Engine control method and vehicle

Abstract

The invention provides an engine control method and a vehicle, and relates to the technical field of vehicle control. The method comprises the steps that when a vehicle enters an idling activation state, the initial torque of an engine is obtained according to rotating speed data and load data of the engine; according to the state of the power transmission system component of the vehicle and the load data, the load state of the engine is determined; and based on the load state and the rotating speed data and the load data of the engine, the initial torque is corrected, and the target torque is obtained to control the engine. The target torque is determined by adopting a differentiation mode based on different load states of the engine, so that the method is more adaptive to the working condition characteristics of the hybrid electric vehicle. When the target torque is obtained, the load size and the rotating speed of the engine are comprehensively considered, the initial torque is corrected, the target torque matched with the current load state can be obtained, and therefore when the engine is controlled through the target torque, the idling stability of the vehicle can be effectively improved.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to an engine control method and a vehicle. Background Technology

[0002] When a vehicle enters idling mode, engine idle speed control is necessary to stabilize the engine speed at the target speed and ensure vehicle idling stability. Therefore, engine idle speed control is of great significance for improving vehicle operating quality.

[0003] Idle speed control in related technologies is typically designed for traditional gasoline-powered vehicles. However, compared to traditional gasoline-powered vehicles, hybrid vehicles operate under more complex and diverse conditions. Traditional idle speed control strategies are difficult to adapt to the operating characteristics of hybrid vehicles, which can easily lead to poor vehicle idle stability, causing problems such as vehicle vibration, increased noise, and increased fuel consumption. Summary of the Invention

[0004] This application provides an engine control method and a vehicle to solve the technical problem that traditional idle speed control strategies in the related art are difficult to adapt to hybrid vehicles, which easily leads to poor vehicle idle speed stability.

[0005] In a first aspect, embodiments of this application provide an engine control method, including: When the vehicle enters the idle activation state, the initial torque of the engine is obtained based on the engine speed data and load data; The load status of the engine is determined based on the status of the powertrain components of the vehicle and the load data. Based on the load condition, as well as the engine speed and load data, the initial torque is corrected to obtain the target torque; The engine is controlled according to the target torque.

[0006] In this embodiment, when the vehicle enters the idle activation state, the initial torque of the engine is first obtained based on the engine speed and load data. Then, based on the state of the powertrain components in the vehicle and the aforementioned load data, the engine load state is determined. Furthermore, based on the load state, engine speed, and load data, the initial torque is corrected to obtain the target torque. Finally, the engine is controlled according to the target torque. Thus, firstly, the target torque is determined using a differentiated approach based on different engine load states to control the engine's idle speed, which is more suitable for the operating conditions of hybrid vehicles. Secondly, when obtaining the target torque, the engine load and speed are comprehensively considered, and the initial torque is corrected to obtain a target torque that matches the current load state. Therefore, when controlling the engine with the target torque, idle speed control that better fits the actual operating conditions of hybrid vehicles can be achieved, effectively improving vehicle idle stability and reducing issues such as vehicle vibration, increased noise, and increased fuel consumption.

[0007] In one possible implementation, the load state includes an unloaded state and a loaded state; The step of correcting the initial torque based on the load state, engine speed data, and load data to obtain the target torque includes: If the load state is an unloaded state, the initial torque is corrected based on the engine speed data and water temperature data to obtain the target torque; If the load state is a loaded state, the initial torque is corrected based on the engine speed data, load data, and water temperature data to obtain the target torque.

[0008] In this embodiment, by distinguishing between the engine's no-load and loaded states, a differentiated approach is used to correct the initial torque. For example, under loaded conditions, in addition to considering the engine speed difference and coolant temperature, the influence of the engine load on torque correction is also considered. This allows the target torque to better match the engine's actual operating conditions, effectively improving the accuracy of idle speed control, ensuring smooth and reliable engine operation, and thus guaranteeing vehicle idle stability.

[0009] In one possible implementation, the rotational speed data includes the target rotational speed and the actual rotational speed, the load data includes the generator's required torque, and the water temperature data includes the engine's coolant temperature. The process of correcting the initial torque based on the engine's speed data, load data, and coolant temperature data to obtain the target torque includes: The speed gradient is obtained based on the actual speed of the engine; The feedback correction torque is obtained based on the speed difference between the target speed and the actual speed of the engine, the speed gradient, and the torque required by the generator. The friction correction torque is determined based on the speed difference and the coolant temperature; The target torque is obtained by summing the initial torque, the feedback correction torque, and the friction correction torque.

[0010] Here, under engine load, the feedback correction torque, derived from the combined engine speed difference, speed gradient, and generator torque demand, can suppress speed disturbances caused by load fluctuations and quickly correct speed deviations. Based on the speed difference and coolant temperature, a friction correction torque is determined, which can adaptively compensate for friction losses in both cold and hot engine states. The target torque is obtained by superimposing the initial torque, feedback correction torque, and friction correction torque, which effectively improves idle speed control accuracy, ensures smooth and reliable engine operation under load, and thus enhances vehicle idle speed stability.

[0011] In one possible implementation, obtaining the feedback correction torque based on the speed difference between the engine's target speed and actual speed, the speed gradient, and the generator's required torque includes: The proportional torque is obtained based on the speed difference, the generator required torque, and a preset first correspondence between the speed difference, the generator required torque, and the proportional torque. Based on the speed difference, the generator required torque, and the preset second correspondence between the speed difference, the generator required torque and the integral correction coefficient, the integral correction coefficient is obtained, and the integral torque is obtained by multiplying the speed difference and the integral correction coefficient. Based on the speed gradient and the engine's moment of inertia, the engine's moment of inertia torque is obtained. Based on the moment of inertia torque, the generator's required torque, and a preset third correspondence between the moment of inertia torque, the generator's required torque, and the differential torque, the differential torque is obtained. The sum of the proportional torque, the integral torque, and the differential torque is used as the feedback correction torque.

[0012] In this embodiment, a proportional torque is determined based on the speed difference and the generator's required torque to quickly correct instantaneous speed deviation. An integral torque is obtained based on the speed difference and the generator's required torque to eliminate steady-state speed deviation. A differential torque is obtained based on the speed gradient, moment of inertia, and the generator's required torque to suppress speed overshoot and oscillation. The three are superimposed to obtain a feedback correction torque, which can effectively suppress load changes and speed fluctuations.

[0013] In one possible implementation, the feedback correction torque includes integral torque; The determination of the friction correction torque based on the speed difference and the coolant temperature includes: Based on the coolant temperature, a preset speed difference threshold is determined, and it is determined whether the speed difference is less than the preset speed difference threshold. If the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque is assigned to the friction torque self-learning value, and the assigned friction torque self-learning value is used as the friction correction torque. If the speed difference is greater than or equal to the preset speed difference threshold, the friction torque self-learning value will be used as the friction correction torque.

[0014] Here, under stable engine operating conditions, the self-learned friction torque value is updated using integral torque, accurately reflecting the actual frictional resistance deviation level of the engine. When the operating conditions do not yet meet the learning requirements, the already learned friction torque self-learned value is directly used as the friction correction torque, ensuring the continuity and stability of friction compensation. In this way, precise adaptive learning and compensation of the friction torque self-learned value are achieved.

[0015] In one possible implementation, determining the preset speed difference threshold based on the coolant temperature includes: If the coolant temperature is greater than the preset temperature threshold, then the preset speed difference threshold is determined to be the hot engine speed difference threshold. If the coolant temperature is less than or equal to the preset temperature threshold, then the preset speed difference threshold is determined to be the cold engine speed difference threshold. Wherein, the cold engine speed difference threshold is greater than the hot engine speed difference threshold.

