WO2024001873A1

WO2024001873A1 - Gear shifting method and system based on hybrid power system

Info

Publication number: WO2024001873A1
Application number: PCT/CN2023/101394
Authority: WO
Inventors: 尹建坤; 马艳红; 刘建康; 郭丁伊
Original assignee: 中国第一汽车股份有限公司
Priority date: 2022-06-27
Filing date: 2023-06-20
Publication date: 2024-01-04
Also published as: CN115285107A

Abstract

A gear shifting method and system based on a hybrid power system. The method comprises: a vehicle hybrid control unit sets threshold value parameters of a battery charge state of a battery charge state module, wherein the threshold value parameters at least comprise a start threshold value SOCEngSt, a stop threshold value SOCEngStp, a reverse gear lower limit value SOClowR and a lowest threshold value SOClow, and SOCEngStp > SOCEngSt > SOClowR > SOClow; under the control of the hybrid control unit, when a vehicle is in a forward gear, a start/stop management module controls engine start request setting in response to the fact that the battery charge state is smaller than the start threshold value, and controls engine start request resetting in response to the fact that the battery charge state is greater than the stop threshold value; under the control of the hybrid control unit, when the vehicle changes from the reverse gear to a non-reverse gear, the start/stop management module controls the engine start request setting in response to the fact that a forward gear speed is greater than a vehicle speed threshold value or the non-reverse gear time is greater than a time threshold value.

Description

A gear switching method and system based on hybrid power system

This application claims priority to the Chinese patent application with application number 202210783540.6, which was submitted to the China Patent Office on June 27, 2022. The entire content of this application is incorporated into this application by reference.

Technical field

The present application relates to the field of vehicle technology, for example, to a gear switching method and system based on a hybrid power system.

Background technique

At present, hybrid power systems are favored by manufacturers because of their low development difficulty and good power performance. However, they also have characteristics such as difficulty in layout. In order to compress the volume of the entire power system, many hybrid power systems cancel the reverse gear in the transmission and use the power motor to realize the reverse gear function.

However, the switching control between reverse gear and forward gear in the hybrid system becomes more difficult. For example, when starting the engine, and then reverse gear is required, the engine will change to reverse rotation when it is rotating forward. At this time, if the control cannot Otherwise it will cause damage to the system.

Contents of the invention

Embodiments of the present application provide a gear switching method and system based on a hybrid power system to improve the safety and reliability of gear shifting in the hybrid power system.

In a first aspect, embodiments of the present application provide a gear switching method based on a hybrid power system, including:

The vehicle hybrid control unit sets the threshold parameters of the battery charge status of the battery charge status module; the threshold parameters at least include the starting threshold value SOCEngSt, the shutdown threshold value SOCEngStp, the reverse gear lower limit value SOClowR and the minimum Threshold value SOClow; among them, SOCEngStp>SOCEngSt>SOClowR>SOClow;

Under the control of the hybrid control unit, the start-stop management module controls the engine start request to be set in response to the battery charge state being less than the start threshold value when the vehicle is in forward gear; in response to the The battery charge state is greater than the shutdown threshold, and the engine is controlled to start and request reset;

Under the control of the hybrid control unit, when the vehicle changes from reverse gear to non-reverse gear, the start-stop management module controls the engine start request setting in response to the forward gear speed being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold. Bit.

In a second aspect, embodiments of the present application provide a hybrid power system configured to perform the gear switching method described in any one of the first aspects. The hybrid power system includes: a vehicle hybrid control unit, an engine and an integrated type transmission;

The vehicle hybrid control unit includes a battery charge status module and a start-stop management module;

The battery charge status module is set to adjust the threshold parameters of the battery charge status; the threshold parameters include at least a starting threshold value SOCEngSt, a shutdown threshold value SOCEngStp, a reverse gear lower limit value SOClowR and a minimum threshold value. SOClow; among them, SOCEngStp>SOCEngSt>SOClowR>SOClow;

The start-stop management module is configured to control the engine start request to be set in response to the battery charge state being less than the start threshold value when the vehicle is in forward gear; in response to the battery charge state being greater than the stop threshold value; Threshold value, controls the engine start request to reset;

The start-stop management module is also configured to control the engine start request to be set in response to the vehicle speed in forward gear being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear;

The integrated transmission includes a first clutch, a motor and a transmission connected in sequence, and the integrated transmission is configured to realize switching of multiple gears.

