CN110103944B

CN110103944B - Engine starting method, device and equipment

Info

Publication number: CN110103944B
Application number: CN201910312908.9A
Authority: CN
Inventors: 杨培林; 王晓娟; 刘一光; 吴士朋; 梁清华; 张昆
Original assignee: Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Automobile Research and Development Co Ltd
Current assignee: Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Automobile Research and Development Co Ltd
Priority date: 2019-04-18
Filing date: 2019-04-18
Publication date: 2021-01-19
Anticipated expiration: 2039-04-18
Also published as: CN110103944A

Abstract

The invention relates to an engine starting method, device and equipment, comprising the steps of obtaining a clutch gear when the engine is determined to be started through a clutch; judging whether the engine needs to be started through delayed oil injection according to the clutch gear; if the engine needs to be started through delayed oil injection, whether a first starting condition of the engine is met is judged according to the torque of the clutch and the rotating speed of the engine; starting the engine if the clutch torque and the engine speed satisfy the first starting condition; and if the clutch torque and the engine speed do not reach the first starting condition, returning to the step of judging whether the first starting condition of the engine is met or not according to the clutch torque and the engine speed. According to the invention, when the clutch is started, the oil injection time of the engine can be flexibly judged according to the starting condition of the clutch, so that the early oil injection is avoided; and simultaneously, for three starting modes of starting of the 12V starter, clutch starting and ISG starting, the engine respectively controls the fuel injection amount during starting.

Description

Engine starting method, device and equipment

Technical Field

The invention relates to the technical field of engine starting systems, in particular to an engine starting method, device and equipment.

Background

Along with the exhaustion of traditional energy, novel energy is generally applied, and especially in the automobile industry, many big automobile manufacturers choose hybrid to replace traditional fuel oil system, and skill fuel saving reduces the consumption of the energy, can guarantee the duration of a motor vehicle again.

Existing hybrid systems may be powered by an internal combustion engine as the primary propulsion device and an electric motor as the secondary propulsion device. Single motor hybrid schemes can be divided into five broad categories, designated P0, P1, P2, P3 and P4, respectively, depending on the location of the motor relative to the conventional power system.

Common hybrid power systems are P2 and P3, but when a motor in the P2 system drives a vehicle, electric energy cannot be recovered at the same time, and a bottleneck exists in efficiency; the motor in the P3 system must be connected with the axle, so the motor cannot be used for starting the engine, and the motor cannot be integrated with the gearbox or the engine, and the extra volume is occupied. Therefore, a P2.5 system is developed, which can combine the advantages of the P2 system and the P3 system and avoid the disadvantages of the P2 system and the P3 system.

There are three ways to start the engine of a P2.5 hybrid vehicle: 12V starter start, electric machine (ISG) start, and clutch start. Wherein the 12V starter is started, i.e. the starting mode of the conventional vehicle, is used with lower priority on the hybrid vehicle. The ISG starting and the clutch starting are two newly added starting modes of the P2.5 hybrid vehicle: the ISG start is usually used for starting the engine when the vehicle speed is 0 or very low (<10kph), the ISG output torque, the clutch 2 are combined, and the engine is reversely dragged to start; the clutch start is usually used for engine start at low (>10kph), medium and high vehicle speeds, the clutch 1 or the clutch 2 is combined (depending on the starting gear) to reversely drag the engine start through the vehicle running inertia, meanwhile, the ISG outputs torque to the wheel end for compensation, and the clutch start is divided into different start modes (mainly according to the speed of the clutch torque output), such as quick start, safe start, smooth start and the like, so as to meet different working conditions during start.

In the processes of starting the engine by the ISG and starting the engine by the clutch, namely, in the process of switching the vehicle from pure electric to hybrid electric, the starting problems such as impact, shaking and the like are easy to occur, and particularly, the problem of unsmooth starting of the clutch is more obvious when the vehicle speed is low. There are two reasons related to engine start phase control: one is that after the clutch starts the engine, the time when the engine starts oil injection and combustion is too early, and the combustion torque of the engine and the torque of the clutch interfere with each other; the other reason is that the control logic of the fuel injection amount in the starting stage of the engine does not distinguish between clutch starting and ISG starting, the fuel injection amount of 12V starting is adopted, the dragging speed is low (200-300 rpm) during 12V starting, a large fuel injection amount is needed, the engine can rapidly exceed the starting target speed from the low dragging speed, the dragging speed of ISG starting and clutch starting is high, and the fuel injection amount needed in the starting stage of the engine is small.