[0016] In this embodiment, the cold engine speed difference threshold is set to be greater than the hot engine speed difference threshold. This takes into account the large fluctuations in engine speed during cold operation and avoids situations where the self-learning conditions cannot be met due to large fluctuations in normal engine speed, thus preventing the effective updating of the cold engine friction torque self-learning value. At the same time, using a smaller speed difference threshold during hot engine operation allows for more accurate identification of the engine's stable operating conditions, improving the accuracy and reliability of the hot engine friction torque self-learning value.

[0017] In one possible implementation, if the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque is assigned to the friction torque self-learning value, and the assigned friction torque self-learning value is used as the friction correction torque, including: If the coolant temperature is greater than the preset temperature threshold and the speed difference is less than the preset speed difference threshold, then the integral torque in the feedback correction torque is assigned to the self-learning value of the thermal engine friction torque, and the assigned self-learning value of the thermal engine friction torque is used as the friction correction torque. If the coolant temperature is less than or equal to a preset temperature threshold, and the speed difference is less than the preset speed difference threshold, then the integral torque in the feedback correction torque is assigned to the cold engine friction torque self-learning value, and the assigned cold engine friction torque self-learning value is used as the friction correction torque.

[0018] Here, because the frictional resistance of the engine differs greatly between cold and hot states, the self-learning value of frictional torque must be learned and updated separately for cold and hot states to adapt to the frictional characteristics of the engine at different temperatures and ensure the accuracy of the frictional correction torque.

[0019] In one possible implementation, the powertrain components include a clutch and a generator; the generator includes a first generator and a second generator; the load data includes the generator's required torque. Determining the engine load state based on the state of the vehicle's powertrain components and the load data includes: If the generator configured in the vehicle is the first generator, then the load state of the engine is determined according to the state of the clutch and the torque required by the generator; If the generator configured in the vehicle is a second generator, then the load state of the engine is determined based on the state of the clutch; If the vehicle is equipped with a clutch, the first generator is located between the engine and the clutch; if the vehicle is not equipped with a clutch, the first generator is located between the engine and the vehicle's transmission. The second generator is located between the clutch and the transmission, or integrated inside the transmission.

[0020] In this embodiment, based on the structural characteristics of different types of generators in vehicle configurations, the load status is determined by combining the clutch status with the generator's required torque in a differentiated manner. This can adapt to the load transmission characteristics under different power transmission architectures, effectively improve the accuracy and applicability of engine load status identification, and provide a reliable basis for subsequent differentiated determination of target torque and idle speed control.

[0021] In one possible implementation, determining the engine load state based on the clutch state and the generator's required torque includes: If the clutch is in an unconfigured or disengaged state, and the generator requires a preset torque, then the engine's load state is determined to be unloaded; otherwise, the load state is determined to be loaded. Determining the engine load state based on the state of the clutch includes: If the clutch is disengaged, the engine load state is determined to be unloaded; otherwise, it is determined whether the vehicle's drive mode is series mode or direct drive mode, and if the drive mode is series mode or direct drive mode, the load state is determined to be loaded.

[0022] Here, considering the structural characteristics of vehicles equipped with the first generator, the engine load status is comprehensively judged by combining the clutch status and the generator's required torque. This can accurately distinguish between no-load and loaded states, effectively avoiding identification errors caused by a single judgment criterion, and improving the accuracy and reliability of load status determination.

[0023] Furthermore, by combining the clutch status with the vehicle's drive mode, the engine load status can be determined, which can accurately adapt to the power transmission architecture of the second generator, effectively improving the accuracy of load status identification and avoiding misjudgment.

[0024] In one possible implementation, the speed data includes the actual speed, and the load data includes the generator's required torque; The step of obtaining the initial torque of the engine based on the engine speed data and load data includes: Obtain the fourth pre-defined relationship between engine speed, engine load and friction torque, and the fifth pre-defined relationship between engine speed, exhaust and intake pressure difference and pumping loss torque. The friction torque is determined based on the actual engine speed, engine load, and the fourth correspondence; the pumping loss torque is determined based on the actual engine speed, exhaust-intake pressure difference, and the fifth correspondence. The initial torque of the engine is obtained based on the friction torque, the pumping loss torque, and the generator required torque.

[0025] Here, the friction torque and pumping loss torque are determined based on the engine's actual speed, engine load, and exhaust-intake pressure difference, and then superimposed with the generator's required torque. This fully considers the engine's internal resistance losses and external load demands, resulting in a feedforward torque that matches the engine's actual operating conditions. This provides a precise and reasonable benchmark for subsequent load-based torque correction. Furthermore, based on preset fourth and fifth correspondences, no complex calculations are required, allowing for rapid and accurate matching of the friction torque and pumping loss torque under the engine's current operating conditions, thus improving response speed.

[0026] Secondly, embodiments of this application provide an engine control device, including: The module is used to obtain the initial torque of the engine based on the engine speed data and load data when the vehicle enters the idle activation state.

[0027] The determination module is used to determine the load state of the engine based on the state of the powertrain components of the vehicle and the load data.

[0028] The correction module is used to correct the initial torque based on the load state, as well as the engine speed data and load data, to obtain the target torque.

[0029] A control module is used to control the engine according to the target torque.

[0030] Thirdly, embodiments of this application provide a vehicle including a memory and a controller, wherein the memory stores a computer program that can run on the controller, and the controller executes the computer program to implement the engine control method as described in any of the first aspects.

[0031] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a controller, implements the engine control method as described in any of the first aspects.

[0032] It is understood that the beneficial effects of the second to fourth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here.

[0033] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this specification. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of an application scenario provided by an embodiment of this application; Figure 2 This is a schematic flowchart of an engine control method provided in an embodiment of this application; Figure 3 This is a schematic flowchart of an engine control method provided in another embodiment of this application; Figure 4 This is a schematic diagram of the structure of an engine control device provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application. Detailed Implementation

[0036] The present application will be described more clearly below with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the function of the present application, but do not limit the present application in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present application. These all fall within the protection scope of the present application.

[0037] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0038] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0039] In the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0040] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0041] Furthermore, the term "multiple" mentioned in the embodiments of this application should be interpreted as two or more.

[0042] When a vehicle is idling, the engine needs to be controlled to keep the engine speed stable at the target speed, thereby ensuring vehicle idling stability and reducing problems such as vehicle vibration, increased noise, and increased fuel consumption caused by unstable idling.

[0043] For traditional gasoline vehicles, the engine's idle speed control is usually based on the vehicle's driving status. For example, by identifying the parking gear (P / N) and driving gear (D / R), the idle speed control is achieved by distinguishing between parking and driving states.

[0044] However, the applicant's research found that hybrid vehicles operate under more complex and diverse conditions. Simply differentiating between parking and driving states for engine idling control can easily lead to poor vehicle idling stability. Therefore, the idling control strategies of traditional gasoline vehicles are ill-suited for hybrid vehicles. These hybrid vehicles include hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs).

[0045] Based on the above issues, the applicant further discovered that for hybrid vehicles, the vehicle's idling speed includes conditions such as parking generator generation and catalytic converter heating, while the driving idling speed may be in series mode, direct drive mode, or E-IDLE mode (Economic Idle mode). In series mode, the engine only drives the generator and does not directly drive the wheels; in direct drive mode, the engine directly drives the wheels; and in E-IDLE mode, the engine is idling while the generator is not generating electricity. In parking generator generation, catalytic converter heating, series mode, and direct drive mode, the engine is under high load. In E-IDLE mode, the engine is under no-load. Compared to no-load operation, under high load, load changes directly affect the engine's speed stability and require greater engine output torque to stabilize the engine speed at the target speed.

