Exhaust brake control methods, systems, computing devices, storage media, and vehicles

Abstract

This specification discloses an exhaust braking control method, system, computing device, storage medium, and vehicle. In this method, when a hybrid vehicle is operating on a long downhill slope and the generator set enters a power-consuming state, the engine is put into in-cylinder braking or exhaust braking mode, and the generator is in speed mode. In the control of the generator's target speed, a torque limit calculated by mechanical power is added. This torque limit restricts the integral part of the speed loop and the proportional-integral sum in the generator control, improving the power response of the generator's exhaust braking and avoiding excessive overshoot. By having the generator drive the engine to consume excess feedback energy, the battery charge can be dynamically adjusted, ensuring that the feedback energy generated during drive auxiliary braking does not lead to overcharging, and also ensuring the auxiliary braking of the drive motor, thereby improving vehicle driving safety.

Description

Technical Field

[0001] This invention relates to the field of IPU motor controller technology for new energy vehicles, and more specifically, to an exhaust braking control method, system, computing device, storage medium, and vehicle. Background Technology

[0002] Heavy-duty hybrid trucks using a series hybrid system require a high-power generator set. This generator set consists of a diesel engine and a generator. The engine is controlled by an engine controller (ECU), and the generator is controlled by a generator controller (GCU). The controller coordinating the operation of the generator and engine is the range extender controller (RCU). IPU stands for Intelligent Power Unit, and the IPU motor controller integrates the functions of the range extender coordinating controller (RCU) and the generator controller (GCU) in a new energy vehicle range extender.

[0003] In the use of hybrid electric vehicles, there is a common operating condition: when the vehicle is on a long downhill section, the slope can be tens of kilometers long. In existing technology, when the vehicle is on a long downhill section, the drive motor operates in regenerative braking mode to provide braking force, preventing brake pads from failing due to prolonged use. Simultaneously, the vehicle's kinetic energy is converted into electrical energy and stored in the vehicle's battery. However, after a period of operation, the energy regenerated by the drive motor will fully charge the battery. If the drive motor is not used for braking at this point, only mechanical braking can be achieved, potentially leading to brake failure; if the drive motor is used for braking at this point, it will cause the battery to overcharge.

[0004] Therefore, there is an urgent need to study a control method and system to solve the problems arising during regenerative braking of automobiles and improve vehicle driving safety. Summary of the Invention

[0005] This specification provides an exhaust braking control method, system, computing device, storage medium, and vehicle to overcome at least one technical problem existing in the related art.

[0006] According to a first aspect of the embodiments of this specification, a hybrid vehicle exhaust braking control method is provided, comprising: when the generator set of a hybrid vehicle enters a power consumption state, acquiring the target power consumption required to be provided by the generator set in the power consumption state; obtaining the target speed of the generator set by looking up a table through a pre-obtained generator set power-speed curve based on the target power consumption; acquiring the mechanical power required to be provided by the generator in the power consumption state based on the target power consumption and a preset electromechanical conversion efficiency; calculating a first torque value of the generator based on the acquired actual generator speed and the mechanical power; using a preset peak torque of the generator as a second torque value, the second torque value being determined by the configuration of the generator set; using the minimum value between the first torque value and the second torque value as a torque limit value of the generator set; controlling the engine to stop fuel injection and enter an exhaust braking / cylinder braking mode, causing the generator to operate in a speed mode, the target speed of the speed mode being executed according to the target speed, the speed loop of the speed mode being implemented by a PI controller; and controlling the generator torque to not exceed the torque limit value according to the torque limit value.

[0007] Optionally, the step of obtaining the mechanical power required by the generator under power consumption state based on the target power consumption and the preset electromechanical conversion efficiency, calculating the first torque value of the generator based on the obtained actual generator speed and the mechanical power, using the preset generator peak torque as the second torque value, the second torque value being determined by the configuration of the generator set, and using the minimum value between the first torque value and the second torque value as the torque limit value of the generator set, includes:

[0008] Based on the target power consumption and the preset electromechanical conversion efficiency, the mechanical power required by the generator under power consumption conditions is obtained, and the mechanical power is calculated according to the following formula:

[0009] PwrMech=PwrCmd*FacEff

[0010] In the formula, PwrCmd is the target power consumption, FacEff is the electromechanical conversion efficiency, and PwrMech is the mechanical power.

