An engine torque control method, system, storage medium and vehicle

Abstract

The application provides an engine torque control method, system, storage medium and vehicle, which is applied to a hybrid vehicle. The method comprises the following steps: acquiring an operation condition distribution diagram of the vehicle under different working conditions, wherein the operation condition diagram is characterized by a distribution trend of engine torque and engine speed under different throttle opening degrees; obtaining a plurality of groups of engine torque under different throttle opening degrees and different engine speeds based on the operation condition distribution diagram; determining a plurality of groups of target demand torque of the vehicle based on the plurality of groups of engine torque; establishing a torque control boundary line under a corresponding working condition based on the plurality of groups of target demand torque; and controlling the vehicle under the corresponding working condition to adjust the current engine torque according to the torque control boundary line. Through the method provided by the application, the problem of the existence of a loud buzzing sound in the vehicle under the working condition of low SOC, small throttle and medium-low vehicle speed of the hybrid vehicle is solved.

Description

Technical Field

[0001] This application relates to the field of NVH technology for hybrid vehicles, and in particular to an engine torque control method, system, storage medium, and vehicle. Background Technology

[0002] Hybrid Electric Vehicles (HEVs) are automobiles that combine an engine and an electric motor into a hybrid system. Different types of hybrid vehicles have different torque control strategies, but at low SOC (State of Charge), all hybrid vehicles rely on the engine to provide torque, while the electric motor can provide additional torque to enhance power. Engine torque refers to the torque output from the crankshaft and is one of the main indicators for vehicles equipped with an engine. Maximum torque generally occurs in the low to medium engine speed range, and decreases as the engine speed increases further.

[0003] In hybrid vehicles, under conditions of low SOC, low to medium throttle, and low to medium speed, the engine will charge the battery, and the electric motor will also contribute to torque output as the SOC gradually increases. This results in higher engine torque, which transmits noise in a 2 / 4 order structure into the cabin, causing a noticeable humming sound in the cabin. This can cause discomfort and a feeling of oppression for the driver and passengers. Summary of the Invention

[0004] In view of the above problems, one objective of this application is to provide an engine torque control method to solve the problem of obvious humming noise in the cab of hybrid vehicles under certain operating conditions; a second objective of this application is to provide an engine torque control system to improve the NVH performance of the whole vehicle; a third objective of this application is to provide a computer-readable storage medium; and a fourth objective of this application is to provide a vehicle.

[0005] To achieve the above objectives, the first aspect of this invention provides an engine torque control method, the technical solution of which is implemented as follows:

[0006] An engine torque control method, applied to a hybrid vehicle, the method comprising:

[0007] Obtain the operating condition distribution map of the vehicle under different operating conditions. The operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings.

[0008] Based on the operating condition distribution map, multiple sets of engine torques are obtained under different throttle openings and different engine speeds;

[0009] Based on the multiple sets of engine torques, multiple sets of target required torques for the vehicle are determined, wherein the target required torques are the engine limit torques that meet the noise evaluation standards.

[0010] Based on the multiple sets of target torque requirements, establish torque control boundary lines under corresponding operating conditions;

[0011] Based on the torque control boundary line, the vehicle under the corresponding operating condition adjusts its current engine torque.

[0012] Optionally, obtaining the vehicle's operating condition distribution map under different operating conditions includes:

[0013] Obtain the operating condition distribution map of the vehicle under target operating conditions, wherein the target operating conditions include one or more of the following: battery charge is less than or equal to a first threshold, throttle opening is within a first range, and vehicle speed is within a second range.

[0014] Optionally, determining the multiple sets of target torque requirements for the vehicle based on multiple sets of engine torques includes:

[0015] The test measures the calibrated noise level corresponding to the calibrated torque at the target throttle opening and target speed; wherein the calibrated torque is used to indicate the engine torque when the vehicle is noisy.

[0016] Based on the calibrated torque, the reference noise level of the reference torque that has a positive or negative difference from the calibrated torque is tested;

[0017] The reference noise level is evaluated to determine the target torque required by the vehicle at the corresponding target throttle opening and target speed.

[0018] Optionally, evaluating the reference noise level and determining the target torque required by the vehicle at the corresponding target throttle opening and target speed includes:

[0019] By comparing the reference noise levels of reference torques with positive and negative differences, it is determined whether the corresponding reference noise levels meet the noise evaluation criteria.

[0020] The limit reference torque that meets the noise evaluation standard is determined as the target required torque, and the limit reference torque represents the upper limit value of the torque corresponding to meeting the noise evaluation standard.

[0021] Optionally, the test items corresponding to the calibrated noise level and / or the reference noise level include at least one of in-vehicle noise, seat rail vibration, active and passive side vibration of the suspension, engine parameters, and electric motor parameters.

