阅读说明：本技术 一种发动机控制策略及发动机控制系统 (Engine control strategy and engine control system ) 是由 仇杰 王祝 徐佳 李勇 于 2018-05-29 设计创作，主要内容包括：本发明公开一种发动机控制策略及发动机控制系统,该发动机控制策略,当当前的发动机实际转速变化率大于预设的第一阈值并且当前的发动机进气压力变化率大于预设的第二阈值时,提高发动机目标转速并使发动机获得补偿扭矩。该发动机控制策略通过提高发动机目标转速,增加发动机的扭矩输出能力,并通过向发动机提供补偿扭矩,抵消整车附加给发动机的负载,由此改善了手动变速车辆的离合器结合性能,使起步和换挡过程平稳顺畅。并且,该发动机控制策略通过发动机实际转速变化率和发动机进气压力变化率来识别提高发动机目标转速和向发动机提供补偿扭矩的时机,使手动变速车辆无需安装离合器行程传感器即可实施该发动机控制策略。(The invention discloses an engine control strategy and an engine control system. The engine control strategy increases the torque output capacity of the engine by increasing the target rotating speed of the engine, and counteracts the load of the whole vehicle added to the engine by providing compensation torque to the engine, so that the clutch combination performance of the manual speed change vehicle is improved, and the starting and gear shifting processes are smooth and stable. The engine control strategy identifies the timing for increasing the target engine speed and providing the engine with compensating torque through the actual engine speed change rate and the engine intake pressure change rate, so that the manual transmission vehicle can implement the engine control strategy without installing a clutch stroke sensor.)

1. An engine control strategy for improving clutch engagement performance of a manually-variable transmission vehicle is characterized in that when a current actual engine speed change rate is greater than a preset first threshold and a current engine intake pressure change rate is greater than a preset second threshold, an engine target speed is increased and a compensation torque is obtained for the engine.

2. The engine control strategy according to claim 1, characterized in that an intermediate compensation torque is calculated in real time according to the engine speed change rate, the difference between the engine target speed and the engine actual speed, and the intermediate compensation torque is the compensation torque required by the engine.

3. the engine control strategy of claim 1, wherein the intermediate compensation torque is calculated in real time based on a rate of change of engine speed, a difference between a target engine speed and an actual engine speed; calculating a correction value in real time according to the change rate of the air inlet pressure of the engine and the gear of the manual transmission; the correction value multiplied by the intermediate compensation torque is the compensation torque that the engine needs to obtain.

4. The engine control strategy according to any one of claims 1-3, characterized in that when the current actual engine speed is greater than the sum of the current target engine speed and the preset third threshold, the target engine speed is no longer increased and the engine is no longer allowed to obtain the compensation torque.

5. The engine control strategy according to any of claims 1-3, characterized in that when the clutch is fully released, the target engine speed is no longer increased and the engine is no longer allowed to achieve the compensation torque.

6. An engine control system implementing the engine control strategy according to any one of claims 1-5, characterized in that the engine control system comprises an engine controller, an engine actual rotational speed sensor (11) and an engine intake pressure sensor (112); the engine controller comprises a first module (131), the first module (131) being in communication with the engine actual speed sensor (11) and the engine intake pressure sensor (112) for calculating an engine actual speed rate of change and an engine intake pressure rate of change;

The engine controller further comprises a second module (132), the second module (132) being preset with a first threshold and a second threshold; the second module (132) increases the target engine speed and causes the engine to achieve the compensation torque when the rate of change of the actual engine speed is greater than the first threshold and the rate of change of the engine intake pressure is greater than the second threshold.

7. The engine control system of claim 6, characterized in that the second module (132) is pre-programmed with: a first corresponding relation among the engine speed change rate, the difference between the engine target speed and the engine actual speed and the intermediate compensation torque; the first corresponding relation is a two-dimensional map which takes the engine speed change rate, the difference between the target engine speed and the actual engine speed as input quantities and the intermediate compensation torque as output quantities.

8. The engine control system of claim 7, further comprising a gear sensor (14) in communication with the second module (132); the second module (132) is also pre-programmed with: a second corresponding relation among the change rate of the air inlet pressure of the engine, the gear of the manual transmission and the correction value; the second corresponding relation is a two-dimensional map which takes the change rate of the air inlet pressure of the engine and the gear of the manual transmission as input quantities and takes the corrected value as an output quantity; the correction value multiplied by the intermediate compensation torque is the compensation torque that the engine needs to obtain.