[0046] Therefore, the applicant further considered that if the engine load state could be differentiated when the vehicle enters the idling activation state, and differentiated control strategies could be adopted for idling control under different load states, it would be better suited to the operating characteristics of hybrid vehicles. Specifically, based on the initial torque of the engine, the initial torque could be modified in a differentiated manner according to different engine load states, combined with the engine load magnitude, speed, etc., to obtain the target torque suitable for the current load state. Subsequent idling control based on the target torque can achieve more stable idling control that better reflects the actual operating conditions of hybrid vehicles.

[0047] In other words, in the embodiments of this application, when the vehicle enters the idle activation state, the initial torque of the engine is first obtained based on the engine speed data and load data. Then, based on the state of the powertrain components in the vehicle and the aforementioned load data, the engine load state is determined. Furthermore, based on the load state, as well as the engine speed and load data, the initial torque is corrected to obtain the target torque. Finally, the engine is controlled according to the target torque. Thus, firstly, the target torque is determined using a differentiated approach based on different engine load states to control the engine's idle speed, which is more suitable for the operating conditions of hybrid vehicles. Secondly, when obtaining the target torque, the engine load and speed are comprehensively considered, and the initial torque is corrected to obtain a target torque that matches the current load state. Therefore, when controlling the engine with the target torque, idle speed control that is more closely aligned with the actual operating conditions of hybrid vehicles can be achieved, effectively improving vehicle idle stability and reducing issues such as vehicle vibration, increased noise, and increased fuel consumption.

[0048] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0049] First refer to Figure 1 , Figure 1 The illustration shows an application scenario diagram provided according to an embodiment of this application. The equipment involved in the application scenario may include a controller and an engine.

[0050] When the vehicle enters the idle activation state, the controller obtains the initial torque of the engine based on the engine speed data and load data, and determines the engine load state based on the state of the vehicle's powertrain components and the aforementioned load data. Then, based on the load state and the engine speed and load data, the controller corrects the initial torque and controls the engine according to the obtained target torque.

[0051] Optionally, the aforementioned controller can be an in-vehicle controller, an external controller, or a combination of both. It is a hardware device with data storage, processing, and analysis functions. Taking an in-vehicle controller as an example, it can be an Electronic Control Unit (ECU), etc.

[0052] For example, the device in this application scenario may also include multiple sensors, such as a speed sensor and a temperature sensor. The speed sensor is used to collect the actual engine speed in the vehicle, and the temperature sensor is used to collect the engine's coolant temperature.

[0053] The following is combined Figure 1 Application scenarios, refer to Figures 2-3This application describes an engine control method provided according to exemplary embodiments. It should be noted that the above application scenarios are shown only to facilitate understanding of the spirit and principles of this application, and the embodiments of this application are not limited in any way. Rather, the embodiments of this application can be applied to any applicable scenario.

[0054] refer to Figure 2 , Figure 2 This is a schematic flowchart of an engine control method provided in an embodiment of this application. Figure 2 As shown, the method in the embodiments of this application may include: Step 201: When the vehicle enters the idle activation state, the initial torque of the engine is obtained based on the engine speed data and load data.

[0055] For example, when a vehicle enters idle activation mode, engine idle speed control is required to ensure vehicle idle stability. The vehicle's drive mode, accelerator pedal opening, and clutch status are acquired. If the drive mode is series mode, direct drive mode, and accelerator pedal opening is 0, or the clutch is disengaged or not engaged, and the engine is running, then the vehicle is determined to have entered idle activation mode.

[0056] In some embodiments, the engine speed data may include the actual speed, and the load data may include the generator required torque. When obtaining the initial torque of the engine, a preset fourth correspondence between the engine speed, engine load, and friction torque, as well as a preset fifth correspondence between the engine speed, exhaust-intake pressure difference, and pumping loss torque, can be obtained. The friction torque is determined based on the actual engine speed, engine load, and the fourth correspondence. The pumping loss torque is determined based on the actual engine speed, exhaust-intake pressure difference, and the fifth correspondence. Then, the initial torque of the engine is obtained based on the above-mentioned friction torque, pumping loss torque, and generator required torque.

[0057] Among them, the exhaust-intake pressure difference is the difference between the exhaust side pressure and the intake side pressure of the engine. The fourth correspondence can be obtained from a large number of output torque-related tests conducted on engines of different vehicles at different speeds and engine loads under idle conditions. The fifth correspondence can be obtained from a large number of output torque-related tests conducted on engines of different vehicles at different speeds and exhaust-intake pressure differences under idle conditions.

[0058] The frictional torque in the initial torque is used to overcome the mechanical frictional resistance generated by various moving parts inside the engine, such as pistons, crankshafts, and bearings, during operation. It is the torque required to maintain the engine's rotation. The pumping loss torque in the initial torque is used to overcome the pumping resistance generated by the gas flow through the intake and exhaust systems and the pressure changes in the cylinders during the intake and exhaust processes. It is the torque required to maintain normal gas exchange in the engine. Therefore, the initial torque includes frictional torque and pumping loss torque to offset the engine's own operating resistance and maintain stable engine operation. The actual engine speed directly affects the friction intensity of moving parts and the magnitude of intake pumping loss. Engine load reflects the throttle opening and the ability of the air-fuel mixture in the cylinder to perform work, indirectly affecting the internal frictional losses and pumping conditions of the engine. The exhaust-intake pressure difference reflects the degree of pumping loss caused by intake throttling and exhaust back pressure. These parameters can comprehensively and accurately characterize the current internal resistance state of the engine. The generator demand torque in the initial torque is mainly used to meet the power demand of the generator. When the vehicle is idling, the most important external load on the engine is the generator's power generation. Therefore, the generator demand torque can characterize the engine's load. Therefore, based on the above parameters, the initial torque that closely matches the actual operating state of the engine can be quickly estimated.

[0059] In this embodiment, the friction torque and pumping loss torque are determined based on the engine's actual speed, engine load, and exhaust-intake pressure difference, and then superimposed with the generator's required torque. This fully considers the engine's internal resistance losses and external load demands, resulting in a feedforward torque that matches the engine's actual operating conditions. This provides a precise and reasonable benchmark for subsequent load-based torque correction. Furthermore, based on preset fourth and fifth correspondences, no complex calculations are required, allowing for rapid and accurate matching of the friction torque and pumping loss torque under the engine's current operating conditions, thus improving response speed.

[0060] Step 202: Determine the engine load status based on the status of the vehicle's powertrain components and the engine load data.

[0061] Optionally, the powertrain system components may include a clutch and a generator. The states of the powertrain system components include configuration state, operating state, and type state. Configuration state indicates whether the vehicle is equipped with the corresponding component; operating state indicates the current operating state of the corresponding component; and type state indicates the type of the corresponding component. Load states include no-load state and loaded state. No-load state indicates that the engine only overcomes its own operating resistance, with no external load or negligible external load. Loaded state indicates that the engine, in addition to overcoming its own resistance, also needs to output torque to meet the load requirements of power generation, driving, or other auxiliary components.

[0062] As mentioned above, compared to the unloaded state, the load change under the loaded state directly affects the stability of the engine speed, and a larger output torque is required to stabilize the engine speed at the target speed. Therefore, in this embodiment, the load state of the engine is first determined so that the initial torque can be corrected in a differentiated manner for different load states.

[0063] In this embodiment, the state of the power transmission system components directly determines the engine's power output target and load connection status, while the engine's load data reflects the actual size of the current load. Therefore, by combining the two for comprehensive judgment, it is possible to accurately determine whether the engine is idling under no-load or under load, that is, to accurately identify the current load status of the engine, providing a reliable basis for subsequent differential determination of target torque and idle speed control.

[0064] Step 203: Based on the load condition, engine speed data, and load data, correct the initial torque to obtain the target torque.

