A multi-gear power constant pressure driving mode method for a hybrid vehicle

Abstract

The application discloses a kind of hybrid vehicle multi-gear power constant pressure driving mode methods, including, when UDC driving enters, the condition judgment of vehicle speed and fuel quantity is carried out to vehicle, and pre-control process strategy is matched;According to the pre-control process strategy matched, UDC driving power process control is carried out, and HCU power control is implemented;When UDC driving exits, vehicle is in UDC power generation driving mode, the state judgment is carried out to vehicle, and corresponding strategy is matched according to the judgment result.This method can be in hybrid vehicle under the limitation of battery capacity, without high-voltage battery intervention, through power control driving power and power generation power, multi-gear power constant pressure driving mode of just-in-time use.Improves the utilization rate of hybrid power system, also improves the robustness of whole vehicle system.

Description

Technical Field

[0001] This invention relates to the field of constant pressure driving technology, and in particular to a method for a multi-power constant pressure driving mode for hybrid vehicles. Background Technology

[0002] Hybrid electric vehicles (HEVs) are vehicles whose drive systems have two or more power sources, namely an internal combustion engine and electric power, with the vehicle's driving status provided by a single system or by a combination of these systems. The complex composition and high coupling of the power system in hybrid vehicles make them more prone to malfunctions that prevent them from driving, such as the battery having no allowable charging power and extremely low allowable discharging power at low temperatures, extremely low allowable discharging power when the battery is low, and battery malfunctions of level 4 or higher that prevent driving (not related to high voltage safety).

[0003] However, at this time, the internal combustion engine system and drive motor system of the hybrid vehicle can be used normally. If the hybrid vehicle cannot drive simply because of the battery, the hybrid system will not be able to perform its functions. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, this invention provides a method for a multi-level power constant voltage driving mode for hybrid vehicles. When the battery capacity of a hybrid vehicle is limited, it does not require the intervention of a high-voltage battery. By controlling the power of the drive power and the power generation power, the multi-level power constant voltage driving mode is available on demand, which improves the utilization rate of the hybrid power system and also improves the robustness of the whole vehicle system.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for a multi-level power constant pressure driving mode for hybrid vehicles, comprising:

[0007] When UDC driving mode is activated, the vehicle speed and fuel quantity are assessed, and a pre-control process strategy is matched. Based on the matched pre-control process strategy, UDC driving power process control is performed, and HCU power control is implemented. When UDC driving mode is deactivated, the vehicle is in UDC power generation driving mode. The vehicle status is assessed, and a corresponding strategy is matched based on the assessment result.

[0008] As a preferred embodiment of the hybrid vehicle multi-power constant pressure driving mode method described in this invention, the condition judgment of vehicle speed and fuel quantity includes: when the vehicle speed is less than or equal to the calibration threshold and the fuel quantity is greater than the calibration threshold, the low temperature scenario judgment of condition 1 is performed.

[0009] The low-temperature scenario judgment under condition 1 includes judging the non-safety fault scenario under condition 2 when the real-time discharge power of the battery pack is ≥ threshold 2, the real-time charging power of the battery pack is ≤ threshold 3 and the ambient temperature is < threshold.

[0010] The battery non-safety fault scenario judgment under condition 2 includes the following: when the battery pack fault level = 4, the current state is determined to be a discharge standard level 3 warning; when the battery pack fault level = 5, the current state is determined to be a battery stop request; when the battery pack fault level = 9, the current state is determined to be a battery stop charging request; when the battery pack fault level = 8, the system determines that the battery non-safety fault is a charging standard level 3 warning and there is no P1 motor or engine prohibition fault.

[0011] As a preferred embodiment of the multi-power constant-pressure driving mode method for hybrid vehicles described in this invention, the condition judgment of vehicle speed and fuel quantity further includes: when the current state of the vehicle does not meet conditions 1 and 2, the system notifies the vehicle not to enter the constant-pressure mode; if the battery is not at a low temperature and the discharge and charging allowable power is normal, the vehicle maintains the current mode; if a battery fault occurs and the P1 engine has a failure to start, a warning is issued through the vehicle malfunction indicator lamp; if the battery is not faulty and the P1 engine is not faulty, the vehicle maintains the current mode; if the P1 engine has a failure to start, the corresponding fault procedure is entered.