Description of drawings

Figure 1 is a flow chart of a gear switching method based on a hybrid power system provided in Embodiment 1 of the present application;

Figure 2 is a flow chart of a gear switching method based on a hybrid power system provided in Embodiment 2 of the present application. process map;

Figure 3 is a flow chart of a gear switching method based on a hybrid power system provided in Embodiment 3 of the present application;

Figure 4 is a schematic diagram of a crawling speed and a crawling vehicle speed provided in Embodiment 3 of the present application;

Figure 5 is a flow chart of a gear switching method based on a hybrid power system provided in Embodiment 4 of the present application;

Figure 6 is a schematic structural diagram of a hybrid power system provided in Embodiment 5 of the present application;

Figure 7 is a schematic structural diagram of an integrated transmission provided by an embodiment of the present application;

Figure 8 is a schematic diagram of a hybrid power system network provided by an embodiment of the present application.

Detailed ways

Embodiment 1

Figure 1 is a flow chart of a gear switching method based on a hybrid power system provided in Embodiment 1 of the present application. Referring to Figure 1, this embodiment can be applied to the situation of adjusting the gear of the hybrid power system. This method It can be executed by the hybrid power system in the embodiment of the present application, wherein the system can be implemented by at least one of software and hardware, and the system can be integrated on the vehicle. The method includes the following steps:

S110. The vehicle hybrid control unit sets the threshold parameters of the battery charge status of the battery charge status module; the threshold parameters include at least the starting threshold SOCEngSt, the stopping threshold SOCEngStp, the reverse gear lower limit SOClowR and the minimum Threshold value SOClow.

Among them, the vehicle hybrid control unit (VCU), as the central control unit of the hybrid vehicle, is the core of the entire control system. The VCU collects motor and battery status, accelerator pedal signals, brake pedal signals, actuator and sensor signals. After comprehensive analysis and making corresponding judgments based on the driver's intentions, it monitors the actions of the lower component controller, which is responsible for the car. Normal driving, braking energy feedback, energy management of the vehicle engine and power battery, network management, fault diagnosis and processing, vehicle status monitoring, etc., thereby ensuring that the vehicle has better power, higher economy and reliability Normal and stable work under normal conditions.

Exemplarily, the vehicle hybrid control unit includes a battery charge state module. The battery charge state module is configured to obtain the battery's state of charge (State of Charge, SOC) under different states. The battery's state of charge is the energy stored in the battery. A relative measure of, defined as the ratio of the amount of charge that can be extracted from the cell at a specific point in time to the total capacity. Accurately estimating the state of charge is important because the battery management system (Battery Management System, BMS) uses the estimated state of charge to prompt the user about the expected available power before recharging, ensuring that the battery is within a safe operating range and implementing control strategies. And ultimately improve battery life.

For example, the threshold parameters of the battery charge state include the starting threshold value SOCEngSt, the stopping threshold value SOCEngStp, the reverse gear lower limit value SOClowR and the lowest threshold value SOClow, and SOCEngStp>SOCEngSt>SOClowR>SOClow. Among them, the starting threshold value SOCEngSt refers to the threshold value for engine starting. In other words, when the battery charge state is less than the starting threshold value SOCEngSt, it is not enough to provide energy to the motor through the battery, and the engine needs to be started to provide energy to the motor. . The shutdown threshold value SOCEngStp refers to the threshold value for engine shutdown. In other words, when the battery charge state is greater than the shutdown threshold value SOCEngStp, the battery has a larger charge and can provide sufficient energy for the motor, that is, the engine can be shut down. Carry out shutdown processing. Moreover, the shutdown threshold value SOCEngStp is greater than the startup threshold value SOCEngSt. The reverse gear lower limit value SOClowR refers to the minimum value of the battery charge when the vehicle is in reverse gear. The lowest threshold value SOClow refers to the minimum charge amount of the battery when the vehicle can operate. In other words, if the battery charge amount is lower than the lowest threshold value SOClow, the vehicle battery is in the feed state. In order to protect the service life of the battery, Then control the vehicle to stop working.

For example, the simple design principle is that SOClowR is greater than SOWlow, the SOC charge difference between SOClowR and SOWlow should be able to ensure a certain number of engine starting capabilities, and the SOC charge difference between SOCEngSt and SOClowR should be able to ensure a certain degree of purity. The electric mileage is ensured to ensure the energy consumption of the vehicle during the normal reversing process. When the charge of the power battery is lower than SOClow, the battery charge status module will limit the discharge capacity of the power battery to 0, that is, to protect the service life of the battery, the vehicle will be controlled to stop working.

