CN102817732B - A kind of diesel injection controlling method of duel fuel engine and device - Google Patents

Abstract

The invention discloses a diesel injection control method for a dual-fuel engine, which includes: if the engine is running in a dual-fuel working mode, according to the first injection moment, the first injection time and the first injection time of the engine injector in the pure diesel working mode According to the current operating condition of the engine, obtain the second injection timing and the second injection time of the engine injector in the dual-fuel working mode; control the injector to start injecting fuel at the second injection timing, and control all The fuel injector injects fuel within the second injection time. The invention discloses a diesel injection control device for a dual-fuel engine.

Description

Diesel injection control method and device for a dual-fuel engine

technical field

The invention relates to the technical field of engines, in particular to a diesel injection control method and device for a dual-fuel engine.

Background technique

Diesel/gas dual-fuel engine refers to a dual-fuel engine that uses a small amount of diesel as the pilot fuel and gas as the main fuel. Gas dual-fuel engine and electronically controlled diesel/gas dual-fuel engine.

For non-electrically controlled diesel/gas dual-fuel engines, the control of diesel injection is realized by controlling the stepper motor to drive the throttle rack, mainly using the controller to obtain the range of throttle action, once the throttle action is detected, the fuel injector is controlled Start fuel injection, and then control and drive the displacement of the throttle rack according to the action range of the throttle, so as to realize the control of the fuel injection quantity.

However, in the above method, the timing of diesel injection cannot be controlled according to the operating conditions of the system; due to the low precision of the stepping motor, precise control of the amount of diesel injection cannot be realized; due to the slow response speed of the stepping motor, the transient diesel control response The performance is poor; therefore, the precise control of the diesel injection quantity cannot be realized. In addition, because there are no corresponding sensors and electronic actuators, it is impossible to make a judgment on the fault. When the diesel engine fails, the precise control of the diesel injection time and the diesel injection amount in the fault mode cannot be realized. Long-term operation will cause damage to the engine. Adverse effects and potential safety hazards. It can be seen that the above method cannot control the diesel injection timing and the precise control of the diesel injection quantity, so that the engine cannot work in an optimal state at most working conditions.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a dual-fuel engine diesel injection control method and device to achieve the purpose of precise control of diesel injection timing and diesel injection quantity.

To achieve the above object, the present invention provides a method for controlling diesel injection of a dual-fuel engine, comprising:

If the engine is running under the dual-fuel working mode, then according to the first injection moment, the first injection time and the current operating condition of the engine under the pure diesel working mode of the engine injector, obtain the dual-fuel working condition of the engine injector The second injection moment and the second injection time in the mode;

The fuel injector is controlled to start fuel injection at the second injection timing, and the fuel injector is controlled to inject fuel within the second injection time.

Preferably, in the above method, the controlling the injector to start injecting oil at the second injection time, and controlling the injector to inject oil at the second injection time includes:

Collecting the level signal of the positive electrode of the injector, the moment when the level signal changes from low level to high level is the first injection moment;

When the level signal of the positive pole of the fuel injector is at a high level and reaches the second injection timing in the dual-fuel working mode, control the negative pole of the fuel injector to be turned on so that the fuel injector starts to inject fuel ;

record the injection time of the injector;

When the recorded injection time is the second injection time of the fuel injector in the dual-fuel working mode, the negative electrode of the fuel injector is controlled to be disconnected, so that the fuel injector stops injecting fuel.

Preferably, the above method also includes:

After the first injection timing in the pure diesel working mode and before the second injection timing in the dual-fuel working mode, control to use gas as the fuel of the engine;

After the end of the second injection time in the dual-fuel working mode and before the end of the first injection time in the pure diesel working mode, the gas is controlled to be used as the fuel of the engine.

Preferably, the above method also includes:

If the engine is running in the pure diesel working mode, the fuel injector is controlled to start injecting fuel at the first injection time, and the fuel injector is controlled to inject fuel within the first injection time.

Preferably, the above method also includes:

Obtain the position information of the mode switching switch;

The engine is controlled to switch between the pure diesel working mode and the dual-fuel working mode according to the position information.