[0012] As a preferred embodiment of the multi-power constant pressure driving mode method for hybrid vehicles described in this invention, the pre-control process includes pre-control process 1 and pre-control process 2; when the vehicle state meets conditions 1 and 2, the system performs pre-control process 1.

[0013] The pre-control process 1 includes controlling P1 to start the engine speed and stabilize the engine speed to 1400 rpm; if the current state of the vehicle meets the conditions of the pre-control process 1, the system requests the engine start process, obtains the engine working state and mode, and stabilizes the current engine speed to 1400±50 rpm. At the same time, the system requests the MCU to disable its operation and feeds back the MCU working state as unprepared.

[0014] After passing through pre-control process 1, the vehicle enters pre-control process 2; the pre-control process 2 includes disabling DC-DC enable, requesting MCU to diasble and simultaneously sending the UDC mode flag.

[0015] If the vehicle fails to complete pre-control process 1 and pre-control process 2, the system determines that the vehicle has failed to enter constant pressure mode, issues an instrument prompt, and illuminates the vehicle's fault lights.

[0016] When the vehicle completes pre-control process 1 and pre-control process 2, it requests the main positive and main negative high voltage relays of the battery pack to be disconnected, requiring the battery pack current to be less than 10A. At the same time, under low temperature, the battery controls the heating relay to remain connected according to the UDC flag bit.

[0017] As a preferred embodiment of the multi-power constant-pressure driving mode method for hybrid vehicles described in this invention, the pre-control process further includes: if the main positive and main negative high-voltage relays of the battery pack fail to disconnect, the constant-pressure mode fails to enter, the instrument panel will display a warning, and the vehicle malfunction indicator lamp will be illuminated; if the main positive and main negative high-voltage relays of the battery pack successfully disconnect, the UDC driving control process will be entered, the P1 MCU feedback mode will be adjusted to the enabled voltage mode, the PSMCU will control the generator speed to raise the bus voltage to above 240V and below 420V, the DC-DC operating state will be adjusted to enable, the voltage output will be 14V, and the current will be ≥0.01A. At the same time, the engine mode will be idle mode and the starting process will not involve any changes, the clutch will remain disengaged, the P3 MCU mode request will be set to torque mode, the UDC mode flag will be sent out, the water heating PTC will be configured to have the PTC relay closed, the constant-pressure mode will enter the control process, and the instrument panel will display "Battery preheating".

[0018] As a preferred embodiment of the multi-power constant-pressure driving mode method for hybrid vehicles described in this invention, the UDC driving power process control includes: real-time calculation of the power demand of vehicle accessories; outputting the actual accessory power demand after passing through the vehicle limiting module; calculating and outputting the power demand of vehicle accessories; limiting the maximum allowable vehicle speed in the UDC mode to a calibrated value; performing drive demand power control; limiting the maximum opening of the driver's accelerator pedal to a calibrated value; ensuring that the driver's required torque is fully allocated to the drive motor; converting and outputting the driver's required torque after pedal acquisition and vehicle capacity limitation; converting the power requested by the P3 drive motor to the torque requested by the P3 drive motor; simultaneously performing driving power control, including the power requested by the P3 drive motor plus the power demand of vehicle accessories, the required power being a real-time changing power; performing rate slope module and UDC demand power; the UDC demand power is the power demand of P1 generator, the change gradient is ≥ threshold 4, after processing, the P1 generator speed and torque are sent to the MCU; the engine generator torque is sent to the engine; the engine and motor have three generator speeds; calibration ensures that the torque of the engine and motor in the gear is within the sustainable load range and energy recovery is prohibited throughout the process.

