CN110700956B

CN110700956B - Engine ignition control method and device

Info

Publication number: CN110700956B
Application number: CN201910854655.8A
Authority: CN
Inventors: 吕登科; 向守智; 常浩
Original assignee: Zhejiang Geely Holding Group Co Ltd; Geely Automobile Research Institute Ningbo Co Ltd
Current assignee: Zhejiang Geely Holding Group Co Ltd; Geely Automobile Research Institute Ningbo Co Ltd
Priority date: 2019-09-10
Filing date: 2019-09-10
Publication date: 2022-07-19
Anticipated expiration: 2039-09-10
Also published as: CN110700956A

Abstract

The invention discloses an engine ignition control method, which comprises the steps of receiving a starting instruction of an engine; controlling the crankshaft of the engine to rotate according to the starting instruction; acquiring ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is used for starting ignition when the engine starts and is one of a plurality of cylinders of the engine; acquiring current position information of a crankshaft; judging whether the target cylinder is at the ignition position or not according to the current position information and the ignition position information; and controlling the target cylinder of the engine to ignite when the target cylinder is at the ignition position. The invention is fixed on the target cylinder to ignite when being started each time, so that the vibration of starting each time has fixed frequency and amplitude, and has starting consistency, and a driver can not mistakenly think that the vehicle is abnormal because of inconsistent vibration when starting; the ignition device is applied to the three-cylinder engine, and the engine is fixed on the second cylinder for ignition when being started, so that the vibration aggravation of the three-cylinder engine caused by the unbalanced structure of the three-cylinder engine is avoided. The invention also discloses an engine ignition control device.

Description

Engine ignition control method and device

Technical Field

The invention relates to the technical field of engine ignition, in particular to an engine ignition control method and device.

Background

With the rapid development of economic society in China, automobiles bring convenience to life of people and present new challenges to national energy safety and environmental protection, so that the nation pays more and more attention to automobile energy conservation and emission reduction, and the nation promotes automobile enterprises to develop and apply advanced automobile energy conservation and emission reduction technologies through continuously strict regulations and standards.

When vehicles are designed, vehicles generally match a four-cylinder engine with a certain displacement according to preset vehicle dynamic performance indexes, and three-cylinder engines have the main defect of large vibration compared with four-cylinder engines due to asymmetric structures. However, the three-cylinder engine has incomparable advantages with the four-cylinder engine, for example, a group of piston connecting rod valve actuating mechanisms are omitted, so that the manufacturing cost is obviously reduced, the volume is reduced and the arrangement is easier, the mass is reduced, the friction is reduced, the fuel economy is better, and the like, so that the application of the three-cylinder engine is actively promoted, the fuel economy is improved and the emission is reduced while the same dynamic property as that of the traditional four-cylinder naturally aspirated engine is ensured, and the increasingly strict regulation requirements are met.

At present, the vibration of the three-cylinder engine at idle speed or medium and high rotating speed can be avoided by configuring parts such as a dual-mass flywheel, a balance shaft and the like and performing fine calibration work, but in the starting and stopping processes of the engine, because the rotating speed is low, the vibration caused by the unbalance of the three-cylinder engine is more obvious, most new vehicle models on the market at present have the start-stop function, the engine can be frequently started and stopped in the driving process, the traditional starter can only drag the engine to 200-300 r/min, because the engine can not be well fired and work at low rotating speed, and is easy to fire, the rotating speed can be greatly fluctuated in the starting process to cause the vibration of the vehicle, and different cylinders are used for alternate ignition in each starting, noise and vibration caused by starting are different, starting consistency is poor, and the experience of start-stop function is greatly reduced, so that no effective solution exists at present.

Disclosure of Invention

The invention aims to provide an engine ignition control method and device, and solves the technical problem that the consistency of vibration and starting is poor when a three-cylinder engine is started.

In order to solve the technical problem, the invention provides an engine ignition control method, which comprises the steps of receiving a starting instruction of an engine; controlling the crankshaft of the engine to rotate according to the starting instruction;

acquiring ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and is used for starting ignition when the engine is started;

acquiring current position information of the crankshaft;

judging whether the target cylinder is at an ignition position or not according to the current position information and the ignition position information;

controlling a target cylinder of the engine to fire when the target cylinder is in the firing position.