The present invention also provides a diesel injection control device for a dual-fuel engine, comprising:

The parameter acquisition module is used to obtain the engine fuel injector according to the first injection moment, the first injection time and the current engine operating condition of the engine injector in the pure diesel operating mode when the engine is running in the dual-fuel working mode. The second injection timing and the second injection time of the engine in the dual-fuel working mode;

The first control module is used to control the fuel injector to start fuel injection at the second injection timing, and control the fuel injector to inject fuel within the second injection time.

Preferably, in the above device, the first control module includes:

The collection unit is used to collect the level signal of the positive electrode of the fuel injector, and the moment when the level signal changes from low level to high level is the first injection moment;

The first control unit is used to control the negative pole of the fuel injector to be turned on when the level signal of the positive pole of the fuel injector is at a high level and reaches the second injection time in the dual-fuel working mode, so that all The fuel injector starts to inject fuel;

a recording unit, used to record the injection time of the fuel injector;

The second control unit is used to control to disconnect the negative electrode of the fuel injector so that the fuel injector stops injecting when the recorded injection time is the second injection time of the fuel injector in the dual-fuel working mode. Oil.

Preferably, the above-mentioned device also includes:

The second control module is used to control the use of gas as the fuel of the engine after the first injection timing in the pure diesel working mode and before the second injection timing in the dual-fuel working mode;

The third control module is configured to control the use of the gas as the fuel of the engine after the second injection time in the dual-fuel working mode ends and before the first injection time in the pure diesel working mode ends.

Preferably, the above-mentioned device also includes:

The fourth control module is used to control the fuel injector to start injecting fuel at the first injection time when the engine is running in the pure diesel working mode, and control the fuel injector to inject fuel at the first injection time Oil.

Preferably, the above-mentioned device also includes:

A mode information acquisition module, configured to acquire the position information of the mode switching switch;

A switching module, configured to control the engine to switch between the pure diesel working mode and the dual-fuel working mode according to the position information.

It can be seen that the diesel injection control method and device for a dual-fuel engine of the present invention obtains the first injection time, the first injection time, and the current operating condition of the engine according to the first injection time and the first injection time of the engine injector in the pure diesel operating mode, to obtain the The second injection timing and the second injection time in the dual-fuel working mode; control the injector to start injecting fuel at the second injection timing, and control the injector to inject fuel at the second injection time Oil. At the same time, consider the first injection moment and the first injection time under the pure diesel working mode and the current operating condition of the engine, and select the appropriate second injection moment and second injection time in the first injection time to control the fuel injection The engine injects fuel within the second injection time. On the basis of not changing the original pure diesel control mode, the present invention realizes the precise control of diesel injection time and diesel injection quantity in consideration of the current operating conditions, so that The engine runs at its best in dual-fuel mode, improving economy.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are For some embodiments of the present invention, those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the schematic flow chart of embodiment 1 of the diesel injection control method of dual-fuel engine of the present invention;

Fig. 2 is the general block diagram of the diesel injection control of dual-fuel engine of the present invention;

Fig. 3 is a schematic flow chart of the control method of injection timing and injection time of the present invention;

Fig. 4 is the schematic diagram that the present invention collects diesel injection time and diesel injection pulse width;

Fig. 5 is a schematic diagram of controlling diesel injection timing and diesel injection pulse width according to the present invention;

6 is a schematic flow chart of Embodiment 2 of the diesel injection control method for a dual-fuel engine of the present invention;

7 is a schematic structural view of Embodiment 1 of the diesel injection control device for a dual-fuel engine of the present invention;

Fig. 8 is a schematic structural diagram of Embodiment 2 of the diesel injection control device for a dual-fuel engine of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Referring to Fig. 1, Fig. 1 is a schematic flow chart of Embodiment 1 of a diesel injection control method for a dual-fuel engine provided by the present invention, and the specific flow for realizing said Embodiment 1 is as follows:

Step 101: If the engine is running in the dual-fuel working mode, then according to the first injection moment, the first injection time and the current operating condition of the engine in the pure diesel working mode of the engine injector, obtain the Second injection timing and second injection time in dual-fuel operation mode.

