Engine air inlet control system, control method and hybrid power vehicle
By setting up a vehicle controller, engine control unit and intake control unit in a hybrid vehicle, the engine intake amount is accurately controlled, and the problem of difficulty in engine intake control in the prior art is solved, and efficient engine intake control is achieved.
Patent Information
- Application Number
- CN202510128313.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-05
- Publication Date
- 2025-05-06
AI Technical Summary
The prior art is difficult to accurately control the engine intake volume when using turbocharger, Miller/Atkinson cycle and EGR valves, which increases the difficulty of engine intake control.
By setting up a vehicle controller, an engine control unit and an intake control unit in a hybrid vehicle, the engine compensation power is determined based on the vehicle driving parameters and the motor output power, and the opening and closing ratio of the intake valve is adjusted through the intake control unit to achieve accurate control of the engine intake amount.
The accuracy of engine intake control is achieved, the difficulty of engine intake control is reduced, and the combustion efficiency and power output are improved.
Smart Images
Figure CN119933875A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present application relate to the field of electronic control technology, and in particular to an engine air intake control system, a control method, and a hybrid vehicle. Background Art
[0002] Engine intake refers to the process of sucking air (or a mixture of air and fuel) into the cylinder during engine operation. This is the first stroke of a four-stroke engine (intake, compression, power, exhaust) and is the basis for the normal operation of the engine.
[0003] In the related technology, turbocharging, Miller / Atkinson cycle and EGR (Exhaust Gas Recirculation) valve are used in combination, and different control parameter combinations are set to achieve engine intake control. However, different control parameter combinations are likely to bring the same intake volume, thereby increasing the difficulty of engine intake control. Summary of the invention
[0004] The present application example provides an engine intake control system, a control method and a hybrid vehicle, and the technical solution is as follows.
[0005] On the one hand, an embodiment of the present application provides an engine intake control system applied to a hybrid vehicle, the system comprising a vehicle controller, an engine control unit, and an intake control unit;
[0006] The vehicle controller is used to determine the engine compensation power based on the vehicle driving parameters and the motor output power, and send the engine compensation power to the engine control unit, wherein the engine compensation power refers to the power required to be provided by the engine during the driving of the hybrid vehicle;
[0007] The engine control unit is used to determine the engine intake demand based on the engine compensation power, and send the engine intake demand to the intake control unit;
[0008] The intake control unit is used to adjust the opening and closing ratio of the intake valve based on the intake demand of the engine, and the opening and closing ratio of the intake valve is positively correlated with the intake demand of the engine.
[0009] Optionally, the system further includes a battery management unit; the vehicle controller is used to:
[0010] Determine the vehicle required power based on the collected vehicle driving parameters, where the vehicle required power refers to the power required for the hybrid vehicle to maintain the current driving state;
[0011] Sending the vehicle driving parameters and the vehicle required power to the battery management unit, and receiving the motor output power sent by the battery management unit;
[0012] Based on the vehicle demand power and the motor output power, the engine compensation power is obtained by difference calculation.
[0013] Optionally, the vehicle controller is used to:
[0014] Obtaining a pedal displacement and a real-time driving speed of the hybrid vehicle;
[0015] Determining a real-time required torque based on the pedal displacement and the maximum torque of the hybrid vehicle, wherein the maximum torque refers to the torque output by the engine and the motor under full load conditions;
[0016] The vehicle required power is determined based on the real-time required torque and the real-time driving speed.
[0017] Optionally, the battery management unit is used to:
[0018] determining the current state of charge of the electric motor battery and the battery temperature;
[0019] Determining the maximum discharge power of the electric motor battery based on the current state of charge and the battery temperature;
[0020] The motor output power is determined based on the maximum discharge power of the motor battery and the pedal displacement, and the motor output power is positively correlated with the pedal displacement.
[0021] Optional,
[0022] The vehicle controller is used to determine the working mode of the hybrid vehicle based on the vehicle working condition, and the working mode refers to the cooperative working mode between the engine and the electric motor in the hybrid vehicle;
[0023] The battery management unit is used to determine the target discharge power of the motor battery based on the working mode and the vehicle required power, and different working modes correspond to different target discharge powers;
[0024] The battery management unit is used to determine the motor output power based on the maximum discharge power, the target discharge power and the pedal displacement.
[0025] Optionally, the engine control unit is used to:
[0026] Determining an engine speed based on the engine compensation power and the engine real-time torque;
[0027] Determining the engine volumetric efficiency and the engine exhaust volume, wherein the engine volumetric efficiency is used to characterize the ratio between the actual engine intake volume and the maximum engine intake volume;
[0028] The engine intake air demand is determined based on the engine speed, the engine volumetric efficiency, and the engine exhaust volume.
[0029] Optionally, the hybrid vehicle comprises at least one engine cylinder, the at least one engine cylinder is connected to a central intake duct via an intake manifold, and the intake valve is used to control the intake amount of the central intake duct;
[0030] The air intake control unit is used to:
[0031] Acquiring gas parameters in the central air intake duct, wherein the gas parameters include at least one of gas flow rate, gas pressure and gas temperature;
[0032] The opening and closing ratio of the intake valve is determined based on the gas parameters in the central intake pipe and the engine intake demand.