Further, the acquiring of the ignition position information of the target cylinder of the engine further comprises:

judging whether the rotating speed of the engine is greater than a preset rotating speed threshold value or not;

if the rotating speed of the engine is greater than the rotating speed threshold value, acquiring ignition position information of a target cylinder of the engine;

and if the rotating speed of the engine is not greater than the rotating speed threshold value, controlling a starter to increase the rotating speed of a crankshaft of the engine.

Further, the acquiring ignition position information of a target cylinder of the engine includes:

acquiring target cylinder information of the engine;

and acquiring the ignition position information of the target cylinder according to the target cylinder information.

Further, the ignition position information of the target cylinder is predetermined information, wherein determining the ignition position information of the target cylinder includes:

acquiring crankshaft position information and camshaft position information of an engine;

determining top dead center position information of a piston of the target cylinder according to the crankshaft position information and the camshaft position information;

and generating ignition position information of the target cylinder according to the top dead center position information of the piston of the target cylinder.

Further, the determining whether the target cylinder is at an ignition position according to the current position information and the ignition position information includes:

comparing the current position information with the ignition position information;

if the current position information is matched with the ignition position information, judging that the target cylinder is at the ignition position;

and if the current position information does not match the ignition position information, determining that the target cylinder is in a non-ignition position.

Correspondingly, the invention also provides an engine ignition control device, which comprises an engine, a controller and a crankshaft position sensor; the controller is respectively connected with the engine and the crankshaft position sensor,

the crankshaft position sensor is used for acquiring current position information of the crankshaft and sending the current position information of the crankshaft to the controller;

the controller is configured to: the method comprises the steps of receiving a starting instruction of an engine, controlling a crankshaft of the engine to rotate according to the starting instruction, obtaining ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and used for starting ignition when the engine is started, obtaining current position information of the crankshaft, judging whether the target cylinder is at an ignition position or not according to the current position information and the ignition position information, and controlling the target cylinder of the engine to ignite when the target cylinder is at the ignition position.

Further, the device further comprises a starter which is connected with the controller and used for dragging the crankshaft of the engine to rotate;

the controller is further configured to: judging whether the rotating speed of the engine is greater than a preset rotating speed threshold value, acquiring ignition position information of a target cylinder of the engine when the rotating speed of the engine is greater than the rotating speed threshold value, and controlling a starter to increase the rotating speed of a crankshaft of the engine when the rotating speed of the engine is not greater than the rotating speed threshold value.

Further, the controller is further configured to: acquiring target cylinder information of the engine, and acquiring ignition position information of the target cylinder according to the target cylinder information, wherein the ignition position information of the target cylinder is predetermined information.

Further, the device also comprises a camshaft position sensor, the camshaft position sensor is connected with the controller, and the camshaft position sensor is used for collecting position information of a camshaft of an engine and sending the position information to the controller;

the controller is further configured to: obtaining crankshaft position information and camshaft position information of an engine, determining top dead center position information of a piston of the target cylinder according to the crankshaft position information and the camshaft position information, and generating ignition position information of the target cylinder according to the top dead center position information of the piston of the target cylinder.

Further, the controller is further configured to: comparing the current position information with the ignition position information, judging that the target cylinder is at the ignition position when the current position information is matched with the ignition position information, and judging that the target cylinder is at the non-ignition position when the current position information is not matched with the ignition position information.

The implementation of the invention has the following beneficial effects:

(1) because the fixed target cylinder is fixed for ignition when starting each time, the vibration caused by starting each time has fixed frequency and amplitude, the starting consistency is higher, and a driver cannot mistakenly think that the vehicle is abnormal because of inconsistent vibration when starting;

(2) the ignition starting device is applied to the three-cylinder engine, and the cylinder which starts to ignite when the engine is started is fixed on the second cylinder, so that the aggravation of vibration caused by the unbalanced structure of the three-cylinder engine is avoided;

(3) the invention can drive the engine to a higher rotating speed through the auxiliary starting of the starter, ensures that the engine can be successfully started when only one cylinder is ignited, simultaneously, the engine can well catch fire to work at a high rotating speed, and reduces the vehicle vibration caused by rotating speed fluctuation in the starting process.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an engine ignition control apparatus according to an embodiment of the present invention;

FIG. 2 is a flow chart of an engine ignition control method provided by an embodiment of the present invention;

FIG. 3 is a flow chart of a method of controlling engine ignition provided by another embodiment of the present invention;

fig. 4 is a schematic diagram comparing a BSG motor provided by an embodiment of the present invention with a conventional starter starting process.