[0022] Optionally, establishing the torque control boundary line under the corresponding operating condition based on multiple sets of target torque requirements includes:

[0023] The target torque requirements under the corresponding working conditions are input into the regression model for linear regression analysis to obtain the torque control boundary line.

[0024] Optionally, controlling the vehicle under the corresponding operating condition to adjust the current engine torque according to the torque control boundary line includes:

[0025] Obtain the current operating conditions of the vehicle and the current engine torque of the vehicle;

[0026] Based on the torque control boundary line, the current engine torque of the vehicle is adjusted to be less than or equal to the torque data on the torque control boundary line under the current operating conditions.

[0027] A second aspect of the present invention also provides an engine torque control system applied to a hybrid vehicle, the system comprising:

[0028] The data collection module is used to acquire the operating condition distribution map of the vehicle under different operating conditions. The operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings.

[0029] The data analysis module is used to obtain multiple sets of engine torques under different throttle openings and different engine speeds based on the operating condition distribution map.

[0030] The torque confirmation module is used to determine the target torque required by the vehicle at a corresponding throttle opening based on multiple sets of engine torques distributed under different throttle openings. The target torque required is the engine limit torque that meets the noise evaluation standard.

[0031] The data processing module is used to establish torque control boundary lines under corresponding operating conditions based on multiple sets of target torque requirements.

[0032] The vehicle execution module is used to control the vehicle to adjust the current engine torque under the corresponding operating conditions according to the torque control boundary line.

[0033] Optionally, the data collection module includes:

[0034] The acquisition module is used to acquire the operating condition distribution map of the vehicle under target operating conditions, wherein the target operating conditions include one or more of the following: battery charge is less than or equal to a first threshold, throttle opening is within a first range, and vehicle speed is within a second range.

[0035] Optionally, the torque confirmation module includes:

[0036] The testing module is used to test the calibration noise level corresponding to the calibration torque at the target throttle opening and target speed; wherein, the calibration torque is used to indicate the engine torque when the vehicle is noisy;

[0037] The test submodule is used to test the reference noise level of a reference torque that has a positive or negative difference from the calibration torque, based on the calibration torque.

[0038] The determination submodule is used to evaluate the reference noise level and determine the target torque required by the vehicle at the corresponding target throttle opening and target speed.

[0039] Optionally, the determining submodule includes:

[0040] The comparison module is used to compare the reference noise levels of reference torque with positive difference values ​​and reference torque with negative difference values, and to determine whether the corresponding reference noise levels meet the noise evaluation criteria.

[0041] The judgment module is used to determine the limit reference torque that meets the noise evaluation standard as the target required torque, wherein the limit reference torque is the upper limit value of the torque corresponding to meeting the noise evaluation standard.

[0042] Optionally, the data processing module includes:

[0043] The analysis module is used to input multiple sets of the target torque requirements under the corresponding working conditions into the regression model for linear regression analysis to obtain the torque control boundary line.

[0044] Optionally, the vehicle execution module includes:

[0045] The current acquisition module is used to acquire the current operating conditions of the vehicle and the current engine torque of the vehicle;

[0046] The current execution module is used to adjust the current engine torque of the vehicle to be less than or equal to the torque data on the torque control boundary line under the current operating conditions, based on the torque control boundary line.

[0047] A third aspect of the present invention also provides a computer-readable storage medium having instructions stored thereon that, when executed by one or more processors, cause the processors to perform the steps of one or more methods as provided in the first aspect of the present invention.

[0048] A fourth aspect of the present invention also provides a vehicle that performs the engine torque control method as provided in the first aspect of the present invention, and / or is equipped with the engine torque control system provided in the second aspect of the present invention.

[0049] Compared with existing technologies, the engine torque control method of the present invention has the following advantages:

[0050] The engine torque control method described in this invention is applied to a hybrid vehicle. The method includes: acquiring an operating condition distribution map of the vehicle under different operating conditions, wherein the operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings; determining multiple target torque requirements for the vehicle based on multiple sets of engine torques, wherein the target torque requirements are the engine limit torque that meets noise evaluation standards; establishing torque control boundary lines for corresponding operating conditions based on the multiple sets of target torque requirements; and controlling the vehicle under the corresponding operating condition to adjust the current engine torque according to the torque control boundary lines.

[0051] When implementing this method, engine speed and torque under different throttle openings can be compared according to different vehicle operating conditions to analyze torque distribution trends, understand vehicle NVH performance, and evaluate vehicle comfort and quietness. By changing the engine torque output and observing changes in in-vehicle noise, the target torque required by the vehicle under corresponding operating conditions can be determined, thereby establishing a linear and operable torque control boundary line. In this way, the vehicle can automatically control engine torque according to the torque control boundary line and current operating conditions to meet the performance requirements under actual operating conditions. This not only covers the torque requirement target but also solves the in-vehicle noise problem caused by high torque, providing optimal driving and noise performance.

