Vehicle Rotation Speed Control Method, Device and Computer Readable Storage Medium

Abstract

The present invention discloses a method, device and computer-readable storage medium for controlling the rotational speed of a vehicle. The method includes: obtaining a value of an ability parameter for adjusting the engine speed of a hybrid vehicle in a series hybrid mode; comparing the value of the ability parameter with a predetermined ability parameter threshold to obtain a comparison result; in the case where the comparison result is that the value of the ability parameter is less than the predetermined ability parameter threshold, obtaining the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed; determining the total demand power of the engine based on the vehicle demand power and the adjustment power; and determining the target speed of the engine based on the total demand power of the engine. The present invention solves the technical problem that in the related art, when the ability to adjust the engine speed is limited, the engine speed cannot be effectively adjusted.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control, and in particular, to a method and device for controlling the rotational speed of a vehicle and a computer-readable storage medium. Background Art

[0002] For a hybrid vehicle with a dual-motor hybrid system, in the series mode, the engine drives the generator to generate electricity, and the electric power is used to drive the motor to drive the vehicle; in the parallel mode, the clutch is engaged and the engine directly participates in driving the vehicle.

[0003] In the related art, when the hybrid vehicle is in the series mode, when the torque capacity of the generator is limited or the capacity of the power battery is limited, the generator cannot adjust the engine speed. That is, in the related art, when the torque capacity of the generator is limited or the capacity of the power battery is limited, there is a problem that the engine speed cannot be effectively adjusted.

[0004] In view of the above problems, no effective solution has been proposed yet. Summary of the Invention

[0005] Embodiments of the present invention provide a method and device for controlling the rotational speed of a vehicle and a computer-readable storage medium, so as to at least solve the technical problem that in the related art, when the ability to adjust the engine speed is limited, the engine speed cannot be effectively adjusted.

[0006] According to an aspect of an embodiment of the present invention, there is provided a method for controlling the rotational speed of a vehicle, including: obtaining a value of an ability parameter for adjusting the engine speed of a hybrid vehicle in a series hybrid mode; comparing the value of the ability parameter with a predetermined ability parameter threshold to obtain a comparison result; in a case where the comparison result is that the value of the ability parameter is less than the predetermined ability parameter threshold, obtaining a vehicle demand power for driving the hybrid vehicle and an adjustment power for adjusting the rotational speed of the engine from an actual rotational speed at a current moment to a reference rotational speed; determining a total demand power of the engine based on the vehicle demand power and the adjustment power; and determining a target rotational speed of the engine based on the total demand power of the engine.

[0007] Optionally, the adjustment power for adjusting the rotational speed of the engine from an actual rotational speed at a current moment to a reference rotational speed includes: determining, based on the actual rotational speed and the reference rotational speed, an adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed by using a proportional-integral (PI) algorithm.

[0008] Optionally, the reference speed is the optimal speed of the engine within a target period; wherein, the optimal speed of the engine within the target period is the speed corresponding to the total demand power of the engine within the target period.

[0009] Optionally, based on the actual speed and the reference speed, using a proportional-integral (PI) algorithm to determine the adjustment power required to adjust the speed of the engine from the actual speed at the current moment to the reference speed, including: based on the difference between the actual speed and the reference speed, using the PI algorithm to obtain the adjustment torque required to adjust the speed of the engine from the actual speed at the current moment to the reference speed; according to the adjustment torque and the actual speed, obtain the adjustment power required to adjust the speed of the engine from the actual speed at the current moment to the reference speed.

[0010] Optionally, determining the target speed of the engine based on the total demand power of the engine includes: obtaining the correspondence between the engine power and the engine speed; based on the correspondence, determining the target speed of the engine corresponding to the total demand power of the engine.

[0011] Optionally, comparing the value of the ability parameter with the ability parameter threshold to obtain a comparison result includes at least one of the following: when the value of the ability parameter includes the torque ability parameter of the generator in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the torque ability threshold of the generator, and the torque ability parameter is less than the torque ability threshold, determining that the value of the ability parameter is less than the predetermined ability parameter threshold; when the value of the ability parameter includes the charge and discharge ability parameter of the power battery in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the charge and discharge ability threshold of the power battery, and the charge and discharge ability parameter is less than the charge and discharge ability threshold, determining that the value of the ability parameter is less than the predetermined ability parameter threshold.

