外文翻譯--汽車交流底盤測功機測試系統(tǒng)研究

1、<p><b>　　附 錄</b></p><p>　　附錄A 外文資料翻譯</p><p>　　Study on the testing system of the auto AC chassis</p><p>　　Dynamometer</p><p>　　With the incessant pr

2、ogress of the science and technology, the automobileindustry of developes rapidly. The structure of automobile becomes perfect and the performance gets enhanced. On the one hand, the higher demand of automobile performan

3、ce accelerates the coalescent between traditional automobile technique and modern electron technology,and the automobile technical indexes have been enhanced greatly.On the other hand it accelerates the development of in

4、tegrated automobile detection technique</p><p>　　There are two methods for automobile performance test. One is the outdoor road test, the other one is the indoor frame test. The weather,condition of the road

5、 and the driving skills have great influence on the road test. However these factors have little influence on the results of indoor frame test. So the indoor frame test gets popular in the automobile test. Automobile cha

6、ssis dynamometer plays an important role in the automobile detection and diagnosis. Dynamic performance test can been done</p><p>　　Thus this thesis puts forward a new method with the help of an AC electric

7、dynamometer.The principle of AC electric dynamometer is similar as the asynchronous electromotor.With the rapid development of frequency converter,the AC electric dynamometer becomes more popular and easy to be controlle

8、d.The paper includes these main points as follows.</p><p>　　1. Simply introduce the principle and structure of the automobile chassis dynamometer.Adopts the anti-swing device for the driving wheel, and solve

9、s the swing of front-wheel drive cars. In order to recur the road resistance of the automobile,analyse the resistances of the car driving on the road and on the chassis dynamometer,draw a resistance equation separately a

10、bout the car.Then make contrast of the two equations,find their difference and put forward the electric simulation model.It provides </p><p><b>　　+ mg·sin+</b></p><p>　　The mode

11、l displays as follows.</p><p>　　2. Give the general technical demands.Analyse the principle of AC electric dynamometer.It has three running conditions according the difference of the slip.They are regenerati

12、on condition,electric drive condition and electromagnetic brake condition.For this reason the AC electric dynamometer is proper to be used in chassis dynamometer and can satisfy the demand.Use the advanced AC variable fr

13、equency technique to control the dynamometer.This system adopts the direct torque control of frequency co</p><p>　　3. After choosing the proper sensors for the system, design the part of data collection and

14、analysis,and analyse the amplification of analog signals in detail.In order to do the electric simulation the speed and acceleration are necessary.The system uses an improved method to measure the speed, and uses least s

15、quare method to get the acceleration.It has excellent precision at low speed and high speed.Analyse the interferential factors,and adopt proper measures to restrain the disturb and assure </p><p>　　4. The te

16、sting system is based on Windows XP and program with VC++6.0. The testing system can operate alone and can operate online. The software of the system adopts blocking design according to the system design demand.That is t

17、o say,if any one logic part of the software was changed,it wouldn’t affect other parts.And any module can be transferred by other modules.The testing interface is friendly.Take the acceleration test and sliding performan

18、ce test for example, introduce their testing proces</p><p>　　5. Analyse the reason of the error, demarcate the speed sensor and force sensor to see the quality of the linearity of the sensors.The results sho

19、w the two sensors have good linearity and satisfy GB/T18276-2000 ‘Test method and evaluation index for the automobile dynamic frame benches’.Use a truck do the acceleration test from 30km/h to 90km/h on the road and on t

20、he chassis dynamometer separately,then make contrast of the results and show that the electric simulation model is correct basically.</p><p>　　The automobile chassis dynamometer itself is very complicated.Th

21、e thesis can’t describe every aspect in detail.And it is hard to avoid some mistakes and disadvantages.The testing system needs to been further researched and improved,and needs doing more experiments to validate its fea

22、sibility</p><p>　　汽車交流底盤測功機測試系統(tǒng)研究</p><p>　　隨著科學技術的不斷進步，汽車工業(yè)得到了迅猛的發(fā)展。汽車結構不斷完善，汽車性能不斷提高。人們對汽車性能要求的不斷提高，一方面促進了傳統(tǒng)的汽車技術與現(xiàn)代電子技術的結合，使汽車的經(jīng)濟技術指標在最近幾十年有了大幅度的提高；另一方面，它促進汽車綜合性能現(xiàn)代檢測技術的發(fā)展和廣泛應用，大大提高了汽車新產品的開發(fā)速度