[0011] The first torque value of the generator is calculated based on the actual generator speed and the mechanical power, and is obtained according to the following formula:

[0012]

[0013] In the formula, PwrMech is the mechanical power, nAct is the actual speed of the generator, and TrqLmt is the first torque value;

[0014] The preset peak torque of the generator is used as the second torque value, which is determined by the configuration of the generator set.

[0015] The minimum value between the first torque value and the second torque value is taken as the torque limit value of the generator set, and the torque limit value is obtained according to the following formula:

[0016] MinTrqLmt=MIN(TrqMax,TrqLmt)

[0017] In the formula, TrqLmt is the first torque value, TrqMax is the second torque value, and MinTrqLmt is the torque limit value.

[0018] Optionally, the speed loop of the speed mode is implemented with a PI controller. The step of controlling the generator torque to not exceed the torque limit value according to the torque limit value includes: in the PI control, the integral part of the speed loop is limited by the torque limit value, and the proportional integral of the speed loop is limited by the torque limit value.

[0019] Optionally, the electromechanical conversion efficiency is set to 90%.

[0020] According to a second aspect of the embodiments of this specification, a hybrid exhaust braking control system is provided, including a speed acquisition module, a torque acquisition module, and a speed control module. The speed acquisition module is configured to, when the generator set of a hybrid vehicle enters a power-consuming state, acquire the target power consumption required by the generator set in the power-consuming state, and obtain the target speed of the generator set by looking up a table using a pre-obtained generator set power-speed curve based on the target power consumption. The torque acquisition module is configured to, based on the target power consumption and a preset electromechanical conversion efficiency, obtain the mechanical power required by the generator in the power-consuming state, calculate a first torque value of the generator based on the acquired actual generator speed and the mechanical power, use a preset peak torque of the generator as a second torque value, the second torque value being determined by the configuration of the generator set, and use the minimum value between the first torque value and the second torque value as a torque limit value of the generator set. The speed control module is configured to control the engine to stop fuel injection and enter an exhaust braking / cylinder braking mode, causing the generator to operate in a speed mode, the target speed of the speed mode being executed according to the target speed, the speed loop of the speed mode being implemented by a PI controller, and controlling the generator torque to not exceed the torque limit value according to the torque limit value.

[0021] Optionally, the torque acquisition module includes a mechanical power calculation unit and a torque calculation unit, wherein...

[0022] The mechanical power calculation unit is configured to obtain the mechanical power required by the generator under power consumption conditions based on the target power consumption and a preset electromechanical conversion efficiency, and calculate the mechanical power according to the following formula:

[0023] PwrMech=PwrCmd*FacEff

[0024] In the formula, PwrCmd is the target power consumption, FacEff is the electromechanical conversion efficiency, and PwrMech is the mechanical power.

[0025] The torque calculation unit is configured to calculate a first torque value of the generator based on the acquired actual generator speed and the mechanical power, and obtain the first torque value according to the following formula:

[0026]

[0027] In the formula, PwrMech is the mechanical power, nAct is the actual speed of the generator, and TrqLmt is the first torque value;

[0028] The preset peak torque of the generator is used as the second torque value, which is determined by the configuration of the generator set.

[0029] The minimum value between the first torque value and the second torque value is taken as the torque limit value of the generator set, and the torque limit value is obtained according to the following formula:

[0030] MinTrqLmt=MIN(TrqMax,TrqLmt)

[0031] In the formula, TrqLmt is the first torque value, TrqMax is the second torque value, and MinTrqLmt is the torque limit value.

[0032] Optionally, in the speed control module, in PI control, the integral part of the speed loop is limited by the torque limit value, and the proportional-integral sum of the speed loop is limited by the torque limit value.

[0033] According to a third aspect of the embodiments of this specification, a computing device is provided, including a storage device and a processor, the storage device being used to store a computer program, and the processor running the computer program to cause the computing device to perform the steps of the hybrid exhaust brake control method.

[0034] According to a fourth aspect of the embodiments of this specification, a storage medium is provided that stores a computer program used in the computing device, which, when executed by a processor, implements the steps of the hybrid exhaust braking control method.

[0035] According to a fifth aspect of the embodiments of this specification, a vehicle is provided, including the aforementioned hybrid exhaust brake control system.