S120, the start-stop management module, under the control of the hybrid control unit, sounds when the vehicle is in forward gear. In response to the battery charge state being less than the start threshold, the engine start request is controlled to be set; in response to the battery charge state being greater than the shutdown threshold, the engine start request is controlled to be reset.

Among them, the start-stop management module is set to control the engine to start or stop, that is, the battery charge status module controls the engine to start or stop based on different battery charge status thresholds to achieve hybrid control or pure electric control of the vehicle.

For example, when the hybrid control unit controls the vehicle to be in forward gear, in response to the battery charge state being less than the starting threshold value SOCEngSt, that is, the current charge of the battery is insufficient to provide energy to the motor through the battery, and the engine needs to be started to provide energy to the motor. energy, and then controls the engine start request setting to realize the engine starting to provide energy to the motor. For example, when the engine start request is set, EngStReq=1, that is, 1 is output based on the logical judgment relationship to realize the start of the engine.

At the same time, when the hybrid control unit controls the vehicle to be in forward gear, in response to the battery charge state being greater than the shutdown threshold SOCEngStp, that is, the battery charge is large and can provide sufficient energy to the motor, it then controls the engine start request to reset. , to achieve engine shutdown and suspend the supply of energy to the motor. For example, when the engine starts to request reset, EngStReq=0, that is, 0 is output based on the logical judgment relationship to realize the engine shutdown recovery state.

S130. Under the control of the hybrid control unit, the start-stop management module controls the engine start request setting in response to the forward gear speed being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear. Bit.

For example, when the hybrid control unit controls the vehicle to change from reverse gear to non-reverse gear, that is, from reverse gear to forward gear or neutral, etc., the embodiment of the present application does not limit the gear position of the non-reverse gear. For example, the vehicle speed threshold in the forward gear is the standard speed value at which the vehicle is in the forward gear and the battery provides energy to the motor to realize the forward movement of the vehicle. That is, when the vehicle is in forward gear, if the current forward gear speed is greater than the vehicle speed threshold, the engine needs to be started and energy is also provided for the motor. For example, when the engine start request is set, EngStReq=1, that is, based on logic The judgment relationship outputs 1 to start the engine.

At the same time, the time threshold in forward gear is the standard time value for the vehicle to move forward using the battery to provide energy to the motor. That is, when the vehicle is in forward gear, the current forward gear travel time is greater than At the time threshold, it is currently required to start the engine and provide energy to the motor. For example, when the engine start request is set, EngStReq=1, that is, 1 is output based on the logical judgment relationship to realize the start of the engine. For example, when the engine start request is made, the engine start request is set to EngStReq=1, and when the hybrid control unit controls the vehicle to be in reverse gear, or when the engine start request is invalid, the engine start request is reset to EngStReq=0.

An embodiment of the present application provides a gear switching method based on a hybrid system. The vehicle hybrid control unit sets the threshold parameters of the battery charge state of the battery charge state module; the threshold parameters at least include a starting threshold value. SOCEngSt, shutdown threshold value SOCEngStp, reverse gear lower limit value SOClowR and minimum threshold value SOClow; among them, SOCEngStp>SOCEngSt>SOClowR>SOClow; the start-stop management module is under the control of the hybrid control unit, when the vehicle is in forward gear , in response to the battery charge state being less than the starting threshold, the engine start request is controlled to be set; and in response to the battery charge state being greater than the shutdown threshold, the engine start request is controlled to be reset; the start-stop management module is in the hybrid control unit Under control, when the vehicle changes from reverse gear to non-reverse gear, in response to the forward gear speed being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold, the engine start request is controlled to be set. Based on the gear switching method based on the hybrid power system provided by this application, the safety and reliability of the gear shifting of the hybrid power system can be improved.

Embodiment 2

Figure 2 is a flow chart of a gear switching method based on a hybrid power system provided in Embodiment 2 of the present application. Referring to Figure 2, Embodiment 2 refines the method based on the vehicle based on the above embodiment. The gear position is used to set and reset the engine starting request. In this embodiment, the method includes the following steps:

S210. The vehicle hybrid control unit sets the threshold parameters of the battery charge status of the battery charge status module; the threshold parameters include at least the starting threshold value SOCEngSt, the shutdown threshold value SOCEngStp, the reverse gear lower limit value SOClowR and the minimum Threshold value SOClow.

