Range extender idle speed control method and related device

Abstract

The present invention discloses a range extender idle speed control method and related devices, which can set the required torque of the engine and the generator to 0 when the power generation demand of the range extender is 0; determine whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and control the actual speed of the generator to drop to the target speed; if the engine enters its own idle speed control state during the period when the actual speed of the generator is controlled to drop to the target speed, then the actual speed of the generator is controlled to maintain at the target speed and after the duration of the target speed reaches the target duration, the control mode of the generator is switched to torque control, and the torque is controlled to 0, so that the engine maintains idle speed. The present invention can perform corresponding auxiliary speed regulation based on the generator at different stages of the engine entering the idle speed process, so that the engine speed can be smoothly transitioned to avoid shaking or shutdown of the engine during the idle speed process.

Description

Technical Field

[0001] The invention relates to the field of engines, and in particular to a range extender idle speed control method and related devices. Background Art

[0002] If the engine in the range extender system is matched with mechanical accessories, when the vehicle controller controls the range extender to have no power generation demand, the range extender will enter idle operation to maintain the normal working requirements of the accessory system. In the process of the range extender entering idle operation from a higher speed, if the vehicle has a large accessory working demand at this time, the engine will easily experience large speed fluctuations when entering idle, and the process of returning to idle speed cannot be burned in time to generate large torque for accessory needs, and the engine may even shut down directly during the process of returning to idle speed. How to achieve a smooth speed transition when the engine enters idle speed has become a technical problem that needs to be solved urgently by people in this field. Summary of the invention

[0003] In view of the above problems, the present invention provides a range extender idle speed control method and related devices that overcome the above problems or at least partially solve the above problems.

[0004] In a first aspect, a range extender idle speed control method includes:

[0005] When the power generation demand of the range extender is 0, the required torques of the engine and the generator are set to 0;

[0006] Determining whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and controlling the actual speed of the generator to drop to a target speed, wherein the target speed is lower than the idle speed of the engine;

[0007] If the engine enters a self-idle speed control state during the period when the actual speed of the generator is controlled to drop to the target speed, the actual speed of the generator is controlled to be maintained at the target speed, wherein the self-idle speed control state is obtained based on the message detection of the ECU;

[0008] When the actual speed of the generator is maintained at the target speed for a target time, the control mode of the generator is switched to torque control, and the torque of the generator is controlled to 0, so that the engine maintains idling.

[0009] Optionally, in some optional implementations, determining whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and controlling the actual speed of the generator to drop to a target speed includes:

[0010] When the actual torque of the engine is lower than the preset torque, the control mode of the generator is switched to speed control, and the actual speed of the generator is controlled to drop to a target speed.

[0011] Optionally, in some optional embodiments, when the actual torque of the engine is lower than the preset torque, switching the control mode of the generator to speed control, and controlling the actual speed of the generator to drop to the target speed, includes:

[0012] When the actual torque of the engine is lower than the preset torque, switching the control mode of the generator to speed control;

[0013] After the control mode of the generator is switched to the speed control, the actual speed of the generator is controlled to drop to the target speed according to a preset slope, wherein the preset slope is obtained in advance based on a bench verification of the effect of different slopes on idle speed fluctuation.

[0014] Optionally, in certain optional embodiments, the target duration matches the ambient temperature of the engine and the water temperature of the engine, and the lower the temperature, the longer the target duration.

[0015] In a second aspect, a range extender idle speed control device includes: a required torque setting unit, a control mode determination unit, an actual speed control unit, and a torque control switching unit;

[0016] The required torque setting unit is used to set the required torques of the engine and the generator to 0 when the required power generation power of the range extender is 0;

[0017] The control mode determination unit is used to determine whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and control the actual speed of the generator to drop to a target speed, wherein the target speed is lower than the idle speed of the engine;

[0018] The actual speed control unit is used to control the actual speed of the generator to maintain at the target speed if the engine enters a self-idle control state during the period when the actual speed of the generator is controlled to drop to the target speed, wherein the self-idle control state is obtained based on the message detection of the ECU;

[0019] The torque control switching unit is used to switch the control mode of the generator to torque control when the actual speed of the generator is maintained at the target speed for a target time, and control the torque of the generator to 0 so that the engine maintains idle speed.

