Shift control method and device for a hybrid vehicle

Abstract

The application discloses a shift control method and device of a hybrid vehicle, and relates to the technical field of vehicle shift control. The shift control method obtains a wheel end demand torque and a driving speed of the hybrid vehicle, and determines whether a target state of switching a direct drive gear is reached according to the wheel end demand torque and the driving speed. Since the direct drive gear is a gear in which a driving motor and an engine of the hybrid vehicle both output a torque to a wheel end, and a generator connected with the engine is locked, the control indexes of basic power and economic fuel consumption can be met, and the hybrid vehicle is directly switched to the direct drive gear when the switching condition of the direct drive gear is met. When the switching condition is not met, the hybrid vehicle is controlled to drive in other driving gears, and is shifted to the direct drive gear in time when the target state is reached. The control method can make the response level of the direct drive gear higher, and thus the power and energy consumption economy of the hybrid vehicle can be considered in the driving process.

Description

Technical Field

[0001] This invention relates to the technical field of gear shift control for hybrid vehicles, and more particularly to a gear shift control method and apparatus for hybrid vehicles. Background Technology

[0002] Power-split ECVT (Electrically Controlled Continuously Variable Transmission) is gradually becoming the mainstream hybrid powertrain, achieving vehicle performance goals while considering operating costs. To further reduce fuel consumption and increase driving range, an EV (Electric Vehicle) mode is added to achieve pure electric and multi-speed driving modes, balancing power and fuel economy. For multi-speed ECVT hybrid transmissions, which integrate multiple operating modes and gears for pure electric and hybrid drive, the challenges arise from the complex and varied driving conditions, differences in optimal gear control for energy management throughout the entire lifecycle under different conditions, and the varying demands for acceleration power and long driving range in different usage scenarios. Therefore, it is necessary to integrate multi-speed drive modes from different driving methods. Currently, there is a lack of intelligent shifting strategies to select modes and gears to adapt to different driving conditions and environments in terms of power and energy economy.

[0003] Therefore, how to make hybrid vehicles balance power and energy economy is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] The present invention provides a shift control method and device for hybrid vehicles, which enables hybrid vehicles to balance power and energy economy.

[0005] The embodiments of the present invention provide the following solutions:

[0006] In a first aspect, embodiments of the present invention provide a shift control method for a hybrid vehicle, the method comprising:

[0007] Obtain the wheel-end torque requirement and driving speed of the hybrid vehicle;

[0008] Based on the required torque at the wheel ends and the vehicle speed, determine whether the target state for switching to direct drive mode has been reached. Direct drive mode is a mode in which both the drive motor and engine of a hybrid vehicle output torque to the wheel ends and lock the generator that is connected to the engine.

[0009] If so, then control the hybrid vehicle to switch to direct drive mode;

[0010] If not, the hybrid vehicle is controlled to drive in other drive gears, and shifted to direct drive gear when the hybrid vehicle reaches the target driving state.

[0011] In one optional embodiment, the direct-drive gears include direct-drive first gear, direct-drive second gear, direct-drive third gear, and direct-drive fourth gear, with the output speed ratios of the direct-drive gears decreasing sequentially from direct-drive first gear to direct-drive fourth gear; controlling the hybrid vehicle to switch to direct-drive gears includes:

[0012] Obtain the current operating mode of the hybrid vehicle;

[0013] When the current operating mode is automatic or fuel-saving mode, determine whether the driving speed is less than the first speed threshold.

[0014] When the vehicle speed is less than the first speed threshold, the hybrid vehicle will switch to direct drive second or third gear according to the wheel end torque demand and the vehicle speed.

[0015] When the vehicle speed is not less than the first speed threshold, switch the hybrid vehicle to direct drive fourth gear;

[0016] When the current operating mode is Sport mode, the hybrid vehicle will switch to direct drive mode 1, direct drive mode 2 or direct drive mode 3 according to the torque required at the wheel ends and the vehicle speed.

[0017] In one alternative embodiment, before controlling the hybrid vehicle to switch to direct drive, the method further includes:

[0018] Based on the wheel-end torque requirement, vehicle speed, and preset shift MAP, determine whether there is a risk of shift failure when switching to direct drive gears;

[0019] If not, control the hybrid vehicle to switch to direct drive mode;

[0020] If so, the hybrid vehicle will be kept in the current drive gear.

[0021] In one optional embodiment, other drive gears include a pure electric gear and an ECVT gear, wherein the ECVT gear is a gear in which both the drive motor and the engine output torque to the wheel ends, and the generator is not locked; controlling the hybrid vehicle to drive in other drive gears includes:

[0022] To obtain the remaining charge of the power battery in a hybrid vehicle;

[0023] Determine whether the remaining battery power is greater than the preset battery power threshold and whether the required torque at the wheel end is less than the preset torque threshold;

[0024] If so, then control the hybrid vehicle to drive in pure electric mode;

[0025] If not, control the hybrid vehicle to drive in ECVT mode.