S220. Under the control of the hybrid control unit, the start-stop management module controls the engine start request to be set in response to the battery charge state being less than the start threshold when the vehicle is in forward gear; in response to the battery charge state If the load state is greater than the shutdown threshold, the engine is controlled to start and request reset.

S230. Under the control of the hybrid control unit, the start-stop management module controls the engine start request setting in response to the forward gear speed being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear. Bit.

S240, the start-stop control module, under the control of the hybrid control unit, controls the engine start when the engine start request is set.

Among them, the start-stop control module is set to control the engine to start or stop, that is, to realize hybrid control or pure electric control of the vehicle. Among them, hybrid control means that both the battery and the engine provide energy to the motor, and pure electric control means that the battery provides energy to the motor.

For example, when the engine start request is set, that is, EngStReq = 1, that is, 1 is output based on the logical judgment relationship to implement engine starting. The hybrid control unit controls the engine to start, and the engine begins to provide energy to the motor.

S250, controls the first clutch to be combined with the engine; drives the engine to a certain speed through the motor, and controls the ignition of the engine's fuel injection point to make the engine run.

When the first clutch is combined with the engine, the energy provided by the engine can be transmitted to the motor through the first clutch, ensuring that the hybrid control unit controls the vehicle to operate in the hybrid mode. For example, the engine fuel injection point is controlled to ignite to run the engine, and the engine responds to requests such as torque and gear speed from the hybrid control unit. That is, based on the vehicle's demand for engine starting, the first clutch, the vehicle's dual clutch and transmission, etc., perform fuel injection and oil filling to ensure that the engine rotation drives the gears in the transmission to rotate, thereby enabling the engine to provide energy.

S260, the start-stop control module, under the control of the hybrid control unit, controls the engine to stop when the engine start request is reset.

For example, when the engine starts to request a reset, that is, EngStReq=0, that is, based on logical judgment, the The system outputs 0 to stop the engine. The hybrid control unit controls the engine to stop, and the engine pauses to provide energy to the electric motor.

S270: Control the engine torque to drop to zero, and control the first clutch to separate from the engine; and control the engine injection point to stop fuel injection to slow the engine down to zero.

Among them, the engine torque is controlled to drop to zero, that is, the engine does not transmit power to the motor. For example, by separating the first clutch from the engine, that is, the energy provided by the engine can be transmitted to the motor through the disconnection of the first clutch, ensuring that the hybrid control unit controls the vehicle to operate in a pure electric mode. For example, the engine injection point is controlled to stop fuel injection to slow down the engine to zero, that is, based on the vehicle's demand for engine shutdown, the first clutch and the vehicle's dual clutch and transmission, etc., stop fuel injection and refueling, etc. to ensure that the engine Disconnected from the transmission, suspends the engine to provide energy to the motor, which in turn keeps the battery providing energy to the motor.

In summary, the gear switching method based on the hybrid power system provided by the embodiment of the present application sets and resets the engine start request based on the vehicle gear requirements, and realizes the battery in the vehicle to provide energy for the motor, that is, pure electric control, or realizes Both the battery and the engine in the vehicle provide energy to the motor, that is, hybrid power control, ensuring the safety and reliability of the hybrid system's shifting.

Embodiment 3

Figure 3 is a flow chart of a gear switching method based on a hybrid power system provided in the third embodiment of the application. Figure 4 is a schematic diagram of a crawling speed and crawling vehicle speed provided in the third embodiment of the application. Refer to Figure 3 and Figure As shown in 4, this third embodiment is refined based on the above embodiment, and details how the hybrid control unit regulates the crawling control module based on vehicle gear adjustment. In this embodiment, the method includes the following steps:

S310. The vehicle hybrid control unit sets the threshold parameters of the battery charge status of the battery charge status module; the threshold parameters include at least the starting threshold SOCEngSt, the stopping threshold SOCEngStp, the reverse gear lower limit SOClowR and the minimum Threshold value SOClow.

S320. Under the control of the hybrid control unit, the start-stop management module controls the engine start request to be set in response to the battery charge state being less than the start threshold when the vehicle is in forward gear; in response to the battery charge state If the load state is greater than the shutdown threshold, the engine is controlled to start and request reset.

