I. Overview This article refers to the address: http:// In recent years, with the application of electronic technology, computer technology and information technology, automotive electronic control technology has developed rapidly, especially in many aspects such as control accuracy, control range, intelligence and network. Automotive electronic control technology has become an important indicator of the development level of modern automobiles. The automotive electronic control system consists essentially of sensors, electronic controllers (ECUs), drives and control program software, and is used in conjunction with the mechanical system on the vehicle (usually integrated with the subsystems in the powertrain, undercarriage and body systems). And use cables or radio waves to transmit information to each other, so-called "electromechanical integration", such as electronic fuel injection system, anti-lock brake control system, anti-skid control system, electronic control suspension system, electronically controlled automatic transmission, electronic power steering Wait. The automotive electronic control system can be roughly divided into four parts: the engine electronic control system, the chassis integrated control system, the body electronic safety system, and the information communication system. Among them, the first two systems are directly related to the driving performance of the car. Second, the application of electronic control technology (1) Engine electronic control system The engine electronic control system (EECS) electronically controls the engine ignition, fuel injection, air to fuel ratio, exhaust gas, etc., so that the engine works under optimal conditions to improve its vehicle performance and save energy. Reduce the purpose of exhaust emissions. 1. Electronically controlled ignition device (ESA) The electronically controlled ignition device is composed of a microprocessor, a sensor, an interface thereof, an actuator, and the like. The device performs calculation and judgment according to the engine parameters measured by the sensor, and then adjusts the ignition timing, so that the engine can work under the optimal ignition advance angle under different conditions of different rotation speeds and intake air amount, so that the engine output is maximized. Power and torque, reducing fuel consumption and emissions, saving fuel and reducing air pollution. 2. Electronically controlled fuel injection (EFI) Controlled fuel injection devices have gradually replaced mechanical or electromechanical hybrid fuel injection systems due to their superior performance. When the engine is running, the device supplies the oil according to the parameters of the air flow, intake air temperature, engine speed and operating temperature measured by each sensor according to the pre-programmed program and the pre-stored optimal working condition in the memory. The control parameters are compared and judged, and the fuel supply amount is adjusted in time to ensure that the engine is always working in an optimal state, so that the overall performance of the engine is improved under the condition of outputting a certain power. 3. Exhaust gas recirculation control (EGR) Exhaust gas recirculation control systems are currently an effective measure to reduce nitrogen oxide emissions from exhaust gases. Its main actuator is a digitally controlled EGR valve that independently controls the amount of exhaust gas recirculated to the engine. The ECU adjusts the circulation rate of the recirculated exhaust gas according to the operating conditions of the engine in a timely manner. When the engine is running under load, the EGR valve is opened, and a part of the exhaust gas is introduced into the intake pipe and mixed with the new mixed gas, and then enters the cylinder combustion, thereby realizing recirculation. The exhaust gas sent to the intake system is optimally controlled to suppress the generation of harmful nitrogen oxides and reduce the amount of exhaust gas in the exhaust gas. However, excessive exhaust gas participation in the recirculation will affect the ignition performance of the mixture, thereby affecting the engine's power, especially in engine idle, low speed, small load and cold, the recirculated exhaust gas will significantly affect the engine performance. 4. Idle Speed ​​Control (ISC) The idle speed control system is implemented by adjusting the air passage area to control the intake air flow rate. The main actuator is the Idle Control Valve (ISC). The ECU compares the target rotational speed determined from the input signals of the respective sensors with the actual rotational speed of the engine, determines the control amount corresponding to the target rotational speed based on the difference obtained by the comparison, and drives the actuator that controls the air amount to make the idle speed Stay near the best. In addition to the above control devices, the engine part uses electronic technology: throttle timing, secondary air injection, engine boost, oil vapor evaporation, chamber volume, compression ratio, etc., and has been obtained on some models. The application. (2) Chassis integrated control system Chassis integrated control system includes electronically controlled automatic transmission, anti-lock braking system (ABS) and anti-skid system (ASR), electronic steering assist system (EPS), adaptive suspension system (ASS), cruise control system (CCS), etc. . 