9. The engine control system of any of claims 6-8, characterized in that the second module (132) is preset with a third threshold; when the current actual engine speed is greater than the current target engine speed plus a predetermined third threshold, the second module (132) no longer increases the target engine speed and no longer causes the engine to achieve the compensation torque.

10. An engine control system as claimed in any one of claims 6 to 8, characterized in that the engine control system further comprises a clutch top switch (15); the clutch top position switch (15) is used for sending a trigger signal to the second module (132) when the clutch is completely released, and the second module (132) does not increase the target rotating speed of the engine any more and does not enable the engine to obtain compensation torque any more after receiving the trigger signal.

Technical Field

The invention relates to the technical field of engines, in particular to an engine control strategy and an engine control system, which are used for improving the combination performance of a manual transmission.

background

When the vehicle starts and shifts gears, a driver needs to firstly step on a clutch pedal, separate the clutch to enable an engine and a transmission system to be disengaged, then put the transmission into a corresponding gear, and then gradually release the clutch pedal to enable the clutch to be gradually combined.

During clutch engagement, the engine load increases, causing the actual engine speed to drop or have a tendency to drop. In order to avoid stalling the vehicle when starting or engaging the gear, the driver is required to gradually release the clutch and simultaneously depress the accelerator pedal to increase the fuel supply to the engine so that the actual engine speed is substantially maintained at a steady engine speed.

the timing of depression of the accelerator pedal should be substantially coincident with the clutch engagement point. The clutch engagement point is a half-link time when the clutch starts to engage with the drive train but is not fully engaged with the drive train. If the clutch is released soon and then the accelerator pedal is stepped on, vehicle jerk can occur, which affects the driving and riding experience.

Disclosure of Invention

In order to solve the technical problem, the invention provides an engine control strategy, when the current actual rotating speed change rate of the engine is greater than a preset first threshold value and the current engine intake pressure change rate is greater than a preset second threshold value, the target rotating speed of the engine is increased, and the engine obtains compensation torque.

When the clutch is at the joint point in the starting and gear shifting process of the manually-changed vehicle, the whole vehicle is added with a certain load to the engine, so that the actual rotating speed of the engine is reduced. Therefore, the actual rotating speed of the engine is basically kept at the stable rotating speed in the starting and gear shifting processes of the manual variable speed vehicle, so that the combination performance of the clutch is improved, and the starting and gear shifting processes are stable and smooth.

Furthermore, the engine control strategy provided by the present invention identifies the timing at which the target engine speed needs to be increased and compensation torque needs to be provided to the engine by the actual engine speed rate of change and the engine intake pressure rate of change, i.e., identifies the clutch engagement point by the actual engine speed rate of change and the engine intake pressure rate of change. According to the arrangement, the engine control strategy can be implemented without installing a clutch stroke sensor, so that the engine control strategy is easier to popularize and implement.

Optionally, an intermediate compensation torque is obtained by real-time calculation according to the engine speed change rate and the difference between the target engine speed and the actual engine speed, and the intermediate compensation torque is the compensation torque required to be obtained by the engine.

Optionally, calculating an intermediate compensation torque in real time according to the engine speed change rate and the difference between the target engine speed and the actual engine speed; calculating a correction value in real time according to the change rate of the air inlet pressure of the engine and the gear of the manual transmission; the correction value multiplied by the intermediate compensation torque is the compensation torque that the engine needs to obtain.

Alternatively, when the current actual engine speed is greater than the sum of the current target engine speed and the preset third threshold, the target engine speed is not increased and the engine does not obtain the compensation torque.

Alternatively, when the clutch is fully released, the target engine speed is no longer increased and the engine is no longer allowed to achieve the compensation torque.

The invention also provides an engine control system, which comprises an engine controller, an actual engine rotating speed sensor and an engine air inlet pressure sensor; the engine controller includes a first module in communication with the engine actual speed sensor and the engine intake pressure sensor for calculating an engine actual speed rate of change and an engine intake pressure rate of change;

The engine controller also comprises a second module, wherein the second module is preset with a first threshold value and a second threshold value; the second module increases the target engine speed and causes the engine to achieve the compensation torque when the rate of change of the actual engine speed is greater than the first threshold and the rate of change of the engine intake pressure is greater than the second threshold.