Wherein the reference numbers in the figures correspond to: 1. a three-cylinder engine body; 2. a motor pulley; 3. a BSG system; 4. a motor belt; 5. an engine pulley.

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 derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

In europe, under the push of carbon dioxide emission tax, manufacturers are beginning to popularize small-displacement gasoline engines or diesel vehicles with lower oil consumption; in China, according to requirements of development plans of energy-saving and new energy automobile industry (2012 and 2020), average oil consumption of automobiles is reduced, and the efficiency of engines is improved to be a new technical route. Driven by such policy factors, downsizing, turbine increase, and the like are becoming mainstream development paths of current gasoline vehicles.

The smaller the number of cylinders of the engine with the same displacement is, the larger the volume of each cylinder is, and the larger the cylinder diameter and the stroke are, namely the higher the low-speed torque is, which is regarded as the heavy of the engine with the small displacement; because the three-cylinder engine has one less cylinder and one set of valve, cam and piston connecting rod mechanism matched with the three-cylinder engine is less, the weight of the engine is reduced on the whole, and the oil consumption is lower; for the reasons mentioned above, three-cylinder engines are widely used.

However, the small-displacement three-cylinder engine has many disadvantages, for example, in the process of starting and stopping the engine, because the rotating speed of the transmission starter is low, the engine can not be well fired and work at low rotating speed, the engine is easy to fire, the vibration of the vehicle caused by the severe fluctuation of the rotating speed in the starting process can be caused, and the vibration caused by the unbalance of the three-cylinder engine is more obvious; in addition, the three-cylinder engine is started each time by using different cylinders for alternate ignition, noise and vibration caused by starting are different, starting consistency is poor, a user mistakenly thinks that the vehicle is abnormal, and the experience of start-stop function is greatly reduced.

Based on the above, the embodiment of the invention provides an engine ignition control method, device and system, which are mainly applied to a three-cylinder engine, a combination of a small-displacement three-cylinder engine and a BSG (belt Starter generator) motor (belt-driven starting and power generation all-in-one machine) is used, and fixed-cylinder ignition in the BSG starting process is developed, so that the defect of poor starting consistency in the starting processes of the three-cylinder engine and the traditional four-cylinder engine is overcome, and the aggravation of vibration caused by the unbalance of the structure of the three-cylinder engine can be avoided. The method can also be applied to an odd-cylinder engine, and when the number of cylinders of the engine is odd, the target cylinder is a cylinder positioned in the middle of all cylinders of the engine. The defect of poor starting consistency in the starting process of the odd-number cylinder machine can be avoided, and the vibration aggravation of the odd-number cylinder machine caused by the unbalance of the structure of the odd-number cylinder machine can be avoided.

The details are described below by way of examples.

Example 1

The structure of the ignition control system of the engine shown in fig. 1 is schematic, and the main body part of the system comprises a three-cylinder engine body 1, an accessory system and a BSG system 3.

The accessories of the accessory system are connected through a belt and can mutually transmit power, wherein the accessory system comprises a motor belt wheel 2, a motor belt 4 and an engine belt wheel 5, and the engine belt wheel 5 is rigidly connected with the crankshaft accessory side of the three-cylinder engine body 1. The BSG system 3 includes a motor body and a motor controller, and the BSG system can be used as a generator to charge a battery, and can also be used as a motor to drive other accessories and the engine to run by using the electric energy of the battery.

In the embodiment of the present invention, a 48v BSG system is taken as an example for description, and a 48v BSG motor in the embodiment of the present invention needs to be matched with a 48v battery to provide electric energy for the BSG motor; and at the same time, a DC/DC converter is required to convert the 48v voltage and the 12v voltage to charge the 12v battery of the vehicle, in which case the conventional generator of the vehicle can be eliminated.

Example 2

The embodiment of the invention provides an engine ignition control method which can be applied to odd-cylinder engines, such as three-cylinder engines and five-cylinder engines.

The three-cylinder engine is low in cost and small in size, meets the national regulation and standard for energy conservation and emission reduction of automobiles, and is widely popularized, so that the engine ignition control method provided by the embodiment is mainly applied to the three-cylinder engine. The method is particularly applied to a three-cylinder engine provided with a BSG motor (belt drive starting and power generating integrated machine), and is used in the process of starting and igniting the three-cylinder engine each time.

Referring to the flowchart of the engine ignition control method shown in fig. 2, the method includes the steps of:

s202, an engine starting command is received. Wherein, this step specifically includes: and detecting a signal that a driver starts the engine through a key or triggers automatic starting, and determining to acquire a starting instruction of the engine.