[0052] The engine torque control system and the vehicle provided in this embodiment of the invention have the same advantages as the engine torque control method described above compared to the prior art, and will not be repeated here. Attached Figure Description

[0053] To more clearly illustrate the technical solution of this application, the drawings used in the description of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 This is a flowchart illustrating the steps of the engine torque control method according to an embodiment of this application;

[0055] Figure 2 This is an embodiment of the present application illustrating the operating condition distribution diagram of the vehicle. Detailed Implementation

[0056] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0057] It's important to note that in hybrid vehicles, both the engine and the electric motor can provide torque. The accelerator pedal is typically used to control vehicle speed, indicating the desired overall power output. Normally, when the driver presses the accelerator pedal, the vehicle's ECU can understand the driver's intentions based on the pedal's position and rate of change. The hybrid vehicle's control system simultaneously considers the torque and power distribution from both the engine and generator, achieving optimal power output and energy utilization while meeting the driver's driving needs.

[0058] The engine's torque can be adjusted by controlling factors such as intake air volume, fuel injection volume, and ignition timing; the electric motor's torque can be adjusted by controlling factors such as current, voltage, and magnetic field. The control system monitors the battery's state of charge (SOC) in real time. If the battery has sufficient charge, the control system will tend to use the electric motor for power. If the battery charge is low, the hybrid vehicle will typically rely on the engine for power.

[0059] At low SOC, the inventors of this invention discovered a noticeable humming sound in the driver's cab, and collected data to obtain the following results: Figure 2 The operating condition distribution diagram shown is as follows: Figure 2 The diagram shown illustrates an exemplary operating condition distribution of a vehicle according to some embodiments of this disclosure, under normal circumstances, the entire... Figure 2 It should show a trend of high on the upper right and low on the lower left. The data results show that the torque is relatively high in some operating conditions under 30% to 50% throttle acceleration, resulting in an inconsistent trend of engine torque.

[0060] After detailed analysis of the operating conditions, it was found that the engine speed and torque distribution were unreasonable under different throttle acceleration conditions. The torque / speed distribution of the engine under 30% to 50% throttle acceleration was nonlinear, with the speed distribution being too low and the torque distribution being too high at these low and medium throttle conditions. After testing and troubleshooting, the problem was found to be:

[0061] When the State of Charge (SOC) is too low, the engine outputs insufficient electrical energy. The engine will then intervene to charge the battery or directly drive the wheels, while the electric motor will also participate in driving the vehicle, directly affecting fuel consumption and power performance. Due to the charging and electric motor torque participation in hybrid vehicles, under conditions of low to medium throttle (30%–50%) and low to medium speeds (30 km / h–60 km / h), the engine torque is relatively high, altering the crankshaft speed and affecting the conditions and extent of second and fourth-order combustion. This can easily manifest as second and fourth-order structural noise transmission, resulting in a noticeable humming sound inside the vehicle.

[0062] It's important to explain that 2nd / 4th order structural noise transmission can be understood as the vibration noise generated by the engine's 2nd / 4th order combustion under certain operating conditions. This noise can be further transmitted into the vehicle interior through engine mounts and body structures (chassis, seats, frame, etc.), making the humming sound noticeable inside the cabin and reducing the vehicle's NVH performance. "2nd / 4th order" can refer to the frequency or vibration mode of the noise, where 2nd / 4th order can represent the engine's 2nd or 4th order harmonics. A significantly higher engine torque indicates increased combustion pressure inside the engine, increasing the probability of more vibration. This vibration is superimposed on the vibration noise generated by the 2nd / 4th order combustion itself, making the humming sound inside the vehicle even more pronounced.

[0063] In view of this, the present invention aims to provide an engine torque control method. Based on actual operating conditions and noise test data, and after multiple rounds of verification and evaluation, the NVH control boundary line of engine speed / torque is summarized. By controlling the engine torque below the boundary line, the in-vehicle noise can meet the limit requirements and reach an acceptable level.

[0064] Example 1

[0065] Combination Figure 1 and Figure 2 As shown, Figure 1 A flowchart illustrating the steps of an engine torque control method according to the present invention is shown; applied to hybrid vehicles, the method includes:

[0066] Step S1: Obtain the operating condition distribution map of the vehicle under different operating conditions. The operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings.

[0067] This solution can collect operating condition distribution maps of vehicles under different operating conditions. For example, under specific operating conditions, engine speed and torque data at different throttle openings can be obtained through actual testing or simulation testing. Figure 2The diagram shows the torque-speed distribution under different throttle openings. Data can be collected on a vehicle test bench or on actual roads. From the operating condition distribution diagram, we can understand the engine's characteristic curves, that is, the maximum and minimum torque that the engine can output at different throttle openings, and the speed range corresponding to each torque.