In order to solve the problems, an engine starting method, an engine starting device and engine starting equipment need to be developed in a P2.5 system, so that the oil injection time of an engine can be flexibly judged according to the starting condition of a clutch when the clutch is started, and early oil injection is avoided; and simultaneously, for three starting modes of starting of the 12V starter, clutch starting and ISG starting, the engine respectively controls the fuel injection amount during starting.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide an engine starting method, device and equipment, which introduce delay oil injection to ensure that the oil injection time of an engine is flexibly judged when a clutch is started to start, so that early oil injection is avoided; and simultaneously, under three starting modes of 12V starter starting, clutch starting and ISG starting, the oil injection amount is respectively controlled, and the cost is reduced.

In order to solve the above problem, the present invention provides an engine starting method including:

when the engine is determined to be started through the clutch, acquiring a current clutch gear;

judging whether the engine needs to be started through delayed oil injection according to the clutch gear;

if the engine needs to be started through delayed oil injection, judging whether a first starting condition of the engine is met according to the current clutch torque and the current engine speed of the vehicle;

starting the engine if the clutch torque and the engine speed satisfy the first starting condition;

and if the clutch torque and the engine speed do not reach the first starting condition, returning to the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle.

Further, the method further comprises:

if the engine does not need to be started through the delayed oil injection, judging whether the current engine speed of the vehicle reaches a second starting condition of the engine or not;

starting the engine if the engine speed reaches the second starting condition;

and if the engine speed does not reach the second starting condition, returning to the step of judging whether the current engine speed of the vehicle reaches the second starting condition of the engine.

Further, before acquiring the current clutch gear, the method further includes:

calculating the fuel injection quantity for starting the engine;

when an engine starting request is received, acquiring the current speed of a vehicle;

judging whether the vehicle speed meets zero or not according to the vehicle speed;

and if the vehicle speed meets the zero vehicle speed, calculating and determining the fuel injection quantity of the motor for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode.

Further, the judging whether the vehicle speed meets the zero vehicle speed according to the vehicle speed further comprises:

if the vehicle speed does not meet the zero vehicle speed, judging whether the vehicle speed is less than a preset vehicle speed or not according to the vehicle speed;

and if the vehicle speed is less than the preset vehicle speed, calculating and determining the fuel injection quantity of the 12V starter for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode.

And if the vehicle speed is not less than the preset vehicle speed, calculating and determining the fuel injection quantity of the clutch for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode.

Further, the clutch gear determining whether the engine needs to be started by the delayed fuel injection includes:

judging whether the clutch gear reaches a preset gear point or not;

if the clutch gear reaches the gear position point, starting the engine through delayed oil injection is not needed;

if the clutch gear does not reach the gear position, the engine needs to be started by delaying fuel injection.

Further, the first start-up condition includes:

determining a preset torque target value, a preset engine speed target value and a preset engine speed target difference value;

calculating the current engine speed difference according to the rotating speed and the target value of the engine speed

Judging whether the torque of the clutch is larger than the torque target value or not according to the torque of the clutch;

the first launch condition is not met if the clutch torque is greater than the torque target value.

Further, if the clutch torque is not larger than the torque target value, judging whether the clutch torque is larger than the engine speed target difference or not according to the engine speed difference;

if the engine speed difference is greater than the engine speed target difference, the first start condition is not met;

and if the engine speed difference is not greater than the engine speed target difference, the first starting condition is met.

Further, the second starting condition includes:

determining a preset target value of the engine speed;

judging whether the rotating speed is greater than the target engine rotating speed value or not according to the rotating speed;

if the rotating speed is greater than the target engine rotating speed value, the second starting condition is met;

if the rotational speed is not greater than the engine rotational speed target value, the second start condition is not satisfied.

In another aspect of the present invention, an engine starting apparatus is further provided, including:

a clutch gear acquisition unit for acquiring a current clutch gear when it is determined that the engine is started by the clutch;

the first judgment unit is used for judging whether the engine needs to be started through delayed oil injection according to the clutch gear;

the second judgment unit is used for judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine rotating speed of the vehicle when the engine needs to be started through delayed oil injection;

the first execution unit is used for starting the engine when the clutch torque and the engine speed meet the first starting condition;

and the second execution unit is used for returning to execute the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle when the clutch torque and the engine speed do not reach the first starting condition.

