Engine shutdown control method and device for extended-range hybrid vehicle

Abstract

The invention discloses an engine stop control method and device for an extended-range hybrid vehicle, and the method comprises the steps: when the vehicle meets an engine stop working condition, requesting an engine to execute the zero clearing of torque after determining that an engine stop flag bit is set for a preset time, and requesting the rotating speed of a generator to be reduced to an idling rotating speed at the same time; issuing an engine stop instruction, controlling the torque of the generator according to the rotating speed of the generator to reduce the rotating speed of the generator to zero, and stopping the engine when the engine sends out the identification information of the stop state and the rotating speed of the generator is reduced to zero. The problem that in the prior art, when the engine of the extended-range hybrid vehicle is shut down, abnormal shaking is likely to be caused is solved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle technology, and in particular to an engine shutdown control method and device for an extended-range hybrid vehicle. Background Art

[0002] Because the operation of the engine of the range extender is not strongly related to the vehicle speed, the power operating point of the range extender is mainly determined by the power demand of the vehicle. When the range extender is not needed to generate electricity, the HCU (hybrid control unit) software will request the engine to shut down, and the power generation before the range extender shuts down depends on the power demand. If the power demand changes from a large value to 0, the engine needs to shut down quickly to meet the power request.

[0003] However, when the engine suddenly changes from a normal power generation condition to a shutdown condition, the shutdown vibration caused by the compression and rebound of the engine's torsional vibration spring will bring a more obvious vibration to the whole vehicle, causing abnormal shaking problems. Summary of the invention

[0004] In view of this, an object of the present invention is to provide an engine shutdown control method and device for an extended-range hybrid vehicle, aiming to solve the problem in the prior art that abnormal jitter is easily caused when the engine of the extended-range hybrid vehicle is shut down.

[0005] An object of the present invention is to provide an engine shutdown control method for an extended-range hybrid vehicle, the method comprising: When the vehicle meets the engine shutdown condition, and after determining that the engine shutdown flag is set for a preset time, the engine is requested to execute the torque reset, and the speed of the generator is requested to drop to the idle speed; An engine shutdown command is issued, and the torque of the generator is controlled according to the speed of the generator to reduce the speed of the generator to zero. The engine shutdown is completed when the engine sends out a shutdown status identification message and the generator speed is reduced to zero.

[0006] Furthermore, in the above-mentioned engine shutdown control method for the extended-range hybrid vehicle, before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the method further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If so, the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero is executed.

[0007] Furthermore, in the above-mentioned engine shutdown control method for the extended-range hybrid vehicle, before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the method further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If not, the request for the engine to execute the torque reset is executed again, and the speed of the generator is requested to decrease to the idle speed until the engine torque is reset and the speed of the generator decreases to the idle speed.

[0008] Furthermore, the engine shutdown control method for the extended-range hybrid vehicle further includes, after the step of determining that the engine torque is cleared and the speed of the generator drops to the idle speed: Determine whether the engine shutdown flag is set; If so, the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero is executed.

[0009] Furthermore, in the above-mentioned engine shutdown control method for the extended-range hybrid vehicle, the step of judging whether the engine torque is cleared and whether the speed of the generator drops to the idle speed comprises: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed and lasts for a preset time.

[0010] Furthermore, in the above-mentioned engine shutdown control method for the extended-range hybrid vehicle, the step of controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero includes: The torque of the generator is controlled at a preset rate according to the speed of the generator to quickly reduce the speed of the generator to zero.

[0011] Furthermore, in the above-mentioned engine shutdown control method for the extended-range hybrid vehicle, before the step of issuing the engine shutdown command, the method further includes: If the vehicle meets the engine start conditions, the range extender is controlled to directly enter the power generation state to meet the power requirements of the vehicle.

[0012] Another object of the present invention is to provide an engine shutdown control device for an extended-range hybrid vehicle, the device comprising: A request module, used for requesting the engine to execute torque clearing when the vehicle meets the engine shutdown condition and after determining that the engine shutdown flag is set for a preset time, and at the same time requesting the generator speed to drop to the idle speed; The control module is used to issue an engine shutdown command, control the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, and wait for the engine to send out a shutdown status identification information and the generator speed is reduced to zero to complete the engine shutdown.