[0026] In one optional embodiment, the ECVT gears include ECVT first gear and ECVT second gear, wherein the output speed ratio of ECVT first gear is greater than the output speed ratio of ECVT second gear; controlling the hybrid vehicle to operate in ECVT gears includes:

[0027] When the hybrid vehicle is running in Sport mode, the hybrid vehicle is controlled to drive in first gear based on ECVT.

[0028] When the hybrid vehicle is running in automatic mode, the hybrid vehicle is controlled to drive in ECVT first gear, and when the hybrid vehicle accelerates to the second speed threshold, it switches to ECVT second gear.

[0029] When the hybrid vehicle is running in fuel-saving mode, the hybrid vehicle is controlled to drive in second gear based on ECVT.

[0030] In one optional embodiment, after controlling the hybrid vehicle to switch to direct drive mode, the method further includes:

[0031] Obtain traffic congestion information for the roads where hybrid vehicles are to travel;

[0032] Based on congestion information, the remaining charge of the hybrid vehicle's power battery is configured as the target charge, which is the charge level at which the hybrid vehicle can pass through the road to be driven with minimal energy consumption.

[0033] In one optional embodiment, after controlling the hybrid vehicle to switch to direct drive mode, the method further includes:

[0034] Acquire historical energy consumption data and navigation data for the route to be traveled from hybrid vehicles;

[0035] Historical energy consumption data and navigation data are input into a preset calculation model, and the parameter thresholds for hybrid vehicles to perform gear shifting actions are obtained based on the output of the calculation model.

[0036] The corresponding threshold for performing a gear shift action is updated based on the parameter threshold.

[0037] Secondly, embodiments of the present invention also provide a shift control device for a hybrid vehicle, the device comprising:

[0038] The first acquisition module is used to acquire the wheel-end torque requirement and driving speed of the hybrid vehicle;

[0039] The first determining module is used to determine whether the target state of switching to direct drive mode has been reached based on the wheel end torque demand and vehicle speed. The direct drive mode is a mode in which both the drive motor and engine of the hybrid vehicle output torque to the wheel end and lock the generator that is connected to the engine.

[0040] The first control module is used to control the hybrid vehicle to switch to direct drive mode when it is determined that a direct drive mode should be switched.

[0041] The second control module is used to determine whether to switch to direct drive gears, and then control the hybrid vehicle to drive in other drive gears, and to switch to direct drive gears when the hybrid vehicle reaches the target driving state.

[0042] Thirdly, embodiments of the present invention also provide an electronic device, including a processor and a memory, the memory being coupled to the processor, the memory storing instructions that, when executed by the processor, cause the electronic device to perform the steps of any of the methods in the first aspect.

[0043] Fourthly, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the methods in the first aspect.

[0044] The shift control method and apparatus for a hybrid vehicle of the present invention have the following advantages compared with the prior art:

[0045] The shift control method of this invention acquires the wheel-end torque demand and vehicle speed of the hybrid vehicle. Based on these parameters, it determines whether the target state for switching to direct drive has been reached. Since direct drive is the gear where both the drive motor and engine of the hybrid vehicle output torque to the wheels and lock the generator connected to the engine, no power is allocated to the generator for power generation when the hybrid vehicle is driven in direct drive mode. This satisfies the basic control indicators of power and fuel economy. When the hybrid vehicle meets the switching conditions for direct drive, it directly switches to direct drive mode; when the switching conditions are not met, the hybrid vehicle is controlled to drive in other drive gears, and shifts to direct drive mode promptly when the hybrid vehicle's driving state reaches the target state. This control method allows the hybrid vehicle to preferentially use direct drive mode under different driving conditions. Direct drive mode has a higher response level, thus balancing power and fuel economy during the hybrid vehicle's operation. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A flowchart of a gear shift control method for a hybrid vehicle provided in an embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of the structure of a transmission for a hybrid vehicle provided in an embodiment of the present invention;

[0049] Figure 3 The shift MAP for direct drive gears provided in this embodiment of the invention Figure 1 ;

[0050] Figure 4 The shift MAP for direct drive gears provided in this embodiment of the invention Figure 2 ;

[0051] Figure 5 This is a shift map of automatic mode provided in an embodiment of the present invention;

[0052] Figure 6 This is a shift map of the motion modes provided in an embodiment of the present invention;

[0053] Figure 7 A flowchart of adaptive shift control provided in an embodiment of the present invention;

[0054] Figure 8 This is a schematic diagram of the gear shift control device for a hybrid vehicle provided in an embodiment of the present invention. Detailed Implementation

[0055] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the protection scope of the embodiments of the present invention.

[0056] Currently, hybrid vehicles have two hybrid control modes: EV drive mode and ECVT drive mode. EV drive mode enables pure electric drive, while the main function of ECVT drive mode is to achieve power split assist and power generation. The above two control methods result in a tradeoff between the power and energy economy of hybrid vehicles during driving. The following embodiments of the present invention will specifically illustrate how to solve the above technical problems.

[0057] Please see Figure 1 , Figure 1 The flowchart illustrates a shift control method for a hybrid vehicle according to an embodiment of the present invention. This shift control method can be applied to the transmission control unit (TCU) of a hybrid vehicle to implement shift control. The control method includes:

[0058] S11. Obtain the wheel-end torque demand and driving speed of the hybrid vehicle.