[0033] Optionally, the hybrid vehicle comprises at least one engine cylinder, the engine cylinder corresponds to the intake valve one by one, and the intake valve is used to control the intake amount of the engine cylinder;
[0034] The air intake control unit is used to:
[0035] Acquiring gas parameters in each engine cylinder, wherein the gas parameters include at least one of gas flow rate, gas pressure and gas temperature;
[0036] Determining the cylinder air intake demand corresponding to the engine cylinder according to the cylinder parameters of each engine cylinder and the engine air intake demand, wherein the cylinder parameters include at least one of cylinder volume, intake duct parameters and valve size;
[0037] The opening and closing ratio of the intake valve is determined based on the gas parameters in the engine cylinder and the cylinder intake demand.
[0038] On the other hand, an embodiment of the present application provides a control method, the method is used for an engine intake control system of a hybrid vehicle, the system includes a vehicle controller, an engine control unit and an intake control unit;
[0039] The method comprises:
[0040] Determine the engine compensation power based on the vehicle driving parameters and the motor output power through the vehicle controller, and send the engine compensation power to the engine control unit, wherein the engine compensation power refers to the power required to be provided by the engine during the driving of the hybrid vehicle;
[0041] Determining an engine air intake demand based on the engine compensation power by the engine control unit, and sending the engine air intake demand to the air intake control unit;
[0042] The intake control unit adjusts the opening and closing ratio of the intake valve based on the intake demand of the engine, and the opening and closing ratio of the intake valve is positively correlated with the intake demand of the engine.
[0043] On the other hand, an embodiment of the present application provides a hybrid vehicle, which is provided with an engine intake control system as described in the above aspect.
[0044] In an embodiment of the present application, an intake control unit is provided in the engine intake control system, and the engine compensation power is determined by the vehicle controller based on the vehicle driving parameters and the motor output power, and the engine compensation power is sent to the engine control unit, so that the engine control unit determines the engine intake demand based on the engine compensation power, and sends the engine intake demand to the intake control unit. That is, the intake control unit can adjust the opening and closing ratio of the intake valve based on the engine intake demand to achieve engine intake control, thereby ensuring the accuracy of the engine intake control while reducing the difficulty of the engine intake control. BRIEF DESCRIPTION OF THE DRAWINGS
[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0046] Figure 1 A structural block diagram of an engine intake control system applied to a hybrid vehicle provided by an exemplary embodiment of the present application is shown;
[0047] Figure 2 A structural block diagram of an engine intake control system applied to a hybrid vehicle provided by another exemplary embodiment of the present application is shown;
[0048] Figure 3 A schematic diagram showing selection of the maximum discharge power of a motor battery provided by an exemplary embodiment of the present application is shown;
[0049] Figure 4 A flow chart of a control method provided by an exemplary embodiment of the present application is shown. DETAILED DESCRIPTION
[0050] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.
[0051] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.
[0052] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.
[0053] It should be understood that, although the terms first, second, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first parameter may also be referred to as the second parameter, and similarly, the second parameter may also be referred to as the first parameter. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".
[0054] First, the nouns involved in the embodiments of the present application are briefly introduced:
[0055] Hybrid Electric Vehicle (HEV) is a vehicle that uses two or more different power sources (such as an engine and an electric motor) at the same time, which can drive the vehicle simultaneously or individually. By combining the high energy density of the engine and the high efficiency of the electric motor, hybrid vehicles can improve fuel economy and reduce exhaust emissions while maintaining a range and driving performance similar to traditional fuel vehicles.
[0056] Engine intake control: refers to the regulation and management of parameters such as air flow, velocity, pressure and temperature entering the engine cylinder. By controlling the intake system, it can ensure that the engine can obtain the best intake volume and intake conditions under different working conditions (such as idling, acceleration, high-speed driving, etc.), thereby improving combustion efficiency, power output and fuel economy.
[0057] Vehicle Control Unit (VCU): Responsible for coordinating and managing the operation status of the vehicle. The VCU collects the driver's operating intentions (such as signals from the accelerator pedal, brake pedal, gear information, etc.) and combines the vehicle status (such as vehicle speed, battery power, etc.) to control the output power of the engine and motor to achieve acceleration, deceleration and braking of the vehicle.
[0058] Engine Control Unit: Also known as the Electronic Control Unit (ECU), it is the core component of the vehicle's electronic control system and is used to manage and control various electronic systems in the vehicle.
[0059] Battery Management System (BMS): An electronic system used to monitor and manage the operating status of rechargeable batteries (including single cells or battery packs). It monitors battery voltage, current, temperature, SOC (State of Charge) and SOH (State of Health) and other parameters to achieve control, safety protection, balance management and data communication of the battery charging and discharging process.
[0060] Please refer to Figure 1 , which shows a structural block diagram of an engine intake control system applied to a hybrid vehicle provided by an exemplary embodiment of the present application.
[0061] Optionally, the engine intake control system 100 may include a vehicle controller 110 , an engine control unit 120 and an intake control unit 130 .
[0062] The vehicle controller 110 is used to determine the engine compensation power based on the vehicle driving parameters and the motor output power, and send the engine compensation power to the engine control unit. The engine compensation power refers to the power that needs to be provided by the engine during the driving of the hybrid vehicle.
[0063] Optionally, a hybrid vehicle can use an electric motor and an engine as power sources, so that during the vehicle's travel, the electric motor and the engine jointly provide output power to the vehicle to drive the vehicle. The electric motor can achieve power output by discharging the battery, while the engine needs to achieve power output by burning fuel in the engine cylinder.