[0065] The speed data can include the speed difference between the engine's target speed and the actual speed, while the load data represents the engine's load, such as the torque required by the generator.

[0066] In this embodiment, when correcting the initial torque, a feedback correction process can be employed. This process is based on the deviation between the engine's target speed and actual speed to obtain a feedback correction torque, which is then used to correct the initial torque. This allows for direct closed-loop correction of the initial torque, enabling the actual speed to quickly track and stabilize at the target speed. The feedback correction process can include proportional-integral-derivative (PID) correction, fuzzy correction, and adaptive correction methods, among others; specific limitations are not specified here.

[0067] Compared to the no-load state, under load, load changes directly affect the engine's speed stability, and the engine requires greater output torque. Therefore, under load, the feedback correction process also needs to consider the impact of the engine load on the output torque, that is, the impact of the engine load on torque correction, in order to accurately correct the torque. Under no-load conditions, almost no external load acts on the engine. At this time, torque correction only needs to focus on the speed difference between the target speed and the actual speed. Therefore, in this embodiment, different engine load states are distinguished, and feedback correction processing is performed on the initial torque based on the engine speed difference and load magnitude to obtain the target torque.

[0068] For example, under load, the feedback correction torque can be obtained based on the speed difference between the engine's target speed and actual speed, the engine load, and a preset correspondence between speed difference, load, and torque. Under no-load conditions, since no external load is involved, the feedback correction torque can be obtained based on the speed difference and the preset correspondence between speed difference and torque. The aforementioned correspondence between speed difference, load, and torque can be obtained through numerous tests on the output torque of different vehicles' engines under different speed differences and loads at idle speed under load. Similarly, the aforementioned correspondence between speed difference and torque can be obtained through numerous tests on the output torque of different vehicles' engines under different speed differences at idle speed under no-load conditions.

[0069] Step 204: Control the engine according to the target torque.

[0070] After the initial torque is corrected by feedback to obtain the target torque, the engine output torque is controlled by the target torque to keep the actual engine speed stable at the target speed and improve the vehicle's idling stability.

[0071] The engine control method provided in this application, when the vehicle enters the idle activation state, firstly obtains the initial torque of the engine based on the engine speed data and load data. Then, based on the state of the powertrain components in the vehicle and the aforementioned load data, the engine load state is determined. Subsequently, based on the load state, engine speed data, and load data, the initial torque is corrected to obtain the target torque. Finally, the engine is controlled according to the target torque. Thus, firstly, the target torque is determined in a differentiated manner based on different engine load states to control the engine idle speed, which is more suitable for the operating conditions of hybrid vehicles. Secondly, when obtaining the target torque, the initial torque is corrected by comprehensively considering the engine load and speed, enabling the acquisition of a target torque that matches the current load state. Therefore, when controlling the engine with the target torque, idle speed control that is more closely aligned with the actual operating conditions of hybrid vehicles can be achieved, effectively improving vehicle idle stability and reducing issues such as vehicle vibration, increased noise, and increased fuel consumption.

[0072] In addition, in order to further improve the accuracy of the initial torque correction so as to improve the vehicle's idling stability when controlling the engine with the corrected target torque, this embodiment also considers further refining the feedback correction process and correcting the portion of the initial torque that overcomes frictional resistance.

[0073] Figure 3 This is a schematic flowchart of an engine control method provided in another embodiment of this application. For example... Figure 3 As shown, the method in the embodiments of this application may include: Step 301: When the vehicle enters the idle activation state, the initial torque of the engine is obtained based on the engine speed data and load data.

[0074] Here, the specific implementation method and principle of step 301 can be referred to the relevant description in the foregoing embodiments, and will not be repeated here.

[0075] Step 302: Determine the engine load status based on the status of the vehicle's powertrain components and the engine load data.

[0076] As mentioned above, load conditions include no-load and loaded conditions. Powertrain system components may include clutches and generators. The states of powertrain system components include configuration state, operating state, and type state, such as whether the vehicle is equipped with a clutch (configuration state), whether the clutch is disengaged when it is equipped (operating state), and whether the generator is a P1 motor or a P2 motor (type state).

[0077] The aforementioned generator may include a first generator and a second generator. The first generator may be a P1 motor, and the second generator may be a P2 motor or a P2.5 motor. If the vehicle is equipped with a clutch, the first generator, i.e., the P1 motor, is located between the engine and the clutch. If the vehicle is not equipped with a clutch, the first generator is located between the engine and the vehicle's transmission. When the second generator is a P2 motor, it is located between the clutch and the transmission; when the second generator is a P2.5 motor, it is integrated inside the transmission.

[0078] As mentioned earlier, engine load data includes generator demand torque, which characterizes the magnitude of the engine load or the majority of the load. This is because when the vehicle is idling, the engine's primary external load is generated by the generator, thus generator demand torque can be used to represent changes in engine load. Generator demand torque is typically determined by the Hybrid Control Unit (HCU) based on the difference between the target SOC (State of Charge) and the actual SOC of the battery, vehicle thermal management requirements, etc. For example, the HCU obtains the generator demand torque based on the aforementioned parameters, as well as the preset correspondence between the target SOC and the actual SOC of the battery, vehicle thermal management requirements, and generator demand torque, and then sends it to the controller.

[0079] In some embodiments, when determining the engine load state, the engine load state can be determined based on the clutch state and the generator's required torque when the generator configured in the vehicle is a first generator, and based on the clutch state when the generator configured in the vehicle is a second generator.

[0080] The state of the powertrain components, specifically the clutch and generator, directly determines the engine's power output and load engagement. Different combinations of the clutch and generator result in different powertrain architectures, and the generator's required torque itself represents the engine's load. Therefore, this embodiment employs differentiated load state judgment logic based on the generator's location and power transmission path.

[0081] It should be noted that a first generator and a second generator cannot be installed in the vehicle at the same time.

[0082] In this embodiment, based on the structural characteristics of different types of generators in vehicle configurations, the load status is determined by combining the clutch status with the generator's required torque in a differentiated manner. This can adapt to the load transmission characteristics under different power transmission architectures, effectively improve the accuracy and applicability of engine load status identification, and provide a reliable basis for subsequent differentiated determination of target torque and idle speed control.

[0083] In some embodiments, the generator configured in the vehicle is a first generator. When determining the load state of the engine based on the state of the clutch and the required torque of the generator, it can be determined whether the state of the clutch is unconfigured or disengaged, and whether the required torque of the generator is a preset value. If the state of the clutch is unconfigured or disengaged, and the required torque of the generator is a preset value, then the load state of the engine is determined to be an unloaded state; otherwise, the load state is determined to be a loaded state.

[0084] The P1 motor is directly connected to the engine, and its load can be directly transmitted to the engine. If the clutch is disengaged or there is no clutch in the vehicle, the engine is disconnected from the subsequent transmission components such as the gearbox. At this time, the engine can only bear the load from the P1 motor. Therefore, when the generator's required torque is a preset value such as 0, the engine has no external load and is determined to be in an unloaded state.

[0085] Conversely, if the vehicle is equipped with a clutch and the clutch is not disengaged (i.e., the clutch is engaged), or if the generator requires torque that is not zero, then the load condition is determined to be a loaded condition.

[0086] In this embodiment, considering the structural characteristics of the vehicle equipped with the first generator, the load status of the engine is comprehensively judged by combining the state of the clutch and the torque required by the generator. This can accurately distinguish between no-load and loaded states, effectively avoid identification errors caused by a single judgment criterion, and improve the accuracy and reliability of load status determination.