[0059] Specifically, the wheel-end torque requirement represents the torque that the power unit of the hybrid vehicle needs to output to the wheels based on driving requirements. It can be obtained by the vehicle controller of the hybrid vehicle after the driver operates the accelerator pedal. The vehicle speed represents the speed of the hybrid vehicle during driving. It can be obtained by collecting data from the vehicle speed sensor installed on the hybrid vehicle. After obtaining the wheel-end torque requirement and the vehicle speed, proceed to step S12.

[0060] S12. Based on the required torque at the wheel ends and the vehicle speed, determine whether the target state for switching to direct drive gear has been reached. Direct drive gear is a gear in which both the drive motor and engine of a hybrid vehicle output torque to the wheel ends and lock the generator connected to the engine.

[0061] Specifically, gear shifting in hybrid vehicles is implemented based on an overall demand for both power and fuel economy. Please refer to [link / reference]. Figure 2 , Figure 2 This is a schematic diagram of the transmission structure. In a hybrid vehicle, the power source includes a generator and a drive motor. The engine is connected to a planetary carrier via a reduction gear, and the generator is connected to a sun gear. Synchronizers S1 and S2 are installed between the engine and generator. Synchronizer S1 controls the gear ratio from the ring gear to the wheel end, and synchronizer S2 controls the gear ratio of the planetary carrier. In ECVT mode, when synchronizer S2 is in the intermediate position, the engine and generator are not locked. Synchronizer S1 adjusts the gear ratio from the ring gear to the wheel end, thus switching the final drive ratio to achieve power distribution at different speeds. In direct drive mode, synchronizer S2 locks the engine and generator, and then synchronizer S1 switches gears, allowing the engine to output power through the ring gear for direct drive. Determining whether the target state for switching to direct drive gear has been reached can be based on the shift MAP. The shift MAP contains the corresponding target vehicle speed and target torque for switching to direct drive gear. If the wheel-end torque and driving speed correspond to the target vehicle speed and target torque in the shift MAP, it means that the hybrid vehicle meets the conditions for switching to direct drive gear. After determining whether the target state for switching to direct drive gear has been reached, proceed to step S13 or S14.

[0062] S13. If so, control the hybrid vehicle to switch to direct drive mode.

[0063] Specifically, when a hybrid vehicle reaches the target state of switching to direct drive mode, in order to achieve more ideal power and fuel economy, it can switch to direct drive mode in a timely manner. The corresponding command for direct drive mode can be output to the shift hub, and the shift hub will perform the switching action of direct drive mode.

[0064] For example, the direct drive gears include direct drive first gear, direct drive second gear, direct drive third gear, and direct drive fourth gear. The output speed ratio of the direct drive gears decreases sequentially from direct drive first gear to direct drive fourth gear. Please continue reading. Figure 2 and Table 1 below.

[0065] Table 1

[0066]

[0067] The output speed ratio is the ratio between the first engine speed input to the transmission and the second engine speed output to the differential as a power source. Different output speed ratios are implemented by controlling the transmission. When the direct drive gearbox includes four gears, it can better cover the direct drive control under different driving conditions. Controlling the hybrid vehicle to switch to direct drive gears includes:

[0068] The current operating mode of a hybrid vehicle can be determined based on the vehicle's mode setting. The vehicle operating modes include automatic mode (or NORMAL mode), fuel-saving mode (or ECO mode), and sport mode (or SPORT mode). In automatic mode, the vehicle automatically balances power output and driving energy consumption. In fuel-saving mode, vehicle control focuses more on energy saving, with power performance being secondary. In sport mode, power output is prioritized, with energy saving being secondary.

[0069] When the current operating mode is automatic or fuel-saving mode, determine if the vehicle speed is lower than a first speed threshold. If the vehicle speed is lower than the first speed threshold, based on the wheel-end torque demand and the vehicle speed, switch the hybrid vehicle to direct drive second or third gear. If the vehicle speed is not lower than the first speed threshold, switch the hybrid vehicle to direct drive fourth gear. Please refer to [link / reference]. Figure 3 , Figure 3 This is a shift map in automatic mode. Solid lines represent upshifts, and dashed lines represent downshifts. Once the wheel-end torque demand and vehicle speed match the values ​​in the map, a direct-drive gear shift is initiated. This allows the vehicle to utilize the lower output speed of direct-drive fourth gear at high speeds for fuel economy. In automatic and fuel-saving modes, shift control prioritizes fuel economy while also considering power, selecting direct-drive second, third, and fourth gears. When low speed and high power demand are needed, the vehicle downshifts from the initial gear to direct-drive second gear, gradually shifting up to direct-drive third and fourth gears as vehicle speed increases.