[0020] Optionally, in certain optional implementations, the control mode determination unit includes: a control mode determination subunit;

[0021] The control mode determination subunit is used to switch the control mode of the generator to speed control when the actual torque of the engine is lower than the preset torque, and control the actual speed of the generator to drop to the target speed.

[0022] Optionally, in certain optional embodiments, the control mode determination subunit includes: a speed control switching subunit and a speed reduction subunit;

[0023] The speed control switching subunit is used to switch the control mode of the generator to speed control when the actual torque of the engine is lower than the preset torque;

[0024] The speed reduction subunit is used to control the actual speed of the generator to drop to the target speed according to a preset slope after the control mode of the generator is switched to the speed control, wherein the preset slope is obtained in advance based on a test bench to verify the influence of different slopes on idle speed fluctuations.

[0025] In a third aspect, a computer-readable storage medium stores a program, and when the program is executed by a processor, the idle speed control method of the range extender described in any one of the above items is implemented.

[0026] In a fourth aspect, an electronic device comprises at least one processor, and at least one memory and a bus connected to the processor; wherein the processor and the memory communicate with each other via the bus; and the processor is used to call program instructions in the memory to execute any one of the range extender idle speed control methods described above.

[0027] By means of the above technical scheme, the present invention provides a range extender idle speed control method and related device, which can set the required torque of the engine and the generator to 0 when the power generation demand of the range extender is 0; determine whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and control the actual speed of the generator to drop to the target speed, wherein the target speed is lower than the idle speed of the engine; if the engine enters its own idle speed control state during the period of controlling the actual speed of the generator to drop to the target speed, then control the actual speed of the generator to maintain at the target speed, wherein the self-idle speed control state is obtained based on the message detection of the ECU; when the actual speed of the generator is maintained at the target speed for a duration reaching the target time, switch the control mode of the generator to torque control, and control the torque of the generator to 0, so that the engine maintains idle speed. It can be seen from this that the present invention can perform corresponding auxiliary speed regulation based on the generator at different stages of the engine entering the idle speed process, so that the engine speed can be smoothly transitioned to avoid jitter or shutdown of the engine during the idle speed process.

[0028] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0030] Figure 1 A flow chart showing a first range extender idle speed control method provided by the present invention is shown;

[0031] Figure 2 A flow chart showing a second range extender idle speed control method provided by the present invention is shown;

[0032] Figure 3 A flow chart showing a third range extender idle speed control method provided by the present invention is shown;

[0033] Figure 4 The structure schematic diagram of the first range extender idle speed control device provided by the present invention is shown;

[0034] Figure 5 A schematic structural diagram of a second range extender idle speed control device provided by the present invention is shown;

[0035] Figure 6 The schematic diagram of the structure of the third range extender idle speed control device provided by the present invention is shown;

[0036] Figure 7 A structural schematic diagram of an electronic device provided by the present invention is shown. DETAILED DESCRIPTION

[0037] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0038] like Figure 1 As shown, the present invention provides a range extender idle speed control method, including: S100, S200, S300 and S400;

[0039] S100, when the power generation demand of the range extender is 0, the required torques of the engine and the generator are set to 0;

[0040] Optionally, if the engine in the range extender system is matched with a mechanical accessory, when the controller of the whole vehicle controls the range extender to have no power generation demand (i.e., the power generation demand power is 0), the range extender system enters idle operation (i.e., the engine enters idle operation) to maintain the working requirements of the accessory system. The present invention does not make any requirements for this.

[0041] Optionally, when the power generation demand of the range extender is 0, the present invention can further determine the control mode of the engine and the generator. There are generally two control modes for the generator: one is torque control, which means that the generator generates the same torque as the vehicle controller sends the required torque to the generator; the other is speed control, which means that the generator maintains the same speed as the vehicle controller sends the required speed to the generator. The present invention does not limit this.