[0068] It is understood that, in actual vehicle use, hybrid vehicles are prone to humming noise mainly at low SOC, low to medium throttle, and low to medium speeds. Therefore, a target operating condition for the vehicle can be set, and an operating condition distribution map of the vehicle under the target condition can be obtained. The target operating condition includes one or more of the following: battery charge less than or equal to a first threshold, throttle opening within a first range, and vehicle speed within a second range. The first threshold can be a battery charge of 60%, the first range can be a throttle opening of 30% to 50%, and the second range can be a vehicle speed of 30 km / h to 60 km / h, thereby specifically understanding the torque trend map related to noise. In this embodiment, different throttle openings can be integer throttle openings increasing in 10% increments. For example, engine speed and torque data can be collected for seven sets of throttle openings ranging from 20% to 80%. In some embodiments, the increment can be changed, and multiple combinations of throttle openings can be selected.

[0069] For example, the following describes the actual operating conditions of 40% to 60% SOC, D1 gear creeping with 30% throttle acceleration to 90 km / h, and the determination of the target torque required under these operating conditions.

[0070] The throttle opening can be obtained by the position sensor on the throttle pedal.

[0071] Step S2: Based on the operating condition distribution map, obtain multiple sets of engine torques under different throttle openings and different engine speeds;

[0072] Based on the obtained operating condition distribution map, the collected data can be analyzed in detail to obtain the different engine speeds and engine torques corresponding to each group of throttle openings. There is a one-to-one correspondence between each engine torque and each engine speed. Thus, multiple groups of engine torques under different throttle openings and different engine speeds can be obtained to understand the distribution trend of engine torque under low SOC conditions.

[0073] Step S3: Based on the multiple sets of engine torques, determine the multiple sets of target required torques for the vehicle, wherein the target required torques are the engine limit torques that meet the noise evaluation standards;

[0074] In this scheme, each group of throttle openings includes multiple torque data and corresponding speed data. Noise tests can be performed on the vehicle interior corresponding to each torque data under the 7 groups of throttle openings, and in-vehicle noise data can be collected. Based on the noise evaluation standard, the torque data under each group of throttle openings that meet and do not meet the noise evaluation standard can be judged.

[0075] Noise data in this scheme can be obtained by installing noise measurement devices, such as noise meters, sound analyzers, or sound sensors, at different locations on the vehicle. The noise evaluation standard can be understood as a preset noise acceptance level that meets human ear comfort. For example, the noise evaluation standard can be based on subjective human perception, where a representative group of people can conduct noise assessments to determine whether the noise level inside the vehicle corresponding to each torque data point is acceptable; if acceptable, the noise evaluation standard is met. Alternatively, the noise evaluation standard can be based on objective noise indicators, specifically the maximum permissible noise level for road vehicles under different speeds, loads, and operating conditions. Test personnel can use professional noise measurement equipment to collect the noise level of each torque data point and compare it with the maximum permissible noise level to determine whether it meets the noise evaluation standard.

[0076] It's understandable that the target torque requirement can be viewed as a range of target torque values ​​within a certain range, and this range is related to the degree of audibility of the humming sound. This range is derived from testing and analysis to ensure that the vehicle's internal noise remains at an acceptable level under specific operating conditions (e.g., low SOC, low to medium throttle, low to medium speed). For example, within the torque range of 230 N·m to 260 N·m at 30% throttle opening, different levels of audible humming sound are produced. Therefore, torque values ​​below 230 N·m to 260 N·m represent multiple torque data points that meet noise evaluation standards.

[0077] Specifically, the target torque requirement is the engine's limit torque that precisely meets the noise evaluation standard. The engine's limit torque can be defined as the maximum torque the engine can produce while meeting the noise evaluation standard requirements, slightly lower than or equal to that value. For example, if a vehicle produces an unacceptable humming sound at 230 N·m of torque with 30% throttle opening, then the noise evaluation standard is met within the torque range of 0–230 N·m. Therefore, a torque range of 210–230 N·m can be chosen as the target torque requirement to ensure that the vehicle provides sufficient power at this target torque while avoiding excessive torque that could lead to cabin noise.

[0078] In step S3, the specific steps for determining the target torque requirement can be as follows:

[0079] Step S31: Test the calibration noise level corresponding to the calibration torque at the target throttle opening and target speed; wherein, the calibration torque is used to indicate the engine torque when the vehicle has noise.

[0080] In this embodiment, the target throttle opening is the throttle opening selected from the seven groups of throttle openings that produces a buzzing sound inside the vehicle. For example... Figure 2 As shown in the figure, based on the analysis of the operating condition distribution diagram, it is understood that a buzzing sound appeared in multiple torque ranges under the vehicle with throttle opening of 30% to 50%. In order to save testing steps and test costs, three throttle openings of 30%, 40% and 50% can be selected as target throttle openings, and corresponding noise tests can be carried out under these three throttle openings.