[0064] Optionally, during the fuel combustion process, sufficient air needs to be mixed with it. That is, the amount of air intake in the engine cylinder is the basis of the engine power output, and the engine power output is affected by the engine intake. Optionally, the more air intake in the engine cylinder, the more air can participate in the combustion, and the amount of fuel injection can also be increased accordingly, thereby generating greater combustion energy and improving the engine's power output.
[0065] In some embodiments, during the driving process of the vehicle, the electric motor and the engine jointly provide driving power for it. Therefore, in order to control the engine intake volume according to the power demand, the vehicle controller can first determine the engine compensation power according to the vehicle driving parameters and the motor output power. The engine compensation power refers to the power that needs to be provided by the engine during the driving of the hybrid vehicle.
[0066] Optionally, the vehicle driving parameters may include vehicle state parameters of the hybrid vehicle during driving, such as driving speed, battery power, etc., and may also include operational intentions imposed by the driver received by the hybrid vehicle during driving, such as signals such as the accelerator pedal, brake pedal, gear information, etc., and may also include other possible parameters, which are not limited to the embodiments of the present application.
[0067] Optionally, the motor output power refers to the mechanical power output by the motor per unit time, that is, the power actually used by the motor to drive the load. Optionally, the motor output power is determined by the electrical power input to the motor, that is, the motor output power is related to the battery discharge power.
[0068] In one possible implementation, the vehicle controller may first determine the total power required for the hybrid vehicle during driving based on the vehicle driving parameters, then determine the engine compensation power based on the total power and the motor output power, and send the engine compensation power to the engine control unit so that the engine control unit can determine the engine intake demand based on the engine compensation power.
[0069] Optionally, data transmission between the vehicle controller and the engine control unit may be achieved via a CAN (Controller Area Network) bus, a vehicle network, or other communication technologies, which is not limited in the embodiments of the present application.
[0070] The engine control unit 120 is used to determine the engine intake air demand based on the engine compensation power, and send the engine intake air demand to the intake control unit.
[0071] In some embodiments, after receiving the engine compensation power sent by the vehicle controller, the engine control unit can further determine the engine air intake demand based on the engine compensation power, and then send the engine air intake demand to the air intake control unit, so that the air intake control unit can perform intake control based on the engine air intake demand.
[0072] Optionally, the engine intake demand is the amount of air required for the engine to achieve fuel combustion and power output, that is, the mass or volume of air entering the engine cylinder per unit time, usually expressed in liters per minute (L / min) or cubic meters per hour (m 3 / h).
[0073] Optionally, the engine air intake demand is positively correlated with the engine compensation power. The higher the required engine compensation power, the greater the engine air intake demand. Conversely, the lower the required engine compensation power, the smaller the engine air intake demand.
[0074] Optionally, data transmission between the engine control unit and the intake control unit may be achieved through a CAN bus, through a vehicle network, or through other communication technologies, which is not limited in the embodiments of the present application.
[0075] The intake control unit 130 is used to adjust the opening and closing ratio of the intake valve based on the intake demand of the engine. The opening and closing ratio of the intake valve is positively correlated with the intake demand of the engine.
[0076] In some embodiments, after receiving the engine air intake demand transmitted by the engine control unit, the air intake control unit can adjust the opening and closing ratio of the intake valve according to the engine air intake demand, thereby achieving air intake control of the engine.
[0077] Optionally, the intake valve is used to control the gas flow entering the engine cylinder, and the gas flow entering the engine cylinder is different under different opening and closing ratios. Optionally, the opening and closing ratio of the intake valve is positively correlated with the engine intake demand. The greater the engine intake demand, the greater the opening and closing ratio of the intake valve. Conversely, the smaller the engine intake demand, the smaller the opening and closing ratio of the intake valve.
[0078] Optionally, in order to facilitate the air intake control unit to control the opening and closing ratio of the air intake valve, the air intake valve may be an electrically controlled air intake valve, that is, the air intake control unit controls the opening and closing ratio of the air intake valve by sending an electronic signal to the air intake valve.
[0079] To summarize, in the embodiment of the present application, an intake control unit is provided in the engine intake control system, and the engine compensation power is determined by the vehicle controller based on the vehicle driving parameters and the motor output power, and the engine compensation power is sent to the engine control unit, so that the engine control unit determines the engine intake demand based on the engine compensation power, and sends the engine intake demand to the intake control unit. That is, the intake control unit can adjust the opening and closing ratio of the intake valve based on the engine intake demand to achieve engine intake control, thereby ensuring the accuracy of the engine intake control while reducing the difficulty of the engine intake control.
[0080] Optionally, in order to ensure the accuracy of the engine intake control, the vehicle controller needs to accurately determine the engine compensation power, the engine control unit needs to accurately determine the engine intake demand, and the intake control unit needs to accurately determine the opening and closing ratio of the intake valve. The following will describe in detail the determination process of the three through specific embodiments.
[0081] Please refer to Figure 2 , which shows a structural block diagram of an engine intake control system applied to a hybrid vehicle provided by another exemplary embodiment of the present application.
[0082] Indicatively, Figure 2 As shown, the engine intake control system 200 includes not only a vehicle controller 210, an engine control unit 220 and an intake control unit 230, but also a battery management unit 240. There is data communication between the battery management unit 240 and the vehicle controller 210.