In another aspect of the present invention, an engine starting apparatus is also protected, including: the system comprises an information acquisition device, a clutch controller, a motor controller, a 12V starter controller and an engine controller;

the clutch controller is used for acquiring a current clutch gear when the engine is determined to be started through the clutch;

the clutch controller is used for judging whether the engine needs to be started through delayed oil injection according to the clutch gear;

the clutch controller and the engine controller are used for judging whether a first starting condition of the engine is reached or not according to the current clutch torque and the current engine speed of the vehicle when the engine needs to be started through delayed oil injection;

the clutch controller and the engine controller are used for starting the engine when the clutch torque and the engine speed meet the first starting condition;

and the clutch controller and the engine controller are used for returning to execute the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle when the clutch torque and the engine speed do not reach the first starting condition.

Due to the technical scheme, the invention has the following beneficial effects:

1) according to the engine starting method, the engine starting device and the engine starting equipment, delay oil injection is adopted, the oil injection time of the engine can be flexibly judged under the condition that the engine is started by the clutch, and the phenomena of interference, impact, jitter and the like caused by the fact that the torque of the engine and the torque of the clutch are interfered due to too early oil injection time are avoided.

2) According to the engine starting method, the engine starting device and the engine starting equipment, for three starting modes of starting of the 12V starter, clutch starting and ISG starting, the engine respectively controls the fuel injection quantity during starting, so that the phenomena of constant fuel injection quantity, impact, jitter and the like in various starting modes are avoided, fuel can be saved, and cost is reduced.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings used in the description of the embodiment or the prior art will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a flow chart of a method for starting an engine requiring a late injection according to an embodiment of the present invention;

FIG. 2 is a method for starting an engine without delaying injection of fuel according to an embodiment of the present invention;

FIG. 3 is a flow chart illustrating fuel injection to start the engine according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of an engine starting apparatus according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a clutch gear acquiring unit provided by the embodiment of the invention;

fig. 6 is a schematic structural diagram of a first determining unit according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a second determining unit according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a third determining unit according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic may be included in at least one implementation of the invention. In the description of the present invention, it is to be understood that the terms "upper", "lower", "left", "right", "top", "bottom", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Moreover, the terms "first," "second," and the like are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein.

Example one

The first embodiment provides a vehicle gear shifting method, as shown in fig. 1, including:

s101, when the engine is determined to be started through the clutch, the current clutch gear is obtained.

Specifically, before the current clutch gear is obtained, the method further includes: calculating an injection quantity for starting the engine, the injection quantity comprising:

s301, when an engine starting request is received, acquiring the current speed of a vehicle;

s302, judging whether the vehicle speed meets zero or not according to the vehicle speed;

and if the vehicle speed meets the zero vehicle speed, calculating and determining the fuel injection quantity of the engine started by the motor according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode.

s303, if the vehicle speed does not meet the zero vehicle speed, judging whether the vehicle speed is smaller than a preset vehicle speed or not according to the vehicle speed;

Further, the preset vehicle speed is 10 Kph.

S102, judging whether the engine needs to be started through delayed oil injection according to the clutch gear.

Further, whether the gear of the clutch reaches a preset gear point is judged;

S103, if the engine needs to be started through delayed oil injection, judging whether a first starting condition of the engine is achieved according to the current clutch torque and the current engine speed of the vehicle.

Specifically, the first starting condition includes:

calculating the current engine speed difference value according to the rotating speed and the target engine speed value;

if the clutch torque is greater than the torque target value, the first launch condition is not met;

if the clutch torque is not greater than the torque target value, judging whether the clutch torque is greater than the engine rotating speed target difference value or not according to the engine rotating speed difference value;

Further, the torque target value is-3 Nm.

Further, the target engine speed difference is 50 rpm.

Specifically, as shown in fig. 2, the method further includes:

s201, acquiring the current engine speed of the vehicle;

s202, when the engine does not need to be started through delayed oil injection, judging whether the rotating speed reaches a second starting condition of the engine or not;

starting the engine if the engine speed reaches the second starting condition;

Specifically, the second starting condition includes:

determining a preset target value of the engine speed;

Further, the target engine speed is 900 rpm.