[0012] Optionally, after determining the target speed of the engine based on the total demand power of the engine, it further includes: obtaining the first torque corresponding to the actual speed of the engine at the current moment and the second torque corresponding to the target speed of the engine; based on the first torque and the second torque, determining the first torque change corresponding to the engine; controlling the second torque change corresponding to the generator in the series hybrid mode of the hybrid vehicle to be less than the first torque change.

[0013] Optionally, determining the total required power of the engine based on the vehicle required power and the adjustment power includes: determining the sum of the vehicle required power and the adjustment power as the total required power of the engine.

[0014] According to another aspect of the embodiments of the present invention, there is also provided a rotational speed control device for a vehicle, including: a first acquisition module configured to acquire a value of an ability parameter for adjusting the rotational speed of an engine in a series hybrid mode of a hybrid vehicle; a comparison module configured to compare the value of the ability parameter with a predetermined ability parameter threshold to obtain a comparison result; a second acquisition module configured to, when the comparison result is that the value of the ability parameter is less than the predetermined ability parameter threshold, acquire the vehicle required power for driving the hybrid vehicle and the adjustment power for adjusting the rotational speed of the engine from the actual rotational speed at the current moment to a reference rotational speed; a first determination module configured to determine the total required power of the engine based on the vehicle required power and the adjustment power; and a second determination module configured to determine the target rotational speed of the engine based on the total required power of the engine.

[0015] According to another aspect of the embodiments of the present invention, there is also provided a computer-readable storage medium, where the storage medium includes a stored program, and when the program runs, it controls the device where the storage medium is located to execute the rotational speed control method for a vehicle according to any one of the above.

[0016] In the embodiments of the present invention, by acquiring the value of the ability parameter for adjusting the rotational speed of the engine in the series hybrid mode of the hybrid vehicle, comparing the value of the ability parameter with the predetermined ability parameter threshold to obtain a comparison result, when the comparison result is that the value of the ability parameter is less than the predetermined ability parameter threshold, acquiring the vehicle required power for driving the hybrid vehicle and the adjustment power for adjusting the engine to the target operating state; determining the total required power of the engine based on the vehicle required power and the adjustment power; and determining the target rotational speed of the engine based on the total required power of the engine. The technical problem that the rotational speed of the engine cannot be effectively adjusted when the torque capacity of the generator is limited or the battery capacity is limited is solved. Description of the Drawings

[0017] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0018] Figure 1 is a flowchart of an optional rotational speed control method for a vehicle according to an embodiment of the present invention;

[0019] Figure 2It is a flowchart of another optional vehicle speed control method according to an embodiment of the present invention;

[0020] Figure 3 It is a structural block diagram of an optional vehicle speed control device according to an embodiment of the present invention. Detailed implementation manners

[0021] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order different from those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0023] Embodiment 1

[0024] According to an embodiment of the present invention, an embodiment of a vehicle speed control method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from that here.

[0025] It should be noted that the terms "first", "second", etc. in the description, claims and the above-mentioned drawings of the present application are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that such terms can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily limit to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0026] Now, exemplary embodiments according to the present application will be described in more detail with reference to the drawings. However, these exemplary embodiments can be implemented in many different forms and should not be construed as being limited only to the embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of the present application is thorough and complete, and the concept of these exemplary embodiments is fully conveyed to those of ordinary skill in the art.

[0027] Term Explanation

[0028] The power system of a series hybrid electric vehicle is mainly a power system composed of power assemblies such as an engine, a generator, and a drive motor in a series manner.

[0029] The power system of a parallel hybrid electric vehicle, in which the engine and the drive motor are both power assemblies, and the powers of the two major power assemblies can be superimposed and output, or can be output separately.

[0030] The power system of a hybrid hybrid electric vehicle combines the structures of a series type and a parallel type, and is mainly composed of three major power assemblies: an engine, an electric generator, and a drive motor.