And S204, controlling the crankshaft rotation of the engine according to the starting command. Specifically, in this step, the starter is controlled to crank the engine according to the start instruction. Preferably, the starter is a BSG motor. After receiving a starting instruction of the engine, the controller sends a starting instruction to the BSG motor to control the BSG motor to drag the engine to start.

The starter in the present application uses the BSG motor for the following reasons.

The traditional starter can only drag the engine to 200-. The BSG motor has large torque and does not have the maximum dragging rotating speed limit of a traditional starter, and the engine can be dragged to a higher target rotating speed.

Referring to a comparison diagram of a BSG motor starting process with a conventional starter shown in fig. 4, where an upper curve is an engine speed curve for the BSG motor starting and a lower curve is an engine speed curve for the conventional 12v starter starting, it can be seen in fig. 4 that the BSG motor drags the engine speed to a target idle speed of 1000 rpm at 250ms, the engine speed curve for the BSG motor starting has less speed fluctuation compared to the conventional starter, and severe fluctuation of the speed during the starting process is eliminated, thereby reducing vibration, and the BSG motor starting time is greatly shortened.

And S206, judging whether the rotating speed of the engine is greater than a preset rotating speed threshold value. The traditional starter has low rotating speed, the rotating speed during the ignition of the engine is 200-300 rpm, the low-rotating-speed ignition easily causes the vibration caused by the fluctuation of the rotating speed, the combustion is insufficient or the engine is on fire when the rotating speed of the engine is too low, and if only one cylinder is ignited, the low-rotating-speed ignition cannot ensure the successful ignition of the cylinder. Therefore, in the embodiment, the preset rotation speed threshold is greater than 200-300 rpm, preferably, after multiple tests, the preset rotation speed threshold can be 500 rpm or more, and the engine rotation speed is higher than the threshold to perform oil injection ignition, so that the vibration caused by the engine fire or rotation speed fluctuation can be avoided, and the success of one-cylinder ignition can be ensured. Through multiple tests, the requirement can be met when the preset rotating speed threshold value is 500 rpm in a normal environment, namely, the vibration caused by fire or rotating speed fluctuation of an engine is avoided, and the requirement for successful ignition of one cylinder can be met.

If the engine speed is greater than the speed threshold value, S208 is executed, and the ignition position information of the target cylinder of the engine is obtained.

And if the rotating speed of the engine is not greater than the rotating speed threshold value, controlling a starter to increase the rotating speed of a crankshaft dragging the engine until the rotating speed of the crankshaft is increased to the rotating speed threshold value.

S208, acquiring ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and is used for starting ignition when the engine is started.

For a three-cylinder engine, the ignition interval angle is 720 degrees/3, namely 240 degrees, three crank throws are not in the same plane, the ignition sequence of the engine is 1-3-2, in the traditional starting process, different cylinders are used for alternate ignition in each starting, the noise and the vibration caused by each starting are different, the starting consistency is poor, and a driver can misunderstand that the vehicle is abnormal in each starting. And for the three-cylinder engine, when the first cylinder and the third cylinder are ignited, the vibration is intensified when the structure of the three-cylinder engine is unbalanced, so that when the three-cylinder engine is applied to the three-cylinder engine, the engine is ignited through the same second cylinder when the engine is started every time.

Preferably, acquiring ignition position information of a target cylinder of the engine includes: and acquiring target cylinder information of the engine, and acquiring ignition position information of the target cylinder according to the target cylinder information.

The ignition position information of the target cylinder is predetermined information, wherein the determining the ignition position information of the target cylinder comprises: acquiring crankshaft position information and camshaft position information of an engine; determining top dead center position information of a piston of a target cylinder according to the crankshaft position information and the camshaft position information; and generating ignition position information of the target cylinder according to the top dead center position information of the piston of the target cylinder.

The ignition position of the target cylinder is obtained by a camshaft position sensor and a crankshaft position sensor. The function of the crankshaft position sensor is to determine the position of the crankshaft, that is, the rotation angle of the crankshaft, and the ECU can know that the piston of the cylinder is close to the top dead center position according to the output signal of the crankshaft position sensor, but it is unclear which cylinder is, and a cylinder judgment signal needs to be matched, that is, a camshaft position sensor needs to provide information for the ECU, so that the camshaft position sensor is a sensor for providing a cylinder judgment positioning signal. The camshaft position sensor is also called a synchronization signal sensor. In the step, the position of each cylinder piston reaching the top dead center is collected by a crankshaft position sensor, meanwhile, the position of the target cylinder reaching the top dead center is determined by a camshaft position sensor, and the ignition position information of the target cylinder is generated according to the top dead center position information of the piston of the target cylinder. In a three-cylinder engine, namely a crankshaft sensor is combined with a camshaft position sensor to determine the top dead center of a piston of a second cylinder, namely the ignition position of the second cylinder is obtained.