[0083] The vehicle controller 210 is used to determine the vehicle demand power based on the collected vehicle driving parameters. The vehicle demand power refers to the power required for the hybrid vehicle to maintain the current driving state.
[0084] Optionally, before determining the engine compensation power, the vehicle controller first needs to determine the power required for the hybrid vehicle to maintain the current driving state, that is, the vehicle demand power.
[0085] In some embodiments, the vehicle controller may collect vehicle driving parameters, thereby determining the vehicle required power according to the vehicle driving parameters. The vehicle driving parameters may include vehicle state parameters of the hybrid vehicle during driving, such as driving speed, battery power, etc., and may also include operation intentions imposed by the driver received by the hybrid vehicle during driving, such as accelerator pedal, brake pedal, gear position information, etc.
[0086] In one possible implementation, the vehicle controller can obtain the pedal displacement and the real-time driving speed of the hybrid vehicle, and thus first determine the real-time required torque based on the pedal displacement and the maximum torque of the hybrid vehicle, and then determine the vehicle required power based on the real-time required torque and the real-time driving speed.
[0087] Optionally, the pedal displacement refers to the pedal displacement of the accelerator pedal. The vehicle controller can determine the pedal displacement by receiving the displacement signal sent by the pedal displacement sensor. Optionally, the pedal displacement can be expressed in the form of a pedal opening percentage (0 to 100%). In a possible implementation, the vehicle controller can collect two accelerator pedal voltage signals and convert them into pedal opening percentage after filtering.
[0088] Optionally, the vehicle controller can directly obtain the real-time speed information of the hybrid vehicle through the vehicle speed sensor, and can also receive real-time speed information sent by other control units (such as the power control unit MCU) through the CAN bus.
[0089] Among them, the maximum torque of a hybrid vehicle refers to the torque jointly output by the engine and the electric motor of the hybrid vehicle under full load conditions, and the real-time required torque is equal to the maximum torque multiplied by the pedal displacement.
[0090] Optionally, the vehicle demand power is equal to (real-time demand torque × real-time driving speed) / conversion factor.
[0091] The vehicle controller 210 is used to send the vehicle driving parameters and the vehicle required power to the battery management unit, and receive the motor output power sent by the battery management unit.
[0092] In some embodiments, after calculating the vehicle's required power, the vehicle controller can transmit the vehicle's required power and vehicle driving parameters to the battery management unit through the communication bus, so that the battery management unit controls the battery discharge according to the received data, thereby controlling the motor to generate output power. Furthermore, the battery management unit returns the motor output power to the vehicle controller through the communication bus, so that the vehicle controller can determine the engine compensation power.
[0093] In one possible implementation, after receiving the vehicle driving parameters, the battery management unit may first determine the current charge state and battery temperature of the motor battery, and then determine the maximum discharge power of the motor battery based on the current charge state and battery temperature by looking up a table, and then determine the motor output power based on the maximum discharge power of the motor battery and the pedal displacement.
[0094] Optionally, the state of charge (SOC) of the motor battery refers to the ratio of the current remaining power of the battery to the nominal capacity of the battery, usually expressed as a percentage. For example, SOC = 100% means that the battery is fully charged, and SOC = 0% means that the battery is completely discharged. Optionally, the battery management unit can monitor the state of charge of the motor battery in real time.
[0095] Optionally, under the same charge state, the maximum discharge power of the motor battery increases first and then decreases as the temperature increases. Taking a certain model of motor battery as an example, schematically, Figure 3 As shown, when the state of charge is 40% and the battery temperature is between 25°C and 40°C, the maximum discharge power reaches a peak value of 85Kw (kilowatts).
[0096] Optionally, the motor output power is equal to the maximum discharge power × pedal displacement, that is, when the maximum discharge power is determined, the motor output power is positively correlated with the pedal displacement. When the pedal displacement is 100%, the motor battery outputs full power. For example, when the state of charge is 40% and the battery temperature is 40%, 100% pedal displacement corresponds to 85Kw motor output power.
[0097] It should be noted that the embodiments of the present application are only described by taking the case that there is no energy loss in the process of converting electrical energy into kinetic energy as an example, that is, the embodiments of the present application assume that the battery discharge power is fully converted into the motor output power. In actual application, considering the energy conversion loss, the battery management unit can also determine the motor output power based on the loss coefficient, the maximum discharge power and the pedal displacement, that is, the motor output power = loss coefficient × maximum discharge power × pedal displacement.
[0098] Optionally, considering that in the process where the engine and the electric motor jointly provide output power to drive the hybrid vehicle, there are multiple possible operating modes, such as pure electric mode, series mode, parallel mode, engine direct drive mode, etc., the output power provided by the engine and the electric motor in different operating modes is also different. Therefore, in order to optimize the operation process of the hybrid vehicle, the battery management unit can also determine the output power of the motor in combination with the current operating mode of the hybrid vehicle.
[0099] In one possible implementation, the vehicle controller can determine the working mode of the hybrid vehicle according to the vehicle operating conditions, and the working mode refers to the collaborative working mode between the engine and the electric motor in the hybrid vehicle. Optionally, the vehicle operating conditions may include battery power, driving requirements, engine efficiency, driving mode selection, etc. For example, when the battery power is sufficient, the pure electric mode can be used; when the battery power is below a certain threshold, the series mode or the parallel mode can be used. For example, at low speed or when parking, the pure electric mode can be used; at high speed or when acceleration requirements are large, the parallel mode or the engine direct drive mode can be used.