[0036] The beneficial effects of the embodiments in this specification are as follows:

[0037] This specification provides an exhaust braking control method, system, computing device, storage medium, and vehicle. When a vehicle is on a long downhill section, and the drive motor is charging the battery to near full capacity in regenerative braking mode, the engine is put into exhaust braking mode to rapidly consume the battery's charge, thereby reducing the battery's state of charge (SOC) in real time. This simultaneously consumes the regenerative energy generated by the drive motor due to energy feedback, ensuring that the drive motor can assist braking while preventing battery overcharging. This method operates the engine in in-cylinder braking or exhaust braking mode, and the generator in speed mode. In controlling the generator's target speed, a torque limit calculated by mechanical power is added. This torque limit restricts the integral part of the speed loop and the proportional-integral sum in the generator control, ensuring that the generator system's power consumption reaches the target power and then no longer increases torque, improving the generator's exhaust braking power response rate. Compared to existing technologies, this method uses the generator to drive the engine to consume excess regenerative energy, dynamically adjusting the battery charge and ensuring that the regenerative energy generated during drive-assisted braking does not lead to overcharging, thus improving the safety and reliability of the vehicle when driving on long downhill sections.

[0038] The innovative aspects of the embodiments in this specification include:

[0039] 1. In this specification, when the vehicle is on a long downhill road, and the energy fed back by the drive motor is about to fully charge or nearly fully charge the battery, it is still desirable to use the energy feedback from the drive motor to assist braking. Through the vehicle's IPU controller-generator-engine range extender system, the engine intake and exhaust braking conditions are activated. Under these conditions, the battery charge is rapidly consumed, thereby simultaneously consuming the feedback energy generated by the drive motor due to energy feedback. The battery charge can be dynamically adjusted to ensure that the feedback energy generated during drive-assisted braking does not lead to overcharging. This is one of the innovative points of the embodiments in this specification.

[0040] 2. The method and design for calculating the mechanical power required by the generator system and determining the torque limit at the current speed in this specification is one of the innovative points of the embodiments in this specification.

[0041] 3. In this specification, the proportional-integral sum of the speed loop of the generator system is limited by torque limitation, thereby dynamically maintaining the actual exhaust braking power of the generator set equal to the target power consumption within the error range during the speed regulation process of the generator exhaust braking, thus improving the power response of the generator exhaust braking; limiting the integral part of the speed loop of the generator system by torque limitation reduces the degree of integral oversaturation of the speed loop of the generator system and improves the speed of integral desaturation, which is one of the innovative points of the embodiments of this specification. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments or related technologies of this specification, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 A schematic flowchart of a hybrid exhaust braking control method provided in the embodiments of this specification;

[0044] Figure 2 This is a schematic diagram of a hybrid exhaust braking control system provided in an embodiment of this specification;

[0045] Figure 3 This is a schematic diagram of the structure of a computing device provided in an embodiment of this specification;

[0046] Figure 4 This is a schematic diagram of the structure of a storage medium provided in an embodiment of this specification. Detailed Implementation

[0047] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] It should be noted that the terms "comprising" and "having," and any variations thereof, in the embodiments and drawings of this specification are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0049] This specification discloses an exhaust braking control method, system, computing device, storage medium, and vehicle, which will be described in detail below.

[0050] When a vehicle is on a long downhill section, a regenerative braking method is adopted, where the drive motor controls the generator set to drive the diesel engine. The diesel engine is in exhaust braking or in-cylinder braking mode. By keeping the generator in speed mode, the engine is dragged to the corresponding speed, so that the power consumption of the generator set and the regenerative braking power generation of the drive motor are equal, thereby consuming electrical energy and allowing the vehicle to use the drive motor to assist braking for an extended period of time. Furthermore, considering that when the diesel engine is a high-power, high-inertia system, it takes a particularly long time for the generator to drag the engine to the corresponding speed in speed mode, this specification provides a hybrid exhaust braking control method to solve the problem of regenerative energy consumption when a vehicle is on a long downhill section.

[0051] Figure 1 This is a schematic flowchart illustrating a hybrid power exhaust braking control method provided in an embodiment of this specification. Figure 1 As shown, a hybrid power exhaust braking control method includes:

[0052] S110. When the generator set of the hybrid vehicle enters the power consumption state, obtain the target power consumption that the generator set needs to provide in the power consumption state, and obtain the target speed of the generator set by looking up a table through the pre-obtained generator set power-speed curve based on the target power consumption.

