Control Method, Device and Electronic Device for Flameout Jitter

Abstract

The present application discloses a control method, device and electronic device for flameout jitter. Among them, the method includes: when receiving a flameout request signal of a vehicle, detecting operation state data of the vehicle to obtain a detection result; when the detection result indicates that the operation state data of the vehicle meets a preset condition, determining torque compensation information in the current operation state of the vehicle, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; controlling the output torque of a motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the amplitude of engine jitter. The present application solves the technical problems that the suppression effect is relatively general due to the related technology reducing the jitter of the vehicle based on the throttle, the improvement effect on vehicle jitter is relatively limited, and the comfort is poor.

Description

Technical Field

[0001] The present application relates to the field of vehicle control, and more particularly, to a control method, device, and electronic device for engine-off jitter. Background Art

[0002] In related technologies, generally, the intake throttle loss is increased through throttle control to reduce the jitter of the engine during the engine-off process. However, the above control method often has the technical problems of relatively average jitter suppression effect, relatively limited improvement effect on vehicle jitter, and poor comfort.

[0003] In view of the above problems, no effective solution has been proposed yet. Summary of the Invention

[0004] Embodiments of the present application provide a control method, device, and electronic device for engine-off jitter, so as to at least solve the technical problems of relatively average suppression effect, relatively limited improvement effect on vehicle jitter, and poor comfort due to the related technology of reducing vehicle jitter based on the throttle. [[ID=I7]]

[0005] According to one aspect of the embodiments of the present application, a control method for engine-off jitter is provided, including: detecting operation state data of a vehicle when a vehicle engine-off request signal is received to obtain a detection result; determining torque compensation information of the vehicle in the current operation state when the detection result indicates that the operation state data of the vehicle meets a preset condition, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; and controlling the output torque of an electric motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the jitter amplitude of the engine.

[0006] Optionally, determining the torque compensation information of the vehicle in the current operation state includes: obtaining the real-time rotational speed of the engine; determining the moment when the predicted value of the real-time rotational speed is greater than a first threshold as the intervention moment of the output torque of the electric motor; and determining the moment when the predicted value of the real-time rotational speed is less than a second threshold as the withdrawal moment of the output torque of the electric motor, where the first threshold is greater than the second threshold.

[0007] Optionally, controlling the output torque of the electric motor in the vehicle according to the torque compensation information includes: determining the time period between the intervention moment and the withdrawal moment as the target time period; obtaining the change information of the torque; and controlling the output torque of the electric motor to be output based on the change information within the target time period.

[0008] Optionally, obtaining the change information of the torque includes: obtaining the vibration acceleration of the vehicle and the noise intensity inside the vehicle; and determining the change information according to the vibration acceleration and the noise intensity, where both the vibration acceleration and the noise intensity are negatively correlated with the change information.

[0009] Optionally, control the output torque of the motor to be output based on the change information within a target time period, including: determining a first time period during which the vibration acceleration continuously belongs to a first preset range; determining a second time period during which the noise intensity continuously belongs to a second preset range; determining an overlapping time period between the first time period and the second time period; determining any moment in the overlapping time period as a critical point of the output torque, where the output torque is the largest at the critical point; controlling the output torque to gradually increase based on the change information before the critical point and gradually decrease based on the change information after the critical point until it becomes zero.

[0010] Optionally, before controlling the output torque of the motor according to the torque compensation information, the method further includes: detecting the actual rotational speed of the engine at the current moment; determining the friction loss level of the engine, and determining the magnitude of the output torque according to the actual rotational speed and the friction loss level, where the actual rotational speed is positively correlated with the magnitude of the output torque.

[0011] Optionally, determining the friction loss level of the engine includes: obtaining the water temperature of the engine; in the case where the water temperature is less than a first temperature threshold, determining the friction loss level as a first loss level, where the first friction loss level is used to indicate that the friction loss of the engine cannot be ignored; in the case where the water temperature is greater than a second temperature threshold, determining the friction loss level as a second loss level, where the second temperature threshold is greater than the first temperature threshold, and the friction loss parameter value of the second loss level is less than the friction loss parameter value corresponding to the first friction loss level.

[0012] Optionally, determining the magnitude of the output torque according to the actual rotational speed and the friction loss level includes: in the case where the friction loss level is determined to be the first loss level, obtaining the friction loss parameter value of the engine; determining a first weight value corresponding to the friction loss and a second weight value corresponding to the actual rotational speed; obtaining the magnitude of the output torque according to the friction loss parameter value, the actual rotational speed, the first weight value, and the second weight value.