1. Electronically controlled automatic transmission (ECAT) In general, the speed and torque required by the car's drive wheels are significantly different from the speed and torque that the engine can provide. Therefore, the transmission system is required to change the gear ratio from the engine to the drive wheels. Power is transmitted to the drive wheels to accommodate the changing needs of external loads and road conditions. In addition, parking, reversing, etc. are also realized by the transmission system, timely coordinating the working conditions of the engine and the transmission system, fully utilizing the potential of the power transmission system to achieve the best matching, which is the fundamental task of the variable speed control system. ECAT can automatically change the position of the shift lever after calculation and judgment according to the engine load, speed, vehicle speed, brake working state and various parameters controlled by the driver, and accurately control the gear ratio according to the shift characteristics, thereby realizing the transmission. The best control of the shift, the best gear and the best shift time. The device has the advantages of high transmission efficiency, low fuel consumption, good shifting comfort, good running stability and long service life of the transmission. The use of electronic technology, especially microelectronics technology to control the shifting system, has become the main method for realizing automatic shifting functions in automobiles. 2. Anti-lock brake system (ABS) and drive anti-skid system (ASR) The anti-lock braking system of the car can sense the instantaneous movement state of the brake wheel, and ensure the optimal sliding rate of the wheel and the ground by controlling the wheel to prevent the car from being braked, so that the car can be made on various road surfaces. When moving, both the wheel and the ground can reach the longitudinal peak adhesion coefficient and the large lateral adhesion coefficient, so as to ensure that the vehicle does not have unsafe factors such as locking and towing, losing steering ability, etc. Maintaining directional stability and shortening the braking distance while moving, effectively improving the safety of driving. It is the most valuable application for automotive safety. The function and extension of the car anti-lock braking system is the drive anti-skid system (ASR), which has many common components. The system uses the speed sensor on the drive wheel to sense whether the drive wheel is slipping. When the slip occurs, the control element reduces the speed by braking or by the throttle to make it no longer slip. It is essentially a speed regulator that improves the longitudinal adhesion between the wheel and the road when the speed changes sharply in the starting and cornering, providing maximum driving force, improving its safety and maintaining the stability of the car. . 3. Electronic Steering Assistance System (EPS) The electronic steering assist system uses electric motor and electronic control technology to control the steering, and uses the power generated by the electric motor to assist the driver to perform power steering. The system does not directly consume the power of the engine. EPS is generally composed of a torque (steering) sensor, an electronic control unit, an electric motor, a speed reducer, a mechanical steering gear, and a battery power source. When the car is turning, the torque (steering) sensor will sense the torque of the steering wheel and the direction of the intended rotation. These signals will be sent to the electronic control unit through the data bus. The electronic control unit will according to the data such as the driving torque and the direction of the intended rotation. The motor controller sends an action command to the motor controller, and the motor outputs a corresponding magnitude of the rotational torque according to the specific needs, thereby generating a power steering. If you do not turn, the system will not work and is in the state to be called. The electronic steering assist system improves the steering and steering response characteristics of the car, increases maneuverability at low speeds, and adjusts stability during travel. At present, domestic medium and high-end car applications have more power steering. 4. Adaptive Suspension System (ASS) The adaptive suspension system can automatically and timely adjust the damping characteristics of the suspension and the stiffness of the suspension spring according to the instantaneous load of the suspension device to adapt to the instantaneous load and maintain the predetermined height of the suspension, which greatly improves the stability and operation of the vehicle. Sex and ride comfort. 