[0100] Furthermore, after determining the operating mode of the hybrid vehicle, the vehicle controller can notify the battery management unit of the current operating mode of the hybrid vehicle through the communication bus, so that the battery management unit can determine the target discharge power of the motor battery based on the operating mode and the vehicle's required power, and determine the motor output power based on the maximum discharge power, target discharge power and pedal displacement.
[0101] Among them, different working modes correspond to different target discharge powers. Optionally, the corresponding motor power demand output ratio and engine power demand output ratio can be set for different working modes. For example, in pure electric mode, the motor power demand output ratio is 100%; in parallel mode, the motor power demand output ratio can be 30%, and the engine power demand output ratio can be 70%; in series mode, the motor power demand output ratio can be 20%, and the engine power demand output ratio can be 80%. Therefore, the target discharge power of the motor battery can be equal to the motor power demand output ratio × the vehicle demand power, that is, in the current working mode, only the motor needs to provide the target discharge power.
[0102] Optionally, the maximum discharge power multiplied by the pedal displacement can obtain the real-time battery discharge power of the motor battery. Without considering the working mode, the real-time battery discharge power can be used as the motor output power; when considering the working mode, the battery management unit can compare the real-time battery discharge power with the target discharge power. When the target discharge power is greater than the real-time battery discharge power, the battery management unit can control the motor battery to discharge at the real-time battery discharge power, that is, the motor output power = real-time battery discharge power = maximum discharge power × pedal displacement; when the target discharge power is not greater than the real-time battery discharge power, the battery management unit can control the motor battery to discharge at the target discharge power, that is, the motor output power = target discharge power = motor power demand output ratio × vehicle demand power.
[0103] The vehicle controller 210 is used to obtain the engine compensation power through difference calculation based on the vehicle demand power and the motor output power.
[0104] In some embodiments, after receiving the motor output power returned by the battery management unit, the vehicle controller can determine the engine compensation power by difference calculation based on the vehicle demand power and the motor output power, that is, engine compensation power = vehicle demand power - motor output power.
[0105] The engine control unit 220 is used to determine the engine speed based on the engine compensation power and the engine real-time torque.
[0106] In some implementations, after receiving the engine compensation power sent by the vehicle controller, the engine control unit may first determine the engine speed according to the engine compensation power and the engine real-time torque.
[0107] Among them, the engine real-time torque refers to the rotational torque output from the crankshaft end of the engine, usually in "Newton meters" (Nm). The engine speed refers to the number of rotations of the engine crankshaft per minute, usually expressed in "revolutions per minute" (RPM). Optionally, engine speed = (engine compensation power × conversion factor) ÷ engine real-time torque.
[0108] The engine control unit 220 is used to determine the engine volumetric efficiency and the engine exhaust volume. The engine volumetric efficiency is used to characterize the ratio between the actual engine intake volume and the maximum engine intake volume.
[0109] Optionally, during the fuel combustion process, in addition to intake, exhaust is also required in the engine cylinder to control the cylinder pressure, that is, the engine intake demand is also related to the engine exhaust volume. In some embodiments, in order to determine the engine intake demand at the current moment, the engine control unit needs to first determine the engine volumetric efficiency and the engine exhaust volume.
[0110] Optionally, the engine volumetric efficiency is used to characterize the ratio between the actual intake volume of the engine and the maximum intake volume, wherein the maximum intake volume refers to the maximum amount of air that can be inhaled by the engine cylinder under ideal conditions.
[0111] Optionally, the engine exhaust volume can be calculated by measuring the engine cylinder diameter, piston stroke and number of cylinders, or it can be indirectly estimated by measuring the pressure change in the cylinder with a cylinder pressure gauge, which is not limited to the embodiments of the present application.
[0112] The engine control unit 220 is used to determine the engine intake air demand based on the engine speed, the engine volumetric efficiency and the engine exhaust volume.
[0113] In some embodiments, after obtaining the engine speed, engine volumetric efficiency and engine exhaust volume, the engine control unit can determine the engine intake demand and transmit it to the intake control unit. Optionally, engine intake volume = speed × engine exhaust volume × engine volumetric efficiency × conversion system.
[0114] The air intake control unit 230 is used to obtain gas parameters in the central air intake duct, where the gas parameters include at least one of gas flow rate, gas pressure and gas temperature.
[0115] Optionally, in order to simplify the control of the engine intake, the intake valve can be directly arranged in the central intake duct, so that the intake control unit only needs to control a single intake valve. In a possible implementation, the hybrid vehicle includes at least one engine cylinder, and at least one engine cylinder is connected to the central intake duct through an intake manifold, so that the intake valve is arranged in the central intake duct, and the intake valve is directly used to control the intake amount of the central intake duct.
[0116] In the above-mentioned intake valve installation mode, the intake control unit only needs to obtain the gas parameters in the central intake pipe. Optionally, the gas parameters include at least one of gas flow rate, gas pressure and gas temperature.
[0117] Optionally, the gas flow rate can be directly measured by an anemometer, or it can be indirectly calculated and determined by measuring the vortex frequency or amplitude, or it can be obtained by other means, which is not limited in the embodiments of the present application. Optionally, the gas pressure can be directly measured by a cylinder pressure gauge, or it can be indirectly calculated by measuring related parameters, or it can be obtained by other means, which is not limited in the embodiments of the present application. Optionally, the gas temperature can be directly measured using a high-temperature sensor, or it can be indirectly estimated and determined by measuring the exhaust temperature, or it can be obtained by other means, which is not limited in the embodiments of the present application.