[0070] When the current operating mode is Sport mode, it indicates that the hybrid vehicle's control prioritizes power performance. Based on wheel torque requirements and vehicle speed, the hybrid vehicle will switch to direct drive mode 1, 2, or 3. Please refer to [link / reference]. Figure 4 , Figure 4 This is a shift map for Sport mode. The map shows that in Sport mode, at low speeds, the higher output ratio of direct drive first gear can be used. During low-speed, high-throttle acceleration, shifting to the more powerful, higher-ratio direct drive first and second gears provides better power. At medium to high speeds, switching to the more fuel-efficient, lower-ratio direct drive third gear is used. When low speed and high power demand are present, downshifting from the initial gear to direct drive first gear, upshifting as vehicle speed increases, and deciding whether to use direct drive fourth gear based on high-speed direct drive fuel economy requirements. Switching between direct drive gears is achieved through two synchronizers. For example, when switching to direct drive first gear, synchronizer S2 is moved to the left (S2L state), locking the engine and alternator, while synchronizer S1 is moved to the right (S1R state) to achieve a higher gear ratio. The difference between direct drive second gear and direct drive first gear is that synchronizer S2 switches from the left to the right, while synchronizer S1 remains in its initial position.

[0071] It should be noted that when switching between two adjacent direct drive gears, the decision to shift gears can be made based on the remaining charge (SOC, State of Charge) of the power battery. If the remaining charge is low or the drive motor capacity is limited, the ECVT gear will be used first for charging when accelerating at low speeds and with high throttle, and downshifting will not be performed. After the vehicle accelerates, it will gradually transition to direct drive third gear and direct drive fourth gear. In other words, the transition between adjacent direct drive gears can be made through the ECVT gear.

[0072] In practical applications, performing a gear shift requires comprehensive consideration of vehicle speed and wheel-side power demand. If the engine cannot smoothly transition during gear shifting, it may cause shift jerking or engine stalling. Therefore, in one specific implementation, before controlling the hybrid vehicle to switch to direct drive, the method further includes:

[0073] Based on the wheel-end torque demand, vehicle speed, and the preset shift MAP, it is determined whether there is a risk of shift failure when switching to direct drive. The shift MAP determines the target torque and target speed for switching to direct drive. If the vehicle speed and wheel-end torque are both at the target values, there is no risk of shift failure. To balance power and fuel economy, the hybrid vehicle should be actively switched to direct drive. Conversely, if neither the wheel-end torque demand nor the vehicle speed reaches the corresponding values ​​in the shift MAP, there is a risk of shift failure, and the hybrid vehicle should be kept in the current drive gear. The current drive gear can be either pure electric or ECVT. To avoid the energy consumption of pure electric mode, stalling due to excessively low RPM in direct drive, or noise issues due to excessively high RPM, a fail-shift mode can be configured. In fail-shift mode, when shifting is difficult or impossible, ECVT is prioritized as the sole drive mode.

[0074] Under normal conditions, the direct-drive gear in the shift MAP is used as the target gear. The vehicle gradually transitions from the current optimal operating mode to the target direct-drive gear as the vehicle speed and wheel-end power demand change. During gear shifting, the decision is made based on the generator's shifting speed regulation and the actual position of the shift hub. The final decision is whether to maintain the current gear or perform a shift, and the decision is sent to the transmission controller for execution. This ensures that the hybrid electric vehicle prioritizes direct-drive gears. If the shifting conditions for direct-drive gears are not met, step S14 is executed.

[0075] S14. If not, control the hybrid vehicle to drive in other drive gears, and shift to direct drive gear when the hybrid vehicle reaches the target driving state.

[0076] Specifically, other drive modes can be pure electric mode, which provides torque to the wheels via the drive motor; or ECVT mode, which provides torque to the wheels through both the engine and the drive motor. ECVT mode can achieve power-split assist and power generation. When the hybrid vehicle reaches the target state for switching to direct drive mode, the transmission is promptly controlled to switch to direct drive mode.

[0077] For example, other drive gears include pure electric gear and ECVT gear, where the ECVT gear is a gear in which both the drive motor and the engine output torque to the wheels, and the generator is not locked; controlling the hybrid vehicle to drive in other drive gears includes:

[0078] The first step is to obtain the remaining power of the hybrid vehicle's battery. This can be determined by the current output voltage of the battery and the preset voltage-to-power correspondence.

[0079] The second step is to determine whether the remaining battery power is greater than a preset battery power threshold and whether the wheel-end torque requirement is less than a preset torque threshold. Since hybrid vehicles consume more energy when operating in pure electric mode, determining whether the remaining battery power exceeds the battery power threshold helps determine if the conditions for pure electric drive are met. Under low torque conditions, the power demand is lower, so pure electric mode is prioritized.

[0080] The third step is to control the hybrid vehicle to drive in pure electric mode if the remaining battery power is greater than the battery power threshold and the required torque at the wheel end is less than the torque threshold. If the conditions for pure electric mode are met, the hybrid vehicle will be controlled to drive in pure electric mode. If not, it means that the required driving torque is too large or that the power battery needs to be recharged. In this case, the hybrid vehicle will be controlled to drive in ECVT mode. Please refer to Table 2 below.