S210, acquiring current position information of the crankshaft; and judging whether the target cylinder is at the ignition position or not according to the current position information and the ignition position information.

Before ignition, according to the ignition position information of the target cylinder acquired in the step S208, a crankshaft current position signal is acquired through a crankshaft sensor, and whether the target cylinder is at the ignition position is judged according to the current position information and the ignition position information.

The method specifically comprises the following steps: comparing the current position information with the ignition position information; if the current position information is matched with the ignition position information, the target cylinder is judged to be at the ignition position; and if the current position information does not match the ignition position information, determining that the target cylinder is in the non-ignition position.

When the present embodiment is applied to a three-cylinder engine of a BSG motor, the fixed target cylinder is the second cylinder located at the intermediate position.

If the target cylinder is detected to be in the ignition position, S212 is executed.

And S212, controlling the target cylinder of the engine to ignite when the target cylinder is at the ignition position.

If the target cylinder is in the non-firing position, the control logic in S210 continues to be used to detect the current position of the crankshaft.

The engine ignition control method provided by the embodiment is applied to a three-cylinder engine provided with a BSG motor, and is fixed in a second cylinder for ignition when being started every time, so that the aggravation of vibration caused by the unbalance of the structure of the three-cylinder engine is avoided; secondly, the fixed target cylinder is ignited at each starting, so that the vibration caused by each starting has fixed frequency and amplitude, and the starting consistency is higher; and thirdly, the engine can be dragged to a higher rotating speed through the auxiliary starting of the BSG motor, and the successful starting can be ensured when only one cylinder is ignited.

In addition, the embodiment can also be applied to an odd-cylinder engine of a BSG motor, when the number of cylinders of the engine is odd, and the target cylinder is a cylinder positioned in the middle of each cylinder of the engine, the vibration aggravation caused by the unbalance of the structure of the odd-cylinder engine can be avoided, so that the vibration caused by each starting has fixed frequency and amplitude, and the starting consistency is higher. For example, when applied to a five cylinder engine, the fixed target cylinder is the third cylinder located at the center.

Example 3

The embodiment of the invention provides an engine ignition control method.

Referring to another flowchart of the engine ignition control method shown in fig. 3, the method includes the steps of:

and S202, receiving an engine starting command. Wherein, this step specifically includes: and detecting a signal that a driver starts the engine through a key or triggers automatic starting, and determining to acquire a starting instruction of the engine.

S203, judging whether the BSG motor has a fault or not, if not, executing S204, and controlling a starter to drag the crankshaft of the engine to rotate according to a starting instruction. If so, the conventional 12V starter starting mode is used.

In this embodiment, it should be noted that although the BSG motor is added, the conventional 12V starter is not eliminated, and when the BSG motor fails and cannot be started, the BSG motor can still be started by the 12V starter. When judging whether the BSG motor has a fault, the fault can be obtained through system detection.

And S204, controlling the crankshaft rotation of the engine according to the starting command. Specifically, in the step, the BSG motor is controlled to drive the crankshaft of the engine to rotate according to the starting instruction. And after a starting instruction of the engine is acquired, sending a starting instruction to the BSG motor to control the BSG motor to drag the engine to start.

And S206, judging whether the rotating speed of the engine is greater than a preset rotating speed threshold value. The traditional starter has low rotating speed, the rotating speed during engine ignition is 200-300 rpm, the low-rotating-speed ignition easily causes the vibration caused by rotating speed fluctuation, the combustion is insufficient or the fire is generated when the rotating speed of the engine is too low, and if only one cylinder is ignited, the low-rotating-speed ignition cannot ensure the successful ignition of the cylinder. Therefore, in the embodiment, the preset rotation speed threshold is greater than 200-300 rpm, preferably, after multiple tests, the preset rotation speed threshold can be 500 rpm or more, and the engine rotation speed is higher than the threshold, and then the injection ignition is performed, so that the vibration caused by the engine fire or rotation speed fluctuation can be avoided, and the success of the ignition of one cylinder can be ensured. After multiple tests, the requirements can be met under normal environment, the room temperature is 26 ℃, the engine is normal temperature, and the preset rotating speed threshold value is 500 rpm, namely, the vibration caused by fire or rotating speed fluctuation of the engine is avoided, and the requirement for successful ignition of one cylinder can be met.