[0013] According to another aspect of the embodiments of the present application, there is also provided a device for controlling engine-off jitter, including: a detection module, configured to detect the operating state data of the vehicle when receiving a vehicle engine-off request signal, and obtain a detection result; a determination module, configured to determine torque compensation information of the vehicle in the current operating state when the detection result indicates that the operating state data of the vehicle meets a preset condition, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; a control module, configured to control the output torque of the motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the jitter amplitude of the engine.

[0014] According to another aspect of the embodiments of the present application, there is also provided a non-volatile storage medium, where the storage medium includes a stored program, and when the program runs, it controls the device where the storage medium is located to execute any one of the methods for controlling engine-off jitter.

[0015] According to another aspect of the embodiments of the present application, an electronic device is further provided, including: a processor; a memory for storing instructions executable by the processor; wherein the processor is configured to execute the instructions to implement any one of the control methods for engine shutdown jitter.

[0016] In the embodiments of the present application, by adopting the method of outputting a resistance torque by the motor, when receiving a vehicle engine shutdown request signal, the running state data of the vehicle is detected to obtain a detection result, and when the detection result indicates that the running state data of the vehicle meets a preset condition, the torque compensation information in the current running state of the vehicle is determined, and the output torque of the motor is controlled based on the torque compensation information, so as to achieve the purpose of suppressing engine jitter based on the resistance torque output by the vehicle motor, and also determine the intervention and withdrawal moments of the torque that needs to be output by the motor, control the output torque of the motor to intervene at the intervention moment and withdraw at the withdrawal moment, thereby realizing the technical effects of improving the jitter suppression effect, enhancing vehicle comfort, and effectively reducing engine shutdown vibration, and further solving the technical problems that the suppression effect of the related technology based on the throttle to slow down the vehicle jitter is relatively general, the improvement effect on vehicle jitter is relatively limited, and the comfort is poor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The schematic embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0018] Figure 1 is a schematic flowchart of an optional control method for engine shutdown jitter according to an embodiment of the present application;

[0019] Figure 2 is a schematic diagram of the vibration acceleration and rotational speed performance after engine shutdown in an exemplary embodiment of the present application;

[0020] Figure 3 is a flowchart of a control strategy for reducing the engine shutdown process in an exemplary embodiment of the present application;

[0021] Figure 4 is a schematic diagram of the change in the gear train transmission ratio during the engine shutdown process in an exemplary embodiment of the present application;

[0022] Figure 5 is a schematic curve diagram of a 48V motor torque control strategy generated according to test data in an exemplary embodiment of the present application;

[0023] Figure 6 is a schematic diagram of the change in the output torque of a 48V motor in an exemplary embodiment of the present application;

[0024] Figure 7 It is a schematic diagram of the engine speed performance before and after optimization in an exemplary embodiment of the present application;

[0025] Figure 8 It is a schematic diagram of the vibration acceleration signal performance before and after optimization in an exemplary embodiment of the present application;

[0026] Figure 9 It is a schematic structural diagram of an optional control device for flameout jitter in an embodiment of the present application. Detailed implementation manners

[0027] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described here can be implemented in an order different from those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0029] According to an embodiment of the present application, an embodiment of a control method for flameout jitter is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described here can be executed in an order different from that here.

[0030] To facilitate those skilled in the art to better understand the related embodiments of the present application, the following is a glossary of technical terms or some nouns that may be involved in the embodiments of the present application:

[0031] Automotive NVH, where NVH stands for Noise, Vibration, and Harshness respectively. NVH is a comprehensive issue that measures the manufacturing quality of automobiles, and it gives the most direct and obvious impression to automobile users.

[0032] A vibration sensor is also called a vibration meter or vibrometer. Its function is to accurately receive the mechanical vibration quantity (displacement, velocity, or acceleration) of the measured object and convert this mechanical quantity into an electrical signal (current or voltage) for output or display. From the perspective of energy, the vibration sensor realizes the conversion from mechanical energy to electrical energy. Substantially, it can be regarded as a transducer.

[0033] A sound level meter consists of a microphone, a preamplifier, a signal processor, and a display screen. The microphone converts the sound signal into an equivalent electrical signal. The most suitable type of microphone for a sound level meter is a condenser microphone, which has high accuracy, stability, and reliability. The electrical signal generated by the microphone is very weak, so it is first amplified by the preamplifier and then processed by the main processor.

[0034] Figure 1 It is a schematic flowchart of the control method for engine shutdown jitter according to an embodiment of the present application. As Figure 1 shown, the method includes the following steps:

[0035] Step S102: When receiving a vehicle engine shutdown request signal, detect the vehicle's operating state data to obtain a detection result.