5. Cruise Control System (CCS) Cruise Control, also known as the Constant Speed ​​Travel System, is a control system that allows the driver to travel at a fixed pre-selected speed without the need to operate the accelerator pedal. In long-distance driving, the patrol control system can be used, the driver does not have to frequently step on the throttle, and the constant speed running device will automatically adjust the throttle opening according to the driving resistance to adjust the vehicle speed near the constant speed state. In case of climbing, the speed of the vehicle has a downward trend, and the microcomputer control system automatically increases the throttle opening; when downhill, it automatically closes the small throttle opening to adjust the engine power to a certain speed. This control system is automatically disconnected when the driver changes gears or brakes. The system can alleviate the fatigue of the driver's long-distance driving, bring great convenience to the driving, and also get better fuel economy. (3) Body electronic safety system The body electronic safety system includes electronic equipment in the body system, mainly including adaptive headlight system, car night vision system, airbag, collision warning and prevention system, tire pressure monitoring system, automatic adjustment seat system, seat belt control system. Etc., improving the comfort and convenience of the driver and passengers. 1. Adaptive headlamp system (AFS) The adaptive headlamp system can calculate and judge the vehicle's current driving state and the headlight low beam according to the dynamic changes of the vehicle body and the operating characteristics of the steering mechanism within the headlight illumination range. The adjustment can automatically open and close and prevent glare when the car is in use. It can effectively reduce the fatigue of the driver's detour at night, so that the driver can see the actual road conditions at the turn, so that the driver can have sufficient time for steering and emergency situations, thus significantly improving the night bend. Driving safety. In Japan, some automakers have standard AFS systems in their premium cars. For example, Toyota Motor Corporation has adopted a variable headlight "adaptive headlamp system" on the hound. 2. Car night vision system (N VS) The night vision system is an all-weather electronic eye that extends the driver's range of vision to three to five times the range of the low beam illumination and helps the driver see the lights coming from afar, in the rain and snow, The objects on the highway in dense fog can also be seen, which greatly improves the safety of the car. The car night vision system works according to the infrared imaging principle and is a passive infrared imaging technology. The system itself does not emit any signals, but instead detects the heat of the object in front through a photographic sensor. The heat is concentrated into a detector that can pass various infrared wavelengths, and is detected by the infrared sensitive component of the detector (temperature-dependent The capacitor, whose capacitance varies with the amount of infrared received, is absorbed, and then the radiation is sequentially converted into an electrical signal and a digital signal, and the image is displayed to the driver through a front view (HUD) or an in-vehicle display. At present, more and more car manufacturers are beginning to develop and use car night vision systems, but due to price reasons, foreign major car manufacturers only use the system in their top luxury models, such as Hummer H2SUT, BMW Seven Series sedan, Mercedes-Benz new S-class sedan, Cadillac Diwei and so on. With the development of technology and the reduction of the production cost of night vision systems, car night vision systems will be fully popularized. 3. Airbag (SRS) This system is a common passive safety device on automobiles at home and abroad. When the vehicle collides, the galvanic material in the airbag is placed in the center of the steering wheel (some of which is also installed behind the instrument panel waste box) by the current control element, and rapidly burns to generate nitrogen gas, which instantly fills the airbag. The function of the airbag is to form a cushioning cushion between the driver and the steering wheel and between the front seat occupant and the instrument panel to avoid injury from hard impact. This device must be used in conjunction with the seat belt, otherwise the effect will be greatly reduced. 4. Collision Warning and Prevention System (CWAS) The system has various forms, some of which are in the car driving, when the distance between the two cars is small to a safe distance, it will automatically alarm. If you continue driving, it will automatically control the car brake to stop the car at the moment of collision. Some of them show the distance of obstacles behind the car when the car is reversing, effectively preventing the occurrence of a reverse accident. 5. Tire Pressure Monitoring System (TPWS) The level of inflation pressure in the car tire directly affects the comfort and safety of the vehicle. If the proper wheel pressure is maintained, the wear of the tire can be reduced, the fuel consumption can be reduced, the tire damage caused by the insufficient wheel pressure can be prevented, and the driving stability and safety of the automobile can be ensured. The tire pressure monitoring system automatically alerts the driver by continuously monitoring tire pressure, temperature and wheel speed. 6. Automatically adjust the seat system (AAS) The device is a combination of ergonomic technology and electronic control technology. It senses the posture of the occupant through the sensor and adapts the seat state to meet the passenger's comfort requirements. In addition to the above control systems, systems such as seat belt control systems, fatigue monitoring systems, automatic wiper systems, and intelligent rear view have also been applied to some models. (4) Information Communication System Information communication systems include car navigation and positioning systems, voice systems, information systems, and communication systems. 