[0019] As a preferred embodiment of the multi-power constant pressure driving mode method for hybrid vehicles described in this invention, the HCU power control includes: setting a calibration time threshold; within the time threshold range, regardless of how many times the driver presses the accelerator pedal, calculating the latest accelerator demand within the time period and performing drive demand power control; limiting the maximum calibrated value of the driver's accelerator pedal opening; ensuring that the driver's required torque is fully allocated to the drive motor; converting and outputting the driver's required torque after pedal acquisition and vehicle capacity limitation; outputting the P3 drive motor requested power; calculating the high and low voltage accessory power requirements of DC-DC, AC, and PTC through the vehicle accessory power demand calculation module; jointly outputting the required power with the drive demand power control; and back-calculating the drive motor requested torque and engine generator torque based on vehicle speed information; back-calculating the P1 generator torque based on the speed ratio; and updating and outputting the initial stage P3 drive motor requested torque and engine generator torque after determining that the rate of change is greater than the threshold; wherein, the rate of change of required power is limited by a slope.

[0020] As a preferred embodiment of the multi-power constant-pressure driving mode method for hybrid vehicles described in this invention, the UDC driving exit includes: when the vehicle is in the UDC power generation driving mode pre-control process 2 and thereafter, performing a mode exit judgment. The mode exit judgment pass condition is that the real-time discharge power of the battery pack > the recovery threshold or the allowed charging power of the battery pack > the recovery threshold, and the battery pack fault is recovered. If the judgment passes and the vehicle speed < the threshold, then exit process control 2 is executed, prohibiting the P1 and P3 engines from working and prohibiting DC power from working. The vehicle speed threshold is a calibrated value with an initial value of 0. After executing exit process control 2, exit process control 3 is entered, and the vehicle performs a normal high-voltage process. If the judgment passes and the key status is OFF, then exit process control 2 is executed.

[0021] If the judgment fails, an abnormal exit condition judgment is made for thermal runaway, collision, P1 or engine failure. If the abnormal exit condition judgment is passed, exit process control 4 is executed, emergency power is cut off, and the vehicle malfunction indicator light is displayed. If the abnormal exit condition judgment fails, the UDC power generation driving mode is maintained.

[0022] A computer device includes a memory and a processor, the memory storing a computer program, characterized in that the processor executes the computer program to implement a method for a hybrid vehicle with multiple power constant pressure driving modes.

[0023] A computer-readable storage medium having a computer program stored thereon, characterized in that, when the computer program is executed by a processor, it implements the steps of a method for a hybrid vehicle with multiple power constant pressure driving modes.

[0024] The beneficial effects of this invention are as follows: This invention designs a multi-level constant-voltage driving mode for hybrid vehicles under battery capacity constraints, eliminating the need for high-voltage battery intervention and enabling on-demand use of drive and generator power through power control. This improves the utilization rate of the hybrid system and enhances the robustness of the entire vehicle system. This invention proposes a process that solves the driving problem of hybrid vehicles under battery-limited conditions by disconnecting the high-voltage relay of the battery pack and using a multi-level constant-voltage mode process. Simultaneously, by designing a precise on-demand control process for generator and drive power, it coordinates and controls the constant-voltage output of the engine and generator, resolving the overvoltage problem of the motor controller. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the UDC driving entry process for a hybrid vehicle multi-power constant pressure driving mode method provided in one embodiment of the present invention.

[0027] Figure 2 This is a schematic diagram of the UDC driving entry (continued 1) process of a method for multi-level power constant pressure driving mode of a hybrid vehicle provided in an embodiment of the present invention.

[0028] Figure 3 This is a schematic diagram of the UDC driving entry (continued 2) process of a hybrid vehicle multi-power constant pressure driving mode method provided in an embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram of the HCU power control process for a hybrid vehicle's multi-power constant pressure driving mode method, provided as an embodiment of the present invention.