[0081] Since the accepted noise level typically does not directly correspond to a fixed value, but rather to multiple sets of torque data when a humming sound is tested or identified, specifically, taking a 30% throttle opening as an example, a humming sound can be identified within the torque range of 230 N·m to 260 N·m. However, the difference in the degree of humming sound identification within this range is low, making it impossible to determine the specific torque value corresponding to the initial identified humming sound, or in other words, the humming sounds of multiple adjacent values ​​are nearly identical. Therefore, in this embodiment of the invention, 230 N·m to 260 N·m can be selected as the calibration torque to test the calibration noise level within this calibration torque range.

[0082] In some embodiments, the test items corresponding to the calibration noise level may include at least one of in-vehicle noise, seat rail vibration, active and passive side vibration of the suspension, engine parameters, and motor parameters. The calibration noise level can be obtained by testing at different measurement points in the vehicle. Specifically, in some embodiments, a sound analyzer can be placed inside the vehicle to obtain the in-vehicle noise level. In some embodiments, a vibration sensor or accelerometer can be used to measure the amplitude and frequency of seat vibration to obtain seat rail vibration; in some embodiments, a vibration sensor or accelerometer can be used to measure the active and passive vibrations of the vehicle's suspension system, for example, the vibration of the active and passive sides of the right suspension can be measured by a sensor installed on the right suspension. In some embodiments, engine parameters such as engine speed, torque, and cylinder detonation frequency can be obtained by sensors installed on the engine control system that monitor and record parameters related to engine vibration. In some embodiments, motor parameters of the P2 motor can be obtained by sensors installed on the motor control system that monitor and record parameters related to engine vibration; these motor parameters may include motor speed and motor torque.

[0083] Among them, the engine control system, the electric motor control system, and other systems related to power transmission and vibration can output engine parameters and electric motor parameters through data communication on the CAN bus.

[0084] Since in-vehicle noise, seat rail vibration, active and passive side vibration of the suspension, engine parameters and electric motor parameters are all closely related to NVH performance, these parameters can help assess the vibration and noise levels of the powertrain. Therefore, comprehensively calibrating the above noise levels can provide comprehensive information related to the vehicle's NVH, and assess the vehicle's NVH performance at the corresponding measurement points to ensure that the vehicle provides a quiet, comfortable and smooth driving experience under different operating conditions.

[0085] Step S32: Based on the calibrated torque, test the reference noise level of the reference torque that has a positive or negative difference from the calibrated torque;

[0086] In this scheme, corresponding tests can be performed on each calibrated torque, and the reference noise level of a reference torque with a positive or negative difference from the calibrated torque can be tested, which can more accurately obtain fixed and representative torque data. For the same throttle opening, by increasing or decreasing the torque, the noise effect is compared and verified, thereby determining whether the noise level corresponding to the calibrated torque is within an acceptable range.

[0087] Specifically, tests have shown that by altering the engine's torque output, a positive difference exists between the reference torque and the rated torque, while a negative difference exists. The changes in cabin noise after these torque changes can then be observed. More specifically, the engine torque can be increased by increasing fuel supply or raising the ignition timing through the engine control system. Conversely, the engine torque can be decreased by reducing fuel supply or retarding ignition timing through the engine control system.

[0088] The testing methods for the reference noise level are the same as those for the calibration noise level, and will not be elaborated further here. It is worth noting that the test items for the calibration noise level and the reference noise level should be the same.

[0089] Step S33: Evaluate the reference noise level and determine the target torque required by the vehicle at the corresponding target throttle opening and target speed.

[0090] By observing the changes in in-vehicle noise after altering torque and comparing the noise reduction effects, the target torque requirement can be determined. While changing the engine's torque output, the ECU can monitor engine operating parameters in real time, such as torque, speed, and throttle position, and perform noise measurements to assess the impact of engine torque changes on the vehicle's interior noise level. By comparing reference noise levels under different torque conditions, the impact of increasing or decreasing torque on in-vehicle noise can be evaluated, yielding test results. Multiple target torque requirements for the vehicle are obtained by using the target torque corresponding to various throttle openings.

[0091] In conjunction with the above embodiments, step S33 specifically includes:

[0092] Step S331: Compare the reference noise levels of the reference torque with a positive difference value and the reference torque with a negative difference value, and determine whether the corresponding reference noise level meets the noise evaluation standard.

[0093] Step S332: Determine the limit reference torque that meets the noise evaluation standard as the target required torque. The limit reference torque represents the upper limit value of the torque that meets the noise evaluation standard.