The second injection time is less than or equal to the first injection time, and the second injection time is less than or equal to the first injection time. Wherein, the injection time, that is, the diesel injection pulse width, refers to the high level time loaded to the diesel injector, that is, the continuous injection time of the injector.

Different types of engines have different numbers of injector cylinders. During the operation of the engine, the injectors of each cylinder inject oil alternately. The first injection moment and the first injection time of each cylinder injector in the pure diesel working mode will be determined by the current engine operating conditions; while in the dual fuel working mode, it is determined according to the fuel injector in the pure diesel working mode The injection timing and injection time of the vehicle and the current operating conditions jointly determine the second injection timing and the second injection time.

Step 102: Control the fuel injector to start fuel injection at the second injection time, and control the fuel injector to inject fuel within the second injection time.

Referring to Fig. 2, Fig. 2 is an overall block diagram of the diesel injection control of the dual-fuel engine provided by the present invention, including a main control unit, a co-control unit and the controlled object, namely the engine injector. Different types of engines have different numbers of fuel injector cylinders. Assuming that the engine fuel injector of the present invention has six cylinders, for each cylinder fuel injector, the main control unit is mainly used to control the fuel injector in the pure diesel operating mode. diesel injection timing and diesel injection time, while the main control unit and cooperative control unit are jointly used to control the diesel injection timing and diesel injection time of the injector in the dual-fuel working mode. Wherein, the cooperative control unit includes an acquisition module and a control module, the acquisition module is used to collect the first injection moment and the first injection time under the pure diesel working mode, and the control module is used to control the fuel injector of each cylinder The fuel injection is started at the second injection timing, and the fuel injectors of each cylinder are controlled to inject fuel within the second injection time.

The following method can be used to implement step 102 in Embodiment 1 of the present invention, as shown in Figure 3, Figure 3 is a schematic flow chart of the method for controlling the injection time and injection time provided by the present invention, and the specific steps are as follows:

301: Collect the level signal of the positive electrode of the fuel injector, when the level signal changes from low level to high level, it is the first injection moment of the fuel injector in the pure diesel working mode (ie start fuel injection time);

Referring to FIG. 4 , FIG. 4 is a schematic diagram of collecting diesel injection timing and diesel injection time provided by the present invention. The fuel injector wiring harness of the main control unit drives the high-end connection to the input terminal of the diesel injection time and diesel injection time acquisition module of the cooperative control unit, and collects the level change signal of the positive pole of the fuel injector by capturing the rising edge of the level. The moment when the level signal of the positive pole of the fuel injector changes from low level to high level is the first injection moment of the fuel injector in the pure diesel working mode; in addition, record the holding time of the positive high level of the fuel injector , until the moment when the level signal of the positive pole of the injector changes from high level to low level, that is, when the falling edge of the level is captured, the first injection time is reached.

302: When the level signal of the positive pole of the fuel injector is at a high level and reaches the second injection moment in the dual-fuel working mode, control to turn on the negative pole of the fuel injector so that the fuel injector starts fuel injection;

303: Record the injection time of the fuel injector;

304: When the recorded injection time is the second injection time of the injector in the dual-fuel working mode, control to disconnect the negative electrode of the injector, so that the injector stops injecting fuel.

Referring to Fig. 5, Fig. 5 is a schematic diagram of controlling diesel injection timing and diesel injection pulse width provided by the present invention, disconnecting the low end of the fuel injector harness and introducing a control module for the diesel injection timing and diesel injection time of the cooperative control unit. The control unit calculates the second diesel injection timing and the second diesel injection pulse width in the dual-fuel working mode according to the first injection timing and the first injection time in the pure diesel working mode and the current engine operating condition; when the acquisition module captures When it reaches the rising edge (that is, the positive pole of the injector changes from low level to high level) and reaches the second injection time under the dual-fuel working mode, the control module in the co-control unit controls the timing of turning on the diesel injection and the time of diesel injection. The control module drives the circuit (the negative electrode of the injector can be turned on or off by controlling the on-off control of the MOS tube), and starts the recording of the power-on time. When the power-on time reaches the second injection time, the co-control The unit closes the drive circuit of the control module, so as to realize the precise control of the diesel injection timing and the diesel injection pulse width in the dual-fuel working mode.