[0031] Figure 1 is a flowchart of a vehicle speed control method according to an embodiment of the present invention, as Figure 1 shown, the method includes the following steps:

[0032] Step S102, obtain the value of the ability parameter for adjusting the engine speed of the hybrid electric vehicle in the series hybrid mode.

[0033] In some alternative embodiments, the value of the ability parameter for adjusting the engine speed includes the maximum driving torque of the generator and / or the maximum available charge and discharge power of the power battery. It should be understood that the driving torque of the generator is equal to the torque value when the generator torque is positive.

[0034] It should be understood that when a hybrid vehicle is in a series hybrid mode, there will be a problem that the generator cannot adjust the engine speed when the drive torque of the generator and the available charge and discharge power of the power battery are limited.

[0035] Step S104: Compare the value of the ability parameter with a predetermined ability parameter threshold to obtain a comparison result.

[0036] Step S106: When the comparison result is that the value of the ability parameter is less than the predetermined ability parameter threshold, obtain the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed.

[0037] In some alternative embodiments, when the generator torque ability is less than the corresponding generator torque ability parameter threshold, or the power battery ability is less than the corresponding power battery ability parameter threshold, obtain the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed.

[0038] In one embodiment, the vehicle demand power for driving the hybrid vehicle includes the demand power corresponding to the throttle opening when the driver steps on the accelerator and the power supplied to the accessories of the hybrid vehicle. Among them, the demand power corresponding to the throttle opening can be obtained through a correspondence table of the throttle opening and the demand power. Among them, the vehicle accessories include an air conditioning system, a lighting system, and so on. In one embodiment, the adjustment power for adjusting the engine to the target operating state is the power required for the engine to adjust its own operating range.

[0039] Step S108: Determine the total demand power of the engine based on the vehicle demand power and the adjustment power.

[0040] Step S110: Determine the target speed of the engine based on the total demand power of the engine.

[0041] In this alternative embodiment, by obtaining the value of the ability parameter for adjusting the engine speed in a series hybrid mode of a hybrid vehicle; comparing the ability parameter value with a predetermined ability parameter threshold to obtain a comparison result; in the case where the comparison result is that the ability parameter value is less than the predetermined ability parameter threshold, obtaining the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed; determining the total demand power of the engine based on the vehicle demand power and the adjustment power; and determining the target speed of the engine based on the total demand power of the engine. In the case where the value of the ability parameter for adjusting the engine speed is less than the predetermined ability parameter threshold, that is, when the ability to adjust the engine speed is limited, the target speed of the engine is determined by the vehicle demand power and the adjustment power of the engine, solving the technical problem that the engine speed cannot be effectively adjusted when the ability to adjust the engine speed is limited. It should be understood that the generator drive torque and the power battery charge and discharge power can characterize the value of the ability parameter for adjusting the engine speed.

[0042] Determining the total demand power of the engine based on the vehicle demand power and the adjustment power includes: determining that the sum of the vehicle demand power and the adjustment power is the total demand power of the engine.

[0043] In some alternative embodiments, obtaining the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed includes: based on the actual speed and the reference speed, using a proportional-integral (PI) algorithm to determine the adjustment power required for the engine to adjust the engine speed from the actual speed to the reference speed. It should be understood that the actual speed of the engine may be a dynamic value that changes over time. By using a proportional-integral (PI) algorithm to determine the adjustment power required for the engine to adjust the engine speed from the actual speed to the reference speed based on the actual speed and the reference speed, continuous adjustment and optimization of the adjustment power can be achieved. Thus, the adjustment power required for the engine to adjust the engine speed from the actual speed to the reference speed can be accurately and dynamically obtained.

[0044] In some alternative embodiments, the reference rotational speed for determining the adjusted rotational speed may be the optimal rotational speed of the engine within the target period, or a rotational speed value determined based on empirical values. Preferably, the reference rotational speed is determined as the optimal rotational speed of the engine within one operating cycle of the vehicle controller before the current moment. In the case where the optimal rotational speed data of the engine within one operating cycle of the vehicle controller before the current moment is missing, the aforementioned reference rotational speed may be determined based on the optimal rotational speed of the engine within the historical operating cycle of the vehicle controller closest to the current moment. Among them, the optimal rotational speed of the engine within the aforementioned target period can be obtained according to the total engine demand power of the engine within the target period and the corresponding relationship between the total engine demand power and the rotational speed. Determining the reference rotational speed based on the optimal rotational speed of the engine within the target period can update the reference rotational speed in real time. Thus, a reference rotational speed with high applicability can be obtained, and the accuracy and real-time performance of the adjustment power used to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed are high.