[0053] When a diesel engine performs in-cylinder braking or exhaust braking, the engine provides resistance, and the resistance is constant at each speed. For example, the resistance at 1800 rpm is 1000 Nm. Therefore, when the engine speed is 1800 rpm and exhaust braking is performed, the resistance must be 1000 Nm.

[0054] Based on this, the corresponding curve of the power consumption control of the engine and the engine speed (Engine_nPwr2SpdCUR) can be calibrated at each steady-state speed, that is, the power-speed curve of the generator set.

[0055] After the generator set enters the power consumption state, the target speed nCmd of the generator is obtained by looking up the target power (PwrCmd) on the generator set exhaust brake power-speed curve (Engine_nEBPwr2SpdCUR).

[0056] S120. Based on the target power consumption and the preset electromechanical conversion efficiency, the mechanical power that the generator needs to provide under power consumption conditions is obtained. The first torque value of the generator is calculated based on the actual speed of the generator and the mechanical power. The preset peak torque of the generator is used as the second torque value. The second torque value is determined by the configuration of the generator set. The minimum value between the first torque value and the second torque value is used as the torque limit value of the generator set.

[0057] Estimate the mechanical power that the generator should provide, because when the generator is working, it is in electric mode, and the electrical power of the generator system consisting of the generator and controller is greater than the mechanical power. Therefore, it is necessary to estimate the mechanical power of the generator.

[0058] In a specific implementation, step S120, which involves obtaining the mechanical power required by the generator under power consumption conditions based on the target power consumption and a preset electromechanical conversion efficiency, calculating a first torque value of the generator based on the actual generator speed and the mechanical power, using a preset peak torque of the generator as a second torque value (the second torque value is determined by the configuration of the generator set), and using the minimum value between the first torque value and the second torque value as the torque limit value of the generator set, includes:

[0059] Based on the target power consumption and the preset electromechanical conversion efficiency, the mechanical power required by the generator under power consumption conditions is obtained, and the mechanical power is calculated according to the following formula:

[0060] PwrMech=PwrCmd*FacEff

[0061] In the formula, PwrCmd is the target power consumption, FacEff is the electromechanical conversion efficiency, and PwrMech is the mechanical power.

[0062] 9550 is a constant.

[0063] Because the power accuracy requirements for exhaust braking are not particularly high, an error within ±5% is generally acceptable. Therefore, adjusting the calibration value FacEff used for calculation is sufficient to achieve a good result within 5%. The electromechanical conversion efficiency can be taken as 90%.

[0064] The first torque value of the generator is calculated based on the actual generator speed and the mechanical power, and is obtained according to the following formula:

[0065]

[0066] In the formula, PwrMech is the mechanical power, nAct is the actual speed of the generator, and TrqLmt is the first torque value.

[0067] The preset peak torque of the generator is used as the second torque value, which is determined by the configuration of the generator set.

[0068] Since the generator itself has a maximum torque (TrqMax), the smaller value between the maximum torque and the calculated torque value (TrqLmt) is taken to obtain the minimum torque limit value.

[0069] The minimum value between the first torque value and the second torque value is taken as the torque limit value of the generator set, and the torque limit value is obtained according to the following formula:

[0070] MinTrqLmt=MIN(TrqMax,TrqLmt)

[0071] In the formula, TrqLmt is the first torque value, TrqMax is the second torque value, and MinTrqLmt is the torque limit value.

[0072] S130, Control the engine to stop fuel injection and enter the exhaust braking / cylinder braking mode, make the generator work in speed mode, the target speed of the speed mode is executed according to the target speed, the speed loop of the speed mode is implemented by a PI controller, and control the generator torque to not exceed the torque limit value according to the torque limit value.

[0073] In speed mode, a proportional-integral (PI) controller is used for control. To improve response speed, the proportional factor (Kp) and integral factor (Ki) need to be increased. However, an excessively large proportional factor leads to increased overshoot, and an excessively large integral factor leads to increased static error. The resistance at the target speed corresponding to the engine's exhaust braking target power is often less than the motor's peak torque. During the process of the motor reaching the target speed, and during the generator speed adjustment process, especially for systems with large inertia, the motor's speed loop PI controller will quickly pull the motor torque to its peak value in order to reach the target speed as soon as possible. However, when the generator operates at peak torque, the power consumption generated may exceed the target power, resulting in overshoot, especially for systems with large inertia, where overshoot may even be several times. Therefore, it is necessary to limit the generator torque using the aforementioned torque limit value.