[0042] It can be seen from this that when the power generation demand of the range extender is 0, the present invention can control the required torque of the engine and the generator to 0 in a torque control manner, so that the actual torque of the generator gradually decreases, and the present invention does not limit this.

[0043] It should be noted that the required torque can be understood as the target torque, and a certain process is required to reach the target torque. During this period, the present invention can continuously obtain the actual torque of the engine to execute the following S200, and the present invention does not impose any limitation on this.

[0044] S200, determining whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and controlling the actual speed of the generator to drop to a target speed, wherein the target speed is lower than the idle speed of the engine;

[0045] For example, Figure 2 As shown, in some optional embodiments, the S200 includes: S210;

[0046] S210: When the actual torque of the engine is lower than the preset torque, the control mode of the generator is switched to speed control, and the actual speed of the generator is controlled to drop to a target speed.

[0047] Optionally, the preset torque mentioned in the present invention can be obtained by pre-testing the bench. It should be noted that when the actual torque of the engine is lower than the preset torque, it means that the engine has been gradually reducing the torque in the direction of torque being 0, and has dropped to the triggering condition of the present invention (i.e., lower than the preset torque). Therefore, the present invention can switch to a speed control mode to facilitate the subsequent control of the speed of the generator, and the speed of the engine can be lowered to idle speed by controlling the speed of the generator to decrease, and the present invention does not limit this.

[0048] Optionally, the preset torque represents the degree of engine torque clearance during the process of engine torque clearance, when the generator starts speed control. For example, the current power demand is 0, and the engine torque demand is controlled to be 0, but the actual engine may still be working at a large torque, such as 1000Nm. In the process of the engine torque dropping from 1000Nm to 0, when the torque drops to the preset torque (such as: 200Nm), the generator starts to intervene in speed control. The purpose of retaining a certain engine torque value is to prevent the accessory torque from being too large at this time, so that the generator intervenes in advance. If the generator controls the speed after the engine torque is completely 0, the speed may fluctuate at this time.

[0049] For example, Figure 3 As shown, in some optional embodiments, the S210 includes: S211 and S212;

[0050] S211, when the actual torque of the engine is lower than the preset torque, switching the control mode of the generator to speed control;

[0051] S212. After the control mode of the generator is switched to the speed control, the actual speed of the generator is controlled to drop to the target speed according to a preset slope, wherein the preset slope is obtained in advance based on a bench verification of the effect of different slopes on idle speed fluctuation.

[0052] Optionally, the preset slope represents the rate of decrease of the generator speed in a unit time. The larger the preset slope, the faster the generator speed decreases. This preset slope can be calibrated according to a decrease of 100 to 300 revolutions per second, and the effect of different decrease slopes on idle fluctuations can be verified by a test bench. In theory, a decrease too fast will cause speed fluctuations, and a decrease too slow will affect the return to idle time, causing the return to idle time to be too long. Of course, the present invention can also be understood as the engine also decreasing the speed according to this slope, and the present invention is not limited to this.

[0053] Optionally, reducing the generator speed according to a preset slope can prevent a large accessory work demand during the engine speed reduction process, which causes the engine speed to drop too quickly. The present invention does not impose any restrictions on this.

[0054] Optionally, the target speed can be lower than a certain value of the engine idle speed. For example, the target speed = engine idle speed value + a certain value (this value is obtained in advance through calibration and can be set to a negative value). It should be noted that the engine idle speed value is a fixed data developed based on the engine model. Engines with different horsepower correspond to different idle speed values. This idle speed value is the idle speed value of the engine itself on the current vehicle.

[0055] Optionally, a target speed lower than the engine idle value can ensure that the engine will not stall, because when the vehicle controller controls the engine demand torque to 0, the engine will automatically enter the control of maintaining its own idle speed. If the generator lowers the engine speed, the engine will spray more fuel to reach its own idle speed value, so it will not stall.