[0081] Table 2

[0082] driving speed Low SOC, high or low power High SOC, low power requirements High SOC, high power requirements low speed ECVT or series pure electric gear ECVT gear medium speed ECVT gear pure electric gear ECVT gear high speed direct drive gear pure electric gear direct drive gear

[0083] Table 2 shows the gear selection table for hybrid electric vehicles based on power demand and vehicle speed. There is a corresponding relationship between power demand and wheel-side torque demand, with power demand representing wheel-side torque demand in the table. Specifically, the series gear selection achieves speed synchronization by locking the engine and generator using synchronizer S2, and controls synchronizer S1 to the intermediate state, cutting off the external power output of the ECVT system's ring gear, thus realizing the series power generation function.

[0084] When the direct drive gear includes four gears, the gear selection table is shown in Table 3, based on the remaining battery power, required power, and driving speed.

[0085] Table 3

[0086] driving speed Low SOC, high or low power High SOC, low power requirements High SOC, high power requirements low speed ECVT gear pure electric gear ECVT or direct drive, first or second gear medium speed ECVT gear pure electric gear ECVT or direct drive in second or third gear high speed Direct drive first gear pure electric gear Direct drive third and fourth gear

[0087] It should be noted that the definitions of vehicle speed in Tables 2 and 3 can be set based on actual needs. For example, a speed range can be set as the medium speed range. When the vehicle speed is within the speed range, the hybrid vehicle is determined to be at the medium speed range; when the vehicle speed is below the speed range, the hybrid vehicle is determined to be at the low speed range; and when the vehicle speed is above the speed range, the hybrid vehicle is determined to be at the high speed range.

[0088] In practical applications, since ECVT gears need to achieve power splitting, a single output speed ratio will also negatively impact energy efficiency. In one specific implementation, the ECVT gears are configured as ECVT first gear and ECVT second gear, with the output speed ratio of ECVT first gear being greater than that of ECVT second gear; controlling the hybrid vehicle to operate in ECVT gear includes:

[0089] When the hybrid vehicle is operating in automatic mode, the control system operates the hybrid vehicle based on ECVT first gear. When the hybrid vehicle accelerates to a second speed threshold, it switches to ECVT second gear. Please refer to [link / reference]. Figure 5 , Figure 5 This is a shift map for automatic mode. The vertical dashed line in the diagram represents the shift curve for the ECVT gear. After the vehicle starts, you can select either ECVT gear 1 or pure electric mode based on the remaining battery power. In pure electric mode, the vehicle can shift to ECVT gear 1 as it accelerates, and then shift to ECVT gear 2 as it continues to accelerate. When downshifting, the vehicle maintains direct drive gear 3 based on vehicle speed and wheel torque requirements, downshifting when the vehicle reaches the shift line of the dashed curve. The initial gear configuration is ECVT gear 1, which helps to generate electricity promptly when parked. When starting with heavy throttle, using ECVT gear can start the engine to improve starting power. When starting with light throttle, the engine can be kept off. In pure electric mode, fuel is saved. At medium to high speeds, it supports rapid speed adjustment and shifting to direct drive gear. In automatic mode, when there is a high power demand at low speeds, the engine can be started in ECVT gear within the calibrated speed threshold of 20 km / h. When the speed exceeds 20 km / h, the vehicle can directly shift from ECVT gear 1 to direct drive gear 2 to improve power during acceleration.

[0090] When the hybrid vehicle is running in Sport mode, the hybrid vehicle is controlled to operate in first gear using the ECVT. Please refer to [link / reference]. Figure 6 , Figure 6 This is the shift map for Sport mode. Because the ECVT first gear has a higher output ratio, if the remaining battery power is low when starting, or if better output power is required, you can select the initial gear as ECVT first gear to obtain better starting performance.

[0091] When a hybrid vehicle is running in fuel-saving mode, it is controlled to drive in ECVT second gear. ECVT second gear has a higher output speed ratio, which can ensure that the hybrid vehicle has better fuel economy.

[0092] During gear shift control, the system can also implement shift control based on multiple sources of information, including environmental information (such as altitude, temperature, and wind resistance), road information (such as slope, congestion, or smooth traffic), predicted remaining battery power, battery discharge power, engine available power (affected by intake air temperature and altitude), predicted vehicle speed, and driving style. This shift control is executed through the energy management module, which adaptively optimizes the speed and power demand coverage range corresponding to the ECVT mode. Simultaneously, the speed selection point in ECVT mode is corrected based on environmental information, road information, and discharge power to improve wheel-end power and power generation capacity, thus covering extreme scenarios and customer driving needs. For example, it adjusts based on altitude; the higher the altitude, the higher the ECVT speed coverage and the higher the ECVT speed selection point. As the predicted remaining battery power gradually decreases, the ECVT speed selection point will adaptively increase when the road becomes an incline.

[0093] The energy management module designs and predicts corresponding values ​​for EV and direct drive modes based on vehicle speed, remaining battery power, power demand, and customer driving style learning. Within each mode, the enabling conditions for entering EV and direct drive modes are defined according to vehicle speed, respectively meeting fuel consumption and power target requirements. For example, in Sport mode, calibrable vehicle speed and wheel torque requirements are designed, allowing entry into EV mode at low speeds and prohibiting entry at high speeds to avoid insufficient power due to engine shutdown and insufficient high-speed drive motor capability at high speeds.