[0074] The engine stops injecting fuel and operates in exhaust braking mode / in-cylinder braking mode, depending on the engine's configuration. The generator operates in speed mode, and the target speed is executed according to the target speed (nCmd) obtained in S110. The generator system uses a proportional-integral (PI) controller to control the speed loop.

[0075] In a specific implementation, the speed loop of the speed mode is implemented using a PI controller. The step of controlling the generator torque to not exceed the torque limit value includes:

[0076] In PI control, the integral portion of the speed loop is limited by the torque limit value, and the proportional-integral sum of the speed loop is also limited by the torque limit value.

[0077] The goal of generator set exhaust braking is to consume a certain amount of power. However, the power consumption is obtained by dragging the generator to the target speed. If a large inertia system is encountered, in order to quickly respond to the target speed, power overshoot will occur.

[0078] This method calculates the motor torque based on the estimated mechanical power of the motor, which can maintain the power consumption near the target power consumption during the speed adjustment process, thus achieving a rapid response effect.

[0079] The generator speed loop integral (TrqI) and proportional-integral sum (TrqPI) are limited simultaneously by the motor torque limit value. Wherein:

[0080] The limit proportional-integral sum (TrqPI) is used to limit the output so that the actual power and the target power are equal within the error range during the speed regulation process, and finally reach the steady-state speed and steady-state power.

[0081] Limiting the integral component (TrqPI) is crucial because in the control of large inertia systems, if the integral component is not limited, or if the integral component is limited by the peak torque (TrqMax), then during speed regulation, if an error persists in the speed loop, the integral component will continuously accumulate, leading to integral oversaturation. When the target speed changes, the integral desaturation is very slow, resulting in a slow system response. Therefore, to prevent integral oversaturation, the integral is limited by a calculated torque limit value, MinTrqLmt, which improves the speed regulation response rate of the controller.

[0082] The control of the target speed incorporates a torque limiting function based on mechanical power calculation, ensuring that the power consumption of the generator system reaches the target power and then the torque is no longer increased. Although this results in a slower speed response of the generator system, the actual power consumption response is greatly improved.

[0083] According to actual tests, without using this method, the same PI controller with the same control parameters (same proportional coefficient and integral coefficient) takes more than 10 seconds to reach the same target power and target steady-state speed; while with the results of using this patent, although the response to reach the target speed takes more than 20 seconds, the actual power response can be completed within 100ms.

[0084] In this embodiment, the exhaust braking control method improves the power response rate, enabling both rapid response and avoiding power overshoot.

[0085] Figure 2 This is a schematic diagram of a hybrid exhaust braking control system provided as an embodiment of this specification. Figure 2As shown, a hybrid exhaust braking control system 200 includes a speed acquisition module 210, a torque acquisition module 220, and a speed control module 230, wherein...

[0086] The speed acquisition module 210 is configured to acquire the target power consumption required by the generator set in the power consumption state when the generator set of the hybrid vehicle enters the power consumption state, and obtain the target speed of the generator set by looking up a table based on the target power consumption power through a pre-obtained generator set power-speed curve.

[0087] The torque acquisition module 220 is configured to obtain the mechanical power that the generator needs to provide in the power consumption state based on the target power consumption and the preset electromechanical conversion efficiency, calculate the first torque value of the generator based on the actual speed of the generator and the mechanical power, take the preset peak torque of the generator as the second torque value, the second torque value is determined by the configuration of the generator set, and take the minimum value between the first torque value and the second torque value as the torque limit value of the generator set.

[0088] In a specific implementation, the torque acquisition module 220 includes a mechanical power calculation unit 2202 and a torque calculation unit 2204, wherein...

[0089] The mechanical power calculation unit 2202 is configured to obtain the mechanical power required by the generator under power consumption conditions based on the target power consumption and the preset electromechanical conversion efficiency, and calculate the mechanical power according to the following formula:

[0090] PwrMech=PwrCmd*FacEff

[0091] In the formula, PwrCmd is the target power consumption, FacEff is the electromechanical conversion efficiency, and PwrMech is the mechanical power.