1. Car Navigation System and Positioning System (NTIS) The system can select the best driving route within the city or road network, and can display a map on the screen, indicating the position of the car while driving, and the direction and distance to reach the destination. This is essentially the direction in which the car is moving towards intelligent development, and further can become a driverless car. 2. Voice System (VS) The system includes two categories: voice alarm and voice control. Voice alarm is abnormal in the car, such as fuel temperature, coolant temperature, oil pressure, charging, taillights, headlights, exhaust temperature, brake fluid volume, hand brake, door is not closed, etc. When the phenomenon or the self-diagnosis system detects a fault, the computer outputs a message to the speaker or the alarm to make an alarm after logical judgment. Voice control is to use the driver's voice to command and control a certain part of the car, the device to operate. 3. Information System (IS) The system can process the engine's operating conditions and other information parameters through the microprocessor to output useful information to the driver. In addition to common contents such as coolant temperature, oil pressure, vehicle speed, and engine speed, the displayed information includes instantaneous fuel consumption, average fuel consumption, average vehicle speed, mileage, and outside temperature. According to the driver's needs, This information can be called up at any time. 4. Communication System (CS) The most used and most used in this area is the car phone, which is more popular in developed countries such as the United States, Japan, Europe, etc. The current level is constantly improving, except for the traffic between the car and the road, between the car and the car, and between the car and the airplane. In addition to the calls between the tools, satellites can be connected to the international telephone network to realize international telephone communication during driving, and realize network information exchange and image transmission. Nowadays, cars have access to wireless telephone networks, broadband digital signals, the Internet and other emerging wireless communication technologies, enabling people to access information and services anytime, anywhere. Third, the development trend of automotive electronic technology applications With the development of integrated control technology, computer technology and network technology, automotive electronic technology has clearly developed into three main directions of integration, intelligence and networking. (1) Integration In recent years, the maturity of embedded systems, LAN control and data bus technology has made the integration of automotive electronic control systems an inevitable trend in the development of automotive technology. Integrating the engine management system and the automatic transmission control system into the integrated control of the powertrain; combining the brake anti-lock control system, the traction control system and the drive anti-skid control system for braking control; through the central chassis controller, The control systems such as braking, suspension, steering and power transmission are connected through the bus. The controller coordinates the subsystems through complex control calculations to control the driving performance to the optimal level to form an integrated chassis control system. . (2) Intelligent The development of intelligent sensing technology and computer technology has accelerated the intelligent process of automobiles. The technical issues related to automotive intelligence have been highly valued by automakers. The concept of "autopilot" in its main technology will depend on electronic technology. The development of Intelligent Transportation Systems (ITS) will be combined with multiple interdisciplinary disciplines such as electronics and satellite positioning. It can provide the driver with the shortest distance and can bypass the relative density of vehicles according to the target data provided by the driver. Driving route. It is equipped with an electronic map that shows the road ahead and uses satellite navigation. From the global positioning satellites to obtain weather, traffic flow, traffic accidents, traffic jams and other conditions along the way, automatically screen out the best driving routes. (3) Networking With the increasing use of electronic control devices in automobiles, data communication between in-vehicle electronic devices is becoming more and more important. It is necessary to construct an automotive in-vehicle electronic network system based on a distributed control system. The rapid exchange of large amounts of data, high reliability and low cost are requirements for automotive electronic network systems. In this system, each sub-processor operates independently, controlling the performance of one aspect of the vehicle while providing data services while other processors are needed. The main processor collects and organizes the data of each sub-processor and generates a vehicle condition display. 72W Desktop Power Adapter,19V3.42A Desktop Power Adapter,15V4A Switching Power Supply Power Adapter,19V2.5A Wall Mounted Power Adapter Guangdong Mingxin Power Technologies Co.,Ltd. , https://www.mxpowersupply.com