S330. Under the control of the hybrid control unit, the start-stop management module controls the engine start request setting in response to the forward speed being greater than the vehicle speed threshold or the non-reverse time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear. Bit.

S340, the crawl control module is under the control of the hybrid control unit, when the vehicle is in the crawl mode, in response to the gear being in the forward gear, and in the state of not receiving the engine start request, the motor speed is controlled to the crawl speed.

Among them, the crawl control module is when the driver engages forward gear or reverse gear, and if the pressure of the brake master cylinder is less than the standard pressure value of the master cylinder, the throttle is less than the standard throttle value, and the vehicle speed is less than the standard vehicle speed value, the vehicle will enter the crawl mode. . Among them, the master cylinder included in the engine is used to realize the engine rotation process. The standard pressure value of the master cylinder, the standard throttle value and the standard vehicle speed value are the standard thresholds of the vehicle in the current gear. When the above standard thresholds are not met, the hybrid control The unit controls the crawl control module to place the vehicle in crawl mode.

For example, the crawl control module is under the control of the hybrid control unit, when the vehicle is in crawl mode, when the current gear of the vehicle is forward gear and the engine start request is not set, that is, the engine start request is not received. , when the engine is not required to provide energy to the motor, the motor speed is controlled to be the crawl speed to ensure that the hybrid control unit controls the crawl control module to keep the vehicle in crawl mode.

S350, the crawling control module, under the control of the hybrid control unit, when the vehicle is in crawling mode, responds to the gear position being in forward gear, and upon receiving the engine start request, controls the motor speed to the crawling speed and controls the engine to start. machine.

Among them, the crawl control module is under the control of the hybrid control unit, when the vehicle is in the crawl mode, responds to the vehicle's current gear being still forward gear, and the engine start request is set, that is, it receives the engine start request, and needs When the engine provides energy to the motor, it continues to control the motor speed to crawl speed. At the same time, the hybrid control unit controls the first clutch to increase the engine starting torque. After the engine speed rises to the injection ignition speed, the hybrid control unit controls the engine injection speed. After the oil is ignited and the engine is started, the hybrid control unit controls the engine to work in torque mode and controls the combination of the engine and the motor through the first clutch. Ensure that the engine provides energy to the motor.

S360, the crawl control module, under the control of the hybrid control unit, when the vehicle is in crawl mode, responds to the gear shift from forward gear to reverse gear, controls the engine torque to zero, and controls the motor speed to crawl speed; in response to the engine The torque is zero, and the motor speed is controlled to be a negative crawling speed.

Among them, the crawl control module is under the control of the hybrid control unit. When the vehicle is in crawl mode and the current gear of the vehicle is forward gear and switched to other gears, the torque of the engine is controlled to zero, and the hybrid control unit controls the first clutch. Separate, and at the same time send a fuel cut command to control the transition of the motor from positive crawling speed to negative crawling speed, thereby realizing the vehicle to execute the switched gear.

Optionally, the motor speed is controlled to transition from crawling speed to negative crawling speed according to a preset slope.

For example, as shown in FIG. 4 , the motor is controlled to switch according to the slope of the curve between the positive crawling speed and the negative crawling speed in FIG. 4 .

S370, the crawling control module, under the control of the hybrid control unit, when the vehicle is in crawling mode, responds to the gear being reverse gear and controls the motor speed to be a negative crawling speed.

Among them, the crawling control module is under the control of the hybrid control unit. When the vehicle is in crawling mode and the current gear of the vehicle is reverse gear, the motor speed is controlled to be a negative crawling speed. That is, the vehicle realizes reverse movement, and the hybrid control unit controls the vehicle to execute reverse gear. The hybrid control unit realizes the adjustment and conversion of different gears of the vehicle to improve the safety and reliability of the hybrid system's gear shifting.

In summary, the embodiments of the present application use the hybrid control unit to regulate the crawl control module based on the vehicle gear adjustment, control the motor speed to execute different crawl speeds, and realize the adjustment and conversion of different vehicle gears, so as to improve the performance of the hybrid system. Safe and reliable shifting.

Embodiment 4

Figure 5 is a flow chart of a gear switching method based on a hybrid system provided in Embodiment 4 of the present application. Referring to Figure 5 , Embodiment 4 refines the hybrid control based on the above embodiment. How the unit adjusts the gear position based on the vehicle battery charge state. In this embodiment, the method includes the following steps:

S410. The vehicle hybrid control unit sets the threshold value of the battery charge state of the battery charge state module. Parameters; the threshold parameters include at least the starting threshold value SOCEngSt, the stopping threshold value SOCEngStp, the reverse gear lower limit value SOClowR and the lowest threshold value SOClow.