As mentioned above, the fuel injector driving end wiring harness of the main control unit is introduced into the co-control unit, and the co-control unit obtains the diesel injection timing and diesel injection pulse width controlled by the main control unit by collecting the time and time when the injector is at a positive high level, and then Cut off the original diesel injection pulse width to the set diesel injection pulse width in proportion to the diesel injection timing set by the co-control unit and the diesel substitution rate, so as to realize precise control of diesel injection timing and diesel injection quantity,

The diesel injection control method of the dual-fuel engine of the present invention, according to the first injection moment, the first injection time and the current operating condition of the engine of the engine injector in the pure diesel working mode, obtains the fuel injector in the dual-fuel operation The second injection timing and the second injection time in the mode; control the fuel injector to start injecting fuel at the second injection timing, and control the fuel injector to inject fuel at the second injection time. At the same time, consider the first injection moment and the first injection time under the pure diesel working mode and the current operating condition of the engine, and select the appropriate second injection moment and second injection time in the first injection time to control the fuel injection The engine injects fuel within the second injection time. On the basis of not changing the original pure diesel control mode, the present invention realizes the precise control of diesel injection time and diesel injection quantity in consideration of the current operating conditions, so that The engine runs at its best in dual-fuel mode, improving economy.

Referring to Fig. 6, Fig. 6 is a schematic flow chart of Embodiment 2 of a dual-fuel engine diesel injection control method provided by the present invention. The specific flow of Embodiment 2 is as follows:

601: Obtain position information of a mode switching switch, so as to control the engine to perform operation mode switching between the pure diesel operation mode and the dual-fuel operation mode according to the position information.

The mode switching switch can be designed to set two switching gears, and the two switching gears respectively correspond to the pure diesel working mode and the dual-fuel working mode.

602: Judging the working mode represented by the position information, when the position information represents that the engine is running in a pure diesel working mode, perform steps 503 to 505; when the position information represents that the engine is operating in dual fuel When running in the mode, execute step 506 to step 510.

603: According to the current operating conditions of the engine, obtain the first injection moment and the first injection time of the engine injector in the pure diesel working mode;

604: Control the fuel injector to start fuel injection at the first injection moment, and accumulate the injection time;

605: Control the fuel injector to stop fuel injection when the accumulated injection time reaches the first injection time, that is, control the fuel injector to inject fuel within the first injection time;

606: Obtain the second injection timing and the first injection timing of the engine injector in the dual-fuel working mode according to the first injection timing, the first injection time, and the current operating condition of the engine in the pure diesel working mode. 2 injection time;

607: After the first injection timing in the pure diesel working mode and before the second injection timing in the dual-fuel working mode, control to use gas as the fuel of the engine;

608: When the second injection timing is reached, control the injector to start injecting fuel at the second injection timing, and accumulate the injection time;

609: Control the fuel injector to stop fuel injection when the accumulated injection time reaches the second injection time, that is, control the fuel injector to inject fuel within the second injection time;

610: After the end of the second injection time in the dual-fuel working mode and before the end of the first injection time in the pure diesel working mode, control to use the gas as the fuel of the engine.

The diesel injection control method of the dual-fuel engine of the present invention not only realizes the precise control of the diesel injection timing and the diesel injection quantity, but also obtains the diesel injection quantity according to the diesel injection timing and the diesel injection time in the pure diesel mode. The fuel injection quantity replaced by gas can be obtained by subtracting the diesel injection quantity under dual-fuel mode from the diesel injection quantity, and then according to the conversion relationship between gas and diesel, the gas injection quantity of any working condition can be obtained, so that the gas injection quantity can be obtained. pulse width, so the work of bench calibration can be saved; in addition, the present invention can also realize one-key switching between pure diesel mode and dual fuel mode; no matter in which working mode, the control logic of the main control unit is not affected in any way, Therefore, the calibration work of the whole vehicle can be saved.