[0045] In an alternative embodiment, a method for determining the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed by using a proportional-integral (PI) algorithm based on the actual rotational speed and the reference rotational speed may include the following steps: obtaining the adjustment torque required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed by using a proportional-integral (PI) algorithm based on the difference between the actual rotational speed and the reference rotational speed; and obtaining the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed according to the adjustment torque and the actual rotational speed. The actual rotational speed is a dynamic value that changes with time. Based on the difference between the actual rotational speed and the reference rotational speed, the adjustment power required for the engine to adjust the rotational speed from the actual rotational speed to the reference rotational speed can be accurately and dynamically obtained through the proportional-integral (PI) algorithm.

[0046] In an alternative embodiment, a method for determining the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed by using a proportional-integral (PI) algorithm based on the actual rotational speed and the reference rotational speed may include the following steps:

[0047] Obtain the engine adjustment torque T according to the following method 调节 :

[0048] T 调节 = A×(V 参考 - V 实际 ) + B×∫(V 参考 - V 实际 )

[0049] where A is a predetermined proportionality coefficient, B is a predetermined integral coefficient, V 参考 and V 实际They are the reference speed and the actual speed of the engine respectively.

[0050] The engine adjustment power P is obtained by the following method 调节 :

[0051]

[0052] where C is a coefficient. In an optional embodiment, the value of C is 9550.

[0053] In some optional embodiments, the method for determining the target speed of the engine based on the total demand power of the engine may include the following steps: obtaining the correspondence between the engine power and the engine speed; based on the correspondence, determining the target speed of the engine corresponding to the total demand power of the engine. The aforementioned correspondence may be a relationship curve or a relationship function fitted according to empirical values, or a correspondence table between the total demand power of the engine and the engine speed pre-generated according to empirical values or theoretical values. Determining the target speed of the engine corresponding to the total demand power of the engine based on the correspondence can quickly and accurately obtain the target speed of the engine corresponding to the total demand power of the engine.

[0054] In some optional embodiments, the correspondence between the engine power and the engine speed is obtained based on the optimal fuel economy curve BSFC (Brake Specific Fuel Consumption).

[0055] In some optional embodiments, comparing the value of the ability parameter with the ability parameter threshold to obtain a comparison result includes at least one of the following: when the value of the ability parameter includes the torque ability parameter of the generator in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the torque ability threshold of the generator, and the torque ability parameter is less than the torque ability threshold, determining that the value of the ability parameter is less than the predetermined ability parameter threshold; when the value of the ability parameter includes the charge and discharge ability parameter of the power battery in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the charge and discharge ability threshold of the power battery, and the charge and discharge ability parameter is less than the charge and discharge ability threshold, determining that the value of the ability parameter is less than the predetermined ability parameter threshold. When the value of the ability parameter is less than the corresponding predetermined ability parameter threshold, it indicates that the device corresponding to the value of the ability parameter does not meet the requirement of providing adjustment for the engine speed, that is, it cannot effectively adjust the engine speed. Determining whether to determine the target speed of the engine according to the vehicle demand power and the adjustment power based on the value of the ability parameter and the corresponding predetermined ability parameter threshold can achieve effective adjustment of the engine speed when the abilities such as the torque ability of the generator or the ability of the power battery are limited.

[0056] In some alternative embodiments, after determining the target speed of the engine based on the total required power of the engine, the method further includes: obtaining a first torque corresponding to the current actual speed of the engine and a second torque corresponding to the target speed of the engine; determining a first torque change corresponding to the engine based on the first torque and the second torque; controlling the second torque change corresponding to the generator in the series hybrid mode of the hybrid vehicle to be less than the first torque change. The internal speed regulation of the engine is also achieved through torque regulation, and the torque regulation is related to processes such as intake air volume and ignition angle adjustment. Therefore, the regulation speed of the engine is slower than that of the generator. To ensure the stability of the speed control process, it is necessary to limit the torque change speed of the generator. By limiting the torque change speed of the generator, the responses of the engine and the generator are synchronized, achieving the purpose of ensuring stable speed control.

