【正文】 steering system and hydraulic steering system, in motor or hydraulic system problems, still can take the human to control the car [9]. The system of micro controller if malfunction, because no mechanical system is connected the steering wheel and steering gear, so it could not control cars to turn around. for wire control power steering system outlook Although wire control power steering system now not satisfactory, but SBW still clear is car development direction. SBW system eliminates mechanical connection between the design of steering wheel, tyre will be greatly simplified. Not only improve the design efficiency, but also improve the economy, and car improve overall safety. SBW system work mainly by the electronic ponents to assume. The application of electronic ponents marks a considerable amount of mechanical parts reductions, and steering system the size and weight of ease. The whole process of steering by electronic device to achieve, which greatly improved vehicle fuel efficiency. Because only in need to, we have energy consumption. Based on instantaneous driver condition, the control unit of data from receiving other systems, actuator force needed only supply tires. Steering performance improvement is dependent on sensor receives speed, traction control system and other related variables. When the accident happened to the driver, the most dangerous is the steering wheel collisions. In the car with SBW system, many injuries and deaths due to the steering wheel can be eliminated. Due to the elimination of the mechanical connection, so to high reliability is absolutely necessary. In Europe, have related standards, such as IEC 61508 and EN 61511 [10]. Pure electronic system cannot guarantee failure conditional probability of less than 10 times failure/hour. Because of this and designed the system structure of the fault tolerance, and accurate processing strategy method is necessary. In the control strategies to avoid the failure data errors, and from, active detection, self diagnosis and protection will be used to achieve safety and reliability [11]. For the foreseeable SWB system design and analysis of tolerance, it will bee one of the important before SWB popular topic. 譯文前言近年來(lái)，隨著社會(huì)生活的汽車化，汽車的保有量不斷增加，由此造成交通情況錯(cuò)綜復(fù)雜，使得駕駛員轉(zhuǎn)向盤的操作頻率增大，這就需要減輕駕駛疲勞，提高操縱的輕便性和靈活性，因此對(duì)動(dòng)力轉(zhuǎn)向系統(tǒng)的要求也越來(lái)越高。t work. Electric power steering system can realtime in different speed for car turned to provide different under the instrumentality of guarantee in lowspeed driving car deft and agile, high speed is stable and reliable. Electric power steering system generally consists of mechanical parts and controlling part. Mechanical parts mainly include transmission unit (the clutch, the steering assembly) and execution unit (electrical), etc. Control part mainly according to sensors to speed and torque signal for puting, drive motor control instructions issued to provide power for steering. EPS pared with HPS, except to save energy outside, due to the elimination of the hydraulic system and improve the environmental performance, solves the malpractices of hydraulic drive brings. The system is made of manufacturers to provide to the vehicle manufacturer, can be directly mounted. Under different conditions of different models, and different