资源描述
附 录 A 外文文献Overview ofDevelopment on Vehicle EPS SystemAbstractThe currentdevelopment of an electric power steering(EPS) system in an automobile is explicated. The structure, types and characteristics of electric power steering system are introduced. The modeling technologies for electric power steering system and control strategies are analyzed and compared. The development trend of electric power steering system in an automobile is also discussed. It is pointed that the electric power steering technology is one orientation ofpower steering technologies in the future, and whichwill occupy a predominantposition in power steering field.Key words:Automobile; Electric power steering system; Development trend1 EPS system types and characteristics1.1 EPS system classificationThe early development of EPS system is low in steering type car。Present 4 types of EPS system are based on rack-and pinion steering system,The installation position according to power motors can be divided into different:Type booster steering、Small gear power type、Double small gear power type and Rack power type。The steering the instrumentality of motor power type EPS installed in the steering,Motor power torque through increased after worm worm gear deceleration in the steering directly added twist。Its advantage is motor can be installed in any position hacking,Relative to other several types minimum cost;The drawback to motor torque ripple effects of driver feel bigger。 The drawback to motor torque ripple effects of driver feel bigger,The instrumentality of torque motor added in small gear axle directly。Advantage: rigid, steering road to feel strong。Double pinion steering rack boosts type EPS are installed on two small gear, A small gear and steering plate connected, power motors through another pinion and rack meshing, provide power for rack. Advantage: can provide relatively large pow.1.2 EPS system meritEPS system and the traditional hydraulic power steering system has the following advantages compared（1)EPS in various riding condition can provides the best efforts。In the car or parking at Treasury and low-speed steering provide enough power for the driver，In high-speed steering made drivers have good road feeling，And reduce caused by pavement of rough disturbance of steering system，Improving auto steering characteristics。（2）Improve the car fuel economy，Urban conditions can improve fuel economy. (3) the average 5%, saving fuel 3. EPS system only when the vehicle steering only provide power, Unlike traditional hydraulic power steering system even in dont turn,Pumps have been running.（3）EPS system structure is compact, parts, convenient in installation and smaller number to assemble, enhanced the labor productivity due to tell the packed in engine pulleys and oil pump, set aside of the space can be used to install other parts of FIAT Punto production company adopted DELPHI company developed the electric power steering system, loading time reduced around 80 percent.（4）EPS system cancelled hydraulic loop, there is no oil leakage and oil leakage problem, reduce the pollution to the environment, and save a lot of steering oil.（5）EPS system has the function of self diagnosis, convenient in maintenance and maintenance.（6） EPS system has good low temperature performance, even in 40 environment, EPS system also can work very well, has higher reliability and safety.（7） EPS systems biggest advantage is the performance of the whole system can not changing the system structure of the cases, by changing the system control strategy of programming realize, in order to meet different models and different driving feel the need, greatly reduced the development cost and improve the efficiency of development.2 EPS System Key ComponentsEPS system key components Angle sensor are mainly torque sensor speed preach2.1 Corner Sorque SensorSensors for real-time detection of steering Angle rotation direction and steering disk disk position，The torque sensor for real-time detection steering dish torque size，And will signal transmission to EPS system of electronic control unit (ECU)。Corner the torque sensor precision problem decided the electric power steering system performance and reliability，Accelerate development research performance reliable, low-cost corner torque sensor is very important，The cost of the sensor is restricted by the electric power steering system one of the main factors market.2.2 Speed SensorThe wheel speed sensors used to measure the size of the average speed speed sensor using electromagnetic induction sensor installation on the sensor in gearbox according to the change, the main speed pulse vice two system signals to ECU, because this was two system, therefore the signal reliability improved2.3 Power MotorsPower motors is EPS system actuators, and help motor characteristics directly affect the EPS system to control the ease or drivers handle EPS system for power motors are basic requirements of the high reliability should be, big power, low noise and vibration, low friction torque, small volume and weight; Can turn in blocking next output torque; good mechanical properties, in the process of operation, as far as possible to small torque ripple; The small inertia should as far as possible; Should be able to fast reverse current EPS system the instrumentality of permanent magnet dc motor are usually motive brushless dc motor and switched reluctance motor dc have brush motor mature technology, controller, low cost, but simple existing wear easily power dense brush Spark, need not often maintenance and high efficiency and power density under。Therefore, suitable for the development of the EPS systems used low cost high power density of brushless dc motor is the future research direction of electric motor booster.2.4 Reducing GearIts and motor is linked together, up slow increase twist of the deceleration agencies role EPS system often adopted worm and worm wheel mechanism circulating ball screw nut planetary gear agencies to ensure that EPS system only in a predetermined speed range role, some EPS system also with clutch when speed up to a certain value, clutch, motor stopped working, steering system.2.5 Electric Power Steering Electronic control unit (ECU) function is based on steering Angle torque and speed of the disk, logical analysis and signal, issue commands to calculate, control the action in addition, boosts motor has a safety protection and self ECU diagnose function ECU through gather current generator voltage engine conditions signal judge its system working condition is normal, once.3 EPS System Research Situation3. 1 EPS System Development SituationEPS system was first by Japanese suzuki motor company in 1988 February development, Cervo small cars in the equipment installed in the Alto, then in 1993, Honda motor company is the worlds first put EPS as standard equipment configuration in advanced sports car AcuraNSX, Japan automobile manufacturers then the Mira and mitsubishis wrath Minica correspondingly installed EPS system since then, electric power to turn Booster motor,The two companies are about 70% models adopted the steering power type EPS starting and GM chose TRW company offers of a transitional technology, including electric hydraulic steering technology,Volkswagen is in its PQ35 was used on the platform of the complex ZF provide double small gear power type EPS.In a foreign country, EPS system application range is from original mini on commercial to limousines MPV, booster forms from low speed range booster type to full speed range booster type direction.At present domestic to EPS system research, mainly on the hacking power type with mini car carry EPS system on EPS of university basically has: study of tsinghua university, Beijing university of science and technology, huazhong university of science and technology university in Beijing university of tianjin university of hefei technical university of jiangsu automobile industry of hubei province, wuhan university of technology, college guangzhou Honda flying across SiDi, changhe plough is the earliest equipment models, EPS EPS system makes these cars became the highlight of participates in the market competition.4 ConclusionEPS systems involve the sensor technology microelectronics control modern control theory and the traditional mechanical design, EPS to represent the future car power steering technology development direction, will serve as a standard accessories one of the bus, and equipment in power steering field is the dominant so EPS is very wide application prospect, our country is necessary to increase investment on research and development.
展开阅读全文