 60068-2, 6, but using a sweep rate of s 0,5 octave/minute. Use a testduration of 22 h for each plane of the dUTUse curve l in Table 2/ Figure 2 for DUT intended for mounting on engines with 5 cylinders or fewerUse curve 2 in Table 2/Figure 2 for dUT test intended for mounting on engines with 6 cylinders or moreBoth curves may be combined to cover all engine types in one test2502001501005050100150200250300350400450500ⅩKeyamplitude of acceleration [m/s2IXfrequency [Hzcurve1(≤5 cylinders)curve 2(5 cylindersFigure 2- Vibration severity curves4o ISO 2012-All rights reservedIso16750-3:2012[ETable 2- values for max acceleration versus frequencyCurve 1(see Figure 2FrequencyAmplitude of accelerationHz100100200200240200270100440100Curve 2(see Figure 2)FrequencyAmplitude of accelerationHm/s2100100150150440150CombinationFrequencyAmplitude of accelerationH1001001501502002002402002551504401504,1.21.2.3 Random vibrationPerform the test according to IEC 60068-2, 64. Use a test duration of 22 h for each plane of the DUTThe r.m.s. acceleration value shall be 181 m/s2The psd versus frequency are referred to in Figure 3 and Table 3NoTE The Power Spectral Density(PSD)values (random vibration] are reduced in the frequency range of thesinusoidal vibration testC ISO 2012-All rights reserved5Iso16750-3:2012EY100100,110100100010000KeyY PSD [(m/s2)2/HzX frequency [Hz]Figure 3- PSD of acceleration versus frequencyTable 3- Values for frequency and PsDFrequencyPSDH:(m/s2)2/Hz1010100103000,5150020200024.1.2.1.3 RequirementBreakage shall not occur.Functional status a see iso 16750-1) is required during operating mode 3.2 as defined in ISo 16750-1and functional status C during periods with other operating modes4.1.2.2 Test II-Passenger car, gearbox4.1.2.2.1 PurposeThis test checks the dut for malfunctions and breakage caused by vibrationThe vibrations of a gearbox can be split up into two kinds which result partly from sinusoidal vibrationfrom unbalanced mass forces of the engine(e. g dominating orders) in the frequency range from 100 Hzto 440 Hz and vibration from the friction of the gear wheels and other schemes, which are tested in therandom part. In the lowest frequency range from 10 Hz to 100 Hz the influence of rough-road conditionsis taken into account The main failure to be identified by this test is breakage due to fatigueChanging the gears can create additional mechanical shock and shall be considered separatey brationsThe test profiles specified in the following subclauses apply to loads generated by gearbox vibo ISO 2012-All rights reserved