[0087] In some embodiments, the generator configured in the vehicle is a second generator. When determining the load state of the engine based on the state of the clutch, it can be determined whether the state of the clutch is disengaged. If the state of the clutch is disengaged, the load state of the engine is determined to be unloaded. Otherwise, it is determined whether the driving mode of the vehicle is a series mode or a direct drive mode. If the driving mode is a series mode or a direct drive mode, the load state is determined to be loaded.

[0088] The P2 motor is located between the clutch and the gearbox, while the P2.5 motor is integrated inside the gearbox. Whether the load can be transmitted to the engine depends entirely on the working state of the clutch. When the clutch is disengaged, the engine is disconnected from the second generator (P2 motor or P2.5 motor) and subsequent powertrain. The engine is not affected by the motor side, and the engine's power cannot be transmitted to the second generator. Therefore, the engine is in an unloaded state.

[0089] When the clutch is engaged, the engine is coupled to the powertrain. If the vehicle is operating in series mode, the engine needs to drive the generator to generate electricity. If the vehicle is operating in direct drive mode, the engine needs to directly drive the vehicle. In both cases, the engine is under external load, so the engine is considered to be under load.

[0090] In this embodiment, by combining the state of the clutch with the driving mode of the vehicle, the load state of the engine is determined, which can accurately adapt to the power transmission architecture of the second generator, effectively improve the accuracy of load state identification, and avoid misjudgment.

[0091] Step 303: If the load condition is no-load, the initial torque is corrected based on the engine speed data and water temperature data to obtain the target torque. If the load condition is loaded, the initial torque is corrected based on the engine speed data, load data and water temperature data to obtain the target torque.

[0092] Here, the engine speed data can include the target speed and the actual speed, and the coolant temperature data can include the engine coolant temperature. The target speed can be determined based on the vehicle's power generation requirements, as well as noise, vibration, and harshness (NVH) and the engine's economic speed range.

[0093] This embodiment can employ feedback correction processing, which directly performs closed-loop correction on the initial torque based on the deviation between the engine's target speed and actual speed, so that the actual speed quickly tracks and stabilizes at the target speed. Here, feedback correction processing can include feedback correction methods such as PID correction, fuzzy correction, and adaptive correction, and no specific limitations are imposed here.

[0094] Furthermore, as mentioned above, the initial torque includes the torque required to overcome engine friction resistance. However, with engine use, the actual friction resistance changes due to wear, aging, and changes in oil condition. Therefore, in this embodiment, the portion of the initial torque used to overcome friction resistance can be corrected. Since the friction resistance differs significantly between cold and hot engine states due to differences in oil viscosity, this embodiment considers correcting the portion of the initial torque used to overcome friction resistance based on the coolant temperature, which characterizes the engine's cold and hot states.

[0095] As mentioned above, compared to the no-load state, load changes directly affect the engine's speed stability under load, and the engine requires greater output torque. Therefore, under load, the feedback correction process also needs to consider the impact of the engine load on the output torque, that is, the impact of the engine load on torque correction. Under no-load conditions, almost no external load acts on the engine, so the feedback correction process only needs to focus on the engine speed difference.

[0096] Therefore, this embodiment uses a differentiated approach to correct the initial torque under different engine load conditions, and also corrects the portion of the initial torque that overcomes frictional resistance.

[0097] In this embodiment, by distinguishing between the engine's no-load and loaded states, a differentiated approach is used to correct the initial torque. For example, under loaded conditions, in addition to considering the engine speed difference and coolant temperature, the influence of the engine load on torque correction is also considered. This allows the target torque to better match the engine's actual operating conditions, effectively improving the accuracy of idle speed control, ensuring stable and reliable engine operation, and thus guaranteeing vehicle idle stability.

[0098] The following embodiments describe in detail how to obtain the target torque when the engine is under load.

[0099] In some embodiments, when the engine is under load, when correcting the initial torque to obtain the target torque, the engine speed gradient can be obtained based on the actual engine speed. The feedback correction torque can be obtained based on the speed difference between the target engine speed and the actual engine speed, the speed gradient, and the torque required by the generator. The friction correction torque can be determined based on the speed difference and the coolant temperature. Then, the target torque is obtained by summing the initial torque, the feedback correction torque, and the friction correction torque.

[0100] In this embodiment, the engine speed gradient can reflect the speed change trend. Combined with the difference between the target speed and the actual speed, the speed deviation can be corrected. Based on the generator's required torque, the influence of load disturbance on the speed can be eliminated. Therefore, by combining the above parameters and performing feedback correction processing, feedback correction torque is obtained.

[0101] As mentioned above, in practical applications, with the increase in engine usage time, factors such as component wear and oil aging will occur, leading to changes in the frictional resistance during engine operation. Therefore, it is necessary to compensate for and correct the frictional torque; this correction value is the frictional correction torque. When correcting the portion of the initial torque that overcomes frictional resistance, a self-learning value for the frictional torque can be set. The internal frictional resistance of the engine differs significantly between cold and hot engine states; therefore, the learned frictional correction torque should be assigned to the corresponding self-learning values ​​for cold and hot engine states, respectively. Furthermore, the true frictional correction torque can only be accurately learned and obtained when the difference between the target speed and the actual speed is small and the engine idle speed is stable. Therefore, the frictional correction torque is obtained by combining the engine coolant temperature and the speed difference.

[0102] In this embodiment, under engine load, the feedback correction torque, obtained by combining the engine speed difference, speed gradient, and generator torque demand, can suppress speed disturbances caused by load fluctuations and quickly correct speed deviations. Based on the speed difference and coolant temperature, a friction correction torque is determined, which can adaptively compensate for friction losses in both cold and hot engine states. The target torque is obtained by superimposing the initial torque, feedback correction torque, and friction correction torque, which effectively improves idle speed control accuracy, ensures smooth and reliable engine operation under load, and thus improves vehicle idle speed stability.

[0103] In some embodiments, the feedback correction process employs PID correction. When the feedback correction torque is obtained, it can be... A1. Based on the speed difference, the generator's required torque, and the preset first correspondence between the speed difference, the generator's required torque, and the proportional torque, the proportional torque is obtained.

[0104] A2. Based on the speed difference, generator required torque, and the second correspondence between the preset speed difference, generator required torque and integral correction coefficient, the integral correction coefficient is obtained, and the integral torque is obtained by multiplying the speed difference and the integral correction coefficient.

[0105] A3. Based on the speed gradient and the engine's moment of inertia, the engine's moment of inertia torque is obtained. Based on the moment of inertia torque, the generator's required torque, and the preset third correspondence between the moment of inertia torque, the generator's required torque, and the differential torque, the differential torque is obtained.

[0106] A4. The sum of the proportional torque, integral torque, and derivative torque is used as the feedback correction torque.

[0107] Here, proportional torque is essentially the instantaneous response torque to the speed difference and engine load, used to quickly suppress speed fluctuations and compensate for load disturbances, improving the response speed and stability of idle speed control. Integral torque is essentially the torque that cumulatively compensates for steady-state deviations by combining the speed difference and load magnitude, mainly used to eliminate steady-state speed deviations caused by friction, load, and other factors under load at idle speed, so that the actual engine speed is stabilized at the target speed. Differential torque is essentially a predictive adjustment torque based on the speed change trend, moment of inertia, and engine load magnitude, used to predict and suppress speed overshoot and dynamic fluctuations, improving the smoothness of idle speed control.

[0108] In step A2, after obtaining the integral correction coefficient, the integral correction amount for the current cycle is obtained by multiplying the speed difference by the integral correction coefficient. This integral correction amount is then added to the integral torque of the previous cycle to obtain the integral torque for the current cycle. This is because the integral torque is a gradually accumulating and continuously correcting steady-state correction. Adding the integral correction amount of the current cycle to the integral result of the previous cycle is necessary to continuously eliminate steady-state deviations.