for different drivers steering properties, through software modification, convenient and quick. Complete EPS system also includes fault diagnosis and safety protection system. When malfunction happened, could stop booster, automatic recovery to manually control mode and warning signal, and show the memory of abnormal content such as torque sensor itself anomalies, and motor speed sensor abnormal work abnormal, battery abnormal etc [5]. Electric power steering system has bee the vehicle steering system technology development, but the system of mainstream has its limitations, because motor power steering and provide power is limited, if the body is heavier, steering system needs to have larger drive power, electric power steering system is ragged. So the system more for small cars, has lots of equipment to senior cars, and gradually to regular cars and small mercial vehicle development. wire control power steering system With power Steering technology development, the Wire control power Steering system (Steering By Wire, abbreviation SBW) is as automobile electronic technology development and grows the latest achievements of a brandnew Steering system. It through the wire transfer signals, control actuator action to replace traditional steering system of mechanical transmission and mechanical connection from the main controller, help torque in corresponding parameters, after decoding to turn his orders, by executive motor steering motor provides. SBW cancelled and steering wheel steering plate between mechanical connection device, now the steering wheel module, steering executive module and the main controller ECU, three main parts and automatic protection fault systems, power auxiliary module. It is made up of a realtime bus structure (for example, FlexRay HTTP or CAN) connected to the equipment [6]. Can easily and other system integration, unified coordination control. System work, sensor test driver39。隨著未來(lái)汽車市場(chǎng)的快速發(fā)展和汽車電子價(jià)值含量的迅速提高，我國(guó)汽車電動(dòng)轉(zhuǎn)向系統(tǒng)將形成巨大經(jīng)濟(jì)規(guī)模效應(yīng)。（3）轉(zhuǎn)向輪具有自動(dòng)回正能力。②密封襯墊等經(jīng)過(guò)拆卸后應(yīng)更換新件。 動(dòng)力轉(zhuǎn)向系的修理以寶來(lái)乘用車為例： 拆卸①拆下萬(wàn)向節(jié)，將萬(wàn)向節(jié)從轉(zhuǎn)向器中拉出。 測(cè)量轉(zhuǎn)向盤上的轉(zhuǎn)向力超過(guò)40N應(yīng)予以檢查維修，同時(shí)，轉(zhuǎn)向盤自由行程應(yīng)在規(guī)定范圍內(nèi)。②檢查油液是否有起泡或乳化現(xiàn)象。將轉(zhuǎn)向直拉桿的兩個(gè)球頭銷分別裝到轉(zhuǎn)向搖臂和轉(zhuǎn)向節(jié)上臂錐孔內(nèi)，按規(guī)定力矩?cái)Q緊球頭銷螺母，裝好開口銷。④球頭銷螺紋應(yīng)無(wú)損傷，否則應(yīng)更換；球頭銷彈簧不應(yīng)有彈力減弱或折斷現(xiàn)象，否則應(yīng)更換。（3）緊固和潤(rùn)滑。m。前后移動(dòng)轉(zhuǎn)向齒條約15次，使齒條處于穩(wěn)定狀態(tài)，然后繼續(xù)擰緊壓簧調(diào)整螺塞，③裝配轉(zhuǎn)向小齒輪。用專用工具拆下軸上彈性擋圈，再用專用工具拆卸軸承。③拆卸防塵套鎖簧和防塵罩管箍，拆下轉(zhuǎn)向器齒條防塵罩。（6）潤(rùn)滑。（2）檢查轉(zhuǎn)向器外殼是否破裂，視情況焊補(bǔ)或更換?？潭缺P通過(guò)磁力座吸附在駕駛室儀表盤或轉(zhuǎn)向管柱上，指針則固定在轉(zhuǎn)向盤的周緣上；也可將指針通過(guò)磁力座固定在儀表板或轉(zhuǎn)向管柱上，而刻度盤固定在轉(zhuǎn)向盤周緣上。轉(zhuǎn)向力的檢測(cè)可按轉(zhuǎn)向輕便性實(shí)驗(yàn)方法進(jìn)行，一般有原地轉(zhuǎn)向力實(shí)驗(yàn)、低速大轉(zhuǎn)角（“8”字行駛）轉(zhuǎn)向力實(shí)驗(yàn)、彎道轉(zhuǎn)向力實(shí)驗(yàn)等，可參照有關(guān)國(guó)家標(biāo)準(zhǔn)的規(guī)定進(jìn)行檢測(cè)。如果轉(zhuǎn)向太輕，又可能導(dǎo)致駕駛員路感太弱或汽車“發(fā)飄”，同樣不利于行車安全。）、轉(zhuǎn)向盤外緣最大轉(zhuǎn)向切向力（即轉(zhuǎn)向盤最大轉(zhuǎn)向力，N）、轉(zhuǎn)向輪最大轉(zhuǎn)向角（176。 故障診斷方法轉(zhuǎn)向時(shí)發(fā)出“咔噠”聲，在已排除轉(zhuǎn)向泵葉片噪聲的情況下，則由轉(zhuǎn)向泵帶輪出現(xiàn)松動(dòng)引起。詳見(jiàn)圖23所示動(dòng)力轉(zhuǎn)向系轉(zhuǎn)向沉重助力部分常見(jiàn)故障原因的診斷流程。②油路堵塞或不暢，應(yīng)予檢修。