Auxiliary braking system and method and vehicle

Abstract

The invention provides an auxiliary braking system and method and a vehicle, the system comprises a retarding device and a control device, the retarding device is arranged in a range extender of the vehicle, and an input shaft of the retarding device is connected with a crankshaft of a range extending engine in the range extender through a torque transmission device; the control device is used for obtaining the current charge state of the power battery in the process that the driving motor recovers braking energy and controlling starting and stopping of the retarding device based on the current charge state, and the retarding device is used for consuming electric energy recovered by the driving motor under driving of a range extending generator in the range extender when the retarding device is started. In the process of controlling starting and stopping of the retarding device based on the state of charge of the power battery, the electric energy recycled by the driving motor can be consumed through the retarding device under the condition that the power battery is fully charged or nearly fully charged and the like and is not suitable for receiving the recycled electric energy, so that the driving motor can be ensured to effectively recycle the braking energy; and the safety of the vehicle in the braking process is improved.

Description

Technical Field

[0001] This application relates to the field of vehicles, and particularly to an auxiliary braking system, method and vehicle. Background Art

[0002] Auxiliary braking by a retarder has significant advantages in direct-drive vehicles such as commercial vehicles and heavy machinery. Especially in long downhill, frequent braking or high-load working conditions, auxiliary braking by a retarder can effectively improve the safety of the vehicle.

[0003] Currently, traditional retarders are usually arranged on direct-drive vehicles in series or parallel to cut off or partially offset the power transmitted on the drive shaft through the retarder, thereby achieving auxiliary braking of the vehicle. However, this retarder cannot be arranged in range-extended vehicles. Therefore, when the braking energy cannot be recovered due to reasons such as a fully charged power battery, there will be a relatively high safety risk. Summary of the Invention

[0004] To solve the above technical problems, this application provides an auxiliary braking system, method and vehicle to solve the problem of relatively high safety risk in existing range-extended vehicles when the braking energy cannot be recovered due to reasons such as a fully charged power battery.

[0005] To achieve the above technical purpose, the embodiments of this application provide the following technical solutions:

[0006] In a first aspect, an embodiment of this specification provides an auxiliary braking system applied to a vehicle, the vehicle includes a range extender, the auxiliary braking system includes a retarder device and a control device, the retarder device is arranged on the range extender, and an input shaft of the retarder device is connected to a crankshaft of a range-extended engine in the range extender through a torque transmission device;

[0007] The control device is connected to the retarder device, and is configured to obtain the current state of charge of the power battery of the vehicle during the process of the drive motor of the vehicle performing braking energy recovery, and control the opening and closing of the retarder device based on the current state of charge of the power battery;

[0008] The retarder device is configured to consume the electric energy recovered by the drive motor under the drive of a range-extended generator in the range extender when it is turned on.

[0009] In one embodiment, the torque transmission device includes a first gear sleeved on the input shaft of the retarder device, and the first gear is directly or indirectly meshed with a second gear sleeved on the crankshaft;

[0010] Wherein, the speed ratio of the second gear to the first gear is less than 1:1.

[0011] In one embodiment, the drive motor is connected to the range extender and the power battery through a power conversion device, and the control device is connected to the power conversion device;

[0012] Specifically, the control device is configured to control the power conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender based on the magnitude relationship between the current state of charge of the power battery and the preset state of charge, and to control the opening and closing of the retarder.

[0013] In one embodiment, the control device is further configured to:

[0014] When controlling the retarder to be turned on, determine the target speed of the range extender generator based on the electric energy transmitted by the power conversion device to the range extender and the speed ratio between the second gear and the first gear;

[0015] Based on the target speed, control the range extender generator to rotate, and the range extender generator is configured to drive the retarder and the range extender engine to rotate through the crankshaft during rotation.

[0016] In one embodiment, the control device specifically is configured to:

[0017] Determine the candidate speed of the retarder based on the electric energy transmitted by the power conversion device to the range extender;

[0018] Determine the candidate speed of the crankshaft based on the candidate speed of the retarder and the speed ratio between the second gear and the first gear;

[0019] Determine the target speed of the range extender generator based on the candidate speed of the crankshaft and the upper and lower speed limit values of the range extender engine.

[0020] In one embodiment, the control device specifically is configured to:

[0021] Determine the lower speed limit value of the range extender engine based on the temperature of the coolant in the cooling device of the range extender engine, wherein the range extender engine is configured to drive the pumping device in the cooling device to operate during rotation.

[0022] In one embodiment, the control device specifically is configured to:

[0023] When the current state of charge of the power battery is greater than the preset state of charge, control the power conversion device to transmit at least part of the electric energy recovered by the drive motor to the range extender, and control the retarder to be turned on;

[0024] When the current state of charge of the power battery is less than or equal to the preset state of charge, control the power conversion device to transmit the electric energy recovered by the drive motor to the power battery, and control the retarder to be turned off.

[0025] In one embodiment, the control device is further configured to:

[0026] Determine the maximum recoverable electric energy of the drive motor based on the maximum consumable electric energy of the retarder and the current state of charge of the power battery;

[0027] Adjust the braking ratio between the drive motor and the mechanical braking device of the vehicle based on the maximum recoverable electric energy of the drive motor.

[0028] In a second aspect, an auxiliary braking method provided by an embodiment of this specification is applied to the auxiliary braking system as described in any one of the above. The method includes:

[0029] During the process of the drive motor of the vehicle performing braking energy recovery, obtain the current state of charge of the power battery of the vehicle;

[0030] Based on the current state of charge of the power battery, control the opening and closing of the retarder.

[0031] In a third aspect, an embodiment of this specification provides a vehicle, which includes a range extender, a drive motor, a power battery, and the auxiliary braking system as described above.

[0032] In a fourth aspect, an embodiment of this specification provides an electronic device, which includes at least one processor and at least one memory. A computer program is stored in the memory, and when the computer program is executed by the processor, the auxiliary braking method as described above is implemented.