[0118] Optionally, the gas parameters in the central intake duct may be directly determined based on the gas in the central intake duct, or the average of the gas parameters in each engine cylinder may be taken.
[0119] The intake control unit 230 is used to determine the opening and closing ratio of the intake valve based on the gas parameters in the central intake duct and the engine intake demand.
[0120] Furthermore, after obtaining the gas parameters in the central intake duct, the intake control unit can determine the opening and closing ratio of the intake valve based on the gas parameters in the central intake duct and the engine intake demand.
[0121] Optionally, the engine intake demand = gas flow rate × intake valve opening and closing area × (gas pressure × coefficient 1 + coefficient 2) × (gas absolute temperature + coefficient 3) / (gas absolute temperature + gas actual temperature), where the actual gas temperature refers to the temperature of the gas at the current-carrying cross-section, coefficient 1 can be taken as 10, coefficient 2 can be taken as 1, and coefficient 3 can be taken as 20.
[0122] Optionally, different opening and closing ratios of the intake valve correspond to different opening and closing areas of the intake valve, wherein the opening and closing area of the intake valve refers to the effective cross-sectional area through which the gas can pass when the intake valve is opened at a corresponding opening and closing ratio.
[0123] The intake control unit 230 is used to obtain gas parameters in each engine cylinder, where the gas parameters include at least one of gas flow rate, gas pressure and gas temperature.
[0124] Optionally, in order to improve the control accuracy of the air intake amount of each engine cylinder, an intake valve may be arranged in the intake duct of each engine cylinder, so that the intake control unit controls each intake valve separately. In a possible implementation, the hybrid vehicle includes at least one engine cylinder, the engine cylinder corresponds to the intake valve one by one, and an intake valve is arranged in the intake duct of each engine cylinder, so that the intake valve is used to control the air intake amount of the engine cylinder.
[0125] In the above-mentioned intake valve installation mode, the intake control unit needs to obtain the gas parameters in each engine cylinder. Optionally, the gas parameters include at least one of gas flow rate, gas pressure and gas temperature.
[0126] Optionally, the gas flow rate can be directly measured by an anemometer, or it can be indirectly calculated and determined by measuring the vortex frequency or amplitude, or it can be obtained by other means, which is not limited in the embodiments of the present application. Optionally, the gas pressure can be directly measured by a cylinder pressure gauge, or it can be indirectly calculated by measuring related parameters, or it can be obtained by other means, which is not limited in the embodiments of the present application. Optionally, the gas temperature can be directly measured using a high-temperature sensor, or it can be indirectly estimated and determined by measuring the exhaust temperature, or it can be obtained by other means, which is not limited in the embodiments of the present application.
[0127] The intake control unit 230 is used to determine the cylinder intake demand corresponding to the engine cylinder according to the cylinder parameters of each engine cylinder and the engine intake demand, and the cylinder parameters include at least one of the cylinder volume, the intake pipe parameters and the valve size.
[0128] Furthermore, considering that different engine cylinders may have different intake demands, in order to control the intake valves corresponding to each engine cylinder, the intake control unit needs to determine the cylinder intake demand corresponding to the engine cylinder based on the cylinder parameters of each engine cylinder and the engine intake demand.
[0129] Optionally, the engine air intake demand is equal to the sum of the cylinder air intake demands corresponding to all engine cylinders. Different engine cylinders may correspond to the same cylinder air intake demand or to different cylinder air intake demands.
[0130] Optionally, the cylinder parameter includes at least one of a cylinder volume, an intake pipe parameter, and a valve size. For example, when the intake pipe parameter and the valve size are consistent, the intake control unit may allocate the intake demand proportion corresponding to each engine cylinder according to the cylinder volume; for another example, when the cylinder volume and the intake pipe parameter are consistent, the intake control unit may allocate the intake demand proportion corresponding to each engine cylinder according to the valve size.
[0131] The intake control unit 230 is used to determine the opening and closing ratio of the intake valve based on the gas parameters in the engine cylinder and the cylinder intake demand.
[0132] Furthermore, after determining the cylinder intake demand corresponding to each engine cylinder, the intake control unit can determine the opening and closing ratio of the intake valve according to the gas parameters in each engine cylinder and the cylinder intake demand.
[0133] Optionally, the engine intake demand = gas flow rate × intake valve opening and closing area × (gas pressure × coefficient 1 + coefficient 2) × (gas absolute temperature + coefficient 3) / (gas absolute temperature + gas actual temperature), where the actual gas temperature refers to the temperature of the gas at the current-carrying cross-section, coefficient 1 can be taken as 10, coefficient 2 can be taken as 1, and coefficient 3 can be taken as 20.
[0134] Optionally, different opening and closing ratios of the intake valve correspond to different opening and closing areas of the intake valve, wherein the opening and closing area of the intake valve refers to the effective cross-sectional area through which the gas can pass when the intake valve is opened at a corresponding opening and closing ratio.
[0135] In the above embodiment, the engine compensation power is determined by combining the vehicle driving parameters and the motor output power, thereby converting the engine compensation power into the engine speed, and determining the engine intake demand based on the engine speed, engine volumetric efficiency and engine exhaust volume. This can improve the accuracy of determining the engine intake demand and thereby improve the accuracy of engine intake control.