And if the rotating speed of the engine is not greater than the rotating speed threshold value, controlling the BSG motor to increase the rotating speed of the crankshaft of the engine until the rotating speed of the crankshaft is increased to the rotating speed threshold value.

Acquiring ignition position information of a target cylinder of the engine, including: and acquiring target cylinder information of the engine, and acquiring ignition position information of the target cylinder according to the target cylinder information.

The ignition position of the target cylinder is obtained by a camshaft position sensor and a crankshaft position sensor. The crankshaft position sensor is used for determining the position of a crankshaft, namely the rotation angle of the crankshaft, the ECU can know that a piston of a cylinder is close to the top dead center position according to an output signal of the crankshaft position sensor, but does not know which cylinder is, and a cylinder judgment signal is needed to be matched, namely, a camshaft position sensor is needed to provide information for the ECU, so that the camshaft position sensor is a sensor for providing a cylinder judgment positioning signal. The camshaft position sensor is also called a synchronization signal sensor. In the step, the position of each cylinder piston reaching the top dead center is collected by a crankshaft position sensor, meanwhile, the position of the target cylinder reaching the top dead center is determined by a camshaft position sensor, and the ignition position information of the target cylinder is generated according to the top dead center position information of the piston of the target cylinder. In a three-cylinder engine, namely a crankshaft sensor is combined with a camshaft position sensor to determine the top dead center of a piston of a second cylinder, namely the ignition position of the second cylinder is obtained.

Before ignition, according to the ignition position of the target cylinder obtained in the step S208, a crankshaft position signal is obtained only through a crankshaft sensor, and whether the target cylinder is at the ignition position is judged according to the current position information and the ignition position information.

The method specifically comprises the following steps: comparing the current position information with the ignition position information; if the current position information is matched with the ignition position information, judging that the target cylinder is at the ignition position; and if the current position information does not match the ignition position information, determining that the target cylinder is in a non-ignition position.

When the present embodiment is applied to an engine of a BSG motor, a fixed target cylinder is any cylinder, but the fixed target cylinder at each start is ensured to be the same fixed target cylinder, so that the vibration caused by each start has a fixed frequency and amplitude, and has higher starting consistency.

If the fixed target cylinder is detected to be in the ignition position, S212 is executed.

If the target cylinder is in the non-firing position, the control logic in S210 continues to be used to detect the current position signal of the crankshaft.

The engine ignition control method provided by the embodiment is applied to an engine provided with a BSG motor, and is fixed on the same fixed target cylinder for ignition when being started every time, on one hand, the fixed cylinder ignition enables the vibration caused by starting every time to have fixed frequency and amplitude, and has higher starting consistency; on the other hand, the BSG motor is used for assisting in starting, so that the engine can be dragged to a high rotating speed, and the successful starting can be ensured when only one cylinder is ignited.

Example 4

The embodiment of the invention provides an engine ignition control device which is applied to an odd-cylinder engine, such as a three-cylinder engine and a five-cylinder engine.

The three-cylinder engine is low in cost and small in size, meets the national regulation and standard for energy conservation and emission reduction of automobiles, and is widely popularized, so that the engine ignition control method provided by the embodiment is mainly applied to the three-cylinder engine. Specifically, the present embodiment is mainly applied to a three-cylinder engine mounted with a BSG motor.

The present embodiment provides a device corresponding to the engine ignition control method of embodiment 2. The control system specifically comprises a starter, an engine, a controller, a camshaft position sensor and a crankshaft position sensor. Wherein the starter is connected to the engine through a drive pulley train. The controller is connected to the engine and the crankshaft position sensor, respectively.

The crankshaft position sensor is used for acquiring current position information of the crankshaft and sending the current position information of the crankshaft to the controller.

The controller is used for: the method comprises the steps of receiving a starting instruction of an engine, controlling the crankshaft of the engine to rotate according to the starting instruction, obtaining ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and used for starting ignition when the engine is started, obtaining current position information of the crankshaft, judging whether the target cylinder is located at an ignition position or not according to the current position information and the ignition position information, and controlling the target cylinder of the engine to ignite when the target cylinder is located at the ignition position.