[0033] In a fifth aspect, an embodiment of this specification provides a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, the auxiliary braking method as described above is implemented.

[0034] In a sixth aspect, an embodiment of this specification provides a computer program product or a computer program. The computer program product includes a computer program, and the computer program is stored in a computer-readable storage medium; a processor of the computer device reads the computer program from the computer-readable storage medium, and when the processor executes the computer program, the auxiliary braking method as described above is implemented.

[0035] As can be seen from the above technical solution, the embodiments of the present application provide an auxiliary braking system, method and vehicle. The system includes a retarder and a control device. The retarder is arranged in the range extender of the vehicle. The input shaft of the retarder is connected to the crankshaft of the range extender engine in the range extender through a torque transmission device. The control device is connected to the retarder and is used to obtain the current state of charge of the vehicle's power battery during the process of the driving motor of the vehicle performing braking energy recovery, and control the opening and closing of the retarder based on the current state of charge of the power battery. The retarder is used to consume the electric energy recovered by the driving motor under the drive of the range extender generator in the range extender when it is turned on. Thus, during the process of controlling the opening and closing of the retarder based on the state of charge of the power battery, when the power battery is fully charged or nearly fully charged and is not suitable for receiving recovered electric energy, the retarder can be used to consume the electric energy recovered by the driving motor, thereby ensuring that the driving motor can effectively recover braking energy and improving the safety of the vehicle during braking. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to the provided drawings.

[0037] Figure 1 FIG. is a schematic structural diagram of a retarder arranged on a direct drive vehicle in series in the prior art.

[0038] Figure 2 FIG. is a schematic structural diagram of a retarder arranged on a direct drive vehicle in parallel in the prior art.

[0039] Figure 3 FIG. is a schematic structural diagram of an auxiliary braking system provided by an embodiment of the present specification.

[0040] Figure 4 FIG. is a schematic structural diagram of another auxiliary braking system provided by an embodiment of the present specification.

[0041] Figure 5 FIG. is a schematic flowchart of an auxiliary braking method provided by an embodiment of the present specification. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of this specification shall have the ordinary meanings understood by those of ordinary skill in the art to which this specification pertains. The terms "first", "second" and similar words used in the embodiments of this specification do not denote any order, quantity or importance, but are merely set up to avoid confusion of components.

[0043] Unless the context otherwise requires, throughout this specification, "a plurality" means "at least two", and "comprising" is interpreted in an open, inclusive sense, i.e., "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "examples", "specific examples" or "some examples", etc. are intended to indicate that specific features, structures, materials or characteristics related to the embodiment or example are included in at least one embodiment or example of this specification. The schematic representations of the above terms do not necessarily refer to the same embodiment or example.

[0044] Next, the technical solutions in the embodiments of this specification will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this specification. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this specification.

[0045] Overview

[0046] As described in the background art, auxiliary braking by a retarder has significant advantages in direct-drive vehicles such as commercial vehicles and heavy machinery. For example, in buses with a vehicle length greater than 9m, trucks and special operation vehicles with a total mass ≥ 12t, etc., especially in long downhill, frequent braking or high-load working conditions, auxiliary braking by a retarder can effectively improve the safety of the vehicle.

[0047] Currently, traditional retarders are usually arranged on direct-drive vehicles in a series or parallel manner to cut off or partially offset the power transmitted on the drive shaft through the retarder, thereby achieving auxiliary braking of the vehicle. For example, as Figure 1 shown, when the retarder 103 is arranged on the direct-drive vehicle in a series manner, the retarder 103 can be arranged on the drive shaft 104 between the transmission 102 and the drive axle 105 of the vehicle. Among them, the power transmission route 106 of the vehicle can be that the power output by the engine 101 of the vehicle is transmitted to the drive axle 105 through the transmission 102 and the drive shaft 104 to drive the wheels. Thus, the retarder 103 connected in series on the drive shaft 104 can directly participate in the power transmission of the vehicle and directly transmit the braking torque to the vehicle to continuously provide stable braking force and reduce the risk of overheating failure of the service brake (brake pads). AsFigure 2 As shown in the figure, when the retarder 103 is arranged on a direct-drive vehicle in a parallel connection manner, the retarder 103 can be connected to the housing of the transmission 102 through a flange or the like. At the same time, the input shaft of the retarder 103 is connected to the output shaft of the transmission 102 through a connecting member such as a gear, so as to transmit the braking torque to the vehicle through this connecting member. Thus, the retarder 103 connected in parallel with the drive shaft 104 can partially offset the power transmitted on the drive shaft 104, so as to continuously provide stable braking force and reduce the risk of overheating failure of the service brake (brake pads).

[0048] However, in a range-extended vehicle, the range extender does not directly participate in the driving of the vehicle, resulting in the inability to arrange the retarder in the range-extended vehicle. Thus, when the braking energy cannot be recovered due to reasons such as the power battery being fully charged, there will be a relatively high safety risk.

[0049] To solve the problem that there is a relatively high safety risk in the traditional method when the braking energy cannot be recovered due to reasons such as the power battery being fully charged in a range-extended vehicle, in the technical solution of this application, an auxiliary braking system, method and vehicle are provided. The system includes a retardation device and a control device. The retardation device is arranged in the range extender of the vehicle. The input shaft of the retardation device is connected to the crankshaft of the range-extended engine in the range extender through a torque transmission device. The control device is connected to the retardation device and is used to obtain the current state of charge of the power battery of the vehicle during the process of the driving motor of the vehicle recovering braking energy, and control the opening and closing of the retardation device based on the current state of charge of the power battery. The retardation device is used to consume the electric energy recovered by the driving motor under the drive of the range-extended generator in the range extender when it is turned on. Thus, during the process of controlling the opening and closing of the retardation device based on the state of charge of the power battery, when the power battery is fully charged or nearly fully charged and not suitable for receiving the recovered electric energy, the retardation device can consume the electric energy recovered by the driving motor, thereby ensuring that the driving motor can effectively recover the braking energy and improving the safety of the vehicle during braking.