S420. Under the control of the hybrid control unit, the start-stop management module controls the engine start request to be set in response to the battery charge state being less than the start threshold when the vehicle is in forward gear; in response to the battery charge state being greater than the shutdown threshold limit, control the engine start request to reset.

S430. Under the control of the hybrid control unit, the start-stop management module controls the engine start request setting in response to the forward speed being greater than the vehicle speed threshold or the non-reverse time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear. Bit.

S440. In response to the battery charge state SOC<SOClowR, the hybrid control unit sends a reverse gear prohibition instruction to the transmission control unit; and sends at least one of a text and image prompt of the reverse gear prohibition instruction to the instrument display module.

For example, when the hybrid control unit controls the vehicle to be in reverse gear, if the battery charge state SOC is less than the reverse gear lower limit value SOClowR, that is, the current state of the vehicle does not meet the conditions for executing reverse gear, the hybrid control unit will send the signal to the transmission. The control unit sends a reverse gear prohibition command. For example, when generating a reverse gear prohibition instruction, text prompts or image prompts can be sent to the instrument display module to facilitate the driver to understand the current vehicle situation and ensure the stability and reliability of the gear adjustment.

S450. In response to the battery charge state SOC>SOClowR+deltaSOC, the hybrid control unit sends a reverse gear permission instruction to the transmission control unit; and sends at least one of a reverse gear permission instruction text and an image prompt to the instrument display module.

For example, when the battery state of charge SOC is slightly greater than the reverse gear lower limit value SOClowR and the vehicle's current state cannot immediately execute reverse gear, the hybrid control unit does not send a reverse gear permission instruction to the transmission control unit. When the battery state of charge SOC is greater than the reverse gear lower limit value SOClowR, and the battery charge state SOC > the reverse gear lower limit value SOClowR + deltaSOC, where deltaSOC is the transition value of the charge, the current state of the vehicle can perform reverse gear, then hybrid The control unit sends a reverse gear enable command to the transmission control unit. For example, when generating a reverse gear permission instruction, text prompts or image prompts can be sent to the instrument display module to facilitate the driver to understand the current vehicle situation and ensure the stability and stability of the gear adjustment. reliable.

S460, the hybrid control unit obtains the gear information sent by the transmission control unit in real time; and in response to the vehicle being in forward gear, controls the battery charge state to be lower than the shutdown threshold.

Among them, in order to ensure that the hybrid control unit can accurately adjust the gear position, the hybrid control unit can obtain the gear information sent by the transmission control unit in real time, and determine the gear adjustment situation based on the gear information and the corresponding battery charge state. To improve the safety and reliability of the hybrid system's gear shifting.

For example, when the vehicle is in the forward gear, the hybrid control unit controls the battery state of charge SOC to be lower than the shutdown threshold SOCEngStp, that is, the engine does not request a reset, and the engine provides energy to the motor to ensure that the vehicle smoothly executes the forward gear. That is, the real-time gear position is sent to the hybrid control unit, and the hybrid control unit performs related operations. The hybrid control unit strictly controls the vehicle battery charge state SOC to be lower than the shutdown threshold value SOCEngStp during the forward gear vehicle control process to ensure that there is Enough power.

In summary, the embodiment of the present application provides a gear switching method based on a hybrid power system, which exemplarily details how the hybrid control unit realizes gear adjustment based on the vehicle battery charge state, and realizes the adjustment and control of different gears of the vehicle. conversion to improve the safety and reliability of the hybrid system's shifting.

Embodiment 5

Figure 6 is a schematic structural diagram of a hybrid power system provided in Embodiment 5 of the present application. Figure 7 is a schematic structural diagram of an integrated transmission provided in an embodiment of the present application. Figure 8 is a schematic structural diagram of a hybrid power system provided in an embodiment of the present application. A schematic diagram of a system network. The system can be applied to vehicles with gear adjustment, where the system can be implemented by at least one of software and hardware.

As shown in FIG. 6 , the hybrid system 10 includes: a vehicle hybrid control unit 100 , an engine 200 and an integrated transmission 300 ; the vehicle hybrid control unit 100 includes a battery charge status module 110 and a start-stop management module 120 .