Wherein the controller is further configured to: and judging whether the rotating speed of the engine is greater than a rotating speed threshold value, acquiring ignition position information of a target cylinder of the engine when the rotating speed of the engine is greater than the rotating speed threshold value, and controlling a starter to increase the rotating speed of a crankshaft of the engine when the rotating speed of the engine is not greater than the rotating speed threshold value.

The traditional starter has low rotating speed, the rotating speed during the ignition of the engine is 200-300 rpm, the low-rotating-speed ignition easily causes the vibration caused by the fluctuation of the rotating speed, the combustion is insufficient or the engine is on fire when the rotating speed of the engine is too low, and if only one cylinder is ignited, the low-rotating-speed ignition cannot ensure the successful ignition of the cylinder. Therefore, in the embodiment, the preset rotation speed threshold is greater than 200-300 rpm, preferably, after multiple tests, the preset rotation speed threshold can be 500 rpm or more, and the engine rotation speed is higher than the threshold to perform oil injection ignition, so that the vibration caused by the engine fire or rotation speed fluctuation can be avoided, and the success of one-cylinder ignition can be ensured. Through multiple tests, the requirement can be met when the preset rotating speed threshold value is 500 rpm in a normal environment, namely, the vibration caused by fire or rotating speed fluctuation of an engine is avoided, and the requirement for successful ignition of one cylinder can be met.

The controller is further configured to: the method comprises the steps of obtaining target cylinder information of an engine, obtaining ignition position information of a target cylinder according to the target cylinder information, wherein the ignition position information of the target cylinder is predetermined information.

The camshaft position sensor is connected with the controller and used for acquiring position information of a camshaft of the engine and sending the position information to the controller;

the controller is further configured to: the method comprises the steps of obtaining crankshaft position information and camshaft position information of an engine, determining top dead center position information of a piston of a target cylinder according to the crankshaft position information and the camshaft position information, and generating ignition position information of the target cylinder according to the top dead center position information of the piston of the target cylinder.

The controller is further configured to: and comparing the current position information with the ignition position information, judging that the target cylinder is at the ignition position when the current position information is matched with the ignition position information, and judging that the target cylinder is at the non-ignition position when the current position information is not matched with the ignition position information.

The device in the embodiment is applied to a three-cylinder engine provided with a BSG motor (belt drive starting and power generation integrated machine), and the target cylinder is the second cylinder in the three-cylinder engine.

Specifically, the controller is an ECU (Electronic Control Unit Electronic controller); the starter is a BSG motor (belt drive starting and power generation integrated machine).

The engine ignition control device provided by the embodiment of the invention is applied to a three-cylinder engine provided with a BSG motor, and a target cylinder is fixed to be a second cylinder located in the middle. Firstly, the vibration aggravation caused by the unbalance of the structure of the three-cylinder machine is avoided; secondly, the fixed target cylinder is ignited at each starting, so that the vibration caused by each starting has fixed frequency and amplitude, and the starting consistency is higher; thirdly, the engine can be dragged to a higher rotating speed through the auxiliary starting of the BSG motor, and the successful starting can be ensured when only one cylinder is ignited.

Example 5

The engine ignition control apparatus provided in the present embodiment corresponds to the engine ignition control method of embodiment 3. The system specifically comprises a starter, an engine, a controller, a cam position sensor and a crankshaft position sensor. The starter includes a conventional 12V starter and a BSG motor.

Wherein the starter is connected with the engine through a driving pulley system. The controller is connected to the engine and the crankshaft position sensor, respectively.

The controller is configured to: the method comprises the steps of receiving a starting instruction of an engine, controlling the crankshaft of the engine to rotate according to the starting instruction, obtaining ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and is used for starting ignition when the engine is started, obtaining current position information of the crankshaft, judging whether the target cylinder is located at an ignition position or not according to the current position information and the ignition position information, and controlling the target cylinder of the engine to ignite when the target cylinder is located at the ignition position.

The controller also comprises a fault judgment module used for judging whether the BSG motor has faults or not, and if not, the starting module is executed to control the BSG motor to drag the crankshaft of the engine to rotate. If so, the conventional 12V starter starting mode is used. The controller controls the starter to drag the crankshaft of the engine to rotate; preferably, the starter is a 48v BSG motor.