[0050] Based on the above inventive concept, the auxiliary braking system provided by the embodiments of this specification will be described exemplarily below.

[0051] Exemplary System

[0052] The embodiments of this specification provide an auxiliary braking system, which is applied to a vehicle. The vehicle includes a range extender. As Figure 3 shown, the auxiliary braking system includes a retardation device 301 and a control device ( Figure 3 the control device is not shown in the figure). The retardation device 301 is arranged in the range extender. The input shaft of the retardation device 301 ( Figure 3The input shaft of the retarder 301 is not shown in it) is connected to the crankshaft of the range extender engine 302 in the range extender through a torque transmission device 304( Figure 3 The crankshaft of the range extender engine 302 is not shown in it);

[0053] The control device is connected to the retarder 301 and is configured to obtain the current state of charge of the power battery of the vehicle during the process of the drive motor of the vehicle performing braking energy recovery, and control the opening and closing of the retarder 301 based on the current state of charge of the power battery;

[0054] The retarder 301 is configured to consume the electric energy recovered by the drive motor under the drive of the range extender generator 303 in the range extender when it is turned on.

[0055] Specifically, the vehicle can be a range-extended vehicle, that is, it includes a range extender, a power battery, and a drive motor. The range extender includes a range extender engine 302 and a range extender generator 303. The range extender engine 302 is configured to generate mechanical energy through fuel combustion and transmit the mechanical energy to the range extender generator 303 through the crankshaft of the range extender engine 302. The range extender generator 303 is configured to convert the mechanical energy generated by the range extender engine 302 into electric energy to charge the power battery with the electric energy generated by the range extender generator 303. The power battery can supply power to the drive motor to drive the vehicle to travel through the drive motor. At the same time, the drive motor can also become a generator during the braking process of the vehicle to perform braking energy recovery to achieve regenerative braking and store the recovered electric energy in the power battery. In addition, a motor torsional damper 305 can be provided in the range extender to absorb and reduce the torsional vibration generated during the power transmission process through the motor torsional damper 305. At this time, the range extender generator 303 can be directly connected to the motor torsional damper 305 through a spline shaft, and at the same time, the motor torsional damper 305 can be attached to the range extender engine 302 through a pressing device.

[0056] In implementation, the auxiliary braking system includes a retarder 301 and a control device. The retarder 301 is connected to the control device. For example, the retarder 301 can be electrically connected to the control device to control the retarder 301 through the control device. For example, the control device can control the opening and closing of the retarder 301 and can also control the retarder 301 to perform gear adjustment.

[0057] The retarder 301 can adopt a hydraulic retarder, a turbine retarder, etc., which are retarders that directly utilize the energy of the vehicle itself to work. They do not require external energy drive, have a simple structure and are easy to maintain, thus greatly reducing the cost of the auxiliary braking system and reducing the requirement for the layout space. Preferably, the retarder 301 can adopt a hydraulic retarder. The control device can be a newly added controller or an existing controller in the vehicle, such as a vehicle controller.

[0058] Among them, the input shaft of the retarder 301 is used to input torque to drive the rotation of the rotor inside the retarder 301 through the input torque. In implementation, the retarder 301 can be integrated inside the range extender. The input shaft of the retarder 301 can be connected to the crankshaft of the range extender engine 302 through the torque transmission device 304. The specific structure of the torque transmission device 304 can be set according to actual requirements. Optionally, the torque transmission device 304 can adopt a gear transmission device. For example, the torque transmission between the input shaft of the retarder 301 and the crankshaft of the range extender engine 302 is realized through the direct or indirect meshing connection between the first gear sleeved on the input shaft of the retarder 301 and the second gear 3042 sleeved on the crankshaft of the range extender engine 302. In addition, the torque transmission device 304 can also adopt a chain transmission device. For example, the torque transmission between the input shaft of the retarder 301 and the crankshaft of the range extender engine 302 is realized by connecting the first gear sleeved on the input shaft of the retarder 301 and the second gear sleeved on the crankshaft of the range extender engine 302 through a chain. It can be understood that the torque transmission device 304 can also adopt a hydraulic transmission device, that is, the mechanical energy of the crankshaft of the range extender engine 302 is converted into hydraulic energy by using a hydraulic pump and a hydraulic motor, and the hydraulic energy is converted into mechanical energy to drive the rotation of the input shaft of the retarder 301. Through this method, a large range of speed regulation of the input shaft of the retarder 301 can be achieved, but the system is complex, the cost is high, and a large space is required.

[0059] Optionally, the retarder 301 can be arranged at the upper end of the flywheel housing of the range extender engine 302, so that the space of the flywheel housing and the upper part of the range extender generator 303 can be fully utilized to arrange the retarder 301. At the same time, by setting the input shaft of the retarder 301 to be connected to the crankshaft of the range extender engine 302 through the torque transmission device 304, the axial dimension of the range extender does not need to be increased during the process of arranging the retarder 301 in the range extender, so as to adapt to the layout and matching of the retarder 301 at the vehicle end.

[0060] During implementation, when the drive motor becomes a generator for braking energy recovery, the range extender generator 303 can become a drive motor. For example, part or all of the electric energy recovered by the drive motor is used to drive the range extender generator 303 to rotate, so as to drive the crankshaft of the range extender engine 302 to rotate through the range extender generator 303, and then drive the retarder 301 and the range extender engine 302 to rotate through the crankshaft, and further consume the electric energy recovered by the drive motor through the retarder 301 and the range extender engine 302. Among them, during the rotation of the retarder 301 driven by the crankshaft, a medium (the medium of the hydraulic retarder can be oil, and the medium of the turbine retarder can be gas) flows between the rotor and the turbine to generate resistance, so as to consume the electric energy transmitted to the range extender by the electric energy conversion device. In addition, during the rotation of the range extender engine 302, frictional losses can occur to consume the electric energy recovered by the drive motor. It can be understood that during the process of consuming the electric energy recovered by the drive motor through the retarder 301 and the range extender engine 302, the retarder 301 plays a leading role.