[0013] Another object of the present invention is to provide an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the program.

[0014] The present invention requests the engine to execute torque reset when the vehicle meets the engine shutdown condition and after determining that the engine shutdown flag is set for a preset time, and requests the generator speed to drop to the idle speed at the same time; issues an engine shutdown command, controls the generator torque according to the generator speed to reduce the generator speed to zero, waits for the engine to send out shutdown status identification information and the generator speed is reduced to zero to complete the engine shutdown, and when the whole vehicle meets the shutdown condition, delays confirmation processing is performed on the condition to avoid frequent start and stop of the engine; when it is confirmed that the whole vehicle needs to shut down the engine, the engine's execution torque is reset, and the generator speed is requested to drop to the engine's idle speed at the same time, and the engine is shut down when it is in an idle idle state, which can well improve the problem of abnormal jitter during shutdown, and solves the problem of abnormal jitter easily caused when the engine of an extended-range hybrid vehicle is shut down in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a flow chart of the engine shutdown control method of the extended-range hybrid vehicle in the first embodiment of the present invention; Figure 2 4 is a structural block diagram of an engine shutdown control device for an extended-range hybrid vehicle in a third embodiment of the present invention.

[0016] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0017] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0018] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0020] Embodiment 1 See also Figure 1 , which shows an engine shutdown control method for an extended-range hybrid vehicle in a first embodiment of the present invention, and the method includes steps S10-S11.

[0021] Step S10, when the vehicle meets the engine shutdown condition, and after determining that the engine shutdown flag is set for a preset time, the engine is requested to execute torque clearing, and the generator speed is requested to drop to the idle speed.

[0022] Among them, when the whole vehicle meets the engine shutdown conditions, the HCU (hybrid control unit) will first confirm the time dimension of the internal engine shutdown conditions before requesting the engine shutdown. The purpose is to prevent the engine from starting and stopping frequently. Specifically, it determines whether the engine shutdown flag is set and has lasted for a certain period of time. Secondly, the HCU requests the engine to execute torque reset and requests the generator speed to drop to the idle speed. The engine is shut down when it is in the idle idle state, which can greatly improve the shutdown NVH and vibration performance.

[0023] Step S11, issuing an engine shutdown command, controlling the torque of the generator according to the generator speed to reduce the generator speed to zero, and waiting for the engine to send out a shutdown status identification information and the generator speed to be reduced to zero to complete the engine shutdown.

[0024] Among them, when the engine speed and torque both drop to near the target value, for example, the engine torque is reset to zero and the generator speed drops to the idle speed, the HCU (hybrid controller) software issues a shutdown command, thereby controlling the torque of the generator (negative torque) according to the generator speed to reduce the generator speed to zero. Finally, the engine sends a Stop state and the generator speed drops to 0, indicating the completion of this shutdown condition.

[0025] In addition, in some optional embodiments of the present invention, during the time period from when the vehicle meets the engine shutdown conditions to when the HCU sends a shutdown command to the engine, if the vehicle meets the engine start conditions, the HCU will re-enter the normal engine operation and power generation condition and will not enter the shutdown logic.

[0026] In summary, the present invention requests the engine to execute the torque reset when the vehicle meets the engine shutdown condition and after determining that the engine shutdown flag is set for a preset time, and at the same time requests the generator speed to drop to the idle speed; issues an engine shutdown command, controls the generator torque according to the generator speed to reduce the generator speed to zero, waits for the engine to send out the shutdown status identification information and the generator speed is reduced to zero to complete the engine shutdown, and when the whole vehicle meets the shutdown condition, a delayed confirmation process is performed on the condition to avoid frequent start and stop of the engine; when it is confirmed that the whole vehicle needs to shut down the engine, the engine's execution torque will be reset, and at the same time, the generator speed will be requested to drop to the engine's idle speed, and the engine will be shut down when it is in an idle idle state, which can well improve the problem of abnormal jitter during shutdown, and solves the problem of abnormal jitter easily caused when the engine of an extended-range hybrid vehicle is shut down in the prior art.