The embodiment provides an engine starting method, which introduces delay oil injection to ensure that the oil injection time of an engine is flexibly judged when a clutch is started, so as to avoid early oil injection; and simultaneously, under three starting modes of 12V starter starting, clutch starting and ISG starting, the oil injection amount is respectively controlled, and the cost is reduced.

Example two

The second embodiment provides an engine starting apparatus, as shown in fig. 4, including:

a clutch gear acquisition unit 400 for acquiring a current clutch gear when it is determined that the engine is started by the clutch;

the first judgment unit 500 is used for judging whether the engine needs to be started through delayed oil injection according to the clutch gear;

a second judging unit 600, configured to judge whether a first starting condition of the engine is met according to a current clutch torque and a current engine speed of a vehicle when the engine needs to be started through delayed fuel injection;

a first executing unit 700 for starting the engine when the clutch torque and the engine speed satisfy the first starting condition;

and a second executing unit 800, configured to, if the clutch torque and the engine speed do not meet the first starting condition, return to executing the step of determining whether the first starting condition of the engine is met according to the current clutch torque and the current engine speed of the vehicle.

Specifically, the apparatus further comprises:

a third judging unit 900 for judging whether the current engine speed of the vehicle reaches the second starting condition of the engine after determining that the engine does not need to be started by the delayed oil injection;

a third executing unit 1000 that starts the engine if the engine speed reaches the second starting condition;

and the fourth execution unit 1100, if the engine speed does not reach the second starting condition, returns to execute the step of judging whether the current engine speed of the vehicle reaches the second starting condition of the engine.

Specifically, as shown in fig. 5, the clutch gear obtaining unit 400 includes:

a vehicle speed obtaining module 401, configured to obtain a current vehicle speed of the vehicle when receiving an engine start request

A fourth judging module 402, configured to judge whether a zero vehicle speed is met according to the vehicle speed;

a fifth judging module 403, configured to judge whether the vehicle speed is less than a preset vehicle speed according to the vehicle speed;

and the fuel injection quantity determining module 404 calculates and determines the fuel injection quantity of at least one starter of the motor, the 12V starter and the clutch for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode.

Specifically, as shown in fig. 6, the first judging unit 500 includes:

a sixth determining module 501, configured to determine whether the clutch gear reaches a preset gear point;

a fifth execution module 502 for not requiring engine start by late fuel injection if the clutch gear reaches the gear position;

a sixth execution module 503 is configured to start the engine with a delayed fuel injection if the clutch gear does not reach the gear position.

Specifically, as shown in fig. 7, the second judgment unit 600 includes:

a target value determination module 601 for determining a preset torque target value, a preset engine speed target value and a preset engine speed target difference;

an engine speed difference determination module 602, configured to calculate a current engine speed difference according to the rotational speed and the engine speed target value;

a seventh determining module 603, configured to determine whether the clutch torque is greater than the torque target value according to the clutch torque;

a seventh execution module 604 for failing to meet the first start condition when the clutch torque is greater than the torque target value or the engine speed difference is greater than the engine speed target difference;

an eighth determining module 605, configured to determine whether the engine speed difference is greater than the target engine speed difference according to the engine speed difference;

an eighth executing module 606, configured to meet the first starting condition when the engine speed difference is not greater than the engine speed target difference.

Specifically, as shown in fig. 8, the third judging unit 900 includes:

a ninth determining module 901, configured to determine whether the engine speed is greater than the target engine speed according to the rotation speed;

a ninth executing module 902, configured to meet the second starting condition when the rotation speed is greater than the target engine rotation speed;

a tenth execution module 903 is configured to, when the rotation speed is not greater than the engine rotation speed target value, not satisfy the second starting condition.

Specifically, before the current clutch gear is obtained, the fuel injection amount for starting the engine is calculated: when an engine starting request is received, the vehicle speed obtaining module 401 obtains the current vehicle speed of the vehicle; the fourth judging module 402 judges whether the vehicle speed meets zero vehicle speed according to the vehicle speed, and if the vehicle speed meets zero vehicle speed, the fuel injection quantity determining module 404 calculates and determines the fuel injection quantity of the motor for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode; if the vehicle speed does not meet the zero vehicle speed, the fifth judging module 403 judges whether the vehicle speed is less than a preset vehicle speed according to the vehicle speed; if the vehicle speed is less than the preset vehicle speed, the fuel injection quantity determining module 404 calculates and determines the fuel injection quantity of the 12V starter for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode; if the vehicle speed is not less than the preset vehicle speed, the fuel injection amount determination module 404 calculates and determines the fuel injection amount of the clutch to start the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode.