[0109] In step A3, the speed gradient represents the speed change trend, and the moment of inertia is the engine's own rotational inertia. The moment of inertia torque obtained by multiplying the two reflects the inertial torque required to overcome the trend. The generator demand torque reflects the load disturbance. Combining the moment of inertia torque and the generator demand torque yields the differential torque, which takes into account both the speed change trend and the load, thereby achieving predictive damping of speed fluctuations and effectively suppressing speed overshoot and oscillation.

[0110] The first correspondence mentioned above can be obtained from numerous proportional torque correlation tests conducted on generators of different vehicles at different speed differences and with different generator torque requirements under idling conditions. Similarly, the second correspondence mentioned above can be obtained from numerous integral correction coefficient correlation tests conducted on generators of different vehicles at different speed differences and with different generator torque requirements. The third correspondence mentioned above can be obtained from numerous differential torque correlation tests conducted on generators of different vehicles at different moments of inertia torques and with different generator torque requirements.

[0111] In this embodiment, a proportional torque is determined based on the speed difference and the generator's required torque to quickly correct instantaneous speed deviation. An integral torque is obtained based on the speed difference and the generator's required torque to eliminate steady-state speed deviation. A differential torque is obtained based on the speed gradient, moment of inertia, and the generator's required torque to suppress speed overshoot and oscillation. The three are superimposed to obtain a feedback correction torque, which can effectively suppress load changes and speed fluctuations.

[0112] In some embodiments, when determining the friction correction torque, it is possible to B1. Determine the preset speed difference threshold based on the coolant temperature, and determine whether the speed difference is less than the preset speed difference threshold.

[0113] B2. If the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque will be assigned to the friction torque self-learning value, and the assigned friction torque self-learning value will be used as the friction correction torque.

[0114] B3. If the speed difference is greater than or equal to the preset speed difference threshold, the self-learned friction torque value will be used as the friction correction torque.

[0115] When the speed difference between the target engine speed and the actual engine speed is less than a preset speed difference threshold, it indicates that the engine is operating smoothly. At this point, both the proportional torque and the derivative torque are close to zero. The integral torque, as a steady-state compensation accumulated over a long period, plays a major compensating role. Since the speed deviation is mainly dominated by the internal frictional resistance of the engine, the integral torque can accurately reflect the current frictional resistance deviation level of the engine. The integral torque is then assigned to the frictional torque self-learning value and used as the frictional correction torque. The frictional torque self-learning value is stored in the controller.

[0116] When the speed difference is large, the engine operating condition is unstable, and the integral torque is in a dynamic adjustment process, containing many dynamic adjustment components. It cannot represent the true friction resistance level. Therefore, the friction torque self-learning value is not updated at this time to avoid learning errors and ensure the reliability of the friction correction torque.

[0117] It is understood that the speed difference here refers to the absolute value of the speed difference. This embodiment sets an initial friction torque self-learning value, which is used as the friction correction torque before the friction torque self-learning value is updated for the first time, or in the initial stage of idle speed control.

[0118] In this embodiment, under stable engine operating conditions, the self-learned friction torque value is updated using integral torque, which accurately reflects the actual frictional resistance deviation level of the engine. When the operating conditions do not yet meet the learning conditions, the already learned self-learned friction torque value is directly used as the friction correction torque, ensuring the continuity and stability of friction compensation. Thus, accurate adaptive learning and compensation of the self-learned friction torque value are achieved.

[0119] In some embodiments, when determining the preset speed difference threshold, the preset speed difference threshold can be determined as the hot engine speed difference threshold when the coolant temperature is greater than the preset temperature threshold, and as the cold engine speed difference threshold when the coolant temperature is less than or equal to the preset temperature threshold, wherein the cold engine speed difference threshold is greater than the hot engine speed difference threshold.

[0120] Here, a coolant temperature greater than a preset temperature threshold indicates the engine is in a hot-engine state, while a coolant temperature less than or equal to the preset temperature threshold indicates the engine is in a cold-engine state. Because engine speed fluctuates significantly in a cold-engine state, a larger normal speed fluctuation is permissible. This means the cold-engine speed difference threshold is greater than the hot-engine speed difference threshold. In a cold-engine state, as long as the speed difference is less than this larger threshold, the engine is considered to be operating stably, and the friction torque self-learning value can be updated normally, reducing the likelihood of ineffective updates.

[0121] In this embodiment, the cold engine speed difference threshold is set to be greater than the hot engine speed difference threshold. This takes into account the large fluctuations in engine speed during cold operation and avoids situations where the self-learning conditions cannot be met due to large fluctuations in normal engine speed, thus preventing the effective updating of the cold engine friction torque self-learning value. At the same time, using a smaller speed difference threshold during hot operation allows for more accurate identification of the engine's stable operating conditions, improving the accuracy and reliability of the hot engine friction torque self-learning value.

[0122] In some embodiments, when assigning the integral torque in the feedback correction torque to the friction torque self-learning value, the integral torque in the feedback correction torque can be assigned to the hot engine friction torque self-learning value when the coolant temperature is greater than a preset temperature threshold and the speed difference is less than a preset speed difference threshold, and the assigned hot engine friction torque self-learning value is used as the friction correction torque.

[0123] When the coolant temperature is less than or equal to the preset temperature threshold and the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque is assigned to the cold engine friction torque self-learning value, and the assigned cold engine friction torque self-learning value is used as the friction correction torque.

[0124] Here, when the engine is warm, if the speed difference is less than the warm engine speed difference threshold, that is, when the engine is operating stably, the integral torque is assigned to the self-learned value of the warm engine friction torque. When the engine is cold, if the speed difference is less than the cold engine speed difference threshold, the integral torque is assigned to the self-learned value of the cold engine friction torque.

[0125] In this embodiment, since the frictional resistance of the engine differs greatly between cold and hot states, the self-learning value of the frictional torque needs to be learned and updated separately for cold and hot states to adapt to the frictional characteristics of the engine at different temperatures and ensure the accuracy of the frictional correction torque.

[0126] For example, when the coolant temperature is greater than a preset temperature threshold and the speed difference is greater than or equal to the preset speed difference threshold of the hot engine, the self-learned value of the hot engine friction torque is used as the friction correction torque; when the coolant temperature is less than or equal to the preset temperature threshold and the speed difference is greater than or equal to the preset speed difference threshold of the cold engine, the self-learned value of the cold engine friction torque is used as the friction correction torque.

[0127] Here, we distinguish between hot and cold engine states. Under different states, when the self-learning conditions are not met, we use different friction torque self-learning values ​​as friction correction torques to adapt to the friction characteristics of the engine at different temperatures and ensure the accuracy of the friction correction torque.

[0128] The above embodiments describe in detail how to obtain the target torque when the engine is under load. The following embodiments describe how to obtain the target torque when the engine is under no-load.

[0129] In some embodiments, when the engine is in an unloaded state, when correcting the initial torque to obtain the target torque, the engine speed gradient can be obtained based on the actual engine speed. The feedback correction torque can be obtained based on the speed difference between the target engine speed and the actual engine speed and the speed gradient. The friction correction torque can be determined based on the speed difference and the coolant temperature. Then, the target torque is obtained by adding the initial torque, the feedback correction torque and the friction correction torque.

[0130] For example, when the engine is in an unloaded state and receives feedback correction torque, it can: The proportional torque is obtained based on the speed difference and the preset correspondence between the speed difference and the proportional torque.

[0131] Based on the speed difference and the preset correspondence between the speed difference and the integral correction coefficient, the integral correction coefficient is obtained, and the integral torque is obtained by multiplying the speed difference and the integral correction coefficient.