[0136] In addition, in the process of determining the output power of the electric motor, the current charge state of the engine battery, the battery temperature and the operating mode of the vehicle can be combined to reasonably control the power output ratio of the electric motor and the engine, thereby optimizing the power output control without affecting the driving process of the vehicle.
[0137] Please refer to Figure 4 , which shows a flow chart of a control method provided by an exemplary embodiment of the present application. The method is used for an engine intake control system of a hybrid vehicle, and the system includes a vehicle controller, an engine control unit, and an intake control unit. The method includes the following steps:
[0138] Step 401, the vehicle controller determines the engine compensation power based on the vehicle driving parameters and the motor output power, and sends the engine compensation power to the engine control unit. The engine compensation power refers to the power that needs to be provided by the engine during the driving of the hybrid vehicle.
[0139] Optionally, a hybrid vehicle can use an electric motor and an engine as power sources, so that during the vehicle's travel, the electric motor and the engine jointly provide output power to the vehicle to drive the vehicle. The electric motor can achieve power output by discharging the battery, while the engine needs to achieve power output by burning fuel in the engine cylinder.
[0140] Optionally, during the fuel combustion process, sufficient air needs to be mixed with it. That is, the amount of air intake in the engine cylinder is the basis of the engine power output, and the engine power output is affected by the engine intake. Optionally, the more air intake in the engine cylinder, the more air can participate in the combustion, and the amount of fuel injection can also be increased accordingly, thereby generating greater combustion energy and improving the engine's power output.
[0141] In some embodiments, during the driving process of the vehicle, the electric motor and the engine jointly provide driving power for it. Therefore, in order to control the engine intake volume according to the power demand, the vehicle controller can first determine the engine compensation power according to the vehicle driving parameters and the motor output power. The engine compensation power refers to the power that needs to be provided by the engine during the driving of the hybrid vehicle.
[0142] Optionally, the vehicle driving parameters may include vehicle state parameters of the hybrid vehicle during driving, such as driving speed, battery power, etc., and may also include operating intentions exerted by the driver received by the hybrid vehicle during driving (such as signals such as accelerator pedal, brake pedal, gear information, etc.), etc. The embodiments of the present application are not limited to this.
[0143] Optionally, the motor output power refers to the mechanical power output by the motor per unit time, that is, the power actually used by the motor to drive the load. Optionally, the motor output power is determined by the electrical power input to the motor, that is, the motor output power is related to the battery discharge power.
[0144] In one possible implementation, the vehicle controller may first determine the total power required for the hybrid vehicle during driving based on the vehicle driving parameters, then determine the engine compensation power based on the total power and the motor output power, and send the engine compensation power to the engine control unit so that the engine control unit can determine the engine intake demand based on the engine compensation power.
[0145] Optionally, data transmission between the vehicle controller and the engine control unit may be achieved via a CAN (Controller Area Network) bus, a vehicle network, or other communication technologies, which is not limited in the embodiments of the present application.
[0146] Step 402 : determining the engine air intake demand based on the engine compensation power through the engine control unit, and sending the engine air intake demand to the air intake control unit.
[0147] In some embodiments, after receiving the engine compensation power sent by the vehicle controller, the engine control unit can further determine the engine air intake demand based on the engine compensation power, and then send the engine air intake demand to the air intake control unit, so that the air intake control unit can perform intake control based on the engine air intake demand.
[0148] Optionally, the engine intake demand is the amount of air required for the engine to achieve fuel combustion and power output, that is, the mass or volume of air entering the engine cylinder per unit time, usually expressed in liters per minute (L / min) or cubic meters per hour (m 3 / h).
[0149] Optionally, the engine air intake demand is positively correlated with the engine compensation power. The higher the required engine compensation power, the greater the engine air intake demand. Conversely, the lower the required engine compensation power, the smaller the engine air intake demand.
[0150] Optionally, data transmission between the engine control unit and the intake control unit may be achieved through a CAN bus, through a vehicle network, or through other communication technologies, which is not limited in the embodiments of the present application.
[0151] Step 403, adjusting the opening and closing ratio of the intake valve based on the intake demand of the engine through the intake control unit, and the opening and closing ratio of the intake valve is positively correlated with the intake demand of the engine.
[0152] In some embodiments, after receiving the engine air intake demand transmitted by the engine control unit, the air intake control unit can adjust the opening and closing ratio of the intake valve according to the engine air intake demand, thereby achieving air intake control of the engine.
[0153] Optionally, the intake valve is used to control the gas flow entering the engine cylinder, and the gas flow entering the engine cylinder is different under different opening and closing ratios. Optionally, the opening and closing ratio of the intake valve is positively correlated with the engine intake demand. The greater the engine intake demand, the greater the opening and closing ratio of the intake valve. Conversely, the smaller the engine intake demand, the smaller the opening and closing ratio of the intake valve.
[0154] Optionally, in order to facilitate the air intake control unit to control the opening and closing ratio of the air intake valve, the air intake valve may be an electrically controlled air intake valve, that is, the air intake control unit controls the opening and closing ratio of the air intake valve by sending an electronic signal to the air intake valve.