Optionally, the second module is preset with: a first corresponding relation among the engine speed change rate, the difference between the engine target speed and the engine actual speed and the intermediate compensation torque; the first corresponding relation is a two-dimensional map which takes the engine speed change rate, the difference between the target engine speed and the actual engine speed as input quantities and the intermediate compensation torque as output quantities.

Optionally, the engine control system further comprises a gear sensor in communication with the second module; the second module also presets: a second corresponding relation among the change rate of the air inlet pressure of the engine, the gear of the manual transmission and the correction value; the second corresponding relation is a two-dimensional map which takes the change rate of the air inlet pressure of the engine and the gear of the manual transmission as input quantities and takes the corrected value as an output quantity; the correction value multiplied by the intermediate compensation torque is the compensation torque that the engine needs to obtain.

Optionally, a third threshold is preset in the second module; when the current actual engine speed is greater than the sum of the current target engine speed and a preset third threshold, the second module does not increase the target engine speed any more and does not enable the engine to obtain the compensation torque any more.

Optionally, the engine control system further comprises a clutch top position switch; the clutch top position switch is used for sending a trigger signal to the second module when the clutch is completely released, so that the second module does not increase the target rotating speed of the engine any more after receiving the trigger signal and does not make the engine obtain the compensation torque any more.

The engine control system provided by the invention has the advantages basically consistent with the beneficial effects of the engine control strategy, and is not repeated here.

Drawings

FIG. 1 is a schematic control flow diagram of one embodiment of an engine control strategy provided by the present invention;

FIG. 2 is a control flow diagram of one embodiment of an engine control system provided by the present invention.

Wherein the reference numerals in fig. 2 are explained as follows:

01 engine, 11 actual engine speed sensor, 12 engine intake pressure sensor, 131 first module, 132 second module, 14 gear sensor, 15 clutch top position switch.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1, fig. 1 is a schematic control flow diagram of an embodiment of an engine control strategy provided by the present invention.

As shown in fig. 1, the present invention provides an engine control strategy, when the current actual engine speed change rate is greater than a preset first threshold and the engine intake pressure change rate is greater than a preset second threshold, the target engine speed is increased and the engine 01 obtains a compensation torque.

When the clutch is at the joint point in the starting and gear shifting process of the manually-changed vehicle, the whole vehicle is added with a certain load to the engine 01, so that the actual rotating speed of the engine is reduced, and at the moment, the engine control strategy provided by the invention increases the torque output capacity of the engine 01 by improving the target rotating speed of the engine, and offsets the load added to the engine 01 by the whole vehicle by providing compensation torque to the engine 01. Therefore, the actual rotating speed of the engine is basically kept at the stable rotating speed in the starting and gear shifting processes of the manual variable speed vehicle, so that the combination performance of the clutch is improved, and the starting and gear shifting processes are stable and smooth.

Furthermore, the engine control strategy provided by the present invention identifies the timing of the need to increase the engine target speed and the need to provide a compensation torque to the engine 01 by the actual engine speed rate of change and the engine intake pressure rate of change. In fact, the timing needed to increase the engine target speed and to provide torque compensation to the engine 01 is when the clutch is at the clutch engagement point. Therefore, in other words, the invention provides an engine control system which identifies the clutch engagement point through the actual engine speed change rate and the engine intake pressure change rate. According to the arrangement, the engine control strategy can be implemented without installing a clutch stroke sensor, so that the engine control strategy is easier to popularize and implement.

The above compensation torque can be obtained in two ways:

The first way is to calculate an intermediate compensation torque in real time according to the engine speed change rate and the difference between the target engine speed and the actual engine speed, and use the intermediate compensation torque as the compensation torque required by the engine.

The second mode is that the intermediate compensation torque is calculated in real time according to the change rate of the engine rotating speed, the difference between the target rotating speed of the engine and the actual rotating speed of the engine, and the correction value is calculated in real time according to the change rate of the air inlet pressure of the engine and the gear position of the manual transmission; and taking the product of the correction value and the intermediate compensation torque as the compensation torque required by the engine.