[0061] The control device can be used to obtain the current state of charge of the power battery during the process of the drive motor of the vehicle performing braking energy recovery, and based on the current state of charge of the power battery, control the opening and closing of the retarder 301. For example, when the current state of charge of the power battery indicates that the power battery is in a fully charged or nearly fully charged state and is not suitable for receiving the electric energy recovered by the drive motor, the control device can control the retarder 301 to be turned on to consume the electric energy recovered by the drive motor through the retarder 301, so as to ensure that the drive motor can effectively recover braking energy and improve the safety of the vehicle during braking.

[0062] In addition, when the current state of charge of the power battery indicates that the power battery is in a state where it can receive the electric energy recovered by the drive motor, the control device can also control the retarder 301 to be turned off to realize the full utilization of braking energy, so as to effectively improve the cruising range of the vehicle and reduce the power consumption cost of the vehicle.

[0063] In a feasible implementation manner, as Figure 4 shown, the torque transmission device 304 includes a first gear 3041 sleeved on the input shaft of the retarder 301, and the first gear 3041 is directly or indirectly meshed with a second gear 3042 sleeved on the crankshaft;

[0064] Among them, the speed ratio of the second gear 3042 to the first gear 3041 is less than 1:1.

[0065] Specifically, the torque transmission device 304 can include a first gear 3041 sleeved on the input shaft of the retarder 301 ( Figure 4(The input shaft of the retarder 301 is not shown in the figure), that is, during the rotation of the first gear 3041, the input shaft of the retarder 301 can be driven to rotate synchronously. The second gear 3042 ([ Figure 4 (The crankshaft of the range extender engine 302 is not shown in the figure) can be a gear existing in the range extender engine 302. For example, the second gear 3042 can adopt a crankshaft timing gear. In addition, the second gear 3042 can also be a newly added gear. Among them, the second gear 3042 can rotate synchronously with the crankshaft of the range extender engine 302.

[0066] In implementation, the first gear 3041 can be directly or indirectly meshed and connected with the second gear 3042. Thus, during the rotation of the crankshaft of the range extender engine 302, the second gear 3042 can be driven to rotate synchronously, and the first gear 3041 can be driven to rotate through the second gear 3042. Furthermore, the input shaft of the retarder 301 can be driven to rotate through the first gear 3041.

[0067] Among them, Figure 4 (Only the indirect meshing connection between the first gear 3041 and the second gear 3042 is taken as an example in the figure). In implementation, the first gear 3041 can be indirectly meshed and connected with the second gear 3042 through an intermediate gear, that is, the first gear 3041 is meshed and connected with the intermediate gear, and at the same time, the intermediate gear is meshed and connected with the second gear 3042. The intermediate gear can be a gear existing in the range extender engine 302. For example, the intermediate gear can adopt an intermediate double-connected large and small gear. The intermediate double-connected large and small gear can include an intermediate double-connected large gear 3043 and an intermediate double-connected small gear 3044 connected coaxially, that is, the intermediate double-connected large gear 3043 and the intermediate double-connected small gear 3044 can rotate synchronously. The first gear 3041 can be meshed and connected with the second gear 3042 through the intermediate double-connected large gear 3043, that is, the first gear 3041 is meshed and connected with the intermediate double-connected large gear 3043, and at the same time, the intermediate double-connected large gear 3043 is meshed and connected with the second gear 3042; at the same time, the intermediate double-connected small gear 3044 can be used to drive the camshaft gear. It can be understood that the intermediate gear can also be a newly added gear, which can be specifically set according to actual requirements.

[0068] The speed ratio between the second gear 3042 and the first gear 3041 can be the ratio of the rotational speed of the second gear 3042 to the rotational speed of the first gear 3041. Preferably, the speed ratio between the second gear 3042 and the first gear 3041 can be less than 1:1, that is, during the process of driving the second gear 3042 to rotate through the crankshaft of the range extender engine 302, the rotational speed of the first gear 3041 is higher than that of the second gear 3042, so as to further reduce the structural size, weight and cost of the retarder 301, and facilitate the layout of the retarder 301 in the range extender.

[0069] It can be understood that the speed ratio of the second gear 3042 to the first gear 3041 can also be greater than or equal to 1:1, and can be specifically set according to actual requirements.

[0070] In a feasible implementation, the drive motor is connected to the range extender and the power battery through an electric energy conversion device, and the control device is connected to the electric energy conversion device;

[0071] Specifically, the control device is used for:

[0072] Based on the magnitude relationship between the current state of charge of the power battery and the preset state of charge, control the electric energy conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender, and control the opening and closing of the retarder 301.

[0073] Specifically, the drive motor can be connected to the range extender and the power battery through an electric energy conversion device, so that after the electric energy recovered by the drive motor is converted by the electric energy conversion device, it is output to the power battery and / or the range extender. At the same time, the control device can also be electrically connected to the electric energy conversion device to control the electric energy conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender through the control device.

[0074] In implementation, the control device can control the electric energy conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender according to the magnitude relationship between the current state of charge of the power battery and the preset state of charge, and at the same time, control the opening and closing of the retarder 301.

[0075] ]For example, when the control device determines, according to the magnitude relationship between the current state of charge of the power battery and the preset state of charge, that the power battery is in a state where it can receive the electric energy recovered by the drive motor, it can control the electric energy conversion device to preferentially transmit the electric energy recovered by the drive motor to the power battery and transmit the excess electric energy to the range extender, so as to realize the full utilization of braking energy, thereby effectively improving the cruising range of the vehicle and reducing the power consumption cost of the vehicle.

[0076] In addition, when the control device determines, according to the magnitude relationship between the current state of charge of the power battery and the preset state of charge, that the power battery is in a state such as full charge or near full charge and is not suitable for receiving the electric energy recovered by the drive motor, it can control the electric energy conversion device to transmit at least part of the electric energy recovered by the power battery to the range extender, so as to consume the electric energy recovered by the drive motor through the retarder 301, thereby improving the braking energy recovery ability of the drive motor.