[0056] S300, if the engine enters a self-idle speed control state during the period when the actual speed of the generator is controlled to drop to the target speed, the actual speed of the generator is controlled to be maintained at the target speed, wherein the self-idle speed control state is obtained based on the message detection of the ECU;

[0057] Optional, this self-idle speed control state means that the engine controller makes a judgment based on its own speed value. When its own speed value is lower than the idle value, the engine controller will enter the self-idle speed control state. For example, the idle speed value of the engine is 700 rpm. If the engine speed drops from 1000 rpm to 680 rpm, then the engine is in the free deceleration stage from 1000 to 680 rpm, and no fuel is sprayed until the speed is lower than 680 rpm. The engine enters the self-idle speed control state, and the engine will spray fuel at this time. The purpose of spraying fuel is to prevent the engine speed from being lower than the idle value.

[0058] S400: When the actual speed of the generator is maintained at the target speed for a target time, the control mode of the generator is switched to torque control, and the torque of the generator is controlled to 0, so that the engine maintains idling.

[0059] Optionally, when the generator speed drops to the target speed according to a preset slope, the engine's own idle control state will be triggered, and the idle speed will be maintained for a certain period of time (i.e., target duration) after reaching the target speed. The present invention does not impose any restrictions on this.

[0060] Optionally, in certain optional embodiments, the target duration matches the ambient temperature of the engine and the water temperature of the engine, and the lower the temperature, the longer the target duration.

[0061] Optionally, the target duration can be modified according to the ambient temperature and the engine water temperature. The lower the temperature, the longer the target duration. For example, when the water temperature is 10 degrees, the corresponding maintenance time is about 3 seconds; when the water temperature is 0 degrees, the corresponding maintenance time is about 5 seconds; when the water temperature is -10 degrees, the corresponding maintenance time is about 7 seconds; when the water temperature is -20 degrees, the corresponding maintenance time is about 10 seconds. The present invention does not limit this.

[0062] Optionally, after the idle speed is maintained for a target time, the generator can be freed from the speed control mode. Therefore, the present invention can cancel the generator speed control, and the generator torque control is 0, at which time the engine has the ability to maintain the idle speed by itself.

[0063] Optionally, when the range extender returns to idle, the torque and speed requirements of the generator and the engine are coordinated and controlled to achieve a stable return to idle speed of the range extender, thereby reducing abnormal fluctuations in the engine idle speed or even shutdown caused by the uncertainty of the operation of the accessories.

[0064] During the process of the range extender returning to idle speed, the generator is controlled in different control states at different stages to achieve stable return of the engine to idle speed. The present invention can reduce the abnormal fluctuation of the engine idle speed or even shutdown caused by the uncertainty of the operation of the accessories.

[0065] like Figure 4 As shown, the present invention provides an idle speed control device for a range extender, comprising: a required torque setting unit 100, a control mode determination unit 200, an actual speed control unit 300 and a torque control switching unit 400;

[0066] The required torque setting unit 100 is used to set the required torques of the engine and the generator to 0 when the required power generation power of the range extender is 0;

[0067] The control mode determination unit 200 is used to determine whether to switch the control mode of the generator to speed control according to the actual torque of the engine, and control the actual speed of the generator to drop to a target speed, wherein the target speed is lower than the idle speed of the engine;

[0068] The actual speed control unit 300 is used to control the actual speed of the generator to maintain at the target speed if the engine enters a self-idle control state during the period when the actual speed of the generator is controlled to drop to the target speed, wherein the self-idle control state is obtained based on the message detection of the ECU;

[0069] The torque control switching unit 400 is used to switch the control mode of the generator to torque control when the actual speed of the generator is maintained at the target speed for a target time, and control the torque of the generator to 0 so that the engine maintains idle speed.

[0070] Optional, such as Figure 5 As shown, in some optional implementations, the control mode determination unit 200 includes: a control mode determination subunit 210;

[0071] The control mode determination subunit 210 is used to switch the control mode of the generator to speed control when the actual torque of the engine is lower than the preset torque, and control the actual speed of the generator to drop to the target speed.