[0094] Specifically, if the calibrated torque is 230 N·m, the noise level of the reference torque parameter is tested when the engine torque increases or decreases by 10 N·m to 20 N·m. In a specific embodiment, when the engine torque increases by 10 N·m to 20 N·m, a buzzing sound can be detected at 30% throttle opening, and the noise increases with increasing torque; when the engine torque decreases by 10 N·m to 20 N·m, the buzzing sound is not obvious at 30% throttle opening, and the evaluation is acceptable. Based on this test result, 230 - (10 to 20) N·m can be regarded as the target torque requirement. In actual driving, under the conditions of 40% to 60% SOC, creeping in D1 gear with 30% throttle acceleration to 90 km / h, controlling the engine torque at 230 - (10 to 20) N·m can cover the torque requirement target and solve the in-vehicle noise problem caused by high torque.

[0095] It should be explained that if the calibrated torque is 230 N·m, and increasing the engine torque by 10 N·m to 20 N·m still results in no detectable humming sound at 30% throttle opening, then the limit reference torque that meets the noise evaluation standard is determined as the target required torque. In this embodiment, the limit reference torque can be the engine's limit torque that just meets the noise evaluation standard. The engine's limit torque can be the maximum torque value that the engine can produce while meeting the noise evaluation standard requirements, which is slightly lower than or equal to the maximum. For example, if the vehicle still cannot detect humming sound at a torque of 230 + (10 to 20) N·m at 30% throttle opening, then the engine torque can be further increased to 230 + (X to Y) N·m until humming sound can be detected at certain values ​​of X and Y. As the torque increases, the noise increases. This 230 + (X to Y) N·m can be regarded as the upper limit of the torque corresponding to meeting the noise evaluation standard. Within this torque range, humming sound can begin to be detected, and this limit reference torque can be used as the target required torque.

[0096] It should be explained that if the calibrated torque is 230 N·m, and a humming sound can still be detected at 30% throttle opening after reducing the engine torque by 10 N·m to 20 N·m, then the limit reference torque that meets the noise evaluation standard is determined as the target required torque. In this embodiment, the limit reference torque can be the engine's limit torque that just meets the noise evaluation standard. The engine's limit torque can be the maximum torque value that the engine can produce while meeting the noise evaluation standard requirements, which is slightly lower than or equal to the maximum torque value. For example, if a humming sound can still be detected at 230 - (10 to 20) N·m of torque at 30% throttle opening, then the engine torque can be further reduced to 230 - (X to Y) N·m until a humming sound can be detected at both X and Y values. As the torque increases, the noise increases. This 230 - (X to Y) N·m can be regarded as the upper limit of the torque corresponding to meeting the noise evaluation standard. Within this torque range, a humming sound can be detected, and this limit reference torque can be used as the target required torque.

[0097] Similarly, when the calibrated torque is other torque data, the reference noise level before and after the difference from the calibrated torque is tested in the same way. A humming sound can be identified in both cases. When the noise increases with the increase of torque, the target required torque is determined.

[0098] Thus, by measuring the noise level before and after each calibrated torque, the impact of calibrated torque changes on noise can be assessed more accurately. This helps ensure that the target torque meets noise evaluation standards while being as close as possible to the vehicle's performance limits. Furthermore, in actual operating conditions, quickly adjusting engine torque and measuring the noise level of the reference torque makes it easier to determine the torque change required under specific conditions.

[0099] Step S4: Based on the multiple sets of target torque requirements, establish torque control boundary lines under the corresponding operating conditions;

[0100] In this scheme, seven throttle openings correspond to seven target torque requirements. Multiple target torque requirements under corresponding operating conditions can be input into a regression model for linear regression analysis to obtain the torque control boundary line, which describes the torque requirement range under different throttle openings. Specifically, multiple data points (each throttle opening corresponding to a target torque requirement range value) can be input into the regression model, and the speed / torque boundary line can be fitted based on these data points to represent the NVH performance target of the vehicle under different torque requirement ranges.

[0101] By using test data and evaluation criteria, regression analysis can be conducted to obtain the boundary line of the relationship between engine speed and torque. This torque control boundary line matches the vehicle's in-vehicle noise evaluation limit. Within this boundary line, reducing engine torque consistently approaches the optimal fuel consumption point, meaning that using the engine within this range results in optimal NVH and fuel consumption performance for the entire vehicle. Compared to adding active noise cancellation features to suppress cabin noise, this invention is lower in cost and requires no noise frequency band calibration. Applying it to the vehicle's torque control strategy will help the vehicle achieve the required noise performance under different operating conditions and ensure a consistently good driving experience.

[0102] In this invention, through testing and evaluation, within the engine speed range of (1000-4000) rpm, for every 200 rpm increase in engine speed corresponding to the torque of (187.5-375) Nm, the torque increases by 12.5 Nm. This boundary can be used as the NVH control boundary target to adjust the engine torque.

[0103] Step S5: Based on the torque control boundary line, control the vehicle under the corresponding operating condition to adjust the current engine torque.

[0104] Specifically, the torque control boundary line can be stored in the vehicle's ECU as part of the control strategy. In actual operating conditions, the vehicle ECU can use the input torque control boundary line, based on real-time driving needs and SOC conditions, as a reference to determine how to distribute power, including controlling the torque output of the engine and electric motor.

[0105] Step S5 may include:

[0106] Step S51: Obtain the current operating conditions of the vehicle and the current engine torque of the vehicle;

[0107] Step S52: Based on the torque control boundary line, adjust the current engine torque of the vehicle to be less than or equal to the torque data on the torque control boundary line under the current operating conditions.

[0108] In the implemented embodiment, the ECU continuously monitors various sensor data of the vehicle, such as current throttle opening, current vehicle speed, current engine speed, and current engine torque. Under conditions of low SOC, low to medium throttle, and low to medium vehicle speed, torque reduction control can be preset for situations with high torque. The vehicle ECU can choose to reduce the intake air volume and fuel injection volume, thereby reducing the combustion pressure and piston thrust inside the engine, resulting in a decrease in engine torque; alternatively, the vehicle ECU can choose to delay the ignition timing or advance the intake air shut-off timing, thereby reducing the engine torque output; or the vehicle ECU can reduce the engine torque by limiting fuel supply and reducing combustion efficiency; or it can change the operating mode of hybrid vehicles, increasing the participation of the electric motor and reducing the engine torque output. In summary, by controlling the engine torque below the torque control boundary line under the corresponding operating conditions, the noise problem that occurs in some cases can be solved by controlling the torque according to the preset torque boundary.

[0109] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of this application.

[0110] Example 2:

[0111] The present invention also provides an engine torque control system for use in hybrid vehicles, the system comprising:

[0112] The data collection module is used to acquire the operating condition distribution map of the vehicle under different operating conditions. The operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings.

[0113] The torque confirmation module is used to determine the target torque required by the vehicle at a corresponding throttle opening based on multiple sets of engine torques distributed under different throttle openings. The target torque required is the engine limit torque that meets the noise evaluation standard.

[0114] The data analysis module is used to obtain multiple sets of engine torques under different throttle openings and different engine speeds based on the operating condition distribution map.

[0115] The data processing module is used to establish torque control boundary lines under corresponding operating conditions based on multiple sets of target torque requirements.

[0116] The vehicle execution module is used to control the vehicle to adjust the current engine torque under the corresponding operating conditions according to the torque control boundary line.

[0117] In conjunction with the above embodiments, in another embodiment, the data collection module includes:

[0118] The acquisition module is used to acquire the operating condition distribution map of the vehicle under target operating conditions, wherein the target operating conditions include one or more of the following: battery charge is less than or equal to a first threshold, throttle opening is within a first range, and vehicle speed is within a second range.

[0119] In conjunction with the above embodiments, in another embodiment, the torque confirmation module includes:

[0120] The testing module is used to test the calibration noise level corresponding to the calibration torque at the target throttle opening and target speed; wherein, the calibration torque is used to indicate the engine torque when the vehicle is noisy;

[0121] The test submodule is used to test the reference noise level of a reference torque that has a positive or negative difference from the calibration torque, based on the calibration torque.

[0122] A determination submodule is used to evaluate the reference noise level and determine the target torque required by the vehicle at the target throttle opening and target speed.

[0123] In conjunction with the above embodiments, in another embodiment, the determining submodule includes:

[0124] The comparison module is used to compare the reference noise levels of reference torque with positive difference values ​​and reference torque with negative difference values, and to determine whether the corresponding reference noise levels meet the noise evaluation criteria.

[0125] The judgment module is used to determine the limit reference torque that meets the noise evaluation standard as the target required torque, wherein the limit reference torque is the upper limit value of the torque corresponding to meeting the noise evaluation standard.

[0126] In conjunction with the above embodiments, in another embodiment, the data processing module includes:

[0127] The analysis module is used to input multiple sets of the target torque requirements under the corresponding working conditions into the regression model for linear regression analysis to obtain the torque control boundary line.

[0128] Optionally, the vehicle execution module includes:

[0129] The current acquisition module is used to acquire the current operating conditions of the vehicle and determine the current engine torque at the current engine speed of the vehicle.

[0130] The current execution module is used to adjust the current engine torque of the vehicle to be less than or equal to the torque data at the engine speed corresponding to the torque control boundary line under the corresponding operating condition, based on the torque control boundary line.

[0131] Example 3:

[0132] Based on the same inventive concept, one embodiment of this application provides a computer-readable storage medium storing instructions thereon that, when executed by one or more processors, cause the processors to perform the steps of one or more methods as described above.

[0133] Example 4:

[0134] Based on the same inventive concept, one embodiment of this application provides a vehicle that performs the engine torque control method as described in the first aspect of the present invention, and / or is equipped with the engine torque control system as described in the second aspect of the present invention.

[0135] As the vehicle embodiment is substantially similar to the method embodiment and / or system embodiment, it is described in a relatively simple manner. For relevant details, please refer to the descriptions in the system embodiment and / or method embodiment.

[0136] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0137] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus, or computer program products. Therefore, embodiments of this application can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of this application can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0138] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0139] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0140] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0141] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0142] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0143] The above provides a detailed description of the engine torque control method, system, storage medium, and vehicle. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An engine torque control method, characterized in that, Applied to hybrid vehicles, the method includes: Obtain the operating condition distribution map of the vehicle under different operating conditions. The operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings. Based on the operating condition distribution map, multiple sets of engine torques are obtained under different throttle openings and different engine speeds; Based on the multiple sets of engine torques, multiple sets of target required torques for the vehicle are determined, wherein the target required torques are the engine limit torques that meet the noise evaluation standards. Based on the multiple sets of target torque requirements, establish torque control boundary lines under corresponding operating conditions; Based on the torque control boundary line, the vehicle under the corresponding operating condition adjusts its current engine torque.

2. The engine torque control method according to claim 1, characterized in that, The process of obtaining the vehicle's operating condition distribution map under different operating conditions includes: Obtain the operating condition distribution map of the vehicle under target operating conditions, wherein the target operating conditions include one or more of the following: battery charge is less than or equal to a first threshold, throttle opening is within a first range, and vehicle speed is within a second range.

3. The engine torque control method according to claim 1, characterized in that, The determination of the multiple target torque requirements of the vehicle based on multiple sets of engine torques includes: The test measures the calibrated noise level corresponding to the calibrated torque at the target throttle opening and target speed; wherein the calibrated torque is used to indicate the engine torque when the vehicle is noisy. Based on the calibrated torque, the reference noise level of the reference torque that has a positive or negative difference from the calibrated torque is tested; The reference noise level is evaluated to determine the target torque required by the vehicle at the corresponding target throttle opening and target speed.

4. The engine torque control method according to claim 3, characterized in that, The evaluation of the reference noise level, and the determination of the target torque required by the vehicle at the corresponding target throttle opening and target speed, include: By comparing the reference noise levels of reference torques with positive and negative differences, it is determined whether the corresponding reference noise levels meet the noise evaluation criteria. The limit reference torque that meets the noise evaluation standard is determined as the target required torque, and the limit reference torque represents the upper limit value of the torque corresponding to meeting the noise evaluation standard.

5. The engine torque control method according to claim 3, characterized in that, The test items corresponding to the calibrated noise level and / or the reference noise level include at least one of the following: in-vehicle noise, seat rail vibration, active and passive side vibration of the suspension, engine parameters, and electric motor parameters.

6. The engine torque control method according to claim 1, characterized in that, The step of establishing the torque control boundary line under the corresponding operating condition based on multiple sets of target torque requirements includes: The target torque requirements under the corresponding working conditions are input into the regression model for linear regression analysis to obtain the torque control boundary line.

7. The engine torque control method according to claim 1, characterized in that, The step of controlling the vehicle under the corresponding operating condition to adjust the current engine torque according to the torque control boundary line includes: Obtain the current operating conditions of the vehicle and the current engine torque of the vehicle; Based on the torque control boundary line, the current engine torque of the vehicle is adjusted to be less than or equal to the torque data on the torque control boundary line under the current operating conditions.

8. An engine torque control system, characterized in that, The system, applied to hybrid vehicles, includes: The data collection module is used to acquire the operating condition distribution map of the vehicle under different operating conditions. The operating condition map represents the distribution trend of engine torque and engine speed under different throttle openings. The data analysis module is used to obtain multiple sets of engine torques under different throttle openings and different engine speeds based on the operating condition distribution map. The torque confirmation module is used to determine multiple target torque requirements of the vehicle based on multiple sets of engine torques, wherein the target torque requirements are the engine limit torque that meets the noise evaluation standard. The data processing module is used to establish torque control boundary lines under corresponding operating conditions based on multiple sets of target torque requirements. The vehicle execution module is used to control the vehicle to adjust the current engine torque under the corresponding operating conditions according to the torque control boundary line.

9. A computer-readable storage medium, characterized in that, It stores instructions that, when executed by one or more processors, cause the processors to perform the steps of one or more methods as described in claims 1-7.

10. A vehicle, characterized in that, It performs the engine torque control method as described in any one of claims 1-7, and / or is equipped with the engine torque control system as described in claim 8.

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