Among them, the battery charge state module 110 is set to adjust the threshold value parameters of the battery charge state; the threshold value parameters at least include the starting threshold value SOCEngSt, the stop threshold value SOCEngStp, the reverse gear lower limit value SOClowR and the lowest threshold value SOClow ;Among them, SOCEngStp>SOCEngSt> SOClowR>SOClow.

The start-stop management module 120 is configured to, when the vehicle is in forward gear, control the engine start request setting in response to the battery charge state being less than the start threshold; and control the engine start request in response to the battery charge state being greater than the stop threshold. reset.

The start-stop management module 120 is also configured to control the engine start request to be set in response to the forward speed being greater than the vehicle speed threshold or the non-reverse time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear.

Referring to FIG. 7 , the integrated transmission 300 includes a first clutch 310 , a motor 320 and a transmission 330 that are connected in sequence. The integrated transmission 300 is configured to realize switching of multiple gears. By using the integrated transmission 300, the size of the hybrid system 10 can be better reduced.

Optionally, as shown in FIG. 8 , the hybrid system 10 also includes: a power motor controller 400 configured to report the rotation speed and torque to the hybrid control unit and accept the rotation speed instructions and torque instructions from the hybrid control unit. The battery management system 500 is configured to report battery charging and discharging power and battery charge status to the hybrid control unit. The transmission control unit 600 is configured to control the crawling speed of the vehicle and report gear information and crawling torque to the hybrid control unit. The electronic stability control system 700 is configured to upload the brake master cylinder pressure signal and pedal signal to the hybrid control unit, and perform anti-lock braking operation when the vehicle is running. The engine management unit 800 is configured to receive the starting command and the fuel injection ignition command from the hybrid control unit to perform the starting operation, and respond to the driver's torque or speed command after the starting is completed. The DC conversion unit 900 is configured to convert the high level to the low level after the hybrid system is powered on. The power motor controller 400, the battery management system 500, the transmission control unit 600, the electronic stability control system 700, the engine management unit 800 and the DC conversion unit 900 are communicatively connected through the gateway 1, which is not limited in the embodiment of the present application.

In summary, the hybrid power system provided by the embodiment of the present application adjusts the threshold parameters of the battery charge state through the battery charge state module; the threshold parameters at least include the starting threshold SOCEngSt, the stopping threshold SOCEngStp, the reverse gear The limit value SOClowR and the lowest threshold value SOClow. Then, through the start-stop management module, when the vehicle is in forward gear, in response to the battery charge state being less than the start threshold, the engine start request is controlled to be set; in response to the battery charge state being greater than the stop threshold, the engine start request is controlled reset. For example, when the vehicle changes from reverse gear to non-reverse gear, the start-stop management module controls the engine start request to be set in response to the forward gear speed being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold. And the integrated transmission includes a first clutch, a motor and a transmission connected in sequence, and the integrated transmission is configured to realize switching of multiple gears. Based on the hybrid power system provided by this application, the safety and reliability of gear shifting of the hybrid power system can be improved.

Claims

A gear switching method based on a hybrid power system, including:

The vehicle hybrid control unit sets the threshold parameters of the battery charge status of the battery charge status module; the threshold parameters at least include the starting threshold value SOCEngSt, the shutdown threshold value SOCEngStp, the reverse gear lower limit value SOClowR and the minimum Threshold value SOClow; among them, SOCEngStp>SOCEngSt>SOClowR>SOClow;

Under the control of the hybrid control unit, the start-stop management module controls the engine start request to be set in response to the battery charge state being less than the start threshold value when the vehicle is in forward gear; in response to the The battery charge state is greater than the shutdown threshold, and the engine is controlled to start and request reset;

Under the control of the hybrid control unit, when the vehicle changes from reverse gear to non-reverse gear, the start-stop management module controls the engine start request setting in response to the forward gear speed being greater than the vehicle speed threshold or the non-reverse gear time being greater than the time threshold. Bit.
The gear switching method based on the hybrid power system according to claim 1, further comprising:

The start-stop control module, under the control of the hybrid control unit, controls the engine start when the engine start request is set;

Under the control of the hybrid control unit, the start-stop control module controls the engine to stop when the engine start request is reset.
The gear switching method based on the hybrid power system according to claim 2, wherein:

Control engine starting, including:

Control the first clutch to be combined with the engine; drag the engine to a certain speed through the motor, and control the ignition of the engine fuel injection point to make the engine run;

Control engine shutdown, including:

The engine torque is controlled to drop to zero, and the first clutch is controlled to be separated from the engine; and the engine fuel injection point is controlled to stop fuel injection to decelerate the engine to zero.
The gear switching method based on the hybrid power system according to claim 1, further comprising:

Under the control of the hybrid control unit, when the vehicle is in crawling mode, the crawling control module controls the motor speed to be in response to the gear position being in forward gear and without receiving the engine start request. crawling speed;

Under the control of the hybrid control unit, when the vehicle is in crawling mode, in response to the gear position being in forward gear and receiving an engine start request, the crawling control module controls the motor speed to be the crawling speed and controls engine start;

The crawl control module is controlled under the control of the hybrid control unit, when the vehicle is in the crawl mode, in response to the gear shifting from forward gear to reverse gear, controls the engine torque to zero, and controls the motor speed to the crawl speed; in response to The engine torque is zero, and the motor speed is controlled to be a negative crawling speed.
The gear switching method based on the hybrid power system according to claim 4, wherein controlling the motor speed to a negative crawling speed includes:

Control the motor speed to transition from crawling speed to negative crawling speed according to the preset slope.
The gear switching method based on the hybrid power system according to claim 4, further comprising:

Under the control of the hybrid control unit, when the vehicle is in the crawling mode, the crawling control module controls the motor speed to be a negative crawling speed in response to the gear being reverse gear.
The gear switching method based on the hybrid power system according to claim 1, further comprising:

In response to the battery charge state SOC<SOClowR, the hybrid control unit sends a reverse gear prohibition instruction to the transmission control unit; and sends at least one of the text and image prompts of the reverse gear prohibition instruction to the instrument display module;

In response to the battery charge state SOC>SOClowR+deltaSOC, the hybrid control unit sends a reverse gear permission instruction to the transmission control unit; and sends at least one of the reverse gear permission instruction text and an image prompt to the instrument display module.
The gear switching method based on the hybrid power system according to claim 1, further comprising:

The hybrid control unit obtains the gear information sent by the transmission control unit in real time; and in response to the vehicle being in forward gear, controls the battery charge state to be lower than the shutdown threshold.
A hybrid power system, configured to perform the gear switching method according to any one of claims 1 to 8, the hybrid power system includes: a vehicle hybrid control unit (100), an engine (200) and an integrated transmission(300);

The vehicle hybrid control unit (100) includes a battery charge status module (110) and a start-stop management module (120);

The battery charge status module (110) is set to adjust the threshold parameters of the battery charge status; the threshold parameters at least include starting threshold SOCEngSt, shutdown threshold SOCEngStp, reverse gear lower limit SOClowR and minimum Threshold value SOClow; among them, SOCEngStp>SOCEngSt>SOClowR>SOClow;

The start-stop management module (120) is configured to control the engine (200) start request setting in response to the battery charge state being less than the starting threshold when the vehicle is in forward gear; in response to the battery The charge state is greater than the shutdown threshold, and the engine (200) is controlled to start and request reset;

The start-stop management module (120) is also configured to control the start request setting of the engine (200) in response to the forward speed being greater than the vehicle speed threshold or the non-reverse time being greater than the time threshold when the vehicle changes from reverse gear to non-reverse gear. Bit;

The integrated transmission (300) includes a first clutch (310), a motor (320) and a transmission (330) connected in sequence, and the integrated transmission (140) is configured to realize switching of multiple gears.
The hybrid system of claim 9, further comprising:

A power motor controller (400) configured to report rotational speed and torque to the hybrid control unit (100), and accept rotational speed instructions and torque instructions from the hybrid control unit (100);

A battery management system (500) configured to report battery charging and discharging power and battery charge status to the hybrid control unit (100);

The transmission control unit (600) is configured to control the crawling speed of the vehicle, and report gear information and crawling torque to the hybrid control unit (100);

The electronic stability control system (700) is configured to upload the brake master cylinder pressure signal and pedal signal to the hybrid control unit (100), and perform anti-lock braking operation when the vehicle is driving;

The engine management unit (800) is configured to receive the starting command and the fuel injection ignition command from the hybrid control unit (100) to perform the starting operation, and respond to the driver's torque or speed command after the starting is completed;

DC conversion unit (900), configured to convert the high level to Change to low level.