[0057] As an alternative embodiment, after determining the target speed of the engine based on the total required power of the engine, the method further includes: obtaining a second torque corresponding to the target speed of the engine based on the target speed of the engine and the total required power of the engine. When the torque that the engine can provide by itself is less than the second torque, the generator is used to provide auxiliary torque for the engine, where the sum of the auxiliary torque and the torque that the engine can provide by itself is less than the second torque, and the auxiliary torque is less than a predetermined generator torque. Thereby, it can effectively avoid the problem of insufficient engine power output caused by insufficient generator speed regulation ability, and can also avoid the problems of overcharging and over-discharging of the battery during the speed regulation process due to weak battery capacity, and can meet the torque requirements of the engine within the maximum range.

[0058] Based on the above embodiments and alternative embodiments, a method for controlling the speed of a vehicle is provided.

[0059] In the related art, based on the state of the vehicle clutch during driving, the engine speed control mode is divided into three different control modes. Then, by comprehensively considering the difference in speeds at both ends of the clutch and the fuel consumption and optimal curve of the engine, different engine target speeds and speed control request torques are obtained under different control modes. At the same time, the PID control algorithm is used to calculate the engine speed control request torque in the closed-loop control mode and the mode with both positive and negative torques. This method is only applicable to the case of adjusting the speed difference of the clutch during the series-parallel switching, and is not applicable to the series working condition.

[0060] It should be understood that for a hybrid vehicle configured with a dual-motor hybrid system, in its pure electric mode, the drive motor directly drives the vehicle. In the series mode, the engine drives the generator to generate electricity, and the generated electricity is used to drive the motor to drive the vehicle; in the parallel mode, the clutch engages, and the engine directly participates in driving the vehicle. For this hybrid system, the engine has full-time torque control. The vehicle controller sends a torque request to the engine, and the engine speed is regulated by the vehicle controller controlling the generator. When the system is in the series mode, due to the limited torque capacity of the generator or the limited capacity of the power battery, the generator cannot regulate the engine speed. The method provided in this alternative embodiment solves the problems of insufficient engine power output caused by insufficient generator speed regulation ability and overcharging and over-discharging of the battery during the speed regulation process due to weak battery capacity. Among them, the vehicle controller sends a speed request to the engine to adjust the operating range of the engine. In addition, the method provided in this alternative embodiment can effectively avoid the problems of insufficient engine power output caused by insufficient generator speed regulation ability and overcharging and over-discharging of the battery during the speed regulation process due to weak battery capacity.

[0061] The hybrid system of this alternative embodiment can be a dual-motor series-parallel structure. Among them, the engine and the generator achieve energy transfer through gears. When the hybrid system is running, the system detects the charging and discharging power of the power battery and the driving torque of the generator. When the charging and discharging power of the power battery and the driving torque of the generator are less than the corresponding predetermined capacity thresholds, the hybrid system enables the engine speed control function. Specifically, when the hybrid system operates in the series mode, in the series mode of the dual-motor hybrid system, the total required power of the system completely comes from the engine, and the engine itself also needs to operate in the optimal operating range. In this case, the power that the engine needs to output (equivalent to the total required power of the engine mentioned above) is equal to the superposition of the total required power of the system and the power required for the engine to adjust its own operating range. After obtaining the required output power of the engine, the optimal engine speed (equivalent to the target speed in the previous embodiment) and the operating torque (equivalent to the second torque in the previous embodiment) can be obtained according to the optimal BSFC. This optimal speed can be directly sent to the engine for execution, and the operating torque is sent to the generator for execution after speed ratio conversion.

[0062] Figure 2 It is a flowchart of another alternative vehicle speed control method according to an embodiment of the present invention. Refer to Figure 2 As shown, the vehicle speed control method includes the following steps:

[0063] S01: The HCU (Hybrid Control Unit) monitors the torque capacity of the generator and the charge and discharge capacity of the power battery in real time through CAN (Controller Area Network) signals. When the above two capabilities are less than a certain threshold, the HCU enters the engine speed control process.