[0077] Meanwhile, when the control device controls the power conversion device to transmit part or all of the electric energy recovered by the drive motor to the range extender, it can control the retarder 301 to turn on, so as to consume the electric energy recovered by the drive motor through the retarder 301, and ensure the braking energy recovery ability of the drive motor; in addition, when the drive motor does not perform braking energy recovery, or the electric energy transmitted by the power conversion device to the range extender is 0, the control device can control the retarder 301 to turn off, so as to ensure the normal operation of the range extender.

[0078] Thus, through the method of the embodiment of the present application, it is possible to ensure that the drive motor effectively recovers braking energy on the premise of ensuring the full utilization of braking energy, and further improve the safety of the vehicle during braking.

[0079] In a feasible implementation manner, the control device is further configured to:

[0080] When controlling the retarder 301 to turn on, determine the target speed of the range extender generator 303 based on the electric energy transmitted by the power conversion device to the range extender and the speed ratio between the second gear 3042 and the first gear 3041;

[0081] Based on the target speed, control the range extender generator 303 to rotate. The range extender generator 303 is configured to drive the retarder 301 and the range extender engine 302 to rotate through the crankshaft during rotation.

[0082] Specifically, when the control device controls the retarder 301 to turn on, it can determine the target speed of the range extender generator 303 based on the electric energy transmitted by the power conversion device to the range extender and the speed ratio between the second gear 3042 and the first gear 3041, and based on this target speed, control the range extender generator 303 to rotate, so as to drive the crankshaft of the range extender engine 302 to rotate during the rotation of the range extender generator 303, and further drive the retarder 301 and the range extender engine 302 to rotate through the crankshaft of the range extender engine 302. Among them, the speed of the range extender engine 302 can be the same as the speed of the range extender generator 303. At the same time, the ratio of the speed of the range extender generator 303 to the speed of the retarder 301 can be the speed ratio between the second gear 3042 and the first gear 3041.

[0083] In practice, the electric energy transmitted by the power conversion device to the range extender can be the electric energy that needs to be transmitted by the power conversion device to the range extender determined based on the magnitude relationship between the current state of charge of the power battery and the preset state of charge.

[0084] When the control device determines the target speed of the range extender generator 303 based on the electric energy transmitted by the electric energy conversion device to the range extender and the speed ratio between the second gear 3042 and the first gear 3041, it can determine the candidate speed of the retarder 301 based on the electric energy transmitted by the electric energy conversion device to the range extender, and determine the target speed of the range extender generator 303 based on the candidate speed of the retarder 301 and the speed ratio between the second gear 3042 and the first gear 3041, so as to ensure that the retarder 301 effectively consumes the electric energy transmitted by the electric energy conversion device to the range extender, and further improves the safety of the vehicle during braking.

[0085] In a feasible implementation manner, the control device is specifically configured to:

[0086] Determine the candidate speed of the retarder 301 based on the electric energy transmitted by the electric energy conversion device to the range extender;

[0087] Determine the candidate speed of the crankshaft based on the candidate speed of the retarder 301 and the speed ratio between the second gear 3042 and the first gear 3041;

[0088] Determine the target speed of the range extender generator 303 based on the candidate speed of the crankshaft and the upper and lower speed limits of the range extender engine 302.

[0089] Specifically, the candidate speeds of the retarder 301 may include the candidate speeds of the retarder 301 at at least two different gears. In implementation, the control device may determine the candidate speeds of the retarder 301 at each gear based on the electric energy transmitted by the electric energy conversion device to the range extender and the target correspondence relationship, and the target correspondence relationship may include the correspondence relationship between the gear, speed, and consumed electric energy of the retarder 301.

[0090] In implementation, the control device may determine the candidate speeds of the crankshaft at each gear of the retarder 301 based on the candidate speeds of the retarder 301 at each gear and the speed ratio between the second gear 3042 and the first gear 3041. Among them, for any gear of the retarder 301, the ratio of the candidate speed of the crankshaft at this gear of the retarder 301 to the candidate speed of the retarder 301 at this gear may be the speed ratio between the second gear 3042 and the first gear 3041.

[0091] Optionally, the target speed of the range extender generator 303 may be determined based on the candidate speeds of the crankshaft at each gear of the retarder 301 and the upper and lower speed limits of the range extender engine 302. It can be understood that during the operation of the range extender generator 303, the speeds of both the range extender generator 303 and the range extender engine 302 are the same as the speed of the crankshaft of the range extender engine 302.

[0092] For example, the target speed of the range extender generator 303 can be determined based on the magnitude relationship between the candidate speeds of the crankshaft of the range extender engine 302 at each gear of the retarder 301 and the upper speed limit value and the lower speed limit value of the range extender engine 302. For example, any candidate speed among the candidate speeds of the crankshaft of the range extender engine 302 at each gear of the retarder 301 that is between the upper speed limit value and the lower speed limit value of the range extender engine 302 can be used as the target speed of the range extender generator 303.

[0093] Among them, the upper speed limit value of the range extender engine 302 can be the maximum speed of the range extender engine 302 set in advance, or can also be the maximum speed of the range extender engine 302 determined according to the current state of the range extender engine 302 (such as, the fault state).

[0094] In addition, the lower speed limit value of the range extender engine 302 can be 0, or can also be determined according to the required speed of the range extender engine 302. For example, in the case where the range extender engine 302 drives the pumping device in the cooling device to operate, the required speed of the range extender engine 302 can be determined based on the coolant temperature in the pumping device, and this required speed can be used as the lower speed limit value of the range extender engine 302.

[0095] Thus, through the method of the embodiment of the present application, while ensuring that the retarder 301 effectively consumes the electric energy transmitted by the electric energy conversion device to the range extender, the safe and reliable operation of the range extender engine 302 can be ensured.