[0027] Embodiment 2 This embodiment also provides an engine shutdown control method for an extended-range hybrid vehicle. The engine shutdown control method for the extended-range hybrid vehicle in this embodiment is different from the engine shutdown control method for the extended-range hybrid vehicle in the first embodiment in that: Before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the method further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If not, the request for the engine to execute the torque reset is executed again, and the speed of the generator is requested to decrease to the idle speed until the engine torque is reset and the speed of the generator decreases to the idle speed.

[0028] Among them, when the engine and generator feedback their own execution torque and speed reach near the target value, that is, the torque is reset and the speed is at the idle speed and maintained for a certain period of time, the HCU will issue a shutdown command to the engine. When the engine and generator feedback their own execution torque and speed do not reach the target value, the engine execution torque is requested to be reset again, and the generator speed is requested to drop to the idle speed until the engine torque is reset and the generator speed drops to the idle speed, so as to ensure the working condition before the engine is shut down.

[0029] In addition, when the torque of the generator is controlled according to the speed of the generator to reduce the speed of the generator to zero, the torque of the generator is controlled at a preset rate to quickly reduce the speed of the generator to zero, so that the corresponding working condition can be reached as soon as possible.

[0030] In summary, the engine shutdown control method for the extended-range hybrid vehicle in the above-mentioned embodiment of the present invention, when the vehicle meets the engine shutdown condition, and after determining that the engine shutdown flag is set for a preset time, requests the engine to execute the torque to be cleared, and at the same time requests the generator speed to drop to the idle speed; issues an engine shutdown command, controls the torque of the generator according to the generator speed to reduce the generator speed to zero, waits for the engine to send out the identification information of the shutdown state and the generator speed is reduced to zero to complete the engine shutdown, when the whole vehicle meets the shutdown condition, a delayed confirmation process will be performed on the condition to avoid frequent start and stop of the engine; when it is confirmed that the whole vehicle needs to shut down the engine, the engine's execution torque will be cleared, and at the same time, the generator speed will be requested to be reduced to the engine's idle speed, and the engine will be shut down when it is in an idle idle state, which can well improve the problem of abnormal jitter during shutdown, and solves the problem of abnormal jitter easily caused when the engine of the extended-range hybrid vehicle is shut down in the prior art.

[0031] In addition, the present invention has at least the following beneficial effects: 1. When the vehicle meets the shutdown conditions of the range extender (a power generation unit integrating the engine and the generator), the HCU will perform delayed confirmation processing for the condition to avoid frequent start and stop of the range extender; 2. When it is confirmed that the vehicle needs to shut down the range extender, the HCU software will clear the engine's execution torque and request the generator speed to be reduced to the engine's idle speed. The range extender will be shut down when it is in the idle idle state, which can greatly improve the shutdown NVH and vibration performance; During the time period from when the vehicle meets the range extender shutdown conditions to when the HCU sends a shutdown command to the engine, if the vehicle meets the range extender start conditions, the HCU will re-enter the normal working and power generation condition of the range extender and will not enter the shutdown logic.

[0032] Embodiment 3 See also Figure 2 , shown is an engine shutdown control device for an extended-range hybrid vehicle proposed in a third embodiment of the present invention, the device comprising: The request module 100 is used for requesting the engine to execute torque clearing when the vehicle meets the engine shutdown condition and after determining that the engine shutdown flag is set for a preset time, and at the same time requesting the speed of the generator to drop to the idle speed; The control module 200 is used to issue an engine shutdown command, control the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, and wait for the engine to send out a shutdown status identification information and the generator speed is reduced to zero to complete the engine shutdown.

[0033] Furthermore, in the above-mentioned engine shutdown control device for the extended-range hybrid vehicle, before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the step further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If so, the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero is executed.

[0034] Furthermore, in the above-mentioned engine shutdown control device for the extended-range hybrid vehicle, before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the step further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If not, the request for the engine to execute the torque reset is executed again, and the speed of the generator is requested to decrease to the idle speed until the engine torque is reset and the speed of the generator decreases to the idle speed.

[0035] Furthermore, the engine shutdown control device for the extended-range hybrid vehicle further comprises, after the step of determining that the engine torque is cleared and the speed of the generator drops to the idle speed: Determine whether the engine shutdown flag is set; If so, the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero is executed.

[0036] Furthermore, in the above-mentioned engine shutdown control device for the extended-range hybrid vehicle, the step of determining whether the engine torque is cleared and whether the speed of the generator drops to the idle speed comprises: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed and lasts for a preset time.