[0064] It should be understood that the hybrid vehicle controller, the HCU is an actuator of the ABS (Antilock Brake System), generally composed of a boost valve (normally open valve), a pressure reducing valve (normally closed valve), a return liquid pump, and an accumulator. The boost valve and the pressure reducing valve are controlled by ECU (Electronic Control Unit) signals to realize the opening and closing of the liquid path, so as to realize the braking processes of normal, pressure maintaining, pressure reducing, and boosting. The electric pump is composed of a plunger oil pump and a drive motor, and its main function is to maintain a certain pressure of the brake fluid in the accumulator.

[0065] S02: After the HCU enters the engine speed control process, the calculation method of the total system demand power remains unchanged.

[0066] Among them, the adjustment power of the engine = PI (the optimal engine speed in the previous cycle - the actual engine speed).

[0067] It should be understood that in the case of the lack of the optimal engine speed data in the previous cycle before the current moment of the previous cycle, the adjustment power of the above engine can also be calculated based on the optimal engine speed in the vehicle controller operation cycle closest to the current moment.

[0068] S03: The total engine demand power is equal to the total system demand power plus the adjustment power of the engine.

[0069] It should be understood that the total system demand power includes the power corresponding to the throttle opening when the driver steps on the accelerator, and the additional power for vehicle accessories such as the air conditioning system, lighting system, and exhaust system.

[0070] S04: Determine the optimal engine speed in the current cycle according to the best BSFC curve. Among them, the optimal engine speed in the current cycle is the speed corresponding to the total engine demand power on the best BSFC curve.

[0071] S05: The engine executes the optimal speed in the previous step in the speed control mode.

[0072] In this alternative embodiment, the internal speed regulation of the engine is achieved through torque regulation. Torque regulation is related to the regulation processes such as intake air quantity and ignition angle regulation. According to this regulation process, it can be known that the regulation speed of the engine is slower than that of the generator. To ensure the stable control of the speed control process, it is necessary to limit the torque change speed of the generator so that the responses of the engine and the generator are in the same frequency. Among them, the generator torque can be calculated by the system torque distribution module set in the vehicle. Since it follows the driver's demand and its change rate is relatively fast, it may exceed the engine regulation ability and thus cause speed fluctuations. To avoid this problem, it is necessary to control the torque change of the generator so that it is less than or equal to the engine torque change. In addition, when the engine's own speed regulation ability is weak, it is necessary to use the generator for auxiliary regulation, but the auxiliary regulation power cannot be higher than a predetermined regulation power value. In one embodiment, the predetermined regulation power value is five kilowatts. Furthermore, it is necessary to limit the slope of the demand when calculating the total demand power of the system, and this slope cannot be greater than the response speed of the engine.

[0073] It should be noted that for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0074] Embodiment 2

[0075] According to an embodiment of the present invention, there is also provided a device for implementing the vehicle speed control method described above. Figure 3 It is a structural block diagram of an alternative vehicle speed control device according to an embodiment of the present invention. As Figure 3 shown, the data processing device includes a first acquisition module 302, a comparison module 304, a second acquisition module 306, a first determination module 308, and a second determination module 310. The following is a specific description.

[0076] A first acquisition module 302 is configured to acquire an ability parameter value for adjusting the engine speed of a hybrid vehicle in a series hybrid mode; a comparison module 304 is connected to the first acquisition module 302 and is configured to compare the ability parameter value with a predetermined ability parameter threshold to obtain a comparison result; a second acquisition module 306 is connected to the comparison module 304 and is configured to, when the comparison result indicates that the ability parameter value is less than the predetermined ability parameter threshold, acquire the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed; a first determination module 308 is connected to the second acquisition module 306 and is configured to determine the total demand power of the engine based on the vehicle demand power and the adjustment power; a second determination module 310 is connected to the first determination module 308 and is configured to determine the target speed of the engine based on the total demand power of the engine.

[0077] It should be noted here that the above first acquisition module 302, comparison module 304, second acquisition module 306, first determination module 308, and second determination module 310 respectively correspond to steps S102 to S110 in Embodiment 1. The examples and application scenarios implemented by several modules and the corresponding steps are the same, but are not limited to the content disclosed in the above Embodiment 1.