[0096] In a feasible implementation manner, the control device is specifically configured to:

[0097] Determine the lower speed limit value of the range extender engine 302 based on the coolant temperature in the cooling device of the range extender engine 302, where the range extender engine 302 is used to drive the pumping device in the cooling device to operate during rotation.

[0098] Specifically, the cooling device of the range extender engine 302 can be used to cool down the range extender engine 302, and at the same time, can also be used to cool down the retarder 301 to ensure the safe and reliable operation of the range extender engine 302 and the retarder 301. Among them, during the process of driving the retarder 301 and the range extender engine 302 to rotate by the range extender generator 303 to consume the electric energy transmitted by the electric energy conversion device to the range extender, the range extender engine 302 and the retarder 301 can be cooled by the cooling device of the range extender engine 302. Thus, the temperature of the coolant in the cooling device will rise.

[0099] In implementation, when the pumping device in the cooling device is driven by the range extender engine 302, the lower limit value of the rotational speed of the range extender engine 302 can be determined based on the temperature of the coolant in the cooling device of the range extender engine 302. Optionally, during the process of driving the retarder 301 and the range extender engine 302 to rotate by the range extender generator 303, the temperature of the coolant in the cooling device can be detected in real time by the temperature detection device, and the lower limit value of the rotational speed of the range extender engine 302 can be dynamically updated based on the temperature of the coolant. For example, the current required rotational speed of the pumping device can be determined based on the current temperature of the coolant and the target temperature of the coolant, and the current required rotational speed of the pumping device can be used as the lower limit value of the rotational speed of the range extender engine 302.

[0100] It can be understood that when the pumping device in the cooling device of the range extender engine 302 is an electric water pump, that is, there is no need to drive the pumping device to operate by the range extender engine 302, the lower limit value of the rotational speed of the range extender engine 302 can be 0. At this time, the control device can also control the operation of the pumping device based on the current required rotational speed of the pumping device to ensure that the temperature of the coolant meets the cooling requirements of the range extender engine 302 and the retarder 301, and further ensure the safe and reliable operation of the range extender engine 302 and the retarder 301 during the process of consuming the electric energy transmitted by the electric energy conversion device to the range extender by the range extender engine 302 and the retarder 301.

[0101] Thus, the retarder 301 and the range extender engine 302 can effectively consume the electric energy transmitted by the electric energy conversion device to the range extender, and further ensure that the drive motor can effectively recover the braking energy, improving the safety of the vehicle during braking.

[0102] In a feasible implementation manner, the control device is specifically configured to:

[0103] When the current state of charge of the power battery is greater than the preset state of charge, control the electric energy conversion device to transmit at least part of the electric energy recovered by the drive motor to the range extender, and control the retarder 301 to be turned on;

[0104] When the current state of charge of the power battery is less than or equal to the preset state of charge, control the electric energy conversion device to transmit the electric energy recovered by the drive motor to the power battery, and control the retarder 301 to be turned off.

[0105] Specifically, when the current state of charge of the power battery is greater than the preset state of charge, it indicates that the power battery is in a state such as fully charged or nearly fully charged, which is not suitable for receiving the electric energy recovered by the drive motor. At this time, the electric energy conversion device can be controlled to transmit at least part of the electric energy recovered by the drive motor to the range extender, and the retarder 301 can be controlled to be turned on, so that the retarder 301 rotates under the drive of the range extender generator 303 and consumes the electric energy transmitted by the electric energy conversion device to the range extender, thereby effectively ensuring the braking energy recovery ability of the drive motor and improving the safety of the vehicle during braking.

[0106] In addition, when the current state of charge of the power battery is less than or equal to the preset state of charge, it indicates that the power battery is in a state capable of receiving the electric energy recovered by the drive motor. At this time, the electric energy conversion device can be controlled to transmit the electric energy recovered by the drive motor to the power battery, and the retarder 301 can be controlled to be turned off to charge the power battery with the electric energy recovered by the drive motor, thereby enabling the full utilization of braking energy and effectively increasing the vehicle's cruising range and reducing the vehicle's electricity consumption cost.

[0107] It can be understood that when the current state of charge of the power battery is greater than the preset state of charge, the control device can also control the electric energy conversion device to feed back at least part of the electric energy recovered by the drive motor to the power grid to improve the utilization rate of the electric energy recovered by the drive motor.

[0108] At the same time, when the current state of charge of the power battery is greater than the preset state of charge, the control device can also control the electric energy conversion device to transmit at least part of the electric energy recovered by the drive motor to in-vehicle electronic devices to supply power to the in-vehicle electronic devices with the electric energy recovered by the drive motor, reduce the power consumption of the vehicle's low-voltage battery, and improve the utilization rate of the electric energy recovered by the drive motor.

[0109] In addition, a super capacitor can be set on the vehicle. When the current state of charge of the power battery is greater than the preset state of charge, the control device can also control the electric energy conversion device to transmit at least part of the electric energy recovered by the drive motor to the super capacitor to charge the super capacitor with the electric energy recovered by the drive motor. Thus, in high-power demand scenarios such as vehicle acceleration, the super capacitor can quickly release electric energy to meet the vehicle's power demand, thereby improving the vehicle's operating performance.

[0110] It should be noted that the priority of transmitting the electric energy recovered by the drive motor to the power battery is higher than that of transmitting the electric energy recovered by the drive motor to the power grid, in-vehicle electronic devices, and supercapacitors. At the same time, the priority of transmitting the electric energy recovered by the drive motor to the power grid, in-vehicle electronic devices, and supercapacitors is higher than that of transmitting the electric energy recovered by the drive motor to the range extender. Thereby, while ensuring the braking energy recovery ability of the drive motor, the utilization rate of the electric energy recovered by the drive motor can be effectively improved.

[0111] In a feasible implementation manner, the control device is further configured to:

[0112] Determine the maximum recoverable electric energy of the drive motor based on the maximum consumable electric energy of the retarder 301 and the current state of charge of the power battery;

[0113] Adjust the braking ratio between the drive motor and the mechanical braking device of the vehicle based on the maximum recoverable electric energy of the drive motor.