[0092] The torque calculation unit 2204 is configured to calculate a first torque value of the generator based on the acquired actual generator speed and the mechanical power, and obtain the first torque value according to the following formula:

[0093]

[0094] In the formula, PwrMech is the mechanical power, nAct is the actual speed of the generator, and TrqLmt is the first torque value.

[0095] The preset peak torque of the generator is used as the second torque value, which is determined by the configuration of the generator set.

[0096] The minimum value between the first torque value and the second torque value is taken as the torque limit value of the generator set, and the torque limit value is obtained according to the following formula:

[0097] MinTrqLmt=MIN(TrqMax,TrqLmt)

[0098] In the formula, TrqLmt is the first torque value, TrqMax is the second torque value, and MinTrqLmt is the torque limit value.

[0099] The speed control module 230 is configured to control the engine to stop fuel injection and enter the exhaust braking / cylinder braking mode, so that the generator operates in speed mode. The target speed of the speed mode is executed according to the target speed. The speed loop of the speed mode is implemented by a PI controller. According to the torque limit value, the generator torque is controlled to not exceed the torque limit value.

[0100] In specific implementation, in the speed control module 230, in PI control, the integral part of the speed loop is limited by the torque limit value, and the proportional-integral sum of the speed loop is also limited by the torque limit value.

[0101] Figure 3 This is a schematic diagram of the structure of a computing device provided as an embodiment of this specification. Figure 3 As shown, a computing device 300 includes a storage device 310 and a processor 320. The storage device 310 stores a computer program, and the processor 320 runs the computer program to cause the computing device 300 to perform the steps of the hybrid exhaust braking control method.

[0102] Figure 4 This is a schematic diagram of the structure of a storage medium provided in an embodiment of this specification. For example... Figure 4 As shown, a storage medium 400 stores a computer program 410 used in the computing device, which, when executed by a processor, implements the steps of the hybrid exhaust braking control method.

[0103] This specification provides an embodiment of a vehicle including the aforementioned hybrid exhaust brake control system.

[0104] In summary, the embodiments of this specification provide an exhaust braking control method, system, computing device, storage medium, and vehicle. When the engine is under in-cylinder braking or exhaust braking conditions, the generator is controlled to be in speed mode. In the control of the generator's target speed, a torque limit calculated by mechanical power is added. The torque limit restricts the proportional-integral sum of the speed loop in the generator control. By limiting the integral part of the speed loop through the torque limit, excessive overshoot can be avoided, improving the power response of the generator's exhaust braking. The battery charge can be dynamically adjusted, ensuring that the feedback energy generated during drive auxiliary braking does not lead to overcharging, and ensuring the auxiliary braking of the drive motor, thereby improving the safety of vehicle driving.

[0105] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0106] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hybrid exhaust brake control method characterized by, Comprise: In the case that the generator set of the hybrid vehicle enters the power consumption state, the target power consumption power required to be provided by the generator set in the power consumption state is obtained, and the target speed of the generator set is obtained by looking up the pre-obtained power-speed curve of the generator set according to the target power consumption power; According to the target power consumption power and the preset electromechanical conversion efficiency, the mechanical power required to be provided by the generator in the power consumption state is obtained, the first torque value of the generator is calculated according to the obtained actual speed of the generator and the mechanical power, the preset peak torque of the generator is taken as the second torque value, the second torque value is determined by the configuration of the generator set, and the minimum value of the first torque value and the second torque value is taken as the torque limit value of the generator set; The engine is controlled to stop fuel injection and enter the exhaust brake / in-cylinder brake mode, the generator is controlled to work in the speed mode, the target speed of the speed mode is executed according to the target speed, the speed loop of the speed mode is realized by a PI controller, and the generator torque is controlled to be less than the torque limit value according to the torque limit value.

