A control method of a vehicle, a vehicle, and a storage medium

Abstract

The application provides a control method of a vehicle, the vehicle and a storage medium, and belongs to the technical field of hybrid control. The method comprises the following steps: obtaining a current operating parameter of an engine; determining a pumping pulsation torque generated when the engine is started by a target motor and a target gain coefficient based on the current operating parameter of the engine; determining a target compensation torque of the target motor based on the pumping pulsation torque and the target gain coefficient; and finally controlling the target motor to output the target compensation torque so as to offset the transmission system vibration caused by the pumping pulsation torque. The method can effectively offset the transmission system vibration caused by the pumping pulsation torque, and ensure the driving smoothness and comfort during the engine starting stage.

Description

Technical Field

[0001] This application relates to the field of hybrid power control technology, and more specifically, to a vehicle control method, vehicle, and storage medium in the field of hybrid power control technology. Background Technology

[0002] In a hybrid system, the engine does not perform fuel injection and ignition during the start-up and drag phase. When the electric motor drives the crankshaft, the gas in the cylinder is periodically compressed and expanded, which will produce obvious pumping pulsation torque.

[0003] The pump's pulsating torque may be transmitted to the transmission system through the torsional vibration damper. When the pulsating frequency of the pump's pulsating torque approaches the resonant frequency of the torsional vibration damper, it will cause vibration in the transmission system, affecting driving comfort. Summary of the Invention

[0004] This application provides a vehicle control method, a vehicle, and a storage medium. The method can control the output of a target motor to compensate for the vibration of the transmission system caused by the pumping air pulsation torque, thereby ensuring driving smoothness and comfort during the engine-driven start-up phase.

[0005] In a first aspect, a vehicle control method is provided, applicable to a hybrid vehicle, the vehicle including an engine and a target motor, the method including: acquiring current operating parameters of the engine; determining, based on the current operating parameters of the engine, the pumping pulsation torque and target gain coefficient generated when the engine is started by being driven by the target motor; determining, based on the pumping pulsation torque and target gain coefficient, the target compensation torque of the target motor; and controlling the target motor to output the target compensation torque to counteract the transmission system vibration caused by the pumping pulsation torque.

[0006] The above technical solution acquires the engine's current operating parameters and, based on these parameters, accurately calculates the real-time pumping pulsation torque generated during the engine's start-up process driven by the target motor. By precisely quantifying the amplitude of this pumping pulsation torque, it provides a reliable data foundation and calculation basis for subsequent torque compensation operations. Simultaneously, it adaptively matches the target gain coefficient to the current operating condition based on the engine's current operating parameters, facilitating precise correction of the torque compensation amplitude and strength of the target motor, thus improving compensation adaptability. In calculating the target compensation torque of the target motor, the target motor's torque is determined jointly based on the pumping pulsation torque and the target gain coefficient. The target compensation torque of the engine is corrected by the target gain coefficient to adjust the determined pump pulsation torque, so that the final target compensation torque can accurately match the actual vibration intensity and operating conditions of the current transmission system. This improves the adaptability of torque compensation, avoids overcompensation due to excessive compensation, and avoids insufficient vibration suppression due to insufficient compensation, thus optimizing the vibration suppression effect. Finally, the target motor is controlled to output the target compensation torque in real time to match the operating conditions, thereby offsetting the torsional vibration of the transmission system caused by the periodic fluctuation of the pump pulsation torque. This avoids abnormal noises in the vehicle transmission and jerking caused by transmission system vibration, ensuring the smoothness and comfort of driving the vehicle during the engine-driven start-up phase.

[0007] In conjunction with the first aspect, in some implementations of the first aspect, the target compensation torque of the target motor is determined based on the pumping air pulsation torque and the target gain coefficient, including: determining the feedforward compensation torque of the target motor based on the pumping air pulsation torque and the current speed of the engine; and multiplying the target gain coefficient by the feedforward compensation torque to obtain the target compensation torque.

[0008] Combining the first aspect and the above-mentioned implementation methods, in some implementation methods of the first aspect, the feedforward compensation torque of the target motor is determined based on the pumping pulsation torque and the current speed of the engine, including: determining the target amplitude compensation coefficient and the target phase compensation angle based on the current speed of the engine; updating the pumping pulsation torque based on the target phase compensation angle to obtain the updated pumping pulsation torque; and multiplying the updated pumping pulsation torque by the target amplitude compensation coefficient to obtain the feedforward compensation torque of the target motor.

[0009] The above technical solution matches the target amplitude compensation coefficient and target phase compensation angle based on the current engine speed, and corrects the pumping pulsation torque based on the target amplitude compensation coefficient and target phase compensation angle. This can offset the phase lag and amplitude attenuation caused by the transmission path in advance, so that the determined target motor feedforward compensation torque can accurately match the actual torque disturbance at the motor end. This achieves precise offsetting of the pumping pulsation torque generated by the engine, effectively suppresses transmission torsional vibration, and improves driving comfort.

[0010] Combining the first aspect and the above implementation methods, in some implementation methods of the first aspect, the pumping pulsation torque is updated based on the target phase compensation angle to obtain the updated pumping pulsation torque, including: compensating the current crankshaft angle of the engine based on the target phase compensation angle to obtain the compensated crankshaft angle; and determining the updated pumping pulsation torque based on the compensated crankshaft angle.

[0011] In conjunction with the first aspect and the above implementation methods, in some implementation methods of the first aspect, the current operating parameters include the current engine speed. Based on the current engine operating parameters, determining the target gain coefficient includes: when the current speed is within a preset speed range, determining a first gain coefficient as the target gain coefficient; wherein, the preset speed range is the speed range that causes resonance in the vehicle's transmission system; the first gain coefficient is greater than zero; when the current speed is not within the preset speed range, determining a second gain coefficient as the target gain coefficient; wherein, the second gain coefficient is equal to zero.

[0012] In the above technical solution, when the engine's current speed is within a preset speed range that can cause resonance in the vehicle's transmission system, a first gain coefficient greater than zero is used to adjust the amplitude of the pumping compensation torque, driving the target motor to output the corresponding compensation torque, thereby effectively suppressing transmission system resonance; when the engine's current speed is not within the preset speed range, a second gain coefficient with a value of zero is used to adjust the amplitude of the pumping compensation torque to ensure that the target motor no longer outputs compensation torque, avoiding the target motor from continuously doing ineffective work and reducing energy consumption.

[0013] Combining the first aspect and the above implementation methods, in some implementation methods of the first aspect, the current operating parameters include the current engine speed and the number of engine cylinders. Based on the current engine operating parameters, the target gain coefficient is determined, including: determining the generation frequency of the pump air pulsation torque based on the current engine speed and the number of engine cylinders; obtaining the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper, and determining the target gain coefficient based on the generation frequency of the pump air pulsation torque, the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper.

[0014] The above technical solution calculates the generation frequency of pump pulsation torque in real time based on the engine's current speed and the inherent number of cylinders. Then, it determines the target gain coefficient based on the generation frequency of pump pulsation torque, the inherent resonant frequency of the torsional vibration damper, and the bandwidth adjustment coefficient. This ensures that the compensation force is automatically increased when the generation frequency of pump pulsation torque approaches the resonant frequency of the torsional vibration damper to suppress torsional vibration resonance in the transmission system. At the same time, the compensation force is automatically attenuated when the generation frequency of pump pulsation torque is far from the resonant frequency of the torsional vibration damper. This can reduce the ineffective work of the target motor and reduce power loss while suppressing transmission system vibration, thus balancing driving comfort and energy consumption.

[0015] Combining the first aspect and the above-described implementations, in some implementations of the first aspect, the current operating parameters include the current crankshaft state parameters and the current coolant temperature of the engine. Based on the current operating parameters of the engine, determining the pumping pulsation torque generated when the engine is started by the target motor includes: determining the basic pulsation torque corresponding to the current crankshaft state parameters based on a first preset correspondence; wherein the first preset correspondence is used to characterize the correspondence between the engine's crankshaft state parameters and the basic pulsation torque; determining the target torque correction coefficient corresponding to the current coolant temperature based on a second preset correspondence; wherein the second preset correspondence is used to characterize the correspondence between the engine's coolant temperature and the torque correction coefficient used to correct the basic pulsation torque; and multiplying the basic pulsation torque and the target torque correction coefficient to obtain the pumping pulsation torque.

[0016] The above technical solution, based on the current crankshaft state parameters of the engine, retrieves the basic pulsating torque from the first preset correspondence. It can obtain the periodic fluctuation characteristics of the pumping torque in real time based on the crankshaft angle and speed, thereby accurately determining the corresponding basic pulsating torque. Then, combined with the current coolant temperature of the engine, it matches the corresponding target torque correction coefficient in the second preset correspondence. This fully considers the resistance differences caused by oil viscosity, mechanical friction, and in-cylinder gas state at different coolant temperatures, thereby determining the target torque correction coefficient used to correct the basic pulsating torque. Subsequently, based on the target torque correction coefficient, the basic pulsating torque is corrected to obtain the pumping pulsating torque. This ensures that the determined pumping pulsating torque is closer to the actual resistance value during the engine's starting process, providing a reliable and accurate basis for the subsequent accurate output of compensation torque by the target motor and suppression of transmission system vibration.

[0017] In conjunction with the first aspect and the above-mentioned implementation methods, in some implementation methods of the first aspect, if the vehicle also includes a planetary gear set, the engine is connected to the target motor through the planetary gear set. The planetary gear set includes a sun gear, a planet carrier, and a ring gear. The sun gear is connected to the target motor, the planet carrier is connected to the engine, and the ring gear is connected to the vehicle's power output shaft. Based on the pumping pulsation torque and the target gain coefficient, the target compensation torque of the target motor is determined, including: based on the pumping pulsation torque and the preset ring gear ratio, the equivalent disturbance torque of the target motor is determined; wherein, the preset ring gear ratio is the ratio between the number of teeth on the ring gear and the number of teeth on the sun gear; the target compensation torque is obtained by multiplying the target gain coefficient by the equivalent disturbance torque.

[0018] Secondly, a vehicle control device is provided, applicable to a hybrid vehicle, the vehicle including an engine and a target motor. The device includes: an acquisition module for acquiring current operating parameters of the engine; a first determination module for determining, based on the current operating parameters of the engine, the pumping pulsation torque and target gain coefficient generated when the engine is started by the target motor; a second determination module for determining, based on the pumping pulsation torque and target gain coefficient, the target compensation torque of the target motor; and a control module for controlling the target motor to output the target compensation torque to counteract the transmission system vibration caused by the pumping pulsation torque.

[0019] In conjunction with the second aspect, in some implementations of the second aspect, the second determining module is specifically used to: determine the feedforward compensation torque of the target motor based on the pump pulsation torque and the current speed of the engine; and multiply the target gain coefficient by the feedforward compensation torque to obtain the target compensation torque.

[0020] In conjunction with the second aspect and the above implementation methods, in some implementation methods of the second aspect, the second determining module includes a determining unit, which is specifically used for: determining the target amplitude compensation coefficient and the target phase compensation angle based on the current engine speed; updating the pumping pulsation torque based on the target phase compensation angle to obtain the updated pumping pulsation torque; and multiplying the updated pumping pulsation torque by the target amplitude compensation coefficient to obtain the target motor feedforward compensation torque.

[0021] In conjunction with the second aspect and the above implementation methods, in some implementation methods of the second aspect, the determining unit includes an updating subunit, which is specifically used to: compensate the current crankshaft angle of the engine based on the target phase compensation angle to obtain the compensated crankshaft angle; and determine the updated pumping pulsation torque based on the compensated crankshaft angle.

[0022] In conjunction with the second aspect and the above implementation methods, in some implementation methods of the second aspect, the current operating parameters include the current engine speed, and the first determining module is further specifically used to: determine the first gain coefficient as the target gain coefficient when the current speed is within a preset speed range; wherein, the preset speed range is the speed range that causes resonance in the vehicle's transmission system; the first gain coefficient is greater than zero; and determine the second gain coefficient as the target gain coefficient when the current speed is not within the preset speed range; wherein, the second gain coefficient is equal to zero.

[0023] In conjunction with the second aspect and the above implementation methods, in some implementation methods of the second aspect, the current operating parameters include the current engine speed and the number of engine cylinders. The first determining module is also specifically used to: determine the generation frequency of the pump air pulsation torque based on the current engine speed and the number of engine cylinders; obtain the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper, and determine the target gain coefficient based on the generation frequency of the pump air pulsation torque, the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper.

[0024] In conjunction with the second aspect and the above implementation methods, in some implementation methods of the second aspect, the current operating parameters include the current crankshaft state parameters and the current coolant temperature of the engine. The first determining module is further specifically used for: determining the basic pulsating torque corresponding to the current crankshaft state parameters based on a first preset correspondence; wherein the first preset correspondence is used to characterize the correspondence between the engine crankshaft state parameters and the basic pulsating torque; determining the target torque correction coefficient corresponding to the current coolant temperature based on a second preset correspondence; wherein the second preset correspondence is used to characterize the correspondence between the engine coolant temperature and the torque correction coefficient used to correct the basic pulsating torque; and multiplying the basic pulsating torque and the target torque correction coefficient to obtain the pumping pulsating torque.

[0025] In conjunction with the second aspect and the above implementation methods, in some implementation methods of the second aspect, if the vehicle also includes a planetary gear set, the engine is connected to the target motor through the planetary gear set. The planetary gear set includes a sun gear, a planet carrier, and a ring gear. The sun gear is connected to the target motor, the planet carrier is connected to the engine, and the ring gear is connected to the vehicle's power output shaft. The second determining module is also specifically used to: determine the equivalent disturbance torque of the target motor based on the pumping pulsation torque and the preset ring gear ratio; wherein, the preset ring gear ratio is the ratio between the number of teeth on the ring gear and the number of teeth on the sun gear; and multiply the target gain coefficient by the equivalent disturbance torque to obtain the target compensation torque.

[0026] Thirdly, a vehicle is provided, including a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, causing the vehicle to perform the vehicle control methods of the first aspect and any possible implementation thereof.

[0027] Fourthly, a computer program product is provided, comprising: computer program code, which, when run on a computer, causes the computer to execute the vehicle control method of the first aspect and any possible implementation thereof.

[0028] Fifthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the vehicle control method of the first aspect and any possible implementation thereof. Attached Figure Description

[0029] Figure 1 This is a schematic flowchart of a vehicle control method provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a hybrid vehicle provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a vehicle control device provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application. Detailed Implementation

[0030] The technical solutions in this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.

[0031] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0032] In hybrid vehicles, during the process of starting the engine by driving the electric motor, before the engine has performed fuel injection and ignition, the gas inside the engine cylinders is periodically compressed and expanded when the electric motor drives the crankshaft, which will produce obvious pumping pulsating torque.

[0033] Although the torsional vibration damper can attenuate the pumping pulsation torque to some extent, some of the pumping pulsation torque will still be transmitted to the transmission system through the torsional vibration damper. Furthermore, when the pulsation frequency of the pumping pulsation torque is close to the natural resonant frequency of the torsional vibration damper, it is easy to cause resonance in the transmission system and further induce vibration of the vehicle floor, thereby reducing the ride comfort of the vehicle.

[0034] To address the aforementioned technical problems, this application provides a vehicle control method. The method is executed by the vehicle, specifically a controller within the vehicle. Based on the pump pulsating torque and the target gain coefficient, the method accurately determines a target compensation torque suitable for the current operating conditions. Then, it controls the target motor to output this target compensation torque, thereby counteracting the transmission system vibration caused by the pump pulsating torque and ensuring smooth and comfortable driving during engine-driven start-up.

[0035] Figure 1 This is a schematic flowchart of a vehicle control method provided in an embodiment of this application.

[0036] For example, the method is applied to a hybrid vehicle, specifically to a hybrid control unit (HCU) in the hybrid vehicle, which may include a target motor and an engine; like Figure 1 As shown, the method 100 includes: Step 101: Obtain the current operating parameters of the engine.

[0037] Step 102: Based on the engine's current operating parameters, determine the pumping pulsation torque and target gain coefficient generated when the engine is towed to start.

[0038] Step 103: Determine the target compensation torque of the target motor based on the pump air pulsation torque and the target gain coefficient.

[0039] Step 104: Control the target motor to output the target compensation torque to counteract the vibration of the transmission system caused by the pump air pulsation torque.

[0040] In this embodiment, the current operating parameters of the engine are obtained, and based on these parameters, the real-time pumping pulsation torque generated during the engine's start-up process driven by the target motor is accurately calculated. By precisely quantifying the amplitude of the pumping pulsation torque, a reliable data foundation and calculation basis are provided for subsequent torque compensation operations. Simultaneously, a target gain coefficient is adaptively matched to the current operating conditions based on the engine's current operating parameters, facilitating precise correction of the torque compensation amplitude and strength of the target motor, thus improving compensation adaptability. During the calculation of the target compensation torque of the target motor, the target is determined jointly based on the pumping pulsation torque and the target gain coefficient. The target compensation torque of the motor is corrected by the target gain coefficient to adjust the determined pumping pulsation torque, so that the final target compensation torque can accurately match the actual vibration intensity and operating conditions of the current transmission system. This improves the adaptability of torque compensation, avoids overcompensation due to excessive compensation, and avoids insufficient vibration suppression due to insufficient compensation, thus optimizing the vibration suppression effect. Finally, the target motor is controlled to output the target compensation torque in real time to match the operating conditions, thereby offsetting the torsional vibration of the transmission system caused by the periodic fluctuation of the pumping pulsation torque. This avoids abnormal noises in the vehicle transmission and jerking caused by transmission system vibration, ensuring the smoothness and comfort of driving the vehicle during the engine-driven start-up phase.

[0041] The following is about Figure 1 The specific implementation methods of each step in the illustrated embodiment are explained below: In step 101, the aforementioned current operating parameters refer to parameters that can reflect the operating status of the engine-driven start-up phase in real time.

[0042] For example, the aforementioned current operating parameters may include, but are not limited to: engine speed, engine crankshaft angle, engine coolant temperature, and number of cylinders.

[0043] The engine speed mentioned above is used to characterize the number of revolutions per minute of the engine crankshaft, which can intuitively reflect the speed at which the engine is driven by the target motor. The unit is revolutions per minute (r / min or rpm). The crankshaft pulse signal is usually collected in real time by the engine crankshaft position sensor, and then the engine controller processes the crankshaft pulse signal to obtain the real-time engine speed.

[0044] The crankshaft angle of the engine mentioned above refers to the real-time angular position of the engine crankshaft relative to the top dead center reference position, and the unit is crankshaft angle (°CA). It is usually obtained by the crankshaft position sensor and the camshaft position sensor working together to collect pulse signals and phase signals. Then, the engine controller calculates the real-time crankshaft angle of the engine based on the reference missing tooth signal, pulse signal and phase signal in real time.

[0045] The engine water temperature mentioned above refers to the real-time temperature of the engine coolant, used to characterize the overall hot and cold state of the engine, and is measured in °C (degrees Celsius). It is usually collected by a voltage analog signal from a temperature sensor located in the engine block or thermostat (a coolant temperature control valve component installed between the engine cylinder head outlet and the radiator inlet). The engine controller then performs digital-to-analog conversion on the voltage analog signal to obtain the actual engine water temperature.

[0046] The number of cylinders in the engine mentioned above refers to the inherent physical total number of cylinders in the engine, in units of one. Usually, the fixed total number of cylinders of the engine can be pre-written by the HCU according to the engine model, and can be directly called and read during operation without the need for real-time data collection.

[0047] Furthermore, after obtaining the current operating parameters of the engine, the pumping pulsation torque generated when the engine is driven to start by the target motor can be determined based on the current operating parameters of the engine. At the same time, the target gain coefficient used to adjust the compensation level of the target motor can also be determined based on the current operating parameters of the engine.

[0048] In step 102, as mentioned above, the target motor refers to the motor in the vehicle that drives the engine to start; The aforementioned pump pulsation torque refers to the alternating intake and exhaust resistance formed by the periodic intake and exhaust of each cylinder during the engine start-up process driven by the target motor, which in turn generates a periodically fluctuating resistance torque on the crankshaft.

[0049] Since the pulsating torque from the pumped air may be transmitted to the transmission system via the torsional vibration damper, and when the pulsating frequency of the pumped air torque is close to the natural resonant frequency of the torsional vibration damper, it can easily cause resonance in the transmission system, resulting in poor ride comfort. Based on this, the embodiments of this application can control the target motor to output a corresponding compensating torque to counteract the transmission system vibration caused by the pulsating torque from the pumped air.

[0050] In order to accurately control the output compensation torque of the target motor, the specific value of the pump air pulsation torque can be accurately determined first, and this can be used as the basic input for torque compensation calculation.

[0051] Because the amplitude of the pumping pulsating torque fluctuates significantly and its vibration frequency changes dynamically with the engine speed in real time, and because the pumping pulsating torque itself is affected by various parameters such as phase, speed, and water temperature, the computational load for real-time iterative calculation is extremely large, easily leading to response lag and making it difficult to meet the real-time compensation requirements of the target motor. Therefore, this embodiment of the application can pre-build the correspondence between the engine's operating parameters and the pumping pulsating torque, and store this correspondence in the vehicle's storage module; after obtaining the engine's current operating parameters, the pumping pulsating torque corresponding to the current operating parameters can be determined based on this correspondence.

[0052] Optionally, the correspondence between the engine's operating parameters and the pumping pulsation torque can be the correspondence between the engine's crankshaft angle, engine speed, and coolant temperature and the pumping pulsation torque. After obtaining the engine's current crankshaft angle, current engine speed, and current coolant temperature, the pumping pulsation torque corresponding to these three parameters can be determined from this correspondence.

[0053] For example, the correspondence between the engine's operating parameters and the pump pulsation torque can also include two sets of correspondences, namely a first preset correspondence and a second preset correspondence; wherein, the first preset correspondence is used to characterize the correspondence between the engine's crankshaft state parameters and the basic pulsation torque; and the second preset correspondence is used to characterize the correspondence between the engine's coolant temperature and the torque correction coefficient used to correct the basic pulsation torque.

[0054] In some embodiments, the current operating parameters include the current crankshaft state parameters and the current coolant temperature of the engine. Based on the current operating parameters of the engine, determining the pumping pulsation torque generated when the engine is started by the target motor includes: determining the basic pulsation torque corresponding to the current crankshaft state parameters based on a first preset correspondence; wherein the first preset correspondence is used to characterize the correspondence between the engine's crankshaft state parameters and the basic pulsation torque; determining the target torque correction coefficient corresponding to the current coolant temperature based on a second preset correspondence; wherein the second preset correspondence is used to characterize the correspondence between the engine's coolant temperature and the torque correction coefficient used to correct the basic pulsation torque; and multiplying the basic pulsation torque and the target torque correction coefficient to obtain the pumping pulsation torque.

[0055] The current crankshaft state parameters of the aforementioned engine refer to the operating state parameters used to characterize the real-time rotational state and angular position of the crankshaft.

[0056] For example, the aforementioned current crankshaft state parameters may include the engine's current crankshaft angle and the engine's current speed.

[0057] Furthermore, as mentioned above, a bench calibration experiment can be conducted to adjust the crankshaft state parameters of the engine at a fixed engine coolant temperature to obtain the actual measured basic pulsating torque data under different crankshaft state parameters. Then, the obtained basic pulsating torque data is fitted and interpolated to generate a first preset correspondence between the crankshaft state parameters and the basic pulsating torque. At the same time, the engine coolant temperature can be adjusted at a fixed crankshaft state parameter to obtain the pump pulsating torque at different coolant temperatures. Based on this, the influence law of engine coolant temperature on pump pulsating torque can be deduced, thereby fitting a second preset correspondence between engine coolant temperature and torque correction coefficient. After completing the calibration of the above two sets of correspondences, the constructed first and second preset correspondences can be stored in the vehicle's storage module for real-time retrieval during vehicle operation.

[0058] It is understandable that, due to the different engine models, their corresponding stroke structures and variable cylinder configurations are also different, resulting in different fluctuation characteristics of pumping pulsation torque under the same crankshaft state parameters. Therefore, different first preset correspondences can be constructed for different engine models. Similarly, due to the different engine models, their overall displacement, cylinder structure, intake and exhaust resistance characteristics, and friction loss characteristics are all different, resulting in inconsistent torque correction ranges at the same water temperature. Therefore, different second preset correspondences can be constructed for different engine models.

[0059] In some embodiments, a first preset correspondence and a second preset correspondence corresponding to the engine model can be stored in the vehicle's storage module according to the engine model of the vehicle.

[0060] For example, taking an inline four-cylinder engine (also known as an "L4 engine," an internal combustion engine structure in which four cylinders are arranged in a straight line side by side) as an example, the first preset correspondence between the constructed crankshaft state parameters and the basic pulsating torque can be shown in Table 1 below: Table 1

[0061] In Table 1 above, X refers to the engine speed in rpm; Y refers to the engine crankshaft angle in degrees. Based on the engine speed and crankshaft angle, the corresponding basic pulsating torque can be looked up in Nm.

[0062] It should be understood that Table 1 above can be obtained by adjusting the crankshaft state parameters of the engine under the condition that the engine coolant temperature is 90°C. Table 1 above is only an example of the first preset correspondence, and the first preset correspondence can also be obtained experimentally under other coolant temperature conditions; in addition to the correspondence shown in Table 1, the first preset correspondence can also include the correspondence between other crankshaft state parameters and basic pulsating torque, and this application embodiment does not limit this.

[0063] Understandably, since this is an L4 engine, as shown in Table 1, within one working cycle (i.e., crankshaft angle from 0° to 720°), four similar torque waveforms are visually visible, each corresponding to one of the four cylinders of the L4 engine. It should be understood that the number of similar torque waveforms will differ depending on the engine model. For example, a three-cylinder engine will exhibit three sets of pulsating torque waveforms corresponding to each cylinder within a complete working cycle, while a six-cylinder engine will produce six sets of torque waveforms corresponding to each cylinder.

[0064] Taking an engine speed of 800 rpm as an example, at 270° (near the top dead center of a cylinder's compression), the torque reaches a positive peak of 45 Nm, which manifests as huge resistance; while at 90° (near the bottom dead center of a cylinder's expansion), the torque is -15 Nm, which manifests as a push-back assist; 0°, 360° and 720° are the top dead center of the scavenging, and the torque is zero.

[0065] As can be seen, when the crankshaft reaches the top dead center of the compression stroke, the piston moves upward and compresses the air in the cylinder. The gas pressure creates a strong resistance to the crankshaft rotation, and the corresponding basic pulsating torque shows a positive peak value. When the crankshaft reaches the bottom dead center of the expansion stroke, the residual high-pressure gas in the cylinder pushes the piston downward, which in turn drives the crankshaft to rotate. The corresponding basic pulsating torque is negative, creating a boosting effect. At the top dead center of the scavenging stroke, the piston completes the reversal of the intake and exhaust strokes. The forces of the gas in the cylinder cancel each other out, and the pumping effect generated by the intake and exhaust is the weakest, with the basic pulsating torque approaching zero.

[0066] When the crankshaft angle of the engine is 270°, as the engine speed increases from 800 rpm to 1100 rpm (close to the resonance frequency of the torsional vibration damper), the peak torque increases from 45 Nm to 52 Nm, reflecting the increased intensity of pulsation excitation. As the engine speed continues to rise to 1500 rpm, the intensity of pulsation excitation weakens.

[0067] It is evident that, for the same crankshaft angle, as the rotational speed gradually increases, the intake and exhaust airflow speeds of the cylinder accelerate, the throttling loss and gas compression loss increase simultaneously, and the excitation intensity of the pump pulsation increases accordingly. When the rotational speed approaches the inherent resonant frequency of the torsional vibration damper, the transmission system generates a resonance effect, further amplifying the amplitude of the basic pulsating torque. When the rotational speed continues to increase and exceeds the resonant frequency range, the resonance amplification effect disappears, and the overall pulsating excitation intensity decreases accordingly.

[0068] Furthermore, taking an inline four-cylinder engine (also known as an "L4 engine," an internal combustion engine structure with four cylinders arranged in a straight line) as an example, the established correspondence between the engine's coolant temperature and the first preset torque correction coefficient used to correct the basic pulsating torque can be shown in Table 2 below: Table 2

[0069] In Table 2 above, T refers to the engine coolant temperature, in °C; f T This refers to the torque correction factor used to correct the basic pulsating torque.

[0070] It should be understood that Table 2 above is only an example of the second preset correspondence; in addition to the correspondence shown in Table 2, the second preset correspondence may also include other correspondences between water temperature and torque correction coefficients, and this application embodiment does not limit this.

[0071] Understandably, as shown in Table 2, when the engine coolant temperature is 90℃, the correction factor is 1, which is equivalent to directly outputting the basic pulsating torque. However, at low temperatures (e.g., -20℃), due to the extremely high viscosity of the engine oil, the pumping resistance increases significantly, and the pumping pulsating torque at the same engine speed and crankshaft angle is 1.5 times the basic pulsating torque. In other words, as the engine coolant temperature decreases, the torque correction factor in Table 2 tends to increase.

[0072] It is evident that engine coolant temperature alters overall engine friction loss and the state of gas within the cylinder, thus affecting the actual value of the pumping pulsation torque. Specifically, the lower the coolant temperature, the higher the oil viscosity, resulting in a significant increase in the mechanical friction resistance of the piston and crankshaft. Simultaneously, the higher air density within the cylinder at low temperatures leads to greater compression resistance, resulting in a significantly larger overall pumping resistance compared to the baseline operating conditions at normal temperature, with a corresponding torque correction factor greater than 1. As the coolant temperature gradually increases, the oil viscosity continuously decreases, and friction loss gradually declines, with the corresponding torque correction factor approaching 1.

[0073] Furthermore, after obtaining the basic pulsating torque and the target torque correction coefficient, the basic pulsating torque and the target torque correction coefficient can be multiplied to obtain the pumping pulsating torque.

[0074] For example, assuming that Tables 1 and 2 above have been stored in the vehicle's storage module in advance, if the current engine speed is 800 rpm, the current crankshaft angle is 270°, and the current coolant temperature is 25°, then based on the current engine speed of 800 rpm and the current crankshaft angle of 270°, the corresponding basic pulsating torque of 45 Nm can be obtained from Table 1. Based on the current coolant temperature of 25°, the corresponding target torque correction coefficient of 1.10 can be obtained from Table 2. Then, the basic pulsating torque and the target torque correction coefficient are multiplied together to obtain the pump pulsating torque of 45 * 1.10 = 49.5 Nm.

[0075] The above method, based on the current crankshaft state parameters of the engine, retrieves the basic pulsating torque from the first preset correspondence. It can obtain the periodic fluctuation characteristics of the pumping torque in real time based on the crankshaft angle and speed, thereby accurately determining the corresponding basic pulsating torque. Then, combined with the current coolant temperature of the engine, it matches the corresponding target torque correction coefficient in the second preset correspondence. This fully considers the resistance differences caused by oil viscosity, mechanical friction, and in-cylinder gas state at different coolant temperatures, thereby determining the target torque correction coefficient used to correct the basic pulsating torque. Subsequently, based on the target torque correction coefficient, the basic pulsating torque is corrected to obtain the pumping pulsating torque. This ensures that the determined pumping pulsating torque is closer to the actual resistance value during the engine's start-up process, providing a reliable and accurate basis for the subsequent accurate output of compensation torque by the target motor and suppression of transmission system vibration.

[0076] Furthermore, the aforementioned target gain coefficient is used to adaptively adjust the compensation torque output by the target motor, and is a correction coefficient for adjusting the degree of compensation of the compensation torque output by the target motor.

[0077] As mentioned above, since the resonance phenomenon of the transmission system will only be triggered when the frequency of the pump air pulsation torque is close to the natural resonant frequency of the torsional vibration damper, in order to avoid unnecessary power loss caused by the target motor continuously outputting compensation torque when the transmission system is not in the resonance range, the above-mentioned target gain coefficient can be adaptively matched and set in combination with the resonant speed range corresponding to the torsional vibration damper.

[0078] For example, the target gain coefficient can be determined based on the engine's current speed to determine whether the current pumping pulsation torque will cause the torsional vibration damper to resonate.

[0079] In some embodiments, the current operating parameters include the current engine speed. Based on the current engine operating parameters, determining the target gain coefficient includes: when the current speed is within a preset speed range, determining a first gain coefficient as the target gain coefficient; wherein the preset speed range is the speed range that causes resonance in the vehicle's transmission system; the first gain coefficient is greater than zero; when the current speed is not within the preset speed range, determining a second gain coefficient as the target gain coefficient; wherein the second gain coefficient is equal to zero.

[0080] The aforementioned preset speed range refers to the speed range in which the excitation frequency of the pump's pulsating torque exactly matches the natural frequency of the torsional vibration damper, and can cause resonance in the vehicle's transmission system.

[0081] For example, the preset speed range can be set according to the inherent characteristics of the torsional vibration damper and in conjunction with the torsional vibration calibration test of the whole machine bench. For instance, if the pumping pulsation torque of the engine causes the torsional vibration damper to resonate when the engine speed is in the range of [800rpm, 1500rpm], then the preset speed range can be set to [800rpm, 1500rpm].

[0082] Furthermore, if the current engine speed is within the preset speed range, it indicates that the pumping pulsation torque of the engine may cause the torsional vibration damper to resonate. The target motor needs to output a corresponding compensation torque to suppress the vibration of the transmission system. Therefore, the first gain coefficient, which is greater than zero, can be determined as the target gain coefficient. This ensures that the target motor can output a certain compensation torque to suppress the vibration of the transmission system when the compensation torque of the target motor is corrected by the first gain coefficient. If the engine's current speed is not within the preset speed range, it means that the pumping pulsation torque of the engine will not cause the torsional vibration damper to resonate. There is no need for the target motor to output the corresponding compensation torque, thus avoiding unnecessary torque compensation. Therefore, the second gain coefficient, which is equal to zero, can be determined as the target gain coefficient. This ensures that the target motor does not need to output compensation torque when the compensation torque of the target motor is corrected through the second gain coefficient, thereby avoiding unnecessary power loss.

[0083] For example, the first gain coefficient can be set according to actual needs. For instance, it can be dynamically adjusted adaptively based on the state parameters of the torsional vibration damper, the peak value of the pump pulsating torque, the engine water temperature, and the real-time engine speed, as long as the first gain coefficient is limited to be greater than zero.

[0084] Furthermore, assuming the preset speed range is [800rpm, 1500rpm], the first gain coefficient is set to 0.8, and the second gain coefficient is set to 0. If the current engine speed is 900rpm, and it is determined that the current engine speed is within the preset speed range, then 0.8 can be determined as the target gain coefficient; if the current engine speed is 200rpm, then 0 can be determined as the target gain coefficient.

[0085] Optionally, to avoid a sudden jump in the target gain coefficient, which could lead to a sudden change in the target motor compensation torque and introduce additional shock and vibration, this embodiment of the application may further add speed transition intervals at both ends of the original preset speed range. When the engine speed increases from low to enter the speed transition interval before the preset speed range, the target gain coefficient increases smoothly and linearly from zero to the first gain coefficient as the speed increases. When the engine speed is stable within the preset speed range, the target gain coefficient remains unchanged at the first gain coefficient. When the engine speed increases to enter the speed transition interval after the preset speed range, the target gain coefficient decreases smoothly and linearly from the first gain coefficient to the second gain coefficient.

[0086] For example, assuming the preset speed range is [800rpm, 1500rpm], the width of the transition range before and after is uniformly set to 50rpm, the first gain coefficient is set to 0.8, and the second gain coefficient is set to 0; when the engine speed increases from low to enter the first speed transition range of [750rpm, 800rpm], the target gain coefficient increases smoothly and linearly from zero to the first gain coefficient, i.e., 0.8; when the engine speed is stable in the preset speed range of [800rpm, 1500rpm], the target gain coefficient remains unchanged at 0.8; when the engine speed increases to enter the second speed transition range of [1500rpm, 1550rpm], the target gain coefficient decreases smoothly and linearly from the first gain coefficient, i.e., 0.8, to the second gain coefficient, which is zero; when the speed is below 750rpm or above 1550rpm, the target gain coefficient remains the second gain coefficient, which is zero.

[0087] The above method involves adjusting the amplitude of the pumping compensation torque using a first gain coefficient greater than zero when the engine's current speed is within a preset speed range that could cause resonance in the vehicle's transmission system. This drives the target motor to output the corresponding compensation torque, thereby effectively suppressing transmission system resonance. When the engine's current speed is not within the preset speed range, adjusting the amplitude of the pumping compensation torque using a second gain coefficient of zero ensures that the target motor no longer outputs compensation torque, preventing the target motor from continuously performing ineffective work and reducing energy consumption.

[0088] To more accurately control the compensation torque output of the target motor, the target gain coefficient can be dynamically determined based on the engine's current operating parameters and the actual characteristics of the torsional vibration damper.

[0089] In other embodiments, the current operating parameters include the current engine speed and the number of engine cylinders. Based on the current engine operating parameters, the target gain coefficient is determined, including: determining the generation frequency of the pump pulsation torque based on the current engine speed and the number of engine cylinders; obtaining the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper; and determining the target gain coefficient based on the generation frequency of the pump pulsation torque, the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper.

[0090] The resonant frequency of the aforementioned torsional vibration damper refers to the inherent vibration frequency of the damper itself. When the frequency of the pump's pulsating torque is close to the resonant frequency of the damper, torsional resonance will occur in the transmission system, significantly amplifying the vibration amplitude. The resonant frequency of the damper can usually be obtained by directly reading the factory calibration parameters of the damper components stored in the vehicle.

[0091] The bandwidth adjustment coefficient mentioned above is used to adjust the steepness of the resonance peak of the gain curve. It is also called the quality factor and its value ranges from 2 to 5. It can usually be set according to actual needs. For example, if the actual need is to compensate when the generation frequency of the pump air pulsation torque is extremely close to the resonance frequency of the torsional vibration damper, a larger value can be taken; if the actual need is to intervene in compensation in advance when the generation frequency of the pump air pulsation torque is not yet completely close to the resonance frequency of the torsional vibration damper, a smaller value can be taken.

[0092] Understandably, the larger the bandwidth adjustment coefficient, the steeper the resonance peak of the gain curve. Only when the frequency of the pumping air pulsation torque is very close to the resonance frequency of the torsional vibration damper will the compensation gain increase significantly and the compensation force be significantly enhanced. Once it deviates from this narrow frequency range, the compensation force will decrease rapidly. The smaller the bandwidth adjustment coefficient, the wider the effective vibration reduction frequency bandwidth. Even if the frequency of the pumping air pulsation torque has not yet fully coincided with the resonance frequency of the torsional vibration damper, compensation can be intervened in advance.

[0093] Furthermore, the frequency of pump pulsation torque generation can typically be determined based on the engine's current speed and the number of cylinders.

[0094] For example, the crankshaft completes one working cycle in 2 revolutions (720°). Taking a 4-cylinder engine with 4 compression strokes in one working cycle (720°) as an example, each stroke produces one pulsation, that is, 4 pulsations are produced in one working cycle. This means that the number of pulsations corresponding to each revolution of the crankshaft is 4 / 2 = 2 times. That is, the number of pulsations corresponding to each revolution of the crankshaft is half of the number of cylinders in the engine (i.e., the number of cylinders in the engine).

[0095] Let n be the number of pulsations per revolution of the crankshaft, and let n be the engine speed. The number of times the pump pulsation torque is generated per minute is *n converts the number of pulses per minute to the number of pulses per second. *n / 60, from which the calculation formula for the generation frequency of pump air pulsation torque is derived as shown in the following formula (1): Formula (1) In the above formula (1), This refers to the frequency at which the pump's air pulsation torque is generated, and the unit is Hertz (Hz). This refers to the number of pulses per revolution of the crankshaft, which is usually equal to half the number of cylinders in the engine. This refers to the current engine speed, which can be obtained by referring to the method described above.

[0096] For example, assuming the current engine speed is 300 rpm and the engine has 4 cylinders, the number of pulsations per crankshaft revolution is determined to be 2, i.e., n equals 2. Then, n=2 and... Substituting 300rpm into the above formula (1), we can calculate that the frequency of the pump air pulsation torque is 100Hz.

[0097] It is understandable that in a transmission system, the frequency of the pumping air pulsation torque is the external excitation frequency that induces torsional vibration. When the frequency of the pumping air pulsation torque approaches the natural resonant frequency of the torsional vibration damper, resonance is easily triggered. Therefore, embodiments of this application can introduce bandpass characteristic calculation logic to jointly calculate the target gain coefficient based on the real-time calculated frequency of the pumping air pulsation torque, the fixed resonant frequency of the torsional vibration damper, and the bandwidth adjustment coefficient used to adjust the width of the damping range.

[0098] For example, the target gain coefficient mentioned above can be calculated using the following formula (2): Formula (2) In the above formula (2), K refers to the target gain coefficient; This refers to the frequency at which the pump's air pulsation torque is generated, measured in Hertz (Hz); Q refers to the bandwidth adjustment factor (i.e., the quality factor). This refers to the resonant frequency of the torsional vibration damper, measured in Hertz (Hz).

[0099] It is understandable that, according to the above formula (2), when the frequency of pump air pulsation torque generation... The closer to the resonant frequency of the torsional vibration damper When the target gain coefficient K approaches 1, the frequency of pump pulsation torque generation increases. The further away from the resonant frequency of the torsional vibration damper As the denominator increases, the target gain coefficient K decays rapidly and approaches 0.

[0100] For example, assuming the resonant frequency of the torsional vibration damper is 30Hz and the bandwidth adjustment coefficient is currently set to 3, if the calculated frequency of the pump air pulsation torque is 30Hz, then by substituting the pump air pulsation torque generation frequency, the resonant frequency of the torsional vibration damper, and the bandwidth adjustment coefficient into the above formula (2), the target gain coefficient can be calculated to be 1; and if the calculated frequency of the pump air pulsation torque generation frequency is 20Hz, then by substituting the pump air pulsation torque generation frequency, the resonant frequency of the torsional vibration damper, and the bandwidth adjustment coefficient into the above formula (2), the target gain coefficient can be calculated to be 0.138.

[0101] It can be seen that when the frequency of the pump air pulsation torque is close to the resonant frequency of the torsional vibration damper, the target gain coefficient is usually close to 1; while when the frequency of the pump air pulsation torque is far from the resonant frequency of the torsional vibration damper, the target gain coefficient is usually close to 0.

[0102] The above method calculates the generation frequency of pump pulsation torque in real time based on the engine's current speed and the inherent number of cylinders. Then, it determines the target gain coefficient based on the generation frequency of pump pulsation torque, the inherent resonant frequency of the torsional vibration damper, and the bandwidth adjustment coefficient. This ensures that the compensation force is automatically increased when the generation frequency of pump pulsation torque approaches the resonant frequency of the torsional vibration damper to suppress torsional vibration resonance in the transmission system. At the same time, the compensation force is automatically attenuated when the generation frequency of pump pulsation torque is far from the resonant frequency of the torsional vibration damper. This can suppress transmission system vibration while reducing the ineffective work of the target motor, reducing power loss, and balancing driving comfort and energy consumption.

[0103] Furthermore, after obtaining the pump pulsation torque and target gain coefficient, the target compensation torque of the target motor can be determined together based on the pump pulsation torque and target gain coefficient.

[0104] In steps 103 and 104, the target compensation torque of the target motor is used to counteract the vibration of the transmission system caused by the pump air pulsation torque.

[0105] In some embodiments, when the target motor and the engine are mechanically coupled and rigidly connected, the pump pulsation torque can be directly multiplied by the target gain coefficient and the negative value can be used as the target compensation torque of the target motor. This can counteract the torque disturbance caused by the pump pulsation torque, thereby suppressing the vibration of the transmission system.

[0106] For example, assuming the target compensation torque of the target motor is defined as T1, the target gain coefficient is defined as K, and the pump pulsation torque is defined as T2, then T1 = -K * T2.

[0107] Understandably, due to the mechanical coupling and rigid connection between the engine and the target motor, their speeds are always synchronized. Any torque fluctuation on the drive shaft will act simultaneously on both the engine and motor ends. When the engine generates periodic pumping pulsation torque during the engine's start-up process, the target motor, which is coaxially arranged with the engine, can be controlled to quickly output compensating torque. By applying compensating torque with opposite phase and matching amplitude, the torque fluctuation caused by the pumping pulsation torque can be directly offset and counteracted on the coaxial axis, thereby suppressing transmission system vibration.

[0108] In other embodiments, if the vehicle includes a planetary gear set and the engine is connected to the target motor through the planetary gear set, the target compensation torque of the target motor can be determined by combining the torque balance relationship of the planetary gear set and the pump pulsation torque and the target gain coefficient.

[0109] For example, a vehicle including a planetary gear structure can be as follows: Figure 2 As shown, a hybrid vehicle may include: a first motor 201, a planetary gear set 202, and a first clutch (i.e., Figure 1 S1) 203, engine 204, second motor 205, second clutch (i.e. Figure 1 S2)206, differential 207 and torsional vibration damper 208.

[0110] The first motor 201, also called the GM motor (Generator Motor), is the "target motor" mentioned earlier. The first motor is connected to the engine 204 via the planetary gear set 202 and can be used to start the engine or driven by the engine to function as a generator. In some cases, the first motor 201 can also act as a drive motor, assisting the engine 204 in outputting power to drive the vehicle.

[0111] The planetary gear set 202 includes a planet carrier 2021, a sun gear 2022, and a ring gear 2023. Specifically, a first motor 201 is connected to the sun gear 2022 of the planetary gear set 202, and a second motor 205 is connected to the ring gear 2023. The ring gear 2023 can also be connected to the vehicle's output shaft to ensure that the output power of the ring gear 2023 is used to drive the vehicle's wheels. An engine 204 is connected to the planet carrier 2021 of the planetary gear set 202. The ring gear 2023 of the planetary gear set 202 is connected to the differential 207 and is used to output power to drive the vehicle.

[0112] The first clutch (S1) 203 is connected to the planetary gear set 202. Specifically, one side of the first clutch (S1) 203 is connected to the planet carrier 2021, and the other side can be selectively connected to the ring gear 2023 or the sun gear 2022. If one side of the first clutch 203 is connected to the planet carrier 2021 and the other side is connected to the ring gear 2023, then... Figure 1 As shown, closing the first clutch 203 will lock the ring gear 2023 to the planetary carrier 2021; conversely, if one side of the first clutch 203 is connected to the planetary carrier 2021 and the other side is connected to the sun gear 2022, closing the first clutch 203 will lock the sun gear 2022 to the planetary carrier 2021. In summary, regardless of whether the other side of the first clutch 203 is connected to the ring gear 2023 or the sun gear 2022, when the first clutch 203 is closed, the planetary gear set 202 will be locked as a whole due to the locking of the two components. At this time, all the power of the engine 204 is transmitted to the ring gear 2023. When the first clutch 203 is open, the power output by the engine 204 is transmitted through the planetary carrier 2021, partly to the first motor 201 and partly to the ring gear 2023.

[0113] The second motor 205, also called the TM motor (Traction Motor), is connected to the differential 207 via the second clutch 206 and is used to output power to the differential 207 to drive the vehicle.

[0114] The second clutch 206 is used to disconnect or connect the mechanical connection between the second motor 205 and the differential 207. Specifically, when the second clutch 206 is in the closed state, the second motor 205 and the differential 207 are mechanically connected, and the second motor 205 can output power to drive the vehicle. When the second clutch 206 is in the open state, the second motor 205 and the differential 207 are disconnected.

[0115] The differential 207 is used to allow the left and right wheels to rotate at different speeds when the vehicle is turning. With the differential 207, the outer wheel can rotate at a faster speed, and the inner wheel can rotate at a slower speed, ensuring smooth cornering of the vehicle.

[0116] The torsional vibration damper 208 is located between the engine 204 and the planetary gear set 202. Specifically, it is used to buffer the impact during power transmission, absorb the instantaneous torque fluctuations of the engine output, attenuate the torsional vibration transmitted from the engine's pumping pulsating torque to the planetary gear set and the motor end, and reduce the vibration disturbance caused by gear meshing and the operation of rotating parts.

[0117] Furthermore, in such Figure 2 In the hybrid vehicle shown, the planetary gear set includes a sun gear, a planet carrier, and a ring gear. The sun gear is connected to the first motor (i.e., the "target motor" mentioned above), the planet carrier is connected to the engine, and the ring gear is connected to the vehicle's power output shaft. The torque balance relationship of this planetary gear set structure is shown in the following formula (3): Formula (3) In the above formula (3), This refers to the output torque (also known as the torque of the sun gear) of the first motor (i.e., the "target motor" mentioned above). This refers to the torque of the gear ring (which is usually applied to the wheel end). This refers to the engine's output torque (i.e., the torque of the planetary carrier). It refers to the ratio between the number of teeth on the ring gear and the number of teeth on the sun gear, and is a characteristic coefficient of the planetary gear set.

[0118] In some embodiments, determining the target compensation torque of the target motor based on the pump air pulsation torque and the target gain coefficient includes: determining the equivalent disturbance torque of the target motor based on the pump air pulsation torque and the preset gear ratio; wherein the preset gear ratio is the ratio between the number of teeth on the gear ring and the number of teeth on the sun gear; and multiplying the target gain coefficient by the equivalent disturbance torque to obtain the target compensation torque.

[0119] It is understandable that the pumping pulsation torque generated by the engine (which can correspond to the torque in formula (3)) The pump's pulsating torque is directly applied to the planetary carrier. Constrained by the planetary gear torque distribution relationship, it will be coupled and transmitted to the sun gear side according to a fixed transmission ratio, forming the equivalent disturbance torque corresponding to the first motor (i.e., the "target motor" mentioned above). (This can correspond to the torque in formula (3)) ).

[0120] For example, by transforming the above formula (3), the calculation formula for the equivalent disturbance torque at the end of the first motor (i.e., the "target motor" mentioned above) can be obtained as shown in the following formula (4): Formula (4) In the above formula (4), This refers to the equivalent disturbance torque corresponding to the first motor (i.e., the "target motor" mentioned above); This refers to the pumping torque generated by the engine; This refers to the ratio between the number of teeth on the ring gear and the number of teeth on the sun gear, i.e., the preset ring gear ratio, which belongs to the planetary gear set characteristic coefficient.

[0121] Furthermore, after obtaining the equivalent disturbance torque corresponding to the first motor (i.e., the "target motor" mentioned above), the equivalent disturbance torque can be directly multiplied by the target gain coefficient and the negative value can be used as the target compensation torque of the first motor (i.e., the "target motor" mentioned above), thereby counteracting the torque disturbance caused by the pump air pulsation torque and suppressing the vibration of the transmission system.

[0122] For example, assuming the target compensation torque of the first motor (i.e., the "target motor" mentioned above) is defined as T1, the target gain coefficient is defined as K, and the pump pulsation torque is defined as T2, then T1 = .

[0123] Furthermore, in order to determine the target compensation torque of the target motor more quickly, embodiments of this application can also construct a MAP table for determining compensation parameters in advance and store the constructed MAP table in the vehicle. When it is necessary to calculate the target compensation torque of the target motor, the corresponding MAP table can be directly queried to obtain the compensation parameters, and the target compensation torque of the target motor can be determined based on the compensation parameters, the target gain coefficient and the pump pulsation torque.

[0124] It should be understood that the methods provided in the embodiments of this application do not require modification of the core calculation logic; only minor adjustments to the MAP table are needed during the initial calibration stage. For example, for hybrid vehicles with a planetary gear set structure, the torque amplitude scaling characteristics and phase lag characteristics brought by the planetary gear set can be embedded into the MAP table during the initial calibration stage. Similarly, for hybrid vehicles with other structures, the compensation parameters at the corresponding speeds can be recalibrated for their specific vehicle type during the initial calibration stage without modifying the calculation logic.

[0125] In some embodiments, determining the target compensation torque of the target motor based on the pump pulsation torque and the target gain coefficient includes: determining the feedforward compensation torque of the target motor based on the pump pulsation torque and the current speed of the engine; and multiplying the target gain coefficient by the feedforward compensation torque to obtain the target compensation torque.

[0126] The feedforward compensation torque of the target motor is an intermediate compensation torque initially determined based on the pump pulsation torque and the current engine speed, used to counteract pump torque disturbances.

[0127] It is understandable that the pumping pulsation torque is the disturbance that causes torsional vibration in the transmission system, which can directly determine the basic amplitude of the compensation torque output by the target motor. The engine speed usually directly affects the generation frequency of the pumping pulsation torque and also corresponds to the inherent phase transmission characteristics of the transmission system. Therefore, based on the pumping pulsation torque and the current engine speed, the initial feedforward compensation torque that is adapted to counteract the pulsation disturbance can be accurately generated.

[0128] In some embodiments, determining the feedforward compensation torque of the target motor based on the pump pulsation torque and the current engine speed includes: determining a target amplitude compensation coefficient and a target phase compensation angle based on the current engine speed; updating the pump pulsation torque based on the target phase compensation angle to obtain the updated pump pulsation torque; and multiplying the updated pump pulsation torque by the target amplitude compensation coefficient to obtain the feedforward compensation torque of the target motor.

[0129] The target amplitude compensation coefficient mentioned above is a proportional coefficient obtained by matching the current engine speed; it is used to correct the amplitude scaling ratio of the pump pulsating torque after it is transmitted to the target motor through the transmission mechanism, so as to match the actual disturbance torque.

[0130] The aforementioned target phase compensation angle is the crankshaft angle offset obtained by matching the engine's current speed; it is used to compensate for the phase lag generated during the transmission of the engine's pumping pulsation torque to the target motor, so that the compensation torque output by the target motor precisely offsets the original pumping pulsation torque.

[0131] For example, a first MAP table relating engine speed to amplitude compensation coefficient and a second MAP table relating engine speed to phase compensation angle can be constructed in advance. After the first and second MAP tables are constructed, they can be stored in the vehicle's storage module. When determining the feedforward compensation torque of the target motor, the corresponding target amplitude compensation coefficient can be determined in the first MAP table based on the current engine speed, and the corresponding target phase compensation angle can be determined in the second MAP table.

[0132] Specifically, through bench testing or vehicle calibration testing, the engine's various operating speeds are traversed, and the actual amplitude scaling ratio and phase offset (i.e., the crankshaft angle difference after the pumping disturbance is transmitted to the target motor) corresponding to the pumping pulsation torque at each speed are recorded one by one. The results are then compiled into a first MAP table between the engine speed and the amplitude compensation coefficient, and a second MAP table between the engine speed and the phase compensation angle.

[0133] For example, the first MAP table mentioned above can be shown in Table 3 below: Table 3

[0134] In Table 3 above, X refers to the engine speed, measured in rpm; This refers to the amplitude compensation coefficient.

[0135] It should be understood that Table 3 above is only an example of the first MAP table. In addition to the correspondence shown in Table 3, the first MAP table may also contain the correspondence between the speed and amplitude compensation coefficient of other engines. This application embodiment does not limit this.

[0136] As shown in Table 3, the amplitude compensation coefficient generally increases with increasing engine speed.

[0137] Understandably, when the engine speed is low, the torsional damping of the transmission system is stronger and the torque transmission attenuation is more obvious. The equivalent amplitude of the pumping air pulsation torque transmitted to the target motor is smaller, so the corresponding amplitude compensation coefficient is lower. As the engine speed increases, the effect of torsional damping weakens and the torque transmission loss decreases. The equivalent amplitude of the pumping air pulsation torque transmitted to the target motor increases accordingly, so the corresponding amplitude compensation coefficient is higher.

[0138] For example, the second MAP table mentioned above can be shown in Table 4 below: Table 4

[0139] In Table 4 above, X refers to the engine speed, measured in rpm; This refers to the phase compensation angle, measured in degrees (°).

[0140] It should be understood that Table 4 above is only an example of a second MAP table. In addition to the correspondence shown in Table 4, the second MAP table may also contain the correspondence between the engine speed and the phase compensation angle of other engines. This application embodiment does not limit this.

[0141] As shown in Table 4, the phase compensation angle generally increases with increasing engine speed.

[0142] It is understandable that there is a fixed time delay when the pumping pulsating torque is transmitted in the transmission system. The higher the engine speed, the more angle the crankshaft rotates per unit time. The greater the crankshaft angle offset in the same time, the greater the phase lag angle generated by the pumping pulsating torque from the engine to the target motor. Therefore, a larger phase compensation angle needs to be set to offset this lag deviation.

[0143] For example, assuming the current engine speed is 1200 rpm, the target amplitude compensation coefficient corresponding to the current speed can be obtained by querying Table 3 as 0.35, and the target phase compensation angle corresponding to the current speed can be obtained by querying Table 4 as 17°.

[0144] Furthermore, after obtaining the target phase compensation angle from the table, the pump pulsation torque can be updated based on the target phase compensation angle to obtain the updated pump pulsation torque.

[0145] In some embodiments, updating the pumping pulsation torque based on the target phase compensation angle to obtain the updated pumping pulsation torque includes: compensating the current crankshaft angle of the engine based on the target phase compensation angle to obtain the compensated crankshaft angle; and determining the updated pumping pulsation torque based on the compensated crankshaft angle.

[0146] Understandably, as mentioned above, since the target phase compensation angle is used to compensate for the phase lag generated during the transmission of the engine's pumping pulsating torque to the target motor, the specific method for compensating the engine's current crankshaft angle based on the target phase compensation angle is to add the engine's current crankshaft angle and the target phase compensation angle to obtain the compensated crankshaft angle.

[0147] Furthermore, in order to ensure that the compensated crankshaft angle is precisely within the engine's effective operating cycle range (for example, for an L4 engine, the effective operating cycle range is [0, 720 degrees]), the compensated crankshaft angle can be normalized by taking a model.

[0148] The above-mentioned normalization process involves performing periodic normalization operations on the compensated crankshaft angles to convert and consolidate angles of any size into the effective working cycle range.

[0149] Furthermore, after obtaining the compensated crankshaft angle within the effective working cycle range of the engine, the basic pulsating torque corresponding to the current engine speed and the compensated crankshaft angle can be re-determined in the first preset correspondence, referring to the method described above. Then, the re-determined basic pulsating torque is multiplied by the target torque correction coefficient determined based on the current engine coolant temperature to obtain the updated pumping pulsating torque.

[0150] For example, assuming the current engine speed is 800 rpm, the current crankshaft angle is 270°, and the current coolant temperature is 25°, the original pump pulsation torque determined based on these parameters is 49.5 Nm. If the target phase compensation angle is determined to be 12° based on the current engine speed, the current crankshaft angle of the engine is compensated based on the target phase compensation angle, resulting in a compensated crankshaft angle of 282°. Based on the compensated crankshaft angle and the current engine speed, the first preset correspondence can be re-queried to determine the corresponding basic pulsation torque as 39 Nm. The target torque correction coefficient determined based on the current coolant temperature is 1.10, resulting in an updated pump pulsation torque of 42.9 Nm.

[0151] Furthermore, after obtaining the updated pump pulsation torque, the updated pump pulsation torque can be multiplied by the target amplitude compensation coefficient to obtain the feedforward compensation torque of the target motor.

[0152] For example, assuming the current engine speed is 800 rpm, the target amplitude compensation coefficient corresponding to the current speed is 0.32 obtained from Table 3. If the updated pump pulsation torque is 42.9 Nm, then the updated pump pulsation torque and the target amplitude compensation coefficient are multiplied to obtain the target motor feedforward compensation torque as 42.9 * 0.32 = 13.728 Nm.

[0153] After obtaining the feedforward compensation torque of the target motor, the feedforward compensation torque of the target motor can be multiplied by the target gain coefficient determined above to obtain the final target compensation torque.

[0154] For example, assuming the target motor feedforward compensation torque is 13.728 Nm and the target gain coefficient is 1, then multiplying the target motor feedforward compensation torque and the target gain coefficient gives the target compensation torque as 13.728 * 1 = 13.728 Nm.

[0155] By controlling the target motor to output the target compensation torque as determined above, the torque disturbance caused by the pumping pulsation torque generated during the engine start-up phase can be counteracted, which can effectively reduce the torsional vibration of the transmission system and improve driving comfort.

[0156] The above method matches the target amplitude compensation coefficient and target phase compensation angle based on the current engine speed, and corrects the pumping pulsation torque based on the target amplitude compensation coefficient and target phase compensation angle. This can offset the phase lag and amplitude attenuation caused by the transmission path in advance, so that the determined target motor feedforward compensation torque can accurately match the actual torque disturbance at the motor end. This achieves precise offsetting of the pumping pulsation torque generated by the engine, effectively suppresses transmission torsional vibration, and improves driving comfort.

[0157] Figure 3 This is a schematic diagram of the structure of a vehicle control device provided in an embodiment of this application.

[0158] For example, the device is applied to a hybrid vehicle, which includes an engine and a target electric motor; like Figure 3 As shown, the device 300 includes: The acquisition module 301 is used to acquire the current operating parameters of the engine.

[0159] The first determining module 302 is used to determine the pumping pulsation torque and target gain coefficient generated when the engine is started by being driven by the target motor, based on the engine's current operating parameters.

[0160] The second determining module 303 is used to determine the target compensation torque of the target motor based on the pump air pulsation torque and the target gain coefficient.

[0161] The control module 304 is used to control the target motor to output the target compensation torque in order to counteract the vibration of the transmission system caused by the pump air pulsation torque.

[0162] In some embodiments, the second determining module is specifically used to: determine the feedforward compensation torque of the target motor based on the pump pulsation torque and the current speed of the engine; and multiply the target gain coefficient by the feedforward compensation torque to obtain the target compensation torque.

[0163] In some embodiments, the second determining module includes a determining unit, which is specifically used to: determine a target amplitude compensation coefficient and a target phase compensation angle based on the current engine speed; update the pump pulsation torque based on the target phase compensation angle to obtain an updated pump pulsation torque; and multiply the updated pump pulsation torque by the target amplitude compensation coefficient to obtain the feedforward compensation torque of the target motor.

[0164] In some embodiments, the determining unit includes an updating subunit, which is specifically used to: compensate the current crankshaft angle of the engine based on the target phase compensation angle to obtain the compensated crankshaft angle; and determine the updated pumping pulsation torque based on the compensated crankshaft angle.

[0165] In some embodiments, the current operating parameters include the current engine speed, and the first determining module is further specifically configured to: determine a first gain coefficient as a target gain coefficient when the current speed is within a preset speed range; wherein the preset speed range is the speed range that causes resonance in the vehicle's transmission system; the first gain coefficient is greater than zero; and determine a second gain coefficient as a target gain coefficient when the current speed is not within the preset speed range; wherein the second gain coefficient is equal to zero.

[0166] In some embodiments, the current operating parameters include the current engine speed and the number of engine cylinders. The first determining module is further specifically used to: determine the generation frequency of the pump pulsating torque based on the current engine speed and the number of engine cylinders; obtain the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper; and determine the target gain coefficient based on the generation frequency of the pump pulsating torque, the resonance frequency and bandwidth adjustment coefficient of the torsional vibration damper.

[0167] In some embodiments, the current operating parameters include the engine's current crankshaft state parameters and the current coolant temperature. The first determining module is further specifically configured to: determine the basic pulsating torque corresponding to the current crankshaft state parameters based on a first preset correspondence; wherein the first preset correspondence is used to characterize the correspondence between the engine's crankshaft state parameters and the basic pulsating torque; determine the target torque correction coefficient corresponding to the current coolant temperature based on a second preset correspondence; wherein the second preset correspondence is used to characterize the correspondence between the engine's coolant temperature and the torque correction coefficient used to correct the basic pulsating torque; and multiply the basic pulsating torque and the target torque correction coefficient to obtain the pumping pulsating torque.

[0168] In some embodiments, if the vehicle further includes a planetary gear set, the engine is connected to the target motor via the planetary gear set. The planetary gear set includes a sun gear, a planet carrier, and a ring gear. The sun gear is connected to the target motor, the planet carrier is connected to the engine, and the ring gear is connected to the vehicle's power output shaft. The second determining module is further specifically used to: determine the equivalent disturbance torque of the target motor based on the pumping pulsation torque and a preset ring gear ratio; wherein, the preset ring gear ratio is the ratio between the number of teeth on the ring gear and the number of teeth on the sun gear; and multiply the target gain coefficient by the equivalent disturbance torque to obtain the target compensation torque.

[0169] Figure 4 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application.

[0170] For example, such as Figure 4 As shown, the vehicle 400 includes a memory 401 and a processor 402. The memory 401 stores executable program code 4011, and the processor 402 is used to call and execute the executable program code 4011 to perform a vehicle control method.

[0171] Furthermore, embodiments of this application also protect an apparatus that may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to perform a vehicle control method provided in embodiments of this application.

[0172] This embodiment can divide the device into functional modules based on the above method example. For example, each module can correspond to a separate function, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0173] When the functional modules are divided according to their respective functions, the device may further include an acquisition module, a first determination module, a second determination module, and a control module. It should be noted that all relevant content regarding the steps involved in the above method embodiments can be referenced to the functional descriptions of the corresponding functional modules, and will not be repeated here.

[0174] It should be understood that the device provided in this embodiment is used to execute the above-described vehicle control method, and therefore can achieve the same effect as the above-described implementation method.

[0175] When using an integrated unit, the device may include a processing module and a storage module. When the device is applied to a vehicle, the processing module can be used to control and manage the vehicle's movements. The storage module can be used to support the vehicle in executing relevant program code and data.

[0176] The processing module may be a processor or a controller, which can implement or execute various exemplary logic blocks, modules, and circuits shown in conjunction with the disclosure of this application. The processor may also be a combination of functions that implement computing capabilities, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc., and the storage module may be a memory.

[0177] In addition, the device provided in the embodiments of this application may specifically be a chip, component or module. The chip may include a connected processor and a memory. The memory is used to store instructions. When the processor calls and executes the instructions, the chip can execute a vehicle control method provided in the above embodiments.

[0178] This embodiment also provides a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the above-described related method steps to implement a vehicle control method provided in the above embodiment.

[0179] This embodiment also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned steps to implement a vehicle control method provided in the above embodiment.

[0180] In this embodiment, the device, computer-readable storage medium, computer program product, or chip are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0181] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0182] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus 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 device, or some features may be ignored or not executed. Furthermore, the 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.

[0183] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for controlling a vehicle, characterized in that, The method is applied to a hybrid vehicle, the vehicle comprising: an engine and a target electric motor, the method comprising: Obtain the current operating parameters of the engine; Based on the current operating parameters of the engine, determine the pumping pulsation torque and target gain coefficient generated when the engine is started by the target motor; The target compensation torque of the target motor is determined based on the pump pulsation torque and the target gain coefficient. The target motor is controlled to output the target compensation torque to counteract the vibration of the transmission system caused by the pump air pulsation torque.

2. The method according to claim 1, characterized in that, Determining the target compensation torque of the target motor based on the pump pulsation torque and the target gain coefficient includes: Based on the pump pulsation torque and the current speed of the engine, the feedforward compensation torque of the target motor is determined; The target compensation torque is obtained by multiplying the target gain coefficient by the feedforward compensation torque.

3. The method according to claim 2, characterized in that, Determining the feedforward compensation torque of the target motor based on the pump pulsation torque and the current speed of the engine includes: Based on the current engine speed, determine the target amplitude compensation coefficient and the target phase compensation angle; Based on the target phase compensation angle, the pump pulsation torque is updated to obtain the updated pump pulsation torque. The updated pump pulsation torque is multiplied by the target amplitude compensation coefficient to obtain the feedforward compensation torque of the target motor.

4. The method according to claim 3, characterized in that, The step of updating the pump pulsation torque based on the target phase compensation angle to obtain the updated pump pulsation torque includes: Based on the target phase compensation angle, the current crankshaft angle of the engine is compensated to obtain the compensated crankshaft angle; Based on the compensated crankshaft angle, the updated pump pulsation torque is determined.

5. The method according to claim 1 or 2, characterized in that, The current operating parameters include the current engine speed, and determining the target gain coefficient based on the current operating parameters of the engine includes: When the current speed is within a preset speed range, the first gain coefficient is determined as the target gain coefficient; wherein, the preset speed range is the speed range that causes resonance in the transmission system of the vehicle; and the first gain coefficient is greater than zero. If the current rotational speed is not within the preset rotational speed range, the second gain coefficient is determined as the target gain coefficient; wherein the second gain coefficient is equal to zero.

6. The method according to claim 1 or 2, characterized in that, The current operating parameters include the current engine speed and the number of cylinders in the engine. Determining the target gain coefficient based on the current operating parameters of the engine includes: The frequency of pump pulsation torque generation is determined based on the current engine speed and the number of cylinders in the engine. The resonant frequency and bandwidth adjustment coefficient of the torsional vibration damper are obtained, and the target gain coefficient is determined based on the generation frequency of the pump air pulsation torque, the resonant frequency of the torsional vibration damper, and the bandwidth adjustment coefficient.

7. The method according to claim 1, characterized in that, The current operating parameters include the current crankshaft status parameters and current coolant temperature of the engine. Determining the pumping pulsation torque generated when the engine is started by the target motor based on the current operating parameters includes: Based on a first preset correspondence, a basic pulsating torque corresponding to the current crankshaft state parameters is determined; wherein, the first preset correspondence is used to characterize the correspondence between the crankshaft state parameters of the engine and the basic pulsating torque; Based on the second preset correspondence, a target torque correction coefficient corresponding to the current water temperature is determined; wherein, the second preset correspondence is used to characterize the correspondence between the engine water temperature and the torque correction coefficient used to correct the basic pulsating torque; The pump pulsating torque is obtained by multiplying the basic pulsating torque and the target torque correction coefficient.

8. The method according to claim 1, characterized in that, If the vehicle also includes a planetary gear set, the engine is connected to the target motor through the planetary gear set. The planetary gear set includes a sun gear, a planet carrier, and a ring gear. The sun gear is connected to the target motor, the planet carrier is connected to the engine, and the ring gear is connected to the power output shaft of the vehicle. Determining the target compensation torque of the target motor based on the pump pulsation torque and the target gain coefficient includes: Based on the pump pulsating torque and the preset gear ratio, the equivalent disturbance torque of the target motor is determined; wherein, the preset gear ratio is the ratio between the number of teeth on the gear ring and the number of teeth on the sun gear. The target compensation torque is obtained by multiplying the target gain coefficient by the equivalent disturbance torque.

9. A vehicle, characterized in that, The vehicles include: Memory, used to store executable program code; A processor for calling and running the executable program code from the memory, causing the vehicle to perform the method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the method as described in any one of claims 1 to 8.

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