[0132] Based on the speed gradient and the engine's moment of inertia, the engine's moment of inertia torque is obtained. Based on the moment of inertia torque and the preset correspondence between the moment of inertia torque and the differential torque, the differential torque is obtained.

[0133] The sum of the proportional torque, integral torque, and derivative torque is used as the feedback correction torque.

[0134] Optionally, when the engine is in an unloaded state, the specific implementation steps for determining the friction correction torque can refer to steps B1 to B3 and related content in the aforementioned embodiments.

[0135] In this embodiment, since there is almost no external load acting on the engine when it is unloaded, there is no need to consider the generator's required torque when determining the feedback correction torque and friction correction torque. That is, different load states of the engine are distinguished, and a differentiated approach is used to perform feedback correction processing on the initial torque, as well as to correct the portion of the initial torque that overcomes frictional resistance. This results in a target torque that more closely matches the engine's actual operating conditions, effectively improving idle speed control accuracy, ensuring smooth and reliable engine operation, and ultimately guaranteeing vehicle idle stability.

[0136] The specific implementation process and principle of obtaining the feedback correction torque and friction correction torque when the engine is in an unloaded state, and then obtaining the target torque based on the initial torque, the feedback correction torque and the friction correction torque, can be referred to the relevant description of obtaining the target torque when the engine is under load in the previous embodiment, which will not be repeated here.

[0137] Step 304: Control the engine according to the target torque.

[0138] In this embodiment, after the initial torque is corrected by feedback to obtain the target torque, the engine output torque is controlled by the target torque so that the actual speed of the engine is stabilized at the target speed, thereby improving the vehicle's idling stability.

[0139] Here, the specific implementation methods and principles of steps 302 to 304 can be referred to the relevant descriptions in the foregoing embodiments, and will not be repeated here.

[0140] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0141] Figure 4 This is a schematic diagram of the structure of an engine control device provided in one embodiment of this application. Figure 4 As shown, the engine control device provided in this embodiment may include: a obtaining module 401, a determining module 402, a correcting module 403, and a control module 404.

[0142] The module 401 is used to obtain the initial torque of the engine based on the engine speed data and load data when the vehicle enters the idle activation state.

[0143] The determination module 402 is used to determine the load state of the engine based on the state of the powertrain components of the vehicle and the load data.

[0144] The correction module 403 is used to correct the initial torque based on the load state, the engine speed data, and the load data to obtain the target torque.

[0145] The control module 404 is used to control the engine according to the target torque.

[0146] In one possible implementation, the load state includes an unloaded state and a loaded state; the correction module 403 is further configured to: If the load state is an unloaded state, the initial torque is corrected based on the engine speed data and water temperature data to obtain the target torque; If the load state is a loaded state, the initial torque is corrected based on the engine speed data, load data, and water temperature data to obtain the target torque.

[0147] In one possible implementation, the rotational speed data includes the target rotational speed and the actual rotational speed, the load data includes the generator's required torque, and the coolant temperature data includes the engine's coolant temperature; the correction module 403 is further configured to: The speed gradient is obtained based on the actual speed of the engine; The feedback correction torque is obtained based on the speed difference between the target speed and the actual speed of the engine, the speed gradient, and the torque required by the generator. The friction correction torque is determined based on the speed difference and the coolant temperature; The target torque is obtained by summing the initial torque, the feedback correction torque, and the friction correction torque.

[0148] In one possible implementation, the correction module 403 is also used for: The proportional torque is obtained based on the speed difference, the generator required torque, and a preset first correspondence between the speed difference, the generator required torque, and the proportional torque. Based on the speed difference, the generator required torque, and the preset second correspondence between the speed difference, the generator required torque and the integral correction coefficient, the integral correction coefficient is obtained, and the integral torque is obtained by multiplying the speed difference and the integral correction coefficient. Based on the speed gradient and the engine's moment of inertia, the engine's moment of inertia torque is obtained. Based on the moment of inertia torque, the generator's required torque, and a preset third correspondence between the moment of inertia torque, the generator's required torque, and the differential torque, the differential torque is obtained. The sum of the proportional torque, the integral torque, and the differential torque is used as the feedback correction torque.

[0149] In one possible implementation, the feedback correction torque includes integral torque; the correction module 403 is further configured to: Based on the coolant temperature, a preset speed difference threshold is determined, and it is determined whether the speed difference is less than the preset speed difference threshold. If the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque is assigned to the friction torque self-learning value, and the assigned friction torque self-learning value is used as the friction correction torque. If the speed difference is greater than or equal to the preset speed difference threshold, the friction torque self-learning value will be used as the friction correction torque.

[0150] In one possible implementation, the determining module 402 is further used for: If the coolant temperature is greater than the preset temperature threshold, then the preset speed difference threshold is determined to be the hot engine speed difference threshold. If the coolant temperature is less than or equal to the preset temperature threshold, then the preset speed difference threshold is determined to be the cold engine speed difference threshold. Wherein, the cold engine speed difference threshold is greater than the hot engine speed difference threshold.

[0151] In one possible implementation, the determining module 402 is further used for: If the coolant temperature is greater than the preset temperature threshold and the speed difference is less than the preset speed difference threshold, then the integral torque in the feedback correction torque is assigned to the self-learning value of the thermal engine friction torque, and the assigned self-learning value of the thermal engine friction torque is used as the friction correction torque. If the coolant temperature is less than or equal to a preset temperature threshold, and the speed difference is less than the preset speed difference threshold, then the integral torque in the feedback correction torque is assigned to the cold engine friction torque self-learning value, and the assigned cold engine friction torque self-learning value is used as the friction correction torque.

[0152] In one possible implementation, the powertrain components include a clutch and a generator; the generator includes a first generator and a second generator; the load data includes the generator's required torque; the determination module 402 is further configured to: If the generator configured in the vehicle is the first generator, then the load state of the engine is determined according to the state of the clutch and the torque required by the generator; If the generator configured in the vehicle is a second generator, then the load state of the engine is determined based on the state of the clutch; If the vehicle is equipped with a clutch, the first generator is located between the engine and the clutch; if the vehicle is not equipped with a clutch, the first generator is located between the engine and the vehicle's transmission. The second generator is located between the clutch and the transmission, or integrated inside the transmission.

[0153] In one possible implementation, the determining module 402 is further used for: If the clutch is in an unconfigured or disengaged state, and the generator requires a preset torque, then the engine's load state is determined to be unloaded; otherwise, the load state is determined to be loaded.

[0154] Furthermore, if the clutch is disengaged, the engine load state is determined to be unloaded; otherwise, it is determined whether the vehicle's drive mode is series mode or direct drive mode, and if the drive mode is series mode or direct drive mode, the load state is determined to be loaded.

[0155] In one possible implementation, the speed data includes the actual speed, and the load data includes the generator's required torque; the obtaining module 401 is further configured to: Obtain the fourth pre-defined relationship between engine speed, engine load and friction torque, and the fifth pre-defined relationship between engine speed, exhaust and intake pressure difference and pumping loss torque. The friction torque is determined based on the actual engine speed, engine load, and the fourth correspondence; the pumping loss torque is determined based on the actual engine speed, exhaust-intake pressure difference, and the fifth correspondence. The initial torque of the engine is obtained based on the friction torque, the pumping loss torque, and the generator required torque.

[0156] It should be noted that the information interaction and execution process between the above-mentioned devices / units are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, and they will not be repeated here.

[0157] Figure 5 This is a schematic diagram of the structure of a vehicle provided in one embodiment of this application. Figure 5 As shown, the vehicle 500 in this embodiment includes a controller 510 and a memory 520, wherein the memory 520 stores a computer program 521 that can run on the controller 510. When the controller 510 executes the computer program 521, it implements the steps in any of the above method embodiments, for example... Figure 2Steps 201 to 204 are shown. Alternatively, when the controller 510 executes the computer program 521, it implements the functions of each module / unit in the above-described device embodiments, for example... Figure 4 The functions of modules 401 to 404 are shown.

[0158] For example, computer program 521 may be divided into one or more modules / units, one or more of which are stored in memory 520 and executed by controller 510 to complete this application. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of computer program 521 in vehicle 500.

[0159] Those skilled in the art will understand that Figure 5 This is merely an example of a vehicle and does not constitute a limitation on the vehicle. It may include more or fewer components than shown, or combinations of certain components, or different components, such as input / output devices, network access devices, buses, etc.

[0160] The controller 510 can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor.

[0161] The memory 520 can be an internal storage unit of the vehicle, such as a hard drive or memory, or an external storage device, such as a plug-in hard drive, smart media card (SMC), secure digital (SD) card, flash card, etc. The memory 520 can also include both internal and external storage devices. The memory 520 is used to store computer programs and other programs and data required by the vehicle. The memory 520 can also be used to temporarily store data that has been output or will be output.

[0162] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0163] An embodiment of this application also provides a computer-readable storage medium storing a computer program that, when executed by a controller, implements the engine control method described above.

[0164] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0165] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0166] In the embodiments provided in this application, it should be understood that the disclosed devices / vehicles and methods can be implemented in other ways. For example, the device / vehicle embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0167] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0168] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0169] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a controller, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0170] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An engine control method, characterized in that, include: When the vehicle enters the idle activation state, the initial torque of the engine is obtained based on the engine speed data and load data; The load status of the engine is determined based on the status of the powertrain components of the vehicle and the load data. Based on the load condition, as well as the engine speed and load data, the initial torque is corrected to obtain the target torque; The engine is controlled according to the target torque.

2. The engine control method according to claim 1, characterized in that, The load status includes an unloaded state and a loaded state; The step of correcting the initial torque based on the load state, engine speed data, and load data to obtain the target torque includes: If the load state is an unloaded state, the initial torque is corrected based on the engine speed data and water temperature data to obtain the target torque; If the load state is a loaded state, the initial torque is corrected based on the engine speed data, load data, and water temperature data to obtain the target torque.

3. The engine control method according to claim 2, characterized in that, The rotational speed data includes the target rotational speed and the actual rotational speed; the load data includes the generator's required torque; and the water temperature data includes the engine's coolant temperature. The process of correcting the initial torque based on the engine's speed data, load data, and coolant temperature data to obtain the target torque includes: The speed gradient is obtained based on the actual speed of the engine; The feedback correction torque is obtained based on the speed difference between the target speed and the actual speed of the engine, the speed gradient, and the torque required by the generator. The friction correction torque is determined based on the speed difference and the coolant temperature; The target torque is obtained by summing the initial torque, the feedback correction torque, and the friction correction torque.

4. The engine control method according to claim 3, characterized in that, The step of obtaining the feedback correction torque based on the speed difference between the engine's target speed and actual speed, the speed gradient, and the generator's required torque includes: The proportional torque is obtained based on the speed difference, the generator required torque, and a preset first correspondence between the speed difference, the generator required torque, and the proportional torque. Based on the speed difference, the generator required torque, and the preset second correspondence between the speed difference, the generator required torque and the integral correction coefficient, the integral correction coefficient is obtained, and the integral torque is obtained by multiplying the speed difference and the integral correction coefficient. Based on the speed gradient and the engine's moment of inertia, the engine's moment of inertia torque is obtained. Based on the moment of inertia torque, the generator's required torque, and a preset third correspondence between the moment of inertia torque, the generator's required torque, and the differential torque, the differential torque is obtained. The sum of the proportional torque, the integral torque, and the differential torque is used as the feedback correction torque.

5. The engine control method according to claim 3, characterized in that, The feedback correction torque includes integral torque; The determination of the friction correction torque based on the speed difference and the coolant temperature includes: Based on the coolant temperature, a preset speed difference threshold is determined, and it is determined whether the speed difference is less than the preset speed difference threshold. If the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque is assigned to the friction torque self-learning value, and the assigned friction torque self-learning value is used as the friction correction torque. If the speed difference is greater than or equal to the preset speed difference threshold, the self-learned friction torque value will be used as the friction correction torque.

6. The engine control method according to claim 5, characterized in that, The step of determining the preset speed difference threshold based on the coolant temperature includes: If the coolant temperature is greater than the preset temperature threshold, then the preset speed difference threshold is determined to be the hot engine speed difference threshold. If the coolant temperature is less than or equal to the preset temperature threshold, then the preset speed difference threshold is determined to be the cold engine speed difference threshold. Wherein, the cold engine speed difference threshold is greater than the hot engine speed difference threshold.

7. The engine control method according to claim 5, characterized in that, If the speed difference is less than the preset speed difference threshold, the integral torque in the feedback correction torque is assigned to the friction torque self-learning value, and the assigned friction torque self-learning value is used as the friction correction torque, including: If the coolant temperature is greater than the preset temperature threshold and the speed difference is less than the preset speed difference threshold, then the integral torque in the feedback correction torque is assigned to the self-learning value of the thermal engine friction torque, and the assigned self-learning value of the thermal engine friction torque is used as the friction correction torque. If the coolant temperature is less than or equal to a preset temperature threshold, and the speed difference is less than the preset speed difference threshold, then the integral torque in the feedback correction torque is assigned to the cold engine friction torque self-learning value, and the assigned cold engine friction torque self-learning value is used as the friction correction torque.

8. The engine control method according to any one of claims 1 to 5, characterized in that, The powertrain components include a clutch and a generator; the generator includes a first generator and a second generator; the load data includes the generator's required torque. Determining the engine load state based on the state of the vehicle's powertrain components and the load data includes: If the generator configured in the vehicle is the first generator, then the load state of the engine is determined based on the state of the clutch and the torque required by the generator; If the generator configured in the vehicle is a second generator, then the load state of the engine is determined according to the state of the clutch; If the vehicle is equipped with a clutch, the first generator is located between the engine and the clutch; if the vehicle is not equipped with a clutch, the first generator is located between the engine and the vehicle's transmission. The second generator is located between the clutch and the transmission, or integrated inside the transmission.

9. The engine control method according to claim 8, characterized in that, Determining the engine load state based on the clutch state and the generator's required torque includes: If the clutch is in an unconfigured or disengaged state, and the generator requires a preset torque, then the engine's load state is determined to be unloaded; otherwise, the load state is determined to be loaded. Determining the engine load state based on the state of the clutch includes: If the clutch is disengaged, the engine load state is determined to be unloaded; otherwise, it is determined whether the vehicle's drive mode is series mode or direct drive mode, and if the drive mode is series mode or direct drive mode, the load state is determined to be loaded.

10. The engine control method according to any one of claims 1 to 5, characterized in that, The rotational speed data includes the actual rotational speed, and the load data includes the generator's required torque. The step of obtaining the initial torque of the engine based on the engine speed data and load data includes: Obtain the fourth pre-defined relationship between engine speed, engine load and friction torque, and the fifth pre-defined relationship between engine speed, exhaust and intake pressure difference and pumping loss torque. The friction torque is determined based on the actual engine speed, engine load, and the fourth correspondence; the pumping loss torque is determined based on the actual engine speed, exhaust-intake pressure difference, and the fifth correspondence. The initial torque of the engine is obtained based on the friction torque, the pumping loss torque, and the generator required torque.

11. A vehicle comprising a memory and a controller, the memory storing a computer program executable on the controller, characterized in that, When the controller executes the computer program, it implements the engine control method as described in any one of claims 1 to 10.

Images