[0155] To summarize, in the embodiment of the present application, an intake control unit is provided in the engine intake control system, and the engine compensation power is determined by the vehicle controller based on the vehicle driving parameters and the motor output power, and the engine compensation power is sent to the engine control unit, so that the engine control unit determines the engine intake demand based on the engine compensation power, and sends the engine intake demand to the intake control unit. That is, the intake control unit can adjust the opening and closing ratio of the intake valve based on the engine intake demand to achieve engine intake control, thereby ensuring the accuracy of the engine intake control while reducing the difficulty of the engine intake control.
[0156] The solutions shown in the above embodiments of the present application can be applied to hybrid vehicles, such as hybrid cars. Specifically, the present application also provides a hybrid vehicle, which includes the engine intake control system shown in the above embodiments.
[0157] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.
[0158] The above are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.
Claims
1. An engine intake control system for a hybrid vehicle, characterized in that: The system includes a vehicle controller, an engine control unit and an intake control unit; The vehicle controller is used to determine the engine compensation power based on the vehicle driving parameters and the motor output power, and send the engine compensation power to the engine control unit, wherein the engine compensation power refers to the power required to be provided by the engine during the driving of the hybrid vehicle; The engine control unit is used to determine the engine intake demand based on the engine compensation power, and send the engine intake demand to the intake control unit; The intake control unit is used to adjust the opening and closing ratio of the intake valve based on the intake demand of the engine, and the opening and closing ratio of the intake valve is positively correlated with the intake demand of the engine.
2. The system according to claim 1, characterized in that The system also includes a battery management unit; the vehicle controller is used to: Determine the vehicle required power based on the collected vehicle driving parameters, where the vehicle required power refers to the power required for the hybrid vehicle to maintain the current driving state; Sending the vehicle driving parameters and the vehicle required power to the battery management unit, and receiving the motor output power sent by the battery management unit; Based on the vehicle demand power and the motor output power, the engine compensation power is obtained by difference calculation.
3. The system according to claim 2, characterized in that The vehicle controller is used for: Obtaining a pedal displacement and a real-time driving speed of the hybrid vehicle; Determining a real-time required torque based on the pedal displacement and the maximum torque of the hybrid vehicle, wherein the maximum torque refers to the torque output by the engine and the motor under full load conditions; The vehicle required power is determined based on the real-time required torque and the real-time driving speed.
4. The system according to claim 2, characterized in that The battery management unit is used for: determining the current state of charge of the electric motor battery and the battery temperature; Determining the maximum discharge power of the electric motor battery based on the current state of charge and the battery temperature; The motor output power is determined based on the maximum discharge power of the motor battery and the pedal displacement, and the motor output power is positively correlated with the pedal displacement.
5. The system according to claim 4, characterized in that The vehicle controller is used to determine the working mode of the hybrid vehicle based on the vehicle working condition, and the working mode refers to the cooperative working mode between the engine and the electric motor in the hybrid vehicle; The battery management unit is used to determine the target discharge power of the motor battery based on the working mode and the vehicle required power, and different working modes correspond to different target discharge powers; The battery management unit is used to determine the motor output power based on the maximum discharge power, the target discharge power and the pedal displacement.
6. The system according to claim 1, characterized in that The engine control unit is used for: Determining an engine speed based on the engine compensation power and the engine real-time torque; Determining the engine volumetric efficiency and the engine exhaust volume, wherein the engine volumetric efficiency is used to characterize the ratio between the actual engine intake volume and the maximum engine intake volume; The engine intake air demand is determined based on the engine speed, the engine volumetric efficiency, and the engine exhaust volume.
7. The system according to claim 1, characterized in that The hybrid vehicle comprises at least one engine cylinder, the at least one engine cylinder is connected to a central intake duct via an intake manifold, and the intake valve is used to control the intake amount of the central intake duct; The air intake control unit is used to: Acquiring gas parameters in the central air intake duct, wherein the gas parameters include at least one of gas flow rate, gas pressure and gas temperature; The opening and closing ratio of the intake valve is determined based on the gas parameters in the central intake pipe and the engine intake demand.
8. The system according to claim 1, characterized in that The hybrid vehicle comprises at least one engine cylinder, the engine cylinder corresponds to the intake valve one by one, and the intake valve is used to control the intake amount of the engine cylinder; The air intake control unit is used to: Acquiring gas parameters in each engine cylinder, wherein the gas parameters include at least one of gas flow rate, gas pressure and gas temperature; Determining the cylinder intake demand corresponding to the engine cylinder according to the cylinder parameters of each engine cylinder and the engine intake demand, wherein the cylinder parameters include at least one of cylinder volume, intake pipe parameters and valve size; The opening and closing ratio of the intake valve is determined based on the gas parameters in the engine cylinder and the cylinder intake demand.
9. A control method, characterized in that: The method is used for an engine intake control system of a hybrid vehicle, the system comprising a vehicle controller, an engine control unit and an intake control unit; The method comprises: Determine the engine compensation power based on the vehicle driving parameters and the motor output power through the vehicle controller, and send the engine compensation power to the engine control unit, wherein the engine compensation power refers to the power required to be provided by the engine during the driving of the hybrid vehicle; Determining an engine air intake demand based on the engine compensation power by the engine control unit, and sending the engine air intake demand to the air intake control unit; The intake control unit adjusts the opening and closing ratio of the intake valve based on the intake demand of the engine, and the opening and closing ratio of the intake valve is positively correlated with the intake demand of the engine.
10. A hybrid vehicle, characterized in that: The vehicle is provided with an engine intake control system as claimed in any one of claims 1 to 8.