[0114] Specifically, the maximum consumable electric energy of the retarder 301 can be the electric energy that the retarder 301 can consume when the rotational speed of the range extender generator 303 reaches the upper limit value of the rotational speed of the range extender engine 302 and the gear of the retarder 301 is in the highest gear. Among them, the maximum consumable electric energy of the retarder 301 can be determined based on the corresponding relationship between the gear, rotational speed, and consumed electric energy of the retarder 301.

[0115] At the same time, the target charging power of the power battery can be determined based on the current state of charge of the power battery. For example, the required charging power of the power battery in the current state of charge can be determined based on the current state of charge of the power battery and the preset corresponding relationship between the state of charge of the power battery and the required charging power of the power battery, and the required charging power of the power battery in the current state of charge can be used as the target charging power of the power battery. Among them, the required charging power of the power battery can be negatively correlated with the state of charge of the power battery, that is, the lower the state of charge of the power battery, the greater its required charging power to accelerate the charging speed, and the higher the state of charge of the power battery, the smaller its required charging power to prevent overcharging of the power battery and extend the life of the power battery.

[0116] During implementation, the control device can also determine the maximum recoverable electrical energy of the drive motor based on the sum of the maximum consumable electrical energy of the retarder 301 and the target charging power of the power battery. For example, when the electrical energy recovered by the drive motor is only used for charging the power battery, the sum of the maximum consumable electrical energy of the retarder 301 and the target charging power of the power battery can be used as the maximum recoverable electrical energy of the drive motor. Additionally, based on a preset compensation value, the sum of the maximum consumable electrical energy of the retarder 301 and the target charging power of the power battery can be compensated, and the compensation result can be used as the maximum recoverable electrical energy of the drive motor.

[0117] The mechanical braking device of the vehicle can be a device that generates braking force through friction, such as brake pads or brake discs. Among them, the control device can adjust the braking ratio between the drive motor and the mechanical braking device of the vehicle based on the maximum recoverable electrical energy of the drive motor. For example, the control device can determine the braking ratio between the drive motor and the mechanical braking device according to the braking ratio distribution strategy with priority given to renewable braking based on the maximum recoverable electrical energy of the drive motor, so as to make full use of the drive motor to recover braking energy, greatly improving the safety of the vehicle during braking. In addition, the control device can also determine the braking ratio between the drive motor and the mechanical braking device based on the driving conditions of the vehicle and the maximum recoverable electrical energy of the drive motor. For example, the braking ratio corresponding to the drive motor can be positively correlated with the vehicle speed, and the electrical energy recovered by the drive motor is less than or equal to the maximum recoverable electrical energy of the drive motor, thus effectively meeting the braking requirements of the vehicle while ensuring the safety of the vehicle during braking.

[0118] Exemplary Method

[0119] In an exemplary embodiment of this specification, an auxiliary braking method is also provided, which is applied to the auxiliary braking system described in any of the above embodiments, as Figure 5 shown, the method includes:

[0120] S501. During the process of the drive motor of the vehicle recovering braking energy, obtain the current state of charge of the power battery of the vehicle;

[0121] S502. Based on the current state of charge of the power battery, control the opening and closing of the retarder 301.

[0122] In a feasible implementation manner, the controlling the opening and closing of the retarder 301 based on the current state of charge of the power battery includes:

[0123] Based on the magnitude relationship between the current state of charge of the power battery and the preset state of charge, control the power conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender, and control the opening and closing of the retarder 301.

[0124] In a feasible implementation manner, it further includes:

[0125] When controlling the retarder 301 to be turned on, based on the electric energy transmitted by the power conversion device to the range extender and the speed ratio between the second gear 3042 and the first gear 3041, determine the target speed of the range extender generator 303;

[0126] Based on the target speed, control the range extender generator 303 to rotate. The range extender generator 303 is used to drive the retarder 301 and the range extender engine 302 to rotate through the crankshaft during the rotation process.

[0127] In a feasible implementation manner, the determining the target speed of the range extender generator 303 based on the electric energy transmitted by the power conversion device to the range extender and the speed ratio between the second gear 3042 and the first gear 3041 includes:

[0128] Based on the electric energy transmitted by the power conversion device to the range extender, determine the candidate speed of the retarder 301;

[0129] Based on the candidate speed of the retarder 301 and the speed ratio between the second gear 3042 and the first gear 3041, determine the candidate speed of the crankshaft;

[0130] Based on the candidate speed of the crankshaft and the upper and lower limit values of the speed of the range extender engine 302, determine the target speed of the range extender generator 303.

[0131] In a feasible implementation manner, the determining process of the lower limit value of the speed of the range extender engine 302 includes:

[0132] Based on the temperature of the coolant in the cooling device of the range extender engine 302, determine the lower limit value of the speed of the range extender engine 302, where the range extender engine 302 is used to drive the pumping device in the cooling device to operate during the rotation process.

[0133] In a feasible implementation manner, the controlling the power conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender, and controlling the opening and closing of the retarder 301 based on the magnitude relationship between the current state of charge of the power battery and the preset state of charge includes:

[0134] When the current state of charge of the power battery is greater than the preset state of charge, control the power conversion device to transmit at least part of the electric energy recovered by the drive motor to the range extender, and control the retarder 301 to turn on;

[0135] When the current state of charge of the power battery is less than or equal to the preset state of charge, control the power conversion device to transmit the electric energy recovered by the drive motor to the power battery, and control the retarder 301 to turn off.

[0136] In a feasible implementation manner, it further includes:

[0137] Based on the maximum consumable electric energy of the retarder 30, and the current state of charge of the power battery, determine the maximum recoverable electric energy of the drive motor;

[0138] Based on the maximum recoverable electric energy of the drive motor, adjust the braking ratio between the drive motor and the mechanical braking device of the vehicle.