[0094] In practical applications, the performance of hybrid vehicles is primarily based on rules established for EV or series-parallel operation modes. Their energy-saving effect is significantly influenced by actual environmental or operating conditions and cannot be adaptively adjusted. Therefore, in one specific implementation, after controlling the hybrid vehicle to switch to direct drive mode, the method further includes:

[0095] Obtain congestion information for the route the hybrid vehicle is scheduled to travel on. During the journey, congestion information can be obtained in real-time via an online map. This information characterizes the congestion status of the route the hybrid vehicle will travel on, and can be represented by a congestion factor. For example, the congestion factor can be set to a value between 0 and 1; a higher value indicates more severe congestion. Based on the congestion information, configure the remaining battery power of the hybrid vehicle to a target battery level. The target battery level represents the battery level at which the hybrid vehicle can travel the route with minimal energy consumption. The target battery level can be set according to actual needs. For example, if the route is severely congested, a lower remaining battery level can be set under suitable battery conditions; if the traffic is relatively smooth, a higher remaining battery level can be set.

[0096] Because actual road conditions vary, applying the same threshold for gear shifting can lead to insufficient applicability. Therefore, in one specific implementation, after controlling the hybrid vehicle to switch to direct drive, the method further includes:

[0097] Acquire historical energy consumption data of the hybrid vehicle and navigation data of the route to be traveled. Historical energy consumption data represents the energy consumption of the hybrid vehicle on the already traveled route, and can be represented by energy consumption per 100 kilometers, such as electricity and fuel consumption per 100 km. Navigation data includes data on gradient, congestion factor, weather, etc. Input the historical energy consumption data and navigation data into a preset calculation model, and obtain the parameter thresholds for the hybrid vehicle to perform gear shifting actions based on the output of the calculation model. Please refer to [link to relevant documentation]. Figure 7 , Figure 7 The flowchart for adaptive gear shift control uses a fuzzy clustering algorithm as the computational model. This model calculates characteristic parameters such as the driver's average power demand, actual operating gear, average vehicle speed, and actual remaining battery power within a given time period based on navigation data from different scenarios, thus determining the predicted vehicle energy consumption. This is compared with historical energy consumption data from the vehicle's infotainment system. The parameter threshold corresponding to the data with lower energy consumption is output. These parameter thresholds are control thresholds for performing gear shifts, such as vehicle speed threshold, power threshold, and battery power threshold. The obtained parameter thresholds result in lower driving energy consumption when performing gear shifts under corresponding operating conditions. Therefore, the corresponding thresholds for performing gear shifts are updated based on these parameter thresholds.

[0098] Based on the same inventive concept as the control method, embodiments of the present invention also provide a shift control device for a hybrid vehicle. Please refer to [link to relevant documentation]. Figure 8 , Figure 8 This is a schematic diagram of the shift control device, which includes:

[0099] The first acquisition module 801 is used to acquire the wheel-end torque requirement and driving speed of the hybrid vehicle.

[0100] The first determining module 802 is used to determine whether the target state of switching to direct drive mode has been reached based on the wheel end torque demand and the vehicle speed. The direct drive mode is a mode in which both the drive motor and the engine of the hybrid vehicle output torque to the wheel end and lock the generator that is connected to the engine.

[0101] The first control module 803 is used to control the hybrid vehicle to switch to the direct drive mode when it is determined that the direct drive mode is to be switched.

[0102] The second control module 804 is used to determine that when switching to direct drive gear is not performed, the hybrid vehicle is controlled to drive in other drive gears, and when the hybrid vehicle reaches the target driving state, it is switched to direct drive gear.

[0103] In one optional embodiment, the direct drive gears include direct drive first gear, direct drive second gear, direct drive third gear, and direct drive fourth gear, and the output speed ratio of the direct drive gears decreases sequentially from direct drive first gear to direct drive fourth gear; the first control module includes:

[0104] The first acquisition submodule is used to acquire the current operating mode of the hybrid vehicle;

[0105] The first determining submodule is used to determine whether the driving speed is less than a first speed threshold when the current operating mode is automatic mode or fuel-saving mode.

[0106] The first switching submodule is used to switch the hybrid vehicle to direct drive second gear or direct drive third gear according to the wheel end torque demand and the vehicle speed when the driving speed is less than the first vehicle speed threshold.

[0107] The second switching submodule is used to switch the hybrid vehicle to direct drive fourth gear when the driving speed is not less than the first vehicle speed threshold.

[0108] The fourth switching submodule is used to switch the hybrid vehicle to direct drive first gear, direct drive second gear, or direct drive third gear according to the wheel end torque demand and driving speed when the current operating mode is sport mode.

[0109] In an optional embodiment, the control device further includes:

[0110] The second determining module is used to determine whether there is a risk of shift failure when switching to a direct drive gear based on the wheel end torque requirement, vehicle speed and preset shift MAP.

[0111] The third control module is used to control the hybrid vehicle to switch to direct drive mode when there is no risk of shift failure.

[0112] The fourth control module is used to keep the hybrid vehicle in the current drive gear when there is a risk of shift failure.