[0072] Optional, such as Figure 6 As shown, in some optional embodiments, the control mode determination subunit 210 includes: a speed control switching subunit 211 and a speed reduction subunit 212;

[0073] The speed control switching subunit 211 is used to switch the control mode of the generator to speed control when the actual torque of the engine is lower than the preset torque;

[0074] The speed reduction subunit 212 is used to control the actual speed of the generator to drop to the target speed according to a preset slope after the control mode of the generator is switched to the speed control, wherein the preset slope is obtained in advance based on the test bench to verify the influence of different slopes on idle speed fluctuation.

[0075] The present invention provides a computer-readable storage medium having a program stored thereon, wherein when the program is executed by a processor, any of the above-mentioned range extender idle speed control methods is implemented.

[0076] like Figure 7As shown, the present invention provides an electronic device 70, which includes at least one processor 701, and at least one memory 702 and a bus 703 connected to the processor 701; wherein the processor 701 and the memory 702 communicate with each other through the bus 703; the processor 701 is used to call the program instructions in the memory 702 to execute any of the above-mentioned range extender idle control methods.

[0077] In the present invention, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0078] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0079] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined in the present invention may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in the present invention, but will conform to the widest scope consistent with the principles and novel features disclosed in the present invention.

[0080] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A range extender idle speed control method, characterized in that: include: When the power generation demand of the range extender is 0, the required torques of the engine and the generator are set to 0; When the actual torque of the engine is lower than the preset torque, switching the control mode of the generator to speed control; After the control mode of the generator is switched to the speed control, the actual speed of the generator is controlled to drop to the target speed according to a preset slope, wherein the preset slope is obtained in advance based on the test bench to verify the influence of different slopes on the idle speed fluctuation, and the target speed is lower than the idle speed of the engine; If the engine enters a self-idle speed control state during the period when the actual speed of the generator is controlled to drop to the target speed, the actual speed of the generator is controlled to be maintained at the target speed, wherein the self-idle speed control state is obtained based on the message detection of the ECU; When the actual speed of the generator is maintained at the target speed for a target time, the control mode of the generator is switched to torque control, and the torque of the generator is controlled to 0, so that the engine maintains idling.

2. The method according to claim 1, characterized in that: The target duration matches the ambient temperature of the engine and the water temperature of the engine. The lower the temperature, the longer the target duration.

3. A range extender idle speed control device, characterized in that: include: A required torque setting unit, a control mode determination unit, an actual speed control unit and a torque control switching unit; The required torque setting unit is used to set the required torques of the engine and the generator to 0 when the required power generation power of the range extender is 0; The control mode determination unit is used to switch the control mode of the generator to speed control when the actual torque of the engine is lower than the preset torque; after the control mode of the generator is switched to the speed control, control the actual speed of the generator to drop to the target speed according to a preset slope, wherein the preset slope is obtained in advance based on the test bench to verify the influence of different slopes on idle speed fluctuation, and the target speed is lower than the idle speed of the engine; The actual speed control unit is used to control the actual speed of the generator to maintain at the target speed if the engine enters a self-idle control state during the period when the actual speed of the generator is controlled to drop to the target speed, wherein the self-idle control state is obtained based on the message detection of the ECU; The torque control switching unit is used to switch the control mode of the generator to torque control when the actual speed of the generator is maintained at the target speed for a target time, and control the torque of the generator to 0 so that the engine maintains idle speed.

4. A computer-readable storage medium having a program stored thereon, characterized in that: When the program is executed by a processor, the range extender idle speed control method according to any one of claims 1 to 2 is implemented.

5. An electronic device, characterized in that: The electronic device includes at least one processor, and at least one memory and a bus connected to the processor; wherein the processor and the memory communicate with each other through the bus; the processor is used to call program instructions in the memory to execute the range extender idle control method as described in any one of claims 1 to 2.

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