[0030] Figure 5 This is a schematic diagram of the UDC driving exit process of a hybrid vehicle multi-power constant pressure driving mode method provided in an embodiment of the present invention. Detailed Implementation

[0031] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0032] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0033] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0034] This invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0035] Furthermore, in the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In addition, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0036] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] Example 1

[0038] Reference Figures 1-5 This is the first embodiment of the present invention, which provides a method for a multi-level power constant pressure driving mode for a hybrid vehicle, including:

[0039] S1: When the UDC vehicle enters, the vehicle speed and fuel quantity are assessed, and a pre-control process strategy is matched.

[0040] The conditional judgment of vehicle speed and fuel quantity includes, when the vehicle speed is less than or equal to the calibrated threshold and the fuel quantity is greater than the calibrated threshold, the low-temperature scenario judgment of condition 1 is performed.

[0041] The low-temperature scenario judgment under condition 1 includes judging the non-safety fault scenario under condition 2 when the real-time discharge power of the battery pack is ≥ threshold 2, the real-time charging power of the battery pack is ≤ threshold 3 and the ambient temperature is < threshold.

[0042] The battery non-safety fault scenario judgment under condition 2 includes the following: when the battery pack fault level = 4, the current state is determined to be a discharge standard level 3 warning; when the battery pack fault level = 5, the current state is determined to be a battery stop request; when the battery pack fault level = 9, the current state is determined to be a battery stop charging request; when the battery pack fault level = 8, the system determines that the battery non-safety fault is a charging standard level 3 warning and there is no P1 motor or engine prohibition fault.

[0043] The conditional judgment of vehicle speed and fuel quantity also includes: when the current state of the vehicle does not meet conditions 1 and 2, the system notifies the vehicle not to enter constant pressure mode; if the battery is not at low temperature and the discharge and charging allowable power is normal, the vehicle maintains the current mode; if a battery fault occurs and the P1 engine has a failure to start, a warning is issued through the vehicle malfunction indicator lamp; if the battery is not faulty and the P1 engine is not faulty, the vehicle maintains the current mode; if the P1 engine has a failure to start, the corresponding fault procedure is entered.

[0044] S2: Based on the matched pre-control process strategy, perform UDC driving power process control and implement HCU power control.

[0045] The pre-control process includes pre-control process 1 and pre-control process 2; when the vehicle state meets conditions 1 and 2, the system performs pre-control process 1;

[0046] The pre-control process 1 includes controlling P1 to start the engine speed and stabilize the engine speed to 1400 rpm; if the current state of the vehicle meets the conditions of the pre-control process 1, the system requests the engine start process, obtains the engine working state and mode, and stabilizes the current engine speed to 1400±50 rpm. At the same time, the system requests the MCU to disable its operation and feeds back the MCU working state as unprepared.

[0047] After passing through pre-control process 1, the vehicle enters pre-control process 2; the pre-control process 2 includes disabling DC-DC enable, requesting MCU to diasble and simultaneously sending the UDC mode flag.

[0048] If the vehicle fails to complete pre-control process 1 and pre-control process 2, the system determines that the vehicle has failed to enter constant pressure mode, issues an instrument prompt, and illuminates the vehicle's fault lights.

[0049] When the vehicle completes pre-control process 1 and pre-control process 2, it requests the main positive and main negative high voltage relays of the battery pack to be disconnected, requiring the battery pack current to be less than 10A. At the same time, under low temperature, the battery controls the heating relay to remain connected according to the UDC flag bit.

[0050] The pre-control process also includes the following steps: if the main positive and main negative high-voltage relays of the battery pack fail to disconnect, the constant voltage mode will fail to enter, the instrument panel will display a warning, and the vehicle's fault light will illuminate; if the main positive and main negative high-voltage relays of the battery pack successfully disconnect, the UDC driving control process will begin, the P1 MCU feedback mode will be adjusted to the enabled voltage mode, the PSMCU will control the generator speed to raise the bus voltage to above 240V and below 420V, the DC-DC converter will be enabled, the voltage output will be 14V, and the current will be ≥0.01A. At the same time, the engine mode will be idle mode and the starting process will not involve any changes. The clutch will remain disengaged, the P3 MCU mode will request to be torque mode, the UDC mode flag will be sent out, the water heating PTC will be configured to have the PTC relay closed, the constant voltage mode will enter the control process, and the instrument panel will display "Battery preheating".

[0051] The UDC driving power process control includes: real-time calculation of the vehicle accessory power demand; outputting the actual accessory power demand after passing through the vehicle limiting module; calculating and outputting the vehicle accessory power demand; limiting the maximum allowable vehicle speed in the UDC mode to a calibrated value; controlling the drive demand power; limiting the maximum opening of the driver's accelerator pedal to a calibrated value; ensuring that the driver's required torque is fully allocated to the drive motor; converting and outputting the driver's required torque after pedal acquisition and vehicle capacity limitation; converting the P3 drive motor's requested power to the P3 drive motor's requested torque; simultaneously performing driving power control, including the P3 drive motor's requested power plus the vehicle accessory power demand, with the required power being a real-time changing power; performing rate slope module and UDC demand power; the UDC demand power is the P1 generator power demand, with a change gradient ≥ threshold 4; after processing, sending the P1 generator speed and torque to the MCU; sending the engine generator torque to the engine; setting the engine and motor to three generator speeds; calibrating to ensure that the engine and motor torques in the gears are within the sustainable load range and prohibiting energy recovery throughout the process.

[0052] The HCU power control includes setting a calibration time threshold. Within the time threshold range, regardless of how many times the driver presses the accelerator, the drive demand power control is calculated based on the latest accelerator demand within the current time period. This limits the maximum calibrated value of the driver's accelerator pedal opening, ensuring that all the driver's required torque is allocated to the drive motor. The driver's required torque, after being acquired from the pedal and limited by the vehicle's overall capacity, is converted and output, resulting in the output of the P3 drive motor requested power. The power demand of high and low voltage accessories (DCCDC, AC, PTC) is calculated through the vehicle accessory power demand calculation module and output together with the drive demand power control. The drive motor requested torque and engine generator torque are calculated back based on the vehicle speed information. The P1 generator torque is calculated back based on the speed ratio. After determining that the rate of change is greater than the threshold, the initial stage P3 drive motor requested torque and engine generator torque are updated and output. The rate of change of required power is limited by a slope.

[0053] S3: When UDC driving mode is exited, the vehicle enters UDC power generation driving mode. The vehicle status is determined, and the corresponding strategy is matched according to the determination result.

[0054] The UDC driving exit includes, when the vehicle is in the UDC power generation driving mode pre-control process 2 and thereafter, performing a mode exit judgment. The mode exit judgment pass condition is that the real-time discharge power of the battery pack > the recovery threshold or the allowed charging power of the battery pack > the recovery threshold, and the battery pack fault is recovered. If the judgment passes and the vehicle speed < the threshold, then exit process control 2 is executed, prohibiting the P1 and P3 engines from working and prohibiting DC operation. The vehicle speed threshold is a calibrated value with an initial value of 0. After executing exit process control 2, exit process control 3 is entered, and the whole vehicle performs the normal high voltage process. If the judgment passes and the key status is OFF, then exit process control 2 is executed.

[0055] If the judgment fails, an abnormal exit condition judgment is made for thermal runaway, collision, P1 or engine failure. If the abnormal exit condition judgment is passed, exit process control 4 is executed, emergency power is cut off, and the vehicle malfunction indicator light is displayed. If the abnormal exit condition judgment fails, the UDC power generation driving mode is maintained.

[0056] Example 2

[0057] Reference Figure 3 As an embodiment of the present invention, a method for a multi-level power constant pressure driving mode for hybrid vehicles is provided. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through experiments.

[0058] During the UDC driving power control process, the three generator speeds (engine and motor) are calibrated to ensure that the torque of the engine and motor at each speed is within the sustainable load range. Specific data are detailed in the table below:

[0059] Table 1 UDC Operating Condition Power Analysis Table

[0060]

[0061] Example 3

[0062] The third embodiment of the present invention differs from the first two embodiments in that:

[0063] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0064] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

[0065] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented 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. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0066] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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 processor, 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... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0067] 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.

[0068] 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.

[0069] Although preferred embodiments of this application 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 the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0070] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for a multi-level power constant-pressure driving mode for hybrid vehicles, characterized in that: include, When the UDC vehicle enters, the vehicle speed and fuel quantity are assessed, and a pre-control process strategy is matched accordingly. Based on the matched pre-control process strategy, perform UDC driving power process control and implement HCU power control; When UDC driving mode is exited, the vehicle enters UDC power generation driving mode. The vehicle status is determined, and the corresponding strategy is matched according to the determination result. The pre-control process includes pre-control process 1 and pre-control process 2; when the vehicle state meets conditions 1 and 2, the system performs pre-control process 1; The pre-control process 1 includes controlling P1 to start the engine speed and stabilize the engine speed to 1400 rpm; if the current state of the vehicle meets the conditions of the pre-control process 1, the system requests the engine start process, obtains the engine working state and mode, and stabilizes the current engine speed to 1400±50 rpm. At the same time, the system requests the MCU to disable its operation and feeds back the MCU working state as unprepared. After passing through pre-control process 1, the vehicle enters pre-control process 2; the pre-control process 2 includes disabling DC-DC enable, requesting MCU to diasble and simultaneously sending the UDC mode flag. If the vehicle fails to complete pre-control process 1 and pre-control process 2, the system determines that the vehicle has failed to enter constant pressure mode, issues an instrument prompt, and illuminates the vehicle's fault lights. When the vehicle completes pre-control process 1 and pre-control process 2, it requests the main positive and main negative high voltage relays of the battery pack to be disconnected, requiring the battery pack current to be less than 10A. At the same time, under low temperature, the battery controls the heating relay to remain connected according to the UDC flag bit. The pre-control process also includes the following steps: if the main positive and main negative high-voltage relays of the battery pack fail to disconnect, the constant voltage mode will fail to enter, the instrument panel will display a warning, and the vehicle's fault light will illuminate; if the main positive and main negative high-voltage relays of the battery pack successfully disconnect, the UDC driving control process will begin, the P1 MCU feedback mode will be adjusted to the enabled voltage mode, the PSMCU will control the generator speed to raise the bus voltage to above 240V and below 420V, the DC-DC converter will be enabled, the voltage output will be 14V, and the current will be ≥0.01A. At the same time, the engine mode will be idle mode and the starting process will not involve any changes. The clutch will remain disengaged, the P3 MCU mode will request to be torque mode, the UDC mode flag will be sent out, the water heating PTC will be configured to have the PTC relay closed, the constant voltage mode will enter the control process, and the instrument panel will display "Battery preheating".

2. The method for a multi-level power constant pressure driving mode for a hybrid vehicle as described in claim 1, characterized in that: The conditional judgment of vehicle speed and fuel quantity includes, when the vehicle speed is less than or equal to the calibrated threshold and the fuel quantity is greater than the calibrated threshold, the low-temperature scenario judgment of condition 1 is performed. The low-temperature scenario judgment under condition 1 includes judging the non-safety fault scenario under condition 2 when the real-time discharge power of the battery pack is ≥ threshold 2, the real-time charging power of the battery pack is ≤ threshold 3 and the ambient temperature is < threshold. The judgment of non-safety fault scenarios of the battery in condition 2 includes determining the current state as a discharge standard level 3 warning when the battery pack fault level = 4. When the battery pack fault level is 5, the system determines the current status as a battery shutdown request. When the battery pack fault level is 9, the system determines the current status as a battery charging stop request; when the battery pack fault level is 8, the system determines the battery non-safety fault as a national standard level 3 warning for charging and without a P1 motor or engine prohibition fault.

3. The method for a multi-level power constant pressure driving mode for a hybrid vehicle as described in claim 2, characterized in that: The conditional judgment of vehicle speed and fuel quantity also includes: when the current state of the vehicle does not meet conditions 1 and 2, the system notifies the vehicle not to enter constant pressure mode; if the battery is not at low temperature and the discharge and charging allowable power is normal, the vehicle maintains the current mode; if a battery fault occurs and the P1 engine has a failure to start, a warning is issued through the vehicle malfunction indicator lamp; if the battery is not faulty and the P1 engine is not faulty, the vehicle maintains the current mode; if the P1 engine has a failure to start, the corresponding fault procedure is entered.

4. The method for a multi-level power constant pressure driving mode for a hybrid vehicle as described in claim 3, characterized in that: The UDC driving power process control includes: real-time calculation of the vehicle accessory power demand; outputting the actual accessory power demand after passing through the vehicle limiting module; calculating and outputting the vehicle accessory power demand; limiting the maximum allowable vehicle speed in the UDC mode to a calibrated value; controlling the drive demand power; limiting the maximum opening of the driver's accelerator pedal to a calibrated value; ensuring that the driver's required torque is fully allocated to the drive motor; converting and outputting the driver's required torque after pedal acquisition and vehicle capacity limitation; converting the P3 drive motor's requested power to the P3 drive motor's requested torque; simultaneously performing driving power control, including the P3 drive motor's requested power plus the vehicle accessory power demand, with the required power being a real-time changing power; performing rate slope module and UDC demand power; the UDC demand power is the P1 generator power demand, with a change gradient ≥ threshold 4; after processing, sending the P1 generator speed and torque to the MCU; sending the engine generator torque to the engine; setting the engine and motor to three generator speeds; calibrating to ensure that the engine and motor torques in the gears are within the sustainable load range and prohibiting energy recovery throughout the process.

5. The method for a multi-level power constant pressure driving mode for a hybrid vehicle as described in claim 4, characterized in that: The HCU power control includes setting a calibration time threshold. Within the time threshold range, regardless of how many times the driver presses the accelerator, the drive demand power control is calculated based on the latest accelerator demand within the current time period. This limits the maximum calibrated value of the driver's accelerator pedal opening, ensuring that all the driver's required torque is allocated to the drive motor. The driver's required torque, after being acquired from the pedal and limited by the vehicle's overall capacity, is converted and output, resulting in the output of the P3 drive motor requested power. The power demand of high and low voltage accessories (DCCDC, AC, PTC) is calculated through the vehicle accessory power demand calculation module and output together with the drive demand power control. The drive motor requested torque and engine generator torque are calculated back based on the vehicle speed information. The P1 generator torque is calculated back based on the speed ratio. After determining that the rate of change is greater than the threshold, the initial stage P3 drive motor requested torque and engine generator torque are updated and output. The rate of change of required power is limited by a slope.

6. The method for a multi-level power constant pressure driving mode for a hybrid vehicle as described in claim 5, characterized in that: The UDC driving exit includes, when the vehicle is in the UDC power generation driving mode pre-control process 2 and thereafter, performing a mode exit judgment. The mode exit judgment pass condition is that the real-time discharge power of the battery pack > the recovery threshold or the allowed charging power of the battery pack > the recovery threshold, and the battery pack fault is recovered. If the judgment passes and the vehicle speed < the threshold, then exit process control 2 is executed, prohibiting the P1 and P3 engines from working and prohibiting DC operation. The vehicle speed threshold is a calibrated value with an initial value of 0. After executing exit process control 2, exit process control 3 is entered, and the whole vehicle performs the normal high voltage process. If the judgment passes and the key status is OFF, then exit process control 2 is executed. If the judgment fails, an abnormal exit condition judgment is made for thermal runaway, collision, P1 or engine failure. If the abnormal exit condition judgment is passed, exit process control 4 is executed, emergency power is cut off, and the vehicle malfunction indicator light is displayed. If the abnormal exit condition judgment fails, the UDC power generation driving mode is maintained.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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