What is electronic throttle?

1, the concept Introduction

the inner member in a motor vehicle, the fuel supply amount control apparatus is referred to as an internal combustion engine throttle. Its role is to manipulate the flow throttle opening degree control of the combustible mixture, speed and power of the engine changes, in order to accommodate the needs of cars. Traditional engine throttle actuating means is operated by a cable (soft steel), or rod, one end of coupling an accelerator pedal (accelerator pedal), and the other end coupled to the throttle interlocking plate. However, this conventional throttle application areas are limited and the lack of precision in the ever-changing automotive electronics technology developments, an electronic throttle (EGAS) came into being.
is through electronic throttle position sensor, an accelerator depression depth and transmission speed of the signal, thereby realizing functions of the electronic throttle control device. This signal can be received on-board computer and interpret, and then send control commands to the throttle in accordance with instructions that it should be open or mitigate opening angle. This process is accurate and fast. There is no problem of mechanical wear.

2, structures

Electronic throttle control system consists of an accelerator pedal, a pedal displacement sensor, the ECU (electronic control unit), a data bus, the servo motor and the throttle valve actuator components.
In the displacement sensor is mounted inside the accelerator pedal position of the accelerator pedal can be closely monitored. When detecting the height position of the accelerator pedal changes, this information will be instantly sent to ECU, ECU performs arithmetic processing on the data and information coming from other systems, calculates a control signal through the line to the servo motor relay, the servo motor drives the throttle actuator, the data bus system is responsible for communication between ECU and other ECU. As electronic throttle system is to adjust the throttle by ECU, therefore electronic throttle system can set various functions to improve safety and driving comfort. In the current engine electronic fuel injection, electronic throttle can be further improved fuel economy and emissions performance of the engine, because it controls the power of the engine regulating door.

3, the working principle

by a conventional accelerator wire cable end and the other end is connected to the accelerator pedal and the throttle valve connected to its transmission ratio is 1: 1, that is to say with the foot how much, how much is the throttle opening angle, but in many cases, the throttle valve should not open such a large angle, so in this case the throttle valve opening angle is not necessarily the most scientific, although very direct but this way its control accuracy is poor. And electronic throttle opening of the throttle is controlled by a cable or harness, and automatic control function.
When the driver depresses the accelerator required throttle pedal position sensor signal will be sensed by the to pass cables ECU, ECU through the analysis, determination, and issues an instruction to the drive motor, and is driven by a motor controlled throttle valve the opening degree to adjust the flow rate of the combustible mixture, when the large load, large throttle openings, into the combustible mixture within the cylinder multiple, if using the throttle cable can only rely on the depth of the foot pedal to control the throttle opening of the throttle degrees, the opening angle of the throttle valve is difficult to achieve the theoretical air-fuel ratio is adjusted to a state, and the electronic throttle ECU through various data collected by the sensor analysis, comparison, and command the operation of the throttle actuator, the section transferred to the best position of the valve, and in order to achieve different load conditions can be close to 14.7: 1 stoichiometric air-fuel state, to fully burn the fuel. Encounter some novice or inexperienced drivers in daily driver due to improper operation, or a little too aggressive driver, suddenly stepped on the accelerator pedal will be the case in the end, this operation is not scientific, is not conducive to fuel economy and the engine will bring harm. Suddenly opened the throttle, and this was the maximum load state of the engine at full load will cause incomplete combustion engine, but will also increase the injector fuel injection, resulting in a waste of fuel, the engine load increases, reducing the use of engine life is not conducive to environmental protection. Wire throttle vehicles, ECU is not possible to throttle control, can only default to the mistake, most will be slightly adjusted in terms of the injection, but still can not solve the fundamental problem. As for the electronic throttle is all downhill. Then ECU would think that at this time the driver is a non-DivisionDriving school practice, so will command the throttle open a certain speed, rather than the speed of synchronization with the driver depresses the pedal. To do so except to protect the engine, improve fuel economy than, but also allows the driver to feel very smooth feel, improved occupant comfort.
may be understood, the vehicle electronic throttle accelerator pedal is “false throttle”, but a receiver, after receiving the driver stepped on the accelerator operation, the operation will be the strength and amplitude data to the control unit analysis, and the driver stepped on the accelerator summarizes intent, and then calculating by the control unit according to the actual opening degree command a throttle control a throttle motor operation.