[0078] An embodiment of the present invention may provide a computer-readable storage medium. Optionally, in this embodiment, the computer-readable storage medium may be used to store the program code executed by the data processing method provided in the above Embodiment 1.

[0079] Optionally, in this embodiment, the computer-readable storage medium may be located in any one of the computer terminals in a computer terminal group in a computer network, or in any one of the mobile terminals in a mobile terminal group.

[0080] Optionally, in this embodiment, the computer-readable storage medium is set to store program code for performing the following steps: acquiring an ability parameter value for adjusting the engine speed of a hybrid vehicle in a series hybrid mode; comparing the ability parameter value with a predetermined ability parameter threshold to obtain a comparison result; when the comparison result indicates that the ability parameter value is less than the predetermined ability parameter threshold, acquiring the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the engine speed from the actual speed at the current moment to the reference speed; determining the total demand power of the engine based on the vehicle demand power and the adjustment power; determining the target speed of the engine based on the total demand power of the engine.

[0081] Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: Based on the actual rotational speed and the reference rotational speed, use the proportional-integral (PI) algorithm to determine the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed.

[0082] Optionally, the reference rotational speed is the optimal rotational speed of the engine within the target period; wherein, the optimal rotational speed of the engine within the target period is the rotational speed corresponding to the total required power of the engine within the target period.

[0083] Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: Based on the difference between the actual rotational speed and the reference rotational speed, use the proportional-integral (PI) algorithm to obtain the adjustment torque required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed; According to the adjustment torque and the actual rotational speed, obtain the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed.

[0084] Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: Obtain the correspondence relationship between the engine power and the engine rotational speed; Based on the correspondence relationship, determine the target rotational speed of the engine corresponding to the total required power of the engine.

[0085] Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: Compare the value of the ability parameter with the ability parameter threshold to obtain a comparison result, including at least one of the following: When the ability parameter value includes the torque ability parameter of the generator in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the torque ability threshold of the generator, and the torque ability parameter is less than the torque ability threshold, determine that the ability parameter value is less than the predetermined ability parameter threshold; When the ability parameter value includes the charge-discharge ability parameter of the power battery in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the charge-discharge ability threshold of the power battery, and the charge-discharge ability parameter is less than the charge-discharge ability threshold, determine that the ability parameter value is less than the predetermined ability parameter threshold.

[0086] Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: After determining the target rotational speed of the engine based on the total required power of the engine, it further includes: Obtain the first torque corresponding to the actual rotational speed of the engine at the current moment, and the second torque corresponding to the target rotational speed of the engine; Based on the first torque and the second torque, determine the first torque change corresponding to the engine; Control the second torque change corresponding to the generator in the series hybrid mode of the hybrid vehicle to be less than the first torque change.

[0087] Optionally, in this embodiment, the computer-readable storage medium is configured to store program code for performing the following steps: determining that the sum of the automotive demand power and the regulation power is the total demand power of the engine.

[0088] One of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing the relevant hardware of the terminal device through a program, and this program can be stored in a computer-readable storage medium. The storage medium may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, an optical disc, etc.

[0089] In the above embodiments of the present invention, the descriptions of the various embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0090] In the several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are merely illustrative. For example, the division of units can be a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces. The indirect coupling or communication connection of units or modules can be in an electrical or other form.

[0091] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0092] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0093] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, read-only memories (ROMs), random access memories (RAMs), mobile hard disks, magnetic disks, or optical discs.