Specifically, when it is determined that the engine is started by the clutch, the clutch gear acquisition unit 400 acquires the current clutch gear; the first determination unit 500 determines whether the engine needs to be started by the delayed oil injection according to the clutch gear.

Further, the sixth determining module 501 determines whether the clutch gear reaches a preset gear point; the fifth execution module 502 does not require starting the engine with a late fuel injection if the clutch gear reaches the gear position; if the clutch gear does not reach the gear position, the sixth execution module 503 may require starting the engine via a late fuel injection.

Specifically, if it is required to start the engine by the delayed fuel injection, the second determination unit 600 determines whether the first start condition of the engine is reached according to the current clutch torque and the current engine speed of the vehicle; if the clutch torque and the engine speed satisfy the first start condition, the first execution unit 700 starts the engine; if the clutch torque and the engine speed do not reach the first starting condition, the second executing unit 800 returns to execute the step of determining whether the first starting condition of the engine is satisfied according to the current clutch torque and the current engine speed of the vehicle.

Further, the first start-up condition includes: the target value determination module 601 determines preset torque target values, engine speed target values and engine speed target difference values; the engine speed difference determination module 602 calculates a current engine speed difference based on the speed and the engine speed target value; the seventh determining module 603 determines whether the clutch torque is greater than the torque target value; the seventh execution module 604 fails the first launch condition if the clutch torque is greater than the torque target value; if the clutch torque is not greater than the torque target value, the eighth determining module 605 determines whether the engine speed difference is greater than the engine speed target difference according to the engine speed difference; if the engine speed difference is greater than the engine speed target difference, the seventh execution module 604 fails to meet the first start condition; the eighth execution module 606 satisfies the first enablement condition if the engine speed difference is not greater than the engine speed target difference.

Specifically, when it is not necessary to start the engine by the delayed oil injection, the third determination unit 900 determines whether the current engine speed of the vehicle reaches the second start condition of the engine; if the engine speed reaches the second starting condition, the third execution unit 1000 starts the engine; if the engine speed does not reach the second starting condition, the fourth execution unit 1100 returns to execute the step of determining whether the current engine speed of the vehicle reaches the second starting condition of the engine.

Further, the ninth determining module 901 determines whether the engine speed is greater than the target engine speed according to the rotation speed; when the speed is greater than the target engine speed, the ninth execution module 902 meets the second start condition; when the speed is not greater than the engine speed target, the tenth execution module 903 does not satisfy the second start condition.

The second embodiment provides an engine starting device, which introduces delayed oil injection to ensure that the oil injection time of the engine is flexibly determined when the clutch is started, so that premature oil injection is avoided; and simultaneously, under three starting modes of 12V starter starting, clutch starting and ISG starting, the oil injection amount is respectively controlled, and the cost is reduced.

EXAMPLE III

The third embodiment provides an engine starting apparatus, comprising: the system comprises an information acquisition device, a clutch controller, a motor controller, a 12V starter controller and an engine controller;

the clutch controller and the engine controller are used for returning to execute the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle when the clutch torque and the engine speed do not reach the first starting condition

Further, the 12V starting controller is used for calculating and determining the oil injection amount of the 12V starter for starting the engine according to the current water temperature of the water tank, the ambient pressure and the oil injection mode.

Further, the motor controller is used for calculating and determining the oil injection amount of the engine started by the motor according to the current water temperature of the water tank, the ambient pressure and the oil injection mode.

And further, the clutch controller is used for calculating and determining the oil injection amount of the engine started by the clutch according to the current water temperature of the water tank, the ambient pressure and the oil injection mode.

Specifically, the engine starting apparatus is equipped with the above engine starting device, and starts the engine by the above engine starting method.