Referring to FIG. 7, FIG. 7 is a schematic structural diagram of Embodiment 1 of a diesel injection control device for a dual-fuel engine provided by the present invention, the device includes: a parameter acquisition module 11 for the engine in dual-fuel working mode During operation, the second injection timing and The second injection time: the first control module 12 is configured to control the fuel injector to start injecting fuel at the second injection timing, and control the fuel injector to inject fuel at the second injection time.

The second injection time is less than or equal to the first injection time, and the second injection time is less than or equal to the first injection time. Wherein, the injection time, that is, the diesel injection pulse width, refers to the high level time loaded to the diesel injector, that is, the continuous injection time of the injector.

The first control module 12 includes:

The collection unit 121 is used to collect the level signal of the positive pole of the fuel injector, and the time when the level signal changes from low level to high level is the first injection time; the first control unit 122 is used to When the level signal of the positive pole of the fuel injector is at a high level and reaches the second injection timing in the dual-fuel working mode, control the negative pole of the fuel injector to be turned on so that the fuel injector starts to inject fuel ; the recording unit 23 is used to record the injection time of the injector; the second control unit 24 is used to control Disconnect the negative pole of the fuel injector so that the fuel injector stops injecting fuel.

Invented a diesel injection control device for a dual-fuel engine, considering the first injection timing and the first injection time in the pure diesel working mode and the current operating conditions of the engine, and selecting an appropriate second injection timing and injection time within the first injection time The second injection time is to control the injector to inject fuel within the second injection time. On the basis of not changing the original pure diesel control mode, the present invention realizes the diesel injection time and The precise control of the diesel injection quantity makes the engine run in the best state in the dual fuel mode and improves the economy.

Referring to Fig. 8, Fig. 8 is a schematic structural diagram of Embodiment 2 of a diesel injection control device for a dual-fuel engine provided by the present invention, and the device includes:

The mode information acquiring module 21 is used to acquire the position information of the mode switching switch; the switching module 22 is used to control the engine to switch between the pure diesel working mode and the dual-fuel working mode according to the position information ; The parameter acquisition module 23 is used to obtain the engine fuel injection time, the first injection time and the current operating condition of the engine according to the first injection moment, the first injection time and the current operating condition of the engine under the pure diesel operating mode when the engine is running in the dual-fuel operating mode. The second injection timing and the second injection time of the injector in the dual-fuel working mode; the second control module 24 is used for the second injection timing in the dual-fuel working mode after the first injection timing in the pure diesel working mode Before the injection time, control to use gas as the fuel of the engine; the first control module 25 is used to control the fuel injector to start fuel injection at the second injection time, and control the fuel injector to start fuel injection at the second injection time. 2. Inject fuel within the injection time. The third control module 26 is configured to control the use of the gas as the fuel of the engine after the end of the second injection time in the dual-fuel working mode and before the end of the first injection time in the pure diesel working mode. The fourth control module 27 is used to control the fuel injector to start fuel injection at the first injection time when the engine is running in the pure diesel working mode, and control the fuel injector to start injecting fuel at the first injection time fuel injection.

The diesel injection control device of the dual-fuel engine of the present invention not only realizes the precise control of the diesel injection timing and the diesel injection quantity, but also obtains the diesel injection quantity according to the diesel injection timing and the diesel injection time in the pure diesel mode. The fuel injection quantity replaced by gas can be obtained by subtracting the diesel injection quantity under dual-fuel mode from the diesel injection quantity, and then according to the conversion relationship between gas and diesel, the gas injection quantity of any working condition can be obtained, so that the gas injection quantity can be obtained. pulse width, so the work of bench calibration can be saved; in addition, the present invention can also realize one-key switching between pure diesel mode and dual fuel mode.