- 2020-12-08下载
- 积分:1
matlab模型预测控制
介绍MPC,简介预测控制动态矩阵能直接处理带有纯滞后的对象,对大惯性有很强的适应能力,又有良好的跟踪性能和较强的鲁棒性,并且对模型精度要求低,所以在工业过程中有很强的适用性。本文针对DMC算法进行研究,并在此基础上用matlab进行了系统仿真验证了该算法的优点。口经验交流口仪器仪表用户P已知的情况下,控制时域长度M越小,越难保证输出在各采能的 Window标准图形用户界面,使优化问题操作简单方便。样点紧密跟踪期望输出值,系统的响应速度比较慢,但容易得在 Matlab制作图形用户界而(GUI)的设计环境下,用M文件到稳定的控制和较好的鲁棒性;控制时域长度M越大,控制来进行CU编程,使GU设计变得简单、快捷。的机动性越强,能够改善系统的动态响应,增大了系统的灵活首先在Meab的命令窗下输人 guide命令或者利用文件性和快速性,提高控制的灵敏度,但是系统的稳定性和鲁棒性菜单中的new选项下的GUI,即可以进入CUI设计窗口。从变差。因此,控制时域长度的选择应兼顾快速性和稳定性。窗口的左侧工具栏中选取需要的控件,绘制在右侧锥形窗口;4)控制加权系数双击各控件图标,即打开该控件属性对话框,对其进行属性设控制加权系数主要用于限制控制增量的剧烈变化,使控置。保存图形界面时,系统将直动生成一个同名的m文件,打制量的变化趋于平缓,以防止超出限制范围或发生剧烈振荡,开此程序文件,对图形界面各控廾的回调函数 Callback()增减少对系统的过大冲击。增加控制值加权系数的值,控制作加所需的程序代码,以完成各种操作。设计完成之后的得到用减弱,闭环系统稳定,输出响应速度减慢,有益于增加系统的界面如图4所示。的稳定性;但过人的控制加权系数会使控制量的变化极为缓动态矩阵控制算法仿真慢,系统得不到及时的调节,反而会使动态特性变坏7。拴制牌出图积样周期预測时域斑度「F动态矩阵控制算法的优点I)直接在控制算法中考虑预测变量和控制变量的约束条控制时域长度M=1件,用满足约束条件的范围求出最优预测值输入戏象横型控淛权系数2)把控制变量与预测变量的权系数矩阵作为设计参数,系统设定值在设计过程中通过仿真调节鲁棒性好的参数值。3)预测变量和控制变量较多的场合,或者控制变量的的设定在给出的目标值范围内,只是具有自由度,预测变量的定图4动态矩阵控制算法界面设计常状态值被认为是有无数组组合。5结束语4)从受控对象动态特性设定到最后作为仿真来确定控制性由上述仿真结果可以知道,动态矩阵控制效果比传统能为止。DMC算法以直接作为控制量,在控制中包含了数字积PID的控制效果好。动态矩阵控制采用工程上容易得到的阶分环节,因此,即使在模型失配的情况下,也能得到无静差控制。跃响应作为数学模型、运算量小、算法简单、在线实时方便,具4仿真研究有良好的调节品质和很强的鲁棒性,能抑制被控对象的大迟针对被控对象C(s)=12滞特性,能够满足生产现场的需要,获得满意的控制效果,因17.2s+进行仿真,取采样周期而有良好的应用前景。同时基于 Matlab汝计实现了动态矩阵T=2s,模型时域长度为N=90,预测时域长度P=6,控制时控制算法图形用户界面,为动态矩阵控制算法提供了一个简域长度M=1,控制权系数A=1,系统设定值y,=1。对模型在单实用的平台。由于 Matlab具有良好、开放的可扩展性,在应用阶跃扰动下进行仿真,得到如图2所示的控制曲线,可以知道中,用户可以根据实际问题编写相应的函数文件,在CU平台输控制效果较好。入要修改的参数即可完成优化求解操作简单、非常实用。口与传统的PID控制器的控制效果进行比较,其中传统参考文献PD的参数采用工程整定法中的动态特性参数法(又称Z-NL1]李国勇.智能控制及其 MATLAB实现[M]北京:电子工业整定法),得到的参数为Kp=1.5,T1=1,T=0.5,仿真结果出版社,2005:285-289如图3所示。2]席裕庚预测控制[M].北京:国防工业出版社,1993[3]周福恩,毕效辉.动态矩阵控制算法在过程控制中的应用研究[J].南通航运职业技术学院学报,2005,4(1)4345[4]何同祥,常宁青.动态矩阵控制算法在工业电加热炉温度控制中的应用[J.仪器仪表用户,2011,(01):28-3004[5}李玉红,刘红军,王东风,韩璞.一种新型的动态矩阵控制算法及仿真研究[J]计算机学报,2005,22(2):103-1091015公23[6]周忠海,张涛,陈哓高.基于动态矩阵控制算法的电加热炉图2DMC仿真纬果图图3传统Pm仿真结果图温度控制系统[J].山东科学,2005,18(5):7073我们知道传统的PID控制超调量过大,稳定时间长,控制7]触晓红,周佳精通GUI图形界面编程[M].北京:北京大学模型和参数需要比较精确,否则控制性能不会很好,而采用动出版社,2003作者简介:杨丽华(1987-),女,在读硕士研究生,主要从事预测控制方态矩阵控制算法则大大地抑制了超调量,消除了振荡,也缩短面的研究工作;赵文杰(1969-),男,华北电力大学控制科学与工程学了平衡时间,控制效果好。院副教授,主要从事热工过程的信息融合与先进控制方面的研究根据上述动态矩阵控制算法的基本流程及其操作编制成工作相应的m函数文件。这个设计包含动态矩阵控制算法优化功收稿日期2012041866EcVo.192012No,4欢迎光临本刊网站http://www.yqybyh.com
- 2020-12-02下载
- 积分:1