[0139] The auxiliary braking method provided in this embodiment belongs to the same inventive concept as the auxiliary braking system provided in the above embodiments of the present application. The control device in the auxiliary braking system can execute the auxiliary braking method provided in any of the above embodiments of the present application, and the control device has corresponding functional modules and beneficial effects for executing the auxiliary braking method. For technical details not described in detail in this embodiment, reference can be made to the specific processing content of the auxiliary braking system provided in the above embodiments of the present application, which will not be elaborated here.

[0140] Exemplary Device

[0141] In an exemplary embodiment of this specification, an electronic device is further provided. The electronic device includes at least one processor and at least one memory. A computer program is stored in the memory, and when the computer program is executed by the processor, it implements the auxiliary braking method described in any of the above implementation manners.

[0142] Exemplary vehicle

[0143] In an exemplary embodiment of this specification, a vehicle is further provided. The vehicle includes a range extender, a drive motor, a power battery, and the auxiliary braking system described in any of the above items.

[0144] Exemplary Computer Program Product and Storage Medium

[0145] In addition to the above methods and devices, the auxiliary braking method provided by the embodiments of this specification may also be a computer program product, which includes computer program instructions. When the computer program instructions are run by a processor, the processor is caused to execute the steps in the auxiliary braking methods according to various embodiments of this specification described in the "Exemplary Method" section above of this specification.

[0146] The computer program product may be written in any combination of one or more programming languages for programming code to perform the operations of the embodiments of this specification. The programming languages include object-oriented programming languages such as Java, C++, etc., and also include conventional procedural programming languages such as the "C" language or similar programming languages.

[0147] In addition, the embodiments of this specification also provide a computer-readable storage medium, on which a computer program is stored. The computer program is executed by a processor to perform the steps in the auxiliary braking methods according to various embodiments of this specification described in the "Exemplary Method" section above of this specification.

[0148] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it may include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in this specification may include non-volatile and / or volatile memories. Non-volatile memories may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0149] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, 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, it should be considered to be within the scope described in this specification.

[0150] The above-described embodiments merely represent several implementation manners of this specification. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the solutions provided by the embodiments of this specification. It should be noted that for those of ordinary skill in the art, without departing from the concept of this specification, several modifications and improvements can still be made, and these all fall within the protection scope of this specification. Therefore, the protection scope of the patent of this specification shall be subject to the appended claims.

Claims

1. An auxiliary braking system, characterized in that, Applied to a vehicle, the vehicle includes a range extender, and the auxiliary braking system includes a retarder and a control device. The retarder is arranged on the range extender, and an input shaft of the retarder is connected to a crankshaft of an extended-range engine in the range extender through a torque transmission device; The control device is connected to the retarder and is configured to obtain a current state of charge of a power battery of the vehicle during a process of braking energy recovery of a drive motor of the vehicle, and control opening and closing of the retarder based on the current state of charge of the power battery; The retarder is configured to consume electric energy recovered by the drive motor under the drive of an extended-range generator in the range extender when it is turned on.

2. The auxiliary braking system according to claim 1, wherein The torque transmission device includes a first gear sleeved on the input shaft of the retarder, and the first gear is directly or indirectly meshed and connected with a second gear sleeved on the crankshaft; Wherein, a speed ratio of the second gear to the first gear is less than 1:

1.

3. The auxiliary braking system according to claim 2, wherein The drive motor is connected to the range extender and the power battery through an electric energy conversion device, and the control device is connected to the electric energy conversion device; The control device is specifically configured to control the electric energy conversion device to transmit the electric energy recovered by the drive motor to the power battery and / or the range extender based on a magnitude relationship between the current state of charge of the power battery and a preset state of charge, and control opening and closing of the retarder.

4. The auxiliary braking system according to claim 3, wherein, The control device is further configured to: When controlling the retarder to be turned on, determine a target speed of the extended-range generator based on the electric energy transmitted to the range extender by the electric energy conversion device and the speed ratio of the second gear to the first gear; Based on the target speed, control the extended-range generator to rotate, and the extended-range generator is configured to drive the retarder and the extended-range engine to rotate through the crankshaft during rotation.

5. The auxiliary braking system according to claim 4, characterized in that, The control device is specifically configured to: Determine a candidate speed of the retarder based on the electric energy transmitted to the range extender by the electric energy conversion device; Determine a candidate speed of the crankshaft based on the candidate speed of the retarder and the speed ratio of the second gear to the first gear; Determine the target speed of the extended-range generator based on the candidate speed of the crankshaft and an upper limit value and a lower limit value of the speed of the extended-range engine.

6. The auxiliary braking system according to claim 5, characterized in that The control device is specifically configured to: Determine the lower limit value of the speed of the extended-range engine based on a coolant temperature in a cooling device of the extended-range engine, wherein the extended-range engine is configured to drive a pumping device in the cooling device to operate during rotation.

7. The auxiliary braking system according to claim 3, wherein The control device is specifically configured to: When the current state of charge of the power battery is greater than the preset state of charge, control the electric energy conversion device to transmit at least part of the electric energy recovered by the drive motor to the range extender, and control the retarder to be turned on; When the current state of charge of the power battery is less than or equal to the preset state of charge, control the electric energy conversion device to transmit the electric energy recovered by the drive motor to the power battery, and control the retarder to be turned off.

8. The auxiliary braking system according to any one of claims 1 to 7, characterized in that, The control device is further configured to: Determine the maximum recoverable electric energy of the drive motor based on the maximum consumable electric energy of the retarder and the current state of charge of the power battery. Adjust the braking ratio of the drive motor and the mechanical braking device of the vehicle based on the maximum recoverable electric energy of the drive motor.

9. An auxiliary braking method, characterized in that, Applied to the auxiliary braking system according to any one of claims 1 to 8, the method includes: During the process of the drive motor of the vehicle recovering braking energy, obtain the current state of charge of the power battery of the vehicle. Control the opening and closing of the retarder based on the current state of charge of the power battery.

10. A vehicle, characterized in that, The vehicle includes a range extender, a drive motor, a power battery, and the auxiliary braking system according to any one of claims 1 to 8.

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