It should also be noted that in this article, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations Any such actual relationship or order exists between. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The steps of the methods or algorithms described in connection with the embodiments disclosed herein may be directly implemented by hardware, software modules executed by a processor, or a combination of both. Software modules can be placed in random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other Any other known storage medium.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. A diesel injection control method for a dual-fuel engine, characterized in that, comprising: If the engine is running under the dual-fuel working mode, then according to the first injection moment, the first injection time and the current operating condition of the engine under the pure diesel working mode of the engine injector, obtain the dual-fuel working condition of the engine injector A second injection timing and a second injection time in the mode, wherein the second injection timing is less than or equal to the first injection timing, and the second injection time is less than or equal to the first injection time; controlling the fuel injector to start fuel injection at the second injection timing, and controlling the fuel injector to inject fuel within the second injection time; After the first injection timing in the pure diesel working mode and before the second injection timing in the dual-fuel working mode, control to use gas as the fuel of the engine; After the end of the second injection time in the dual-fuel working mode and before the end of the first injection time in the pure diesel working mode, the gas is controlled to be used as the fuel of the engine. 2. The method according to claim 1, characterized in that the said injector is controlled to start injecting fuel at the second injection time, and the injector is controlled to inject fuel at the second injection time Oils include: Collecting the level signal of the positive electrode of the injector, the moment when the level signal changes from low level to high level is the first injection moment; When the level signal of the positive pole of the fuel injector is at a high level and reaches the second injection timing in the dual-fuel working mode, control the negative pole of the fuel injector to be turned on so that the fuel injector starts to inject fuel ; record the injection time of the injector; When the recorded injection time is the second injection time of the fuel injector in the dual-fuel working mode, the negative electrode of the fuel injector is controlled to be disconnected, so that the fuel injector stops injecting fuel. 3. The method according to claim 1, characterized in that the method further comprises: If the engine is running in the pure diesel working mode, the fuel injector is controlled to start injecting fuel at the first injection time, and the fuel injector is controlled to inject fuel within the first injection time. 4. The method according to any one of claims 1 to 3, characterized in that the method further comprises: Obtain the position information of the mode switching switch; The engine is controlled to switch between the pure diesel working mode and the dual-fuel working mode according to the position information. 5. A diesel injection control device for a dual-fuel engine, characterized in that it comprises: The parameter acquisition module is used to obtain the engine fuel injector according to the first injection moment, the first injection time and the current engine operating condition of the engine injector in the pure diesel operating mode when the engine is running in the dual-fuel working mode. The second injection timing and the second injection time of the device in the dual-fuel working mode, wherein the second injection timing is less than or equal to the first injection timing, and the second injection time is less than or equal to the first injection time time; A first control module, configured to control the fuel injector to start injecting fuel at the second injection timing, and control the fuel injector to inject fuel within the second injection time; The second control module is used to control the use of gas as the fuel of the engine after the first injection timing in the pure diesel working mode and before the second injection timing in the dual-fuel working mode; The third control module is configured to control the use of the gas as the fuel of the engine after the second injection time in the dual-fuel working mode ends and before the first injection time in the pure diesel working mode ends. 6. The device according to claim 5, wherein the first control module comprises: The collection unit is used to collect the level signal of the positive electrode of the fuel injector, and the moment when the level signal changes from low level to high level is the first injection moment; The first control unit is used to control the negative pole of the fuel injector to be turned on when the level signal of the positive pole of the fuel injector is at a high level and reaches the second injection time in the dual-fuel working mode, so that all The fuel injector starts to inject fuel; a recording unit, used to record the injection time of the fuel injector; The second control unit is used to control to disconnect the negative electrode of the fuel injector so that the fuel injector stops injecting when the recorded injection time is the second injection time of the fuel injector in the dual-fuel working mode. Oil. 7. The device according to claim 5, further comprising: The fourth control module is used to control the fuel injector to start injecting fuel at the first injection time when the engine is running in the pure diesel working mode, and control the fuel injector to inject fuel at the first injection time Oil. 8. The device according to any one of claims 5 to 7, wherein the device further comprises: A mode information acquisition module, configured to acquire the position information of the mode switching switch; A switching module, configured to control the engine to switch between the pure diesel working mode and the dual-fuel working mode according to the position information.