[0113] In one optional embodiment, other drive gears include a pure electric gear and an ECVT gear, wherein the ECVT gear is a gear in which both the drive motor and the engine output torque to the wheel ends, and the generator is not locked; the second control module includes:

[0114] The second acquisition submodule is used to acquire the remaining power of the power battery of the hybrid vehicle;

[0115] The judgment submodule is used to determine whether the remaining power is greater than the preset power threshold and whether the wheel end torque requirement is less than the preset torque threshold.

[0116] The first control submodule is used to control the hybrid vehicle to drive in pure electric mode when the remaining battery power is greater than the battery power threshold and the wheel end torque demand is less than the torque threshold.

[0117] The second control submodule is used to control the hybrid vehicle to drive in ECVT mode when the remaining battery power is not greater than the battery power threshold, or the wheel end torque requirement is not less than the torque threshold.

[0118] In one optional embodiment, the ECVT gears include ECVT first gear and ECVT second gear, wherein the output speed ratio of ECVT first gear is greater than the output speed ratio of ECVT second gear; the second control submodule includes:

[0119] The first control unit is used to control the hybrid vehicle to drive in first gear based on the ECVT when the hybrid vehicle is running in sport mode.

[0120] The second control unit is used to control the hybrid vehicle to drive in ECVT first gear when the hybrid vehicle is running in automatic mode, and to switch to ECVT second gear when the hybrid vehicle accelerates to the second vehicle speed threshold.

[0121] The third control unit is used to control the hybrid vehicle to drive in second gear based on ECVT when the hybrid vehicle is running in fuel-saving mode.

[0122] In an optional embodiment, the control device further includes:

[0123] The second acquisition module is used to acquire congestion information of the road to which the hybrid vehicle is to travel;

[0124] The configuration module is used to configure the remaining power of the hybrid vehicle's power battery to a target power level based on congestion information. The target power level is the power level at which the hybrid vehicle can pass through the road to be driven with minimal energy consumption.

[0125] In an optional embodiment, the control device further includes:

[0126] The third acquisition module is used to acquire historical energy consumption data of hybrid vehicles and navigation data of the road to be driven.

[0127] The input acquisition module is used to input historical energy consumption data and navigation data into a preset calculation model, and obtain the parameter threshold for the hybrid vehicle to perform gear shifting action based on the output of the calculation model.

[0128] The update module is used to update the corresponding threshold for performing a gear shift action based on the parameter threshold.

[0129] Based on the same inventive concept as the control method, embodiments of the present invention also provide an electronic device, including a processor and a memory, the memory being coupled to the processor, the memory storing instructions, which, when executed by the processor, cause the electronic device to perform the steps of any of the control methods.

[0130] Based on the same inventive concept as the control method, embodiments of the present invention also provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any one of the methods in the control method.

[0131] The technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0132] The shift control method acquires the wheel-end torque demand and vehicle speed of the hybrid vehicle. Based on these parameters, it determines whether the target state for switching to direct drive has been reached. Since direct drive is the gear where both the drive motor and engine of the hybrid vehicle output torque to the wheels and lock the generator connected to the engine, no power is allocated to the generator for power generation when driving the hybrid vehicle in direct drive. This satisfies basic power and fuel economy control indicators. When the hybrid vehicle meets the switching conditions for direct drive, it directly shifts to direct drive. If the switching conditions are not met, the hybrid vehicle is controlled to drive in other drive gears, and shifts to direct drive in a timely manner when the hybrid vehicle reaches the target driving state. This control method allows the hybrid vehicle to prioritize direct drive in different driving conditions. Direct drive has a higher response level, thus balancing power and fuel economy during hybrid vehicle operation.

[0133] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0134] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (modules, systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0135] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0136] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0137] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0138] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A shift control method for a hybrid vehicle, characterized in that, The method includes: Obtain the wheel-end torque requirement and driving speed of the hybrid vehicle; Based on the required torque at the wheel end and the vehicle speed, determine whether the target state of switching to direct drive gear has been reached. The direct drive gear is a gear in which both the drive motor and the engine of the hybrid vehicle output torque to the wheel end and lock the generator that is connected to the engine. If so, then control the hybrid vehicle to switch to the direct drive gear; If not, the hybrid vehicle is controlled to drive in other drive gears, and when the driving state of the hybrid vehicle reaches the target state, it is shifted to the direct drive gear. The other drive gears include pure electric gear and ECVT gear, wherein the ECVT gear is a gear in which both the drive motor and the engine output torque to the wheels, and the generator is not locked; controlling the hybrid vehicle to drive in other drive gears includes: Obtain the remaining charge of the power battery of the hybrid vehicle; Determine whether the remaining battery power is greater than a preset battery power threshold and whether the required torque at the wheel end is less than a preset torque threshold; If so, then control the hybrid vehicle to drive in the pure electric mode; If not, then control the hybrid vehicle to drive in the ECVT gear; The ECVT gears include ECVT first gear and ECVT second gear, wherein the output speed ratio of ECVT first gear is greater than the output speed ratio of ECVT second gear; controlling the hybrid vehicle to drive in the ECVT gears includes: When the hybrid vehicle is running in Sport mode, the hybrid vehicle is controlled to drive in first gear based on the ECVT. When the hybrid vehicle is running in automatic mode, the hybrid vehicle is controlled to drive in the first gear of the ECVT, and when the hybrid vehicle accelerates to the second speed threshold, it switches to the second gear of the ECVT. When the hybrid vehicle is operating in fuel-saving mode, the hybrid vehicle is controlled to drive in second gear based on the ECVT.