2. The method of claim 1, wherein, The step of obtaining the mechanical power required to be provided by the generator in the power consumption state according to the target power consumption power and the preset electromechanical conversion efficiency, calculating the first torque value of the generator according to the obtained actual speed of the generator and the mechanical power, taking the preset peak torque of the generator as the second torque value, and determining the second torque value according to the configuration of the generator set, and taking the minimum value of the first torque value and the second torque value as the torque limit value of the generator set, comprises: According to the target power consumption power and the preset electromechanical conversion efficiency, the mechanical power required to be provided by the generator in the power consumption state is obtained, and the mechanical power is calculated according to the following formula: PwrMech=PwrCmd*FacEff In the formula, PwrCmd is the target power consumption power, FacEff is the electromechanical conversion efficiency, and PwrMech is the mechanical power; The first torque value of the generator is calculated according to the obtained actual speed of the generator and the mechanical power, and the first torque value is obtained according to the following formula: In the formula, PwrMech is the mechanical power, nAct is the actual speed of the generator, and TrqLmt is the first torque value; The preset peak torque of the generator is taken as the second torque value, and the second torque value is determined according to the configuration of the generator set; The minimum value of the first torque value and the second torque value is taken as the torque limit value of the generator set, and the torque limit value is obtained according to the following formula: MinTrqLmt=MIN(TrqMax,TrqLmt) In the formula, TrqLmt is the first torque value, TrqMax is the second torque value, and MinTrqLmt is the torque limit value.

3. The method of claim 1, wherein, The step of realizing the speed loop of the speed mode by a PI controller and controlling the generator torque to be less than the torque limit value according to the torque limit value, comprises: In the PI control, the integral part of the speed loop is limited by the torque limit value, and the proportional and integral of the speed loop are limited by the torque limit value.

4. The method of claim 1, wherein, The electromechanical conversion efficiency is 90%.

5. A hybrid exhaust brake control system characterized by, Comprise a speed obtaining module, a torque obtaining module and a speed control module, wherein The rotating speed obtaining module is configured to obtain a target power consumption in the power consumption state of the generator set, and obtain a target rotating speed of the generator set according to the target power consumption and a pre-obtained power-rotating speed curve of the generator set, when the generator set of the hybrid vehicle enters the power consumption state; The torque obtaining module is configured to obtain a mechanical power required to be provided by the generator in the power consumption state according to the target power consumption and a preset electromechanical conversion efficiency, calculate a first torque value of the generator according to the actual rotating speed of the generator and the mechanical power, take a preset peak torque of the generator as a second torque value, the second torque value being determined by the configuration of the generator set, and take the minimum value between the first torque value and the second torque value as a torque limit value of the generator set. The speed control module is configured to control the engine to stop fuel injection and enter an exhaust brake / in-cylinder brake mode, control the generator to work in a speed mode, execute the target speed of the speed mode according to the target rotating speed, realize a speed loop of the speed mode by a PI controller, and control the generator torque to be less than the torque limit value according to the torque limit value.

6. The system of claim 5, wherein, The torque obtaining module includes a mechanical power calculation unit and a torque calculation unit, wherein The mechanical power calculation unit is configured to obtain the mechanical power required to be provided by the generator in the power consumption state according to the target power consumption and the preset electromechanical conversion efficiency, and calculate the mechanical power according to the following formula: PwrMech=PwrCmd*FacEff In the formula, PwrCmd is the target power consumption, FacEff is the electromechanical conversion efficiency, and PwrMech is the mechanical power. The torque calculation unit is configured to calculate the first torque value of the generator according to the actual rotating speed of the generator and the mechanical power, and obtain the first torque value according to the following formula: In the formula, PwrMech is the mechanical power, nAct is the actual rotating speed of the generator, and TrqLmt is the first torque value. The preset peak torque of the generator is taken as the second torque value, and the second torque value is determined by the configuration of the generator set. The minimum value between the first torque value and the second torque value is taken as the torque limit value of the generator set, and the torque limit value is obtained according to the following formula: MinTrqLmt=MIN(TrqMax,TrqLmt) In the formula, TrqLmt is the first torque value, TrqMax is the second torque value, and MinTrqLmt is the torque limit value.

7. The system of claim 5, wherein, In the speed control module, In the PI control, the integral part of the speed loop is limited by the torque limit value, and the proportional integral part of the speed loop is limited by the torque limit value.

8. A computing device, comprising: The computing device includes a storage device and a processor, the storage device is used to store a computer program, and the processor runs the computer program to make the computing device execute the steps of the method in any one of claims 1-4.

9. A storage medium, characterized by The computer program used in the computing device in claim 8 is stored, and the computer program is executed by the processor to realize the steps of the method in any one of claims 1-4.

10. A vehicle characterized by comprising: A hybrid exhaust brake control system including any of claims 5-7.

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