The third embodiment provides an engine starting device, which introduces delayed oil injection to ensure that the oil injection time of the engine is flexibly determined when the clutch is started, so that premature oil injection is avoided; and simultaneously, under three starting modes of 12V starter starting, clutch starting and ISG starting, the oil injection amount is respectively controlled, and the cost is reduced.

It should be noted that, for the sake of simplicity, the foregoing method embodiments are described as two series of acts, but those skilled in the art should understand that the present invention is not limited by the described order of acts, as some steps may be performed in other orders or simultaneously according to the present invention. Similarly, the modules in the engine start control apparatus are referred to as computer programs or program segments for performing one or more specific functions, and the distinction between the modules does not mean that the actual program code is necessarily separated. Further, the above embodiments may be arbitrarily combined to obtain other embodiments.

In the foregoing embodiments, the descriptions of the embodiments have respective emphasis, and reference may be made to related descriptions of other embodiments for parts that are not described in detail in a certain embodiment. Those of skill would further appreciate that the various illustrative logical blocks, units, and steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, elements, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design requirements of the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present embodiments.

The foregoing description has disclosed fully preferred embodiments of the present invention. It should be noted that those skilled in the art can make modifications to the embodiments of the present invention without departing from the scope of the appended claims. Accordingly, the scope of the appended claims is not to be limited to the specific embodiments described above.

Claims

1. An engine starting method for starting an engine of a P2.5 system, the P2.5 system comprising: 12V starter motor, motor and clutch characterized by, includes:

when the engine is started through the clutch, acquiring a current clutch gear, wherein the starting of the engine through the clutch refers to the combination of the clutch in the running process of the vehicle, and dragging the engine to start through the running inertia of the vehicle;

if the clutch torque and the engine speed do not reach the first starting condition, returning to execute the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle;

wherein the first start-up condition comprises:

calculating the current engine speed difference according to the engine speed and the target engine speed value;

2. An engine starting method as set forth in claim 1, further comprising:

starting the engine if the engine speed reaches the second starting condition;

3. An engine starting method as set forth in claim 1, wherein said obtaining a current clutch gear further comprises:

calculating the fuel injection quantity for starting the engine;

4. An engine starting method as set forth in claim 3 wherein said determining whether zero vehicle speed is met based on said vehicle speed further comprises:

if the vehicle speed is less than the preset vehicle speed, calculating and determining the fuel injection quantity of the 12V starter for starting the engine according to the current water temperature of the water tank, the ambient pressure and the fuel injection mode;

5. The engine starting method of claim 1, wherein said clutch gear determining whether starting the engine by delayed fuel injection is required comprises:

judging whether the clutch gear reaches a preset gear point or not;

6. An engine starting method as set forth in claim 1, wherein if said clutch torque is not greater than said torque target value, determining whether or not it is greater than said engine speed target difference value based on said engine speed difference value;

7. An engine starting method as set forth in claim 2, characterized in that the second starting condition includes:

determining a preset target value of the engine speed;

judging whether the engine speed is greater than the target engine speed value or not according to the engine speed;

if the engine speed is greater than the engine speed target value, the second starting condition is met;

the second start condition is not satisfied if the engine speed is not greater than the engine speed target value.

8. An engine starting apparatus for starting an engine of a P2.5 system, the P2.5 system comprising: 12V starter motor, motor and clutch characterized by, includes:

the clutch gear acquiring unit is used for acquiring a current clutch gear when the engine is determined to be started through a clutch, wherein the engine is started through the clutch, namely the clutch is combined in the running process of the vehicle, and the engine is dragged to be started through the running inertia of the vehicle;

and the second execution unit is used for returning to execute the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle if the clutch torque and the engine speed do not reach the first starting condition, wherein the first starting condition comprises the following steps:

9. An engine starting apparatus for starting an engine of a P2.5 system, characterized by comprising: the system comprises an information acquisition device, a clutch controller, a motor controller, a 12V starter controller and an engine controller;

the clutch controller is used for acquiring a current clutch gear when the engine is determined to be started through the clutch, wherein the engine is started through the clutch, namely the clutch is combined in the running process of the vehicle, and the engine is dragged to be started through the running inertia of the vehicle;

the clutch controller and the engine controller are used for returning to the step of judging whether the first starting condition of the engine is met or not according to the current clutch torque and the current engine speed of the vehicle when the clutch torque and the engine speed do not reach the first starting condition, wherein the first starting condition comprises the following steps: