A hybrid vehicle pressure relief control strategy and system

Abstract

The present invention discloses a hybrid vehicle pressure relief control strategy and system, comprising: obtaining the pressure value in the intake manifold when the engine surges based on engine parameters, setting the pressure value as a safety pressure value of the intake manifold; a vehicle controller real-time monitoring the actual pressure value of the intake manifold, and determining that the engine is in a surge state when the actual pressure value of the intake manifold is greater than the safety pressure value; the vehicle controller reduces the engine torque to a target torque value based on filter control to reduce the engine surge; when the engine surges, the present invention slowly reduces the engine torque value through a filter control method, so that the engine in the surge state can leave the surge interval, thereby shortening the surge time of the surge engine, and achieving the technical effect of eliminating surge when the pressure relief valve is removed.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid vehicles, and in particular to a hybrid vehicle pressure relief control strategy and system. Background Art

[0002] A hybrid vehicle is a vehicle equipped with two or more power sources. The hybrid vehicles usually referred to are generally oil-electric hybrid vehicles, which use traditional internal combustion engines and electric motors as power sources.

[0003] The engine of a traditional car generally needs to be equipped with a pressure relief valve between the compressor and the throttle, so that after the driver releases the accelerator pedal, when the torque drops rapidly, the high-pressure gas in the intake pipe after the boost is returned to the intake pipe in front of the supercharger or compressor through the pressure relief valve, so as to prevent the high-pressure gas from impacting the supercharger or compressor in the reverse direction when the intake flow rate drops rapidly after the throttle is quickly closed, causing the supercharged gas to vibrate the supercharger or compressor turbine blades, that is, generating supercharger or compressor surge; for the supercharger, surge is not allowed to occur, because once surge occurs, it will cause the compressor to work unstably, the air flow flowing through the compressor will begin to pulsate strongly, causing the compressor to vibrate strongly, and may damage the compressor hardware.

[0004] The pressure relief valve will generate noise when working, affecting driving comfort. Canceling the pressure relief valve will affect the normal driving of the car. However, since hybrid vehicles can use engines or electric motors to drive the car forward, how to avoid surging while maintaining normal driving of the car when canceling the pressure relief valve has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a hybrid vehicle pressure relief control strategy and system to solve the problem in the prior art of how to avoid surge and maintain normal driving of the vehicle when the pressure relief valve is removed.

[0006] To achieve the above-mentioned purpose, the technical solution of a hybrid vehicle pressure relief control strategy of the present invention is:

[0007] Acquiring a pressure value in the intake manifold when surging occurs based on engine parameters, and setting the pressure value as a safety pressure value of the intake manifold;

[0008] The automobile controller monitors the actual pressure value of the intake manifold in real time, and when the actual pressure value of the intake manifold is greater than the safety pressure value, it is determined that the engine is in a surging state;

[0009] The vehicle controller reduces the engine torque to a target torque value based on filtering control to alleviate engine surge.

[0010] Furthermore, the vehicle controller reduces the torque of the engine, including:

[0011] Acquire a first difference between the engine torque value and the target torque value;

[0012] increasing the torque of the electric motor based on the first difference;

[0013] The engine torque is reduced to the target torque value, and the heat energy generated by the engine combustion is consumed by using the vehicle components.

[0014] Furthermore, the heat energy generated by engine combustion is consumed by using vehicle components, including:

[0015] The vehicle controller obtains the current maximum allowable recovery energy of the power battery and the current heat energy of the engine converted by the generator into electrical energy, and calculates the second difference between the two;

[0016] If the second difference is greater than zero, the engine transfers all heat energy to the generator to generate electricity;

[0017] If the second difference is not greater than zero, the engine transfers a portion of the heat energy to the PTC for heat dissipation, and transfers another portion of the heat energy to the generator for power generation.

[0018] Furthermore, if after the engine transfers part of the heat energy to the PTC for heat dissipation, the current maximum allowable recovery energy of the power battery is still less than or equal to the generator converting all the current heat energy of the engine into electrical energy, the working range of the generator is adjusted to the low efficiency zone.

[0019] Furthermore, if the working range of the generator is adjusted to the low-efficiency zone, if the current maximum allowable recovery energy of the power battery is still less than or equal to the current thermal energy of the engine converted into electrical energy by the generator, the engine is shut down.

[0020] Furthermore, the working range of the generator is adjusted to the low efficiency range, including:

[0021] A generator efficiency MAP table is obtained, and the rotation speed and output power of the generator are adjusted based on the MAP table to be in a low efficiency zone.

[0022] Further, reducing the engine torque to the target torque value includes:

[0023] Obtaining a correspondence between an engine operating mode, an engine torque value and a torque filter coefficient, and establishing a filter table based on the correspondence;

[0024] The current engine operating mode is obtained, the torque filter coefficient is set based on the current operating mode, and the engine is filtered and controlled based on the torque filter coefficient to reduce the engine torque to the target torque value.

[0025] Furthermore, the corresponding relationship between the engine operating condition, the engine torque value and the filter coefficient is obtained, including:

[0026] Get the current working mode of the engine;

[0027] Determining a first filter coefficient based on a current operating mode of the engine;

[0028] Get the current working mode of the motor;

[0029] Determining a second filter coefficient based on the current operating mode of the motor;

[0030] If the first filter coefficient is less than the second filter coefficient, setting the first filter coefficient to the torque filter coefficient;

[0031] If the first filter coefficient is greater than the second filter coefficient, the second filter coefficient is set as the torque filter coefficient.

[0032] Furthermore, the engine operating mode includes a working mode and a zero torque mode.

[0033] On the other hand, the present invention further provides a hybrid vehicle pressure relief control system, which is used to implement a hybrid vehicle pressure relief control strategy in the above technical solution, and the system includes:

[0034] A monitoring module, used to monitor the actual pressure value in the intake manifold and the torque value of the engine;

[0035] A calculation module, used to calculate a first difference between the safety pressure value and the actual pressure value, and a second difference between the current maximum allowable recovery energy of the power battery and the electric energy obtained by the generator converting all the current heat energy of the engine;

[0036] A torque adjustment module, used for adjusting the torque value of the engine;

[0037] The generator adjustment module is used to adjust the working range of the generator.

[0038] Compared with the prior art, the beneficial effects of the present invention are at least as follows:

[0039] 1. The present invention first obtains the safety pressure value in the intake manifold when the engine surges through experiments, and monitors the actual pressure value in the intake manifold in real time, and compares the actual pressure value with the safety pressure value in the intake manifold, so as to determine whether the engine in this state has surged; when the engine surges, the torque value of the engine is slowly reduced by a filtering control method, so that the engine in the surge state can leave the surge range, thereby shortening the surge time of the surge engine, and achieving the technical effect of eliminating surge without removing the pressure relief valve.

[0040] 2. After reducing the engine torque, since the gas in the intake manifold will still enter the engine, the engine will generate excess heat when consuming this part of the gas. If it is not consumed in time, it will cause the engine to overheat; therefore, the heat generated by the engine is used to generate electricity for the generator, and the excess heat is transferred to the PTC, and the water temperature of the water circuit in the PTC is heated to an allowable range, thereby achieving the purpose of consuming engine heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of a flow chart of a hybrid vehicle pressure relief control strategy according to the present invention;

[0042] Figure 2 The figure is a schematic diagram of a process of reducing the torque of an engine by the automobile controller of the present invention. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0044] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first xx script may be referred to as a second xx script, and similarly, a second xx script may be referred to as a first xx script.

[0045] like Figure 1 and Figure 2 As shown, a hybrid vehicle pressure relief control strategy includes:

[0046] S1. Acquire a pressure value in the intake manifold when surging occurs based on engine parameters, and set the pressure value as a safety pressure value of the intake manifold;

[0047] S2. The vehicle controller monitors the actual pressure value of the intake manifold in real time. When the actual pressure value of the intake manifold is greater than the safety pressure value, it is determined that the engine is in a surging state;

[0048] S3, the vehicle controller filter control reduces the engine torque to the target torque value to reduce the engine surge.

[0049] The present invention first obtains the safety pressure value in the intake manifold when the engine surges through experiments, and monitors the actual pressure value in the intake manifold in real time, and compares the actual pressure value with the safety pressure value in the intake manifold, so as to determine whether the engine in this state has surged; when the engine surges, the torque value of the engine is slowly reduced through a filtering control method, so that the engine in the surge state can leave the surge range, thereby shortening the surge time of the surge engine, and achieving the technical effect of eliminating surge without removing the pressure relief valve.

[0050] In this embodiment, further, the vehicle controller reduces the torque of the engine, including:

[0051] S31, obtaining a first difference between the engine torque value and the target torque value;

[0052] S32, increasing the torque of the motor based on the first difference;

[0053] S33: reducing the engine torque to the target torque value, and using vehicle components to consume heat energy generated by engine combustion.

[0054] Reducing the engine torque will inevitably affect the driving of the car. However, since the hybrid car contains an electric motor, after the engine torque drops, the electric motor can be started and the torque of the electric motor can be increased to meet the driver's driving needs.

[0055] In this embodiment, the heat energy generated by engine combustion is consumed by using vehicle components, including:

[0056] The vehicle controller obtains the current maximum allowable recovery energy of the power battery and the current heat energy of the engine converted by the generator into electrical energy, and calculates the second difference between the two;

[0057] If the second difference is greater than zero, the engine transfers all the heat energy to the generator to generate electricity;

[0058] If the second difference is not greater than zero, the engine transfers part of the heat energy to the PTC for heat dissipation, and transfers the other part of the heat energy to the generator for power generation.

[0059] After reducing the engine torque, since the gas in the intake manifold will still enter the engine, the engine will generate excess heat when consuming this part of the gas. If it is not consumed in time, it will cause the engine to overheat; therefore, by obtaining the current maximum allowable recovery energy of the battery, and the generator converting all the current thermal energy of the engine into electrical energy, and obtaining the second difference between the two, when the second difference is greater than 0, it indicates that the heat generated by the engine can be fully used to generate electricity by the generator, and this part of the electricity can be completely recovered by the power battery, thereby achieving the purpose of consuming the engine heat; when the second difference is less than 0, it indicates that this part of the electricity cannot be completely absorbed by the power battery, and the excess heat needs to be transferred to the PTC, and the water temperature of the water circuit in the PTC is heated to an allowable range, thereby achieving the purpose of consuming the engine heat.

[0060] In this embodiment, if the current maximum allowable recovery energy of the power battery is still less than or equal to the current energy obtained by the generator converting all the current heat energy of the engine into electrical energy after the engine transfers part of the heat energy to the PTC for heat dissipation, the working range of the generator is adjusted to the low-efficiency area. When the generator generates electricity in the low-efficiency area, the power generation efficiency is low, and more energy will be converted into heat and dissipated, thereby achieving the purpose of consuming the heat of the engine.

[0061] In this embodiment, after the working range of the generator is adjusted to the low-efficiency zone, if the current maximum allowable recovery energy of the power battery is still less than or equal to the current thermal energy of the engine converted into electrical energy by the generator, the engine is shut down.

[0062] In this embodiment, adjusting the working range of the generator to the low efficiency range includes:

[0063] The generator efficiency MAP table is obtained, and the speed and output power of the generator are adjusted based on the MAP table to be in a low efficiency zone.

[0064] In this embodiment, reducing the engine torque to a target torque value includes:

[0065] Obtaining a correspondence between an engine operating mode, an engine torque value and a torque filter coefficient, and establishing a filter table based on the correspondence;

[0066] The current engine operating mode is obtained, a torque filter coefficient is set based on the current operating mode, and the engine is filtered and controlled based on the torque filter coefficient to reduce the engine torque to a target torque value.

[0067] In this embodiment, the corresponding relationship between the engine operating condition, the engine torque value and the filter coefficient is obtained, including:

[0068] Get the current working mode of the engine;

[0069] Determining a first filter coefficient based on a current operating mode of the engine;

[0070] Get the current working mode of the motor;

[0071] Determining a second filter coefficient based on the current operating mode of the motor;

[0072] If the first filter coefficient is less than the second filter coefficient, setting the first filter coefficient to the torque filter coefficient;

[0073] If the first filter coefficient is greater than the second filter coefficient, the second filter coefficient is set as the torque filter coefficient.

[0074] Since the torque response accuracy of the engine is lower than that of the motor, this method is used to obtain a more accurate vehicle torque filter coefficient, which meets the torque filtering requirements of hybrid vehicles under different working conditions.

[0075] In this embodiment, the engine operating mode includes a working mode and a zero torque mode.

[0076] On the other hand, the present invention further provides a hybrid vehicle pressure relief control system, which is used to implement a hybrid vehicle pressure relief control strategy in the above technical solution, and the system includes:

[0077] A monitoring module, used to monitor the actual pressure value in the intake manifold and the torque value of the engine;

[0078] A calculation module, used to calculate a first difference between the safety pressure value and the actual pressure value, and a second difference between the current maximum allowable recovery energy of the power battery and the electric energy obtained by the generator converting all the current heat energy of the engine;

[0079] A torque adjustment module, used for adjusting the torque value of the engine;

[0080] The generator adjustment module is used to adjust the working range of the generator.

[0081] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The above-mentioned program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0082] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0083] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

[0084] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A hybrid vehicle pressure relief control method, characterized in that: include: Acquiring a pressure value in the intake manifold when surging occurs based on engine parameters, and setting the pressure value as a safety pressure value of the intake manifold; The automobile controller monitors the actual pressure value of the intake manifold in real time, and when the actual pressure value of the intake manifold is greater than the safety pressure value, it is determined that the engine is in a surging state; The vehicle controller reduces the engine torque to a target torque value based on filter control to reduce engine surge; The vehicle controller reduces the engine torque by: Acquire a first difference between the engine torque value and the target torque value; increasing the torque of the electric motor based on the first difference; Reducing the engine torque to the target torque value, and using vehicle components to consume heat energy generated by engine combustion; using vehicle components to consume heat energy generated by engine combustion includes: The vehicle controller obtains the current maximum allowable recovery energy of the power battery and the current heat energy of the engine converted by the generator into electrical energy, and calculates the second difference between the two; If the second difference is greater than zero, the engine transfers all heat energy to the generator to generate electricity; If the second difference is not greater than zero, the engine transfers a portion of the heat energy to the PTC for heat dissipation, and transfers another portion of the heat energy to the generator for power generation.

2. A hybrid vehicle pressure relief control method according to claim 1, characterized in that: If, after the engine transfers part of its heat energy to the PTC for heat dissipation, the current maximum allowable recovery energy of the power battery is still less than or equal to the generator converting all of the current heat energy of the engine into electrical energy, the working range of the generator will be adjusted to the low-efficiency zone.

3. A hybrid vehicle pressure relief control method according to claim 2, characterized in that: If the working range of the generator is adjusted to the low-efficiency zone, and if the current maximum allowable recovery energy of the power battery is still less than or equal to the current thermal energy of the engine converted into electrical energy by the generator, the engine will be shut down.

4. A hybrid vehicle pressure relief control method according to claim 2, characterized in that: Adjust the generator's operating range to the low-efficiency area, including: A generator efficiency MAP table is obtained, and the rotation speed and output power of the generator are adjusted based on the MAP table to be in a low efficiency zone.

5. The hybrid vehicle pressure relief control method according to claim 1, characterized in that: Reducing the engine torque to the target torque value further includes: Obtaining a correspondence between an engine operating mode, an engine torque value and a torque filter coefficient, and establishing a filter table based on the correspondence; The current engine operating mode is obtained, the torque filter coefficient is set based on the current operating mode, and the engine is filtered and controlled based on the torque filter coefficient to reduce the engine torque to the target torque value.

6. A hybrid vehicle pressure relief control method according to claim 5, characterized in that: Obtain the corresponding relationship between engine operating conditions, engine torque value and filter coefficient, including: Get the current working mode of the engine; Determining a first filter coefficient based on a current operating mode of the engine; Get the current working mode of the motor; Determining a second filter coefficient based on the current operating mode of the motor; If the first filter coefficient is less than the second filter coefficient, setting the first filter coefficient to the torque filter coefficient; If the first filter coefficient is greater than the second filter coefficient, the second filter coefficient is set as the torque filter coefficient.

7. A hybrid vehicle pressure relief control method according to claim 6, characterized in that: The engine operating mode includes a working mode and a zero torque mode.

8. A hybrid vehicle pressure relief control system, the system is used to implement a hybrid vehicle pressure relief control method as described in any one of claims 1 to 7, characterized in that: include A monitoring module, used to monitor the actual pressure value in the intake manifold and the torque value of the engine; A calculation module, used to calculate a first difference between the safety pressure value and the actual pressure value, and a second difference between the current maximum allowable recovery energy of the power battery and the electric energy obtained by the generator converting all the current heat energy of the engine; A torque adjustment module, used for adjusting the torque value of the engine; The generator adjustment module is used to adjust the working range of the generator.

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