2. The shift control method for a hybrid vehicle according to claim 1, characterized in that, The direct drive gears include direct drive gear 1, direct drive gear 2, direct drive gear 3, and direct drive gear 4, and the output speed ratios of the direct drive gears decrease sequentially from direct drive gear 1 to direct drive gear 4; controlling the hybrid vehicle to switch to the direct drive gears includes: Obtain the current operating mode of the hybrid vehicle; When the current operating mode is automatic mode or fuel-saving mode, determine whether the driving speed is less than a first speed threshold. When the vehicle speed is less than the first vehicle speed threshold, the hybrid vehicle is switched to direct drive second gear or direct drive third gear according to the wheel end torque requirement and the vehicle speed. When the vehicle speed is not less than the first vehicle speed threshold, the hybrid vehicle is switched to the direct drive fourth gear; When the current operating mode is Sport mode, the hybrid vehicle is switched to direct drive first gear, direct drive second gear, or direct drive third gear according to the wheel end torque requirement and the vehicle speed.

3. The shift control method for a hybrid vehicle according to claim 1, characterized in that, Before controlling the hybrid vehicle to switch to the direct drive gear, the method further includes: Based on the wheel-end torque requirement, the vehicle speed, and the preset shift MAP, determine whether there is a risk of shift failure when switching the direct drive gear; If not, then control the hybrid vehicle to switch to the direct drive gear; If so, the hybrid vehicle is kept in the current drive gear.

4. The shift control method for a hybrid vehicle according to claim 1, characterized in that, After controlling the hybrid vehicle to switch to the direct drive gear, the method further includes: Obtain congestion information for the road where the hybrid vehicle is to travel; Based on the congestion information, the remaining charge of the hybrid vehicle's power battery is configured as a target charge, wherein the target charge is the charge corresponding to the hybrid vehicle's ability to pass through the road to be traveled with minimal energy consumption.

5. The shift control method for a hybrid vehicle according to claim 1, characterized in that, After controlling the hybrid vehicle to switch to the direct drive gear, the method further includes: Acquire historical energy consumption data and navigation data of the road to be traveled for the hybrid vehicle; The historical energy consumption data and the navigation data are input into a preset calculation model, and the parameter threshold for the hybrid vehicle to perform a gear shifting action is obtained based on the output of the calculation model. The corresponding threshold for performing the gear shift action is updated based on the parameter threshold.

6. A shift control device for a hybrid vehicle, characterized in that, The device includes: The first acquisition module is used to acquire the wheel-end torque requirement and driving speed of the hybrid vehicle; The first determining module is used to determine whether the target state of switching to direct drive gear has been reached based on the wheel end torque requirement and the vehicle speed. The direct drive gear is a gear in which both the drive motor and the engine of the hybrid vehicle output torque to the wheel end and lock the generator that is connected to the engine. The first control module is used to control the hybrid vehicle to switch to the direct drive gear when it is determined that the direct drive gear is to be switched. The second control module is used to determine that if the switching of the direct drive gear is not performed, the hybrid vehicle is controlled to drive in other drive gears, and the hybrid vehicle is switched to the direct drive gear when the driving state reaches the target state. Other drive modes include pure electric mode and ECVT mode. ECVT mode is where both the drive motor and engine output torque to the wheels, and the generator is not locked. The second control module includes: The second acquisition submodule is used to acquire the remaining power of the power battery of the hybrid vehicle; The judgment submodule is used to determine whether the remaining power is greater than the preset power threshold and whether the wheel end torque requirement is less than the preset torque threshold. The first control submodule is used to control the hybrid vehicle to drive in pure electric mode when the remaining battery power is greater than the battery power threshold and the wheel end torque demand is less than the torque threshold. The second control submodule is used to control the hybrid vehicle to drive in ECVT mode when the remaining battery power is not greater than the battery power threshold or the wheel end torque requirement is not less than the torque threshold. The ECVT gears include ECVT first gear and ECVT second gear, with the output speed ratio of ECVT first gear being greater than that of ECVT second gear; the second control submodule includes: The first control unit is used to control the hybrid vehicle to drive in first gear based on the ECVT when the hybrid vehicle is running in sport mode. The second control unit is used to control the hybrid vehicle to drive in ECVT first gear when the hybrid vehicle is running in automatic mode, and to switch to ECVT second gear when the hybrid vehicle accelerates to the second vehicle speed threshold. The third control unit is used to control the hybrid vehicle to drive in second gear based on ECVT when the hybrid vehicle is running in fuel-saving mode.

7. An electronic device, characterized in that, The device includes a processor and a memory, the memory being coupled to the processor, the memory storing instructions that, when executed by the processor, cause the electronic device to perform the steps of the method according to any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method described in any one of claims 1-5.

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