[0094] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for controlling the rotational speed of a vehicle, characterized in that, it includes: obtaining a value of an ability parameter for adjusting the engine rotational speed in a series hybrid mode of a hybrid vehicle; comparing the value of the ability parameter with a predetermined ability parameter threshold to obtain a comparison result; when the comparison result is that the value of the ability parameter is less than the predetermined ability parameter threshold, obtaining the vehicle demand power for driving the hybrid vehicle and the adjustment power for adjusting the rotational speed of the engine from the actual rotational speed at the current moment to a reference rotational speed; determining the total demand power of the engine based on the vehicle demand power and the adjustment power; determining the target rotational speed of the engine based on the total demand power of the engine; wherein, comparing the value of the ability parameter with the ability parameter threshold to obtain a comparison result includes at least one of the following: when the value of the ability parameter includes the torque ability parameter of the generator in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the torque ability threshold of the generator, and the torque ability parameter is less than the torque ability threshold, determining that the value of the ability parameter is less than the predetermined ability parameter threshold; when the value of the ability parameter includes the charge-discharge ability parameter of the power battery in the series hybrid mode of the hybrid vehicle, the predetermined ability parameter threshold includes the charge-discharge ability threshold of the power battery, and the charge-discharge ability parameter is less than the charge-discharge ability threshold, determining that the value of the ability parameter is less than the predetermined ability parameter threshold.

2. The method according to claim 1, characterized in that, obtaining the adjustment power for adjusting the rotational speed of the engine from the actual rotational speed at the current moment to a reference rotational speed includes: based on the actual rotational speed and the reference rotational speed, using a proportional-integral (PI) algorithm to determine the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed.

3. The method according to claim 2, characterized in that, the reference rotational speed is the optimal rotational speed of the engine within a target period; wherein, the optimal rotational speed of the engine within the target period is the rotational speed corresponding to the total demand power of the engine within the target period.

4. The method according to claim 2, characterized in that, the determining the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed based on the actual rotational speed and the reference rotational speed and using a proportional-integral (PI) algorithm includes: based on the difference between the reference rotational speed and the actual rotational speed, using a proportional-integral (PI) algorithm to obtain the adjustment torque required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed; obtaining the adjustment power required to adjust the rotational speed of the engine from the actual rotational speed at the current moment to the reference rotational speed according to the adjustment torque and the actual rotational speed.

5. The method according to claim 1, characterized in that, the determining the target rotational speed of the engine based on the total demand power of the engine includes: Obtain the corresponding relationship between the engine power and the engine speed; Based on the corresponding relationship, determine the target speed of the engine corresponding to the total required power of the engine.

6. The method according to claim 1, wherein, after determining the target speed of the engine based on the total required power of the engine, further comprising: Obtain the first torque corresponding to the actual speed of the engine at the current moment, and the second torque corresponding to the target speed of the engine; Based on the first torque and the second torque, determine the first torque change corresponding to the engine; Control the second torque change corresponding to the generator of the hybrid vehicle in the series hybrid mode to be less than the first torque change.

7. The method according to any one of claims 1 to 6, wherein, the determining the total required power of the engine based on the vehicle required power and the adjustment power includes: determining the sum of the vehicle required power and the adjustment power as the total required power of the engine.

8. A speed control device for a vehicle, wherein, comprising: A first acquisition module, configured to acquire the value of the ability parameter for adjusting the speed of the engine of the hybrid vehicle in the series hybrid mode; A comparison module, configured to compare the ability parameter value with a predetermined ability parameter threshold to obtain a comparison result; A second acquisition module, configured to, when the comparison result is that the ability parameter value is less than the predetermined ability parameter threshold, acquire the vehicle required power for driving the hybrid vehicle, and the adjustment power for adjusting the speed of the engine from the actual speed at the current moment to the reference speed; A first determination module, configured to determine the total required power of the engine based on the vehicle required power and the adjustment power; A second determination module, configured to determine the target speed of the engine based on the total required power of the engine; wherein, the comparison module is further configured to determine that the ability parameter value is less than the predetermined ability parameter threshold when the ability parameter value includes the torque ability parameter of the generator of the hybrid vehicle in the series hybrid mode, the predetermined ability parameter threshold includes the torque ability threshold of the generator, and the torque ability parameter is less than the torque ability threshold; Determine that the ability parameter value is less than the predetermined ability parameter threshold when the ability parameter value includes the charge and discharge ability parameter of the power battery of the hybrid vehicle in the series hybrid mode, the predetermined ability parameter threshold includes the charge and discharge ability threshold of the power battery, and the charge and discharge ability parameter is less than the charge and discharge ability threshold.

9. A computer-readable storage medium, wherein, the storage medium includes a stored program, wherein when the program runs, it controls the device where the storage medium is located to execute the vehicle speed control method according to any one of claims 1 to 7.

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