23、和出廠產品質量的控制能力。</p><p>　　汽車性能測試分為室外道路試驗測試和室內臺架測試，由于道路試驗受氣候、道路條件狀況及駕駛技術等因素的影響比較大，汽車檢測以室內臺架測試為主。汽車底盤測功機是一項重要的汽車檢測設備，在汽車檢測行業(yè)扮演著十分重要的角色。利用底盤測功機，我們不僅可以對汽車進行動力性能檢測，在配備油耗儀和尾氣分析儀的基礎上，我們還可以在不同工況下對汽車的燃油經(jīng)濟性和尾氣排放進行測試分析。目前

24、的底盤測功機主要以電渦流測功機和水力測功機為主，通常配備一些慣性飛輪來對汽車的慣性阻力進行相應模擬。通過控制電磁離合器的吸合與斷開來控制不同飛輪的組合，以實現(xiàn)對不同質量汽車運動慣量的模擬。但有限數(shù)量的飛輪，不能實現(xiàn)汽車慣量的無級模擬，不能滿足當前各種類型汽車的檢測需求，而且模擬精度有待提高。</p><p>　　由此本文提出了采用交流測功機模擬汽車行駛阻力。這樣不僅省去了繁瑣的慣性飛輪，簡化了機械結構，而且可實現(xiàn)

25、慣量的無級模擬。本文從總體上進行系統(tǒng)設計與分析，主要包括以下幾點。</p><p>　　1．對汽車底盤測功機的原理和結構進行簡單介紹，采用課題組自行開發(fā)的汽車車輪防偏擺機構，有效解決了前輪驅動型汽車在測功機上運行時的橫擺問題，并保證了測試時的安全性。為了在底盤測功機上真實再現(xiàn)汽車道路行駛工況，需要真實反映汽車的道路行駛阻力。文章分別對汽車在道路上和底盤測功機上的運行狀況進行了力學分析，建立了交流測功機電模擬的數(shù)學

26、模型。</p><p><b>　　+ mg·sin+</b></p><p>　　該數(shù)學模型為進一步交流測功機的電模擬提供了理論依據(jù)。</p><p>　　2．對系統(tǒng)提出總體技術要求，分析交流測功機的工作原理，在轉差率不同的情況下，交流測功機分別運行于發(fā)電測功狀態(tài)，拖動狀態(tài)以及電磁制動狀態(tài)。由于交流測功機既可以運行于發(fā)電測功狀態(tài)，又

27、可以運行于拖動狀態(tài)，適合用于底盤測功機中。利用目前先進的變頻調速技術來控制測功機。系統(tǒng)采用變頻器中的直接轉矩控制技術，通過計算機控制變頻器可實現(xiàn)底盤測功機的恒轉速控制、恒轉矩控制及道路模擬方式控制。</p><p>　　3．對系統(tǒng)采用的傳感器做出合理選型之后，進而對數(shù)據(jù)的采集和處理進行了分析，并就如何對模擬信號進行放大做了具體分析。采用合理的數(shù)據(jù)采集卡將數(shù)據(jù)輸入計算機。由于電模擬需要測得速度和加速度，針對本文選用

28、的光電編碼器，本文采用了一種新的測試速度和加速度的方法，測試精度有所提高。分析系統(tǒng)干擾產生的機理，并就干擾問題采取了相應的措施進行抑制。</p><p>　　4．本測試系統(tǒng)以 Windows XP 為平臺，采用 VC++6.0 進行編程。系統(tǒng)既可以單機運行，也能適應檢測線聯(lián)網(wǎng)檢測的要求。系統(tǒng)的軟件部分根據(jù)系統(tǒng)的設計要求，程序采用模塊化，即程序中某一程序段內的任何邏輯部分都可以任意更改而不影響程序的其它部分，每一模

29、塊程序都可以作為一個子程序供其它程序調用。測試系統(tǒng)界面友好，以加速性能測試和滑行性能測試為例進行了介紹，并給出整個測試系統(tǒng)的軟件流程圖。</p><p>　　5．對誤差的產生做簡單介紹之后，對系統(tǒng)中的速度傳感器和拉壓力傳感器進行了相關標定工作。通過標定試驗，表明傳感器線性度良好，測量精度滿足 GB/T 18276-2000《汽車動力性臺架試驗方法和評價指標》中對底盤測功機測試精度的要求。以汽車在道路上和底盤測功機