Wherein the controller is further configured to: judging whether the rotating speed of the engine is greater than a rotating speed threshold value, when the rotating speed of the engine is greater than the rotating speed threshold value, acquiring the ignition position information of a target cylinder of the engine, and controlling a starter to increase the rotating speed of a crankshaft of the engine when the rotating speed of the engine is not greater than the rotating speed threshold value.

Further, the controller is an ECU (Electronic Control Unit) Electronic controller.

The engine ignition control device provided by the embodiment is applied to an engine provided with a BSG motor, and is fixed on the same fixed target cylinder for ignition when being started every time, on one hand, the fixed cylinder ignition enables the vibration caused by starting every time to have fixed frequency and amplitude, and has higher starting consistency; on the other hand, the BSG motor assists in starting, so that the engine can be dragged to a high rotating speed, and the successful starting can be ensured when only one cylinder is ignited.

It should be noted that, in the present specification, the embodiments are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other. The present invention provides an engine ignition control device, which has the same implementation principle and the same technical effects as those of the foregoing method embodiments, and for the sake of brief description, reference may be made to the corresponding contents in the foregoing method embodiments for the parts of the device embodiments that are not mentioned.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other ways. The apparatus embodiments described above are merely illustrative and, for example, the flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

Finally, it should be noted that: the above-mentioned embodiments are only specific embodiments of the present invention, which are used for illustrating the technical solutions of the present invention and not for limiting the same, and the protection scope of the present invention is not limited thereto, although the present invention is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: those skilled in the art can still make modifications or changes to the embodiments described in the foregoing embodiments, or make equivalent substitutions for some features, within the scope of the disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the above claims.

Claims

1. An engine ignition control method characterized by comprising:

receiving a starting instruction of an engine;

controlling the crankshaft of the engine to rotate according to the starting instruction;

acquiring ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and is used for fixedly starting ignition when the engine is started;

acquiring current position information of the crankshaft;

2. The engine ignition control method according to claim 1, characterized in that: the method for acquiring the ignition position information of the target cylinder of the engine further comprises the following steps:

if the rotating speed of the engine is larger than the rotating speed threshold value, acquiring ignition position information of a target cylinder of the engine;

3. The engine ignition control method according to claim 1, characterized in that: the acquiring of the ignition position information of the target cylinder of the engine includes:

acquiring target cylinder information of the engine;

4. The engine ignition control method according to claim 3, characterized in that: the ignition position information of the target cylinder is predetermined information, wherein the determining the ignition position information of the target cylinder comprises:

determining top dead center position information of a piston of the target cylinder according to the crankshaft position information and the camshaft position information; and generating ignition position information of the target cylinder according to the top dead center position information of the piston of the target cylinder.

5. The engine ignition control method according to claim 1, characterized in that: the judging whether the target cylinder is at the ignition position according to the current position information and the ignition position information comprises:

if the current position information is matched with the ignition position information, determining that the target cylinder is at the ignition position;

6. An engine ignition control device is characterized by comprising an engine, a controller and a crankshaft position sensor; the controller is respectively connected with the engine and the crankshaft position sensor,

the controller is configured to: the method comprises the steps of receiving a starting instruction of an engine, controlling a crankshaft of the engine to rotate according to the starting instruction, obtaining ignition position information of a target cylinder of the engine, wherein the target cylinder is a cylinder which is determined from a plurality of cylinders of the engine and is used for fixedly starting ignition when the engine is started, obtaining current position information of the crankshaft, judging whether the target cylinder is located at an ignition position according to the current position information and the ignition position information, and controlling the target cylinder of the engine to ignite when the target cylinder is located at the ignition position.

7. The engine ignition control apparatus according to claim 6, characterized in that: the device further comprises a starter which is connected with the controller and used for dragging the crankshaft of the engine to rotate;

8. The engine ignition control apparatus according to claim 6, characterized in that: the controller is further configured to: acquiring target cylinder information of the engine, and acquiring ignition position information of the target cylinder according to the target cylinder information, wherein the ignition position information of the target cylinder is predetermined information.

9. The engine ignition control apparatus according to claim 8, characterized in that: the device also comprises a camshaft position sensor, wherein the camshaft position sensor is connected with the controller and is used for acquiring position information of the engine camshaft and sending the position information to the controller;

10. The engine ignition control apparatus according to claim 6, characterized in that: the controller is further configured to: comparing the current position information with the ignition position information, judging that the target cylinder is at the ignition position when the current position information is matched with the ignition position information, and judging that the target cylinder is at the non-ignition position when the current position information is not matched with the ignition position information.