Further, as shown in fig. 1, the engine control strategy provided by the present invention does not increase the engine target speed and does not make the engine 01 obtain the compensation torque any more when the current actual engine speed is greater than the sum of the current engine target speed and the preset third threshold.

further, as shown in FIG. 1, the present invention provides an engine control strategy that, when the clutch is fully disengaged, no further increases the engine target speed and no further compensation torque is achieved for the engine 01.

That is, when either of the two conditions, i.e., the "current actual engine speed is greater than the sum of the current target engine speed and the third threshold value" or the "clutch is completely released" is satisfied, the target engine speed is no longer increased and the engine 01 is no longer allowed to obtain the compensation torque.

Referring to fig. 2, fig. 2 is a control flow diagram of an embodiment of an engine control system according to the present invention.

As shown in fig. 2, the engine control system provided by the present invention includes an engine actual rotational speed sensor 11 for detecting an actual rotational speed of the engine, an engine intake pressure sensor 12 for detecting an engine intake pressure, and an engine controller.

The engine controller includes a first module 131, and the first module 131 communicates with the engine actual speed sensor 11 and the engine intake pressure sensor 12 to obtain an engine actual speed and an engine intake pressure, and calculates an engine actual speed change rate and an engine intake pressure change rate based thereon.

Also, the engine controller includes a second module 132. The second module 132 is preset with the first threshold for identifying the actual rate of change of engine speed and the second threshold for identifying the rate of change of engine intake pressure. The second module 132 determines whether the actual engine speed change rate obtained by the first module 131 is greater than a first threshold and whether the engine intake pressure change rate obtained by the first module 131 is greater than a second threshold, and increases the target engine speed and makes the engine 01 obtain the compensation torque when both are satisfied.

the second module 132 may be said to be in speed-torque control mode when the second module 132 increases the target engine speed and causes the engine 01 to achieve the compensation torque.

Specifically, to realize the first compensation torque obtaining manner, the second module 132 is preset with: the first correspondence between the rate of change of the engine speed, the difference between the target engine speed and the actual engine speed, and the intermediate compensation torque allows the second module 132 to determine the intermediate compensation torque based on the current rate of change of the actual engine speed, the current target engine speed, and the current difference between the actual engine speed.

The first corresponding relation may be a two-dimensional map obtained by experimental calibration, in which the two are input quantities, i.e., the actual engine speed change rate, the difference between the target engine speed and the actual engine speed, and the intermediate compensation torque is output quantity.

Specifically, to implement the second compensation torque obtaining manner, the engine control system further includes a gear sensor 14, where the gear sensor 14 is in communication with the second module 132, so that the second module 132 obtains a current gear of the manual transmission.

The second module 132 is preset with: the second corresponding relationship among the engine intake pressure change rate, the manual transmission gear and the correction value enables the second module 132 to calculate the correction value in real time according to the current engine intake pressure change rate and the current gear pair of the manual transmission.

The second corresponding relation may be a two-dimensional map obtained through experimental calibration, in which the engine intake pressure change rate and the gear in which the manual transmission is located are used as input quantities, and the correction value is used as an output quantity.

Further, the second module 132 is preset with a third threshold identifying the difference between the actual engine speed and the target engine speed. The second module 132 determines whether the actual engine speed is greater than the sum of the current target engine speed and the third threshold, and if so, the second module 132 no longer increases the target engine speed and no longer causes the engine 01 to achieve the compensation torque, i.e., the second module 132 exits the speed-torque control mode.

Further, the engine control system provided by the invention also comprises a clutch top position switch 15. The clutch top switch 15 is triggered when the clutch is fully released, and the clutch top switch 15 sends a trigger signal to the second module 132. The second module 132 receives the trigger signal and does not increase the target engine speed and does not cause the engine 01 to achieve the compensation torque, i.e., the second module 132 exits the speed-torque control mode.

That is, the second module 132 exits the speed-torque control mode when either of the two conditions is met, i.e., "the current actual engine speed is greater than the current target engine speed plus the third threshold" or "the clutch is fully disengaged".

The engine control system and the engine control strategy provided by the invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.