[0037] Furthermore, in the above-mentioned engine shutdown control device for the extended-range hybrid vehicle, the step of controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero comprises: The torque of the generator is controlled at a preset rate according to the speed of the generator to quickly reduce the speed of the generator to zero.

[0038] Furthermore, in the above-mentioned engine shutdown control device for the extended-range hybrid vehicle, before the step of issuing the engine shutdown command, the step further includes: If the vehicle meets the engine start conditions, the range extender is controlled to directly enter the power generation state to meet the power requirements of the vehicle.

[0039] The functions or operation steps implemented when the above modules are executed are substantially the same as those in the above device embodiments, and will not be described in detail here.

[0040] Embodiment 4 Another aspect of the present invention further provides a readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the steps of the method described in any one of the above embodiments 1 to 2 are implemented.

[0041] Embodiment 5 Another aspect of the present invention provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method described in any one of the above-mentioned embodiments one to two when executing the program.

[0042] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0043] Those skilled in the art will appreciate that the logic and / or steps represented in the flowchart or otherwise described herein, for example, may be considered as an ordered list of executable instructions for implementing logical functions, and may be specifically implemented in any computer-readable storage medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For purposes of this specification, a "computer-readable storage medium" may be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0044] More specific examples (a non-exhaustive list) of computer-readable storage media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable storage medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0045] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or a combination thereof: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0047] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An engine shutdown control method for an extended-range hybrid vehicle, characterized in that: The method comprises: When the vehicle meets the engine shutdown condition, and after determining that the engine shutdown flag is set for a preset time, the engine is requested to execute the torque reset, and the speed of the generator is requested to drop to the idle speed; An engine shutdown command is issued, and the torque of the generator is controlled according to the speed of the generator to reduce the speed of the generator to zero. The engine shutdown is completed when the engine sends out a shutdown status identification message and the generator speed is reduced to zero.

2. The engine shutdown control method for an extended-range hybrid vehicle according to claim 1, characterized in that: Before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the method further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If so, the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero is executed.

3. The engine shutdown control method for an extended-range hybrid vehicle according to claim 2, characterized in that: Before the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, the method further includes: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed; If not, the request for the engine to execute the torque reset is executed again, and the speed of the generator is requested to decrease to the idle speed until the engine torque is reset and the speed of the generator decreases to the idle speed.

4. The engine shutdown control method for an extended-range hybrid vehicle according to claim 3, characterized in that: After determining that the engine torque is cleared and the speed of the generator drops to the idle speed, the method further includes: Determine whether the engine shutdown flag is set; If so, the step of issuing the engine shutdown command and controlling the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero is executed.

5. The engine shutdown control method for an extended-range hybrid vehicle according to claim 4, characterized in that: The step of determining whether the engine torque is cleared and whether the speed of the generator drops to the idle speed comprises: Determine whether the engine torque is cleared and whether the generator speed drops to the idle speed and lasts for a preset time.

6. The engine shutdown control method for an extended-range hybrid vehicle according to claim 2, characterized in that: The step of controlling the torque of the generator according to the rotation speed of the generator to reduce the rotation speed of the generator to zero comprises: The torque of the generator is controlled at a preset rate according to the speed of the generator to quickly reduce the speed of the generator to zero.

7. The engine shutdown control method for an extended-range hybrid vehicle according to claim 1, characterized in that: Before the step of issuing the engine shutdown command, the method further includes: If the vehicle meets the engine start conditions, the range extender is controlled to directly enter the power generation state to meet the power requirements of the vehicle.

8. An engine shutdown control device for an extended-range hybrid vehicle, characterized in that: The device comprises: A request module, used for requesting the engine to execute torque clearing when the vehicle meets the engine shutdown condition and after determining that the engine shutdown flag is set for a preset time, and at the same time requesting the generator speed to drop to the idle speed; The control module is used to issue an engine shutdown command, control the torque of the generator according to the speed of the generator to reduce the speed of the generator to zero, and wait for the engine to send out a shutdown status identification information and the generator speed is reduced to zero to complete the engine shutdown.

9. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to any one of claims 1 to 7 when executing the program.

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