4, the function

function of the electronic throttle control system is mainly embodied in two parts: ASR (traction control system) system and a speed control (cruise control). Traction control

When the ASR system is sensed rotational speed of the wheel, the ECU according to the difference between the position of the accelerator pedal, steering wheel angle and wheel speed determined slip ratio and the like, by reducing the throttle opening degree adjust the mixture flow, in order to reduce the engine power control purposes. In the ASR system, the electronic throttle play a crucial role in the ASR system which involves the entire vehicle speed control, idle control and other functions, the system can quickly and accurately execute instructions. I.e., when the electronic throttle system ASR system receives the instruction, it is only the throttle control command from the ASR, thus avoiding erroneous motorists. Speed ​​Control

When the motorist speed control system, the vehicle speed sensor signal input ECU, and then controlling the throttle opening degree of the servo motor output command from the ECU. In such a system, according to a change in the running resistance automatically adjust the engine throttle opening by the control system, the travel speed remained stable. Therefore, the electronic throttle system can be compatible with the cruise control function.
In the current engine electronic fuel injection, electronic throttle addition to their above-described functions, it can further improve fuel economy and emissions performance of the engine, because it controls the power of the engine regulating door. Therefore, the electronic throttle can play a role are many.

5, the technical characteristics

Compared with the conventional accelerator, an electron accelerator obvious feature can harness (wire) cable or rod in place, put in a side of the throttle valve micromotor , motor driven throttle opening degree. The so-called “wire driving”, with a wire to replace the original mechanical transmission. On the surface it is to replace the traditional cable throttle cable but substantially not simply change the connection mode, but can automatically control the power output of the entire vehicle. Advantage

First, the electronic throttle can be determined according to the intention of the driver’s range of motion of the throttle details, in order to achieve a precise control.
Second, the ratio of fuel-efficient accelerator cable, more smoothly.
Third, high stability, easy to break, and flame moving. Drawback

First, the working principle of complexity, high cost, the cost of a corresponding increase.
Second, there is a delay effect, not as good as a conventional reaction accelerator cable quickly.
Third, the structure is relatively complicated, there is a problem of failure rate.
In general, an electronic throttle controls the access to the ECU, to become part of the all-electric vehicle, cruise control and other modules can be mounted, conform to the trend of the overall automotive technology.

6, technology

In order to change the delay defects electronic throttle, the accelerator electronic throttle emerged, brings the following changes:
advantages
First, the throttle signal amplification, improve static response
electronic throttle accelerator so-called “accelerated” sensitivity is achieved primarily, amplifies the input throttle signal will increase by 50 percentage throttle response. This means that, at any time, 33 percent throttle pedal rearmost signal has been useless, the driver depresses the pedal 66When the accelerator percentage is already full throttle the output, so that the sensitivity of throttle response increased by 50 percentage. However, the electronic throttle accelerator does not like a lot of people say reducing the throttle signal classification, in fact, the throttle signal is still stepless adjustment, but from the previous 1: 1 is adjusted 1: 1.x, x is the signal amplification factor.
Second, the amplified signal throttle growth, enhance the dynamic response
when the accelerator pedal is depressed, the accelerator will calculate the rate of change of the accelerator depression signal according to the magnitude, the time, the faster the change, indicating more intense acceleration request, throttle accelerator will increase this rate of change, the effect is ultimately better dynamic response speed.
Third, the provision of false driving style for the ecu to adjust engine parameters
ecu modern engines generally have a driving style adaptive capacity, if the driver is often rapid deep pedal (commonly known as pull speed), ecu will gradually think of the driver trend style “intense”, this will gradually adjust the engine throttle valve, the injection system or the like to obtain optimal adjustment of the parameters of the engine in this style. After using electronic throttle accelerator, even if driving under the previous “moderate” driving style, the engine will still get “intense” driving experience, which is equivalent to deceive the ecu, the passage of time, the engine will automatically modify its parameters to suit the style . After
shortcomings
installed electronic throttle accelerator, may lead to too sensitive throttle, the car is not good control, maneuverability will decrease the fuel consumption will definitely increase.