[0036] In the technical solution provided in step S102 of the present application, by detecting the vehicle's operating state data when receiving a vehicle engine shutdown request signal to obtain a detection result, it should be noted that the vehicle's motion state data includes but is not limited to: vehicle speed, engine speed, water temperature, gear position, accelerator pedal, etc.

[0037] Step S104: When the detection result indicates that the vehicle's operating state data meets a preset condition, determine the torque compensation information for the vehicle in the current operating state, where the torque compensation information is at least used to indicate the moments of torque intervention and torque withdrawal.

[0038] In the technical solution provided in step S104 of the present application, when the detection result indicates that the vehicle's operating state data meets a preset condition, the torque compensation information for the vehicle in the current state can be determined, where the torque compensation information is at least used for the moments of torque intervention and withdrawal, that is, through the technical solution provided in step S104, the moments of torque intervention and withdrawal to be compensated can be determined, and intervention or withdrawal can be performed at the corresponding moments to reduce the engine jitter. It should be noted that the intervened torque can be the resistance torque output by the 48V motor system.

[0039] Optionally, the determination of whether the operating state data of the vehicle meets the preset conditions may include multiple aspects. Specifically, it may include the vehicle level, the engine level, and the system level, etc., and the state data of multiple aspects.

[0040] Specifically: 1) At the vehicle level: ① Before the engine is turned off, the vehicle speed is less than 0.5 km / h, the gear is in the parking gear or the first gear of the driving gear, and the driver's required torque is 0; ② The start-stop shutdown condition is activated or the vehicle is in the power-off state;

[0041] 2) At the engine level: ① The engine speed is less than 1000 r / min; ② The water temperature limit is -30 to 120 °C; ③ The engine is at the idle speed.

[0042] 3) At the 48V system level: ① The motor speed is less than 2800 r / min; ② The battery voltage is 30 to 56V; ③ The battery SOC is 20% to 80%; ④ The battery temperature is -30 to 65 °C; ⑤ There is no 48V system-related fault; ⑥ It does not exceed the predicted maximum torque of the motor and the maximum allowable temperature of the motor; among which the engine speed, throttle opening, driver's required torque, water temperature, idle flag, key switch state, and start-stop state signal are sourced from the ECU and output; among which the vehicle speed is sourced from the ESP (Electronic Stability Program control unit); the gear is sourced from the TCU (Transmission Control Unit); the 48V motor speed, battery temperature, voltage and other signals are sourced from the MCU (Motor Control Unit), BMS (Battery Management System) respectively; and all are output through the CAN bus. Among them, for the data range at the 48V system level, it is sourced from the big data statistical results and the input of relevant component characteristics, and to ensure to the greatest extent that this function can be normally activated as long as the engine is turned off under any working condition.

[0043] Step S106, control the output torque of the motor in the vehicle according to the torque compensation information, wherein the output torque is used to reduce the vibration amplitude of the engine.

[0044] Through the technical solutions of the above steps S102 to S106, by adopting the method of the motor outputting a resistance torque, when receiving the vehicle flameout request signal, the running state data of the vehicle is detected to obtain a detection result, and when the detection result indicates that the running state data of the vehicle meets the preset conditions, the torque compensation information in the current running state of the vehicle is determined, and the output torque of the motor is controlled based on the torque compensation information, achieving the purpose of suppressing engine jitter based on the resistance torque output by the vehicle motor, and also determining the intervention and withdrawal moments of the torque that needs to be output by the motor, controlling the output torque of the motor to intervene at the intervention moment and withdraw at the withdrawal moment, thereby realizing the technical effects of improving the jitter suppression effect, enhancing vehicle comfort, and effectively reducing flameout vibration, and further solving the technical problems that the jitter suppression effect of the related technology based on the throttle is relatively general, the improvement effect on vehicle jitter is relatively limited, and the comfort is poor.

[0045] As an optional implementation manner, determining the torque compensation information in the current running state of the vehicle can be achieved through the following steps: obtaining the real-time speed of the engine; determining the moment when the predicted value of the real-time speed is greater than the first threshold as the intervention moment of the output torque of the motor; determining the moment when the predicted value of the real-time speed is less than the second threshold as the withdrawal moment of the output torque of the motor, where the first threshold is greater than the second threshold.

[0046] In some embodiments of the present application, controlling the output torque of the motor in the vehicle according to the torque compensation information includes: determining the time period between the intervention moment and the withdrawal moment as the target time period; obtaining the change information of the torque; controlling the output torque of the motor to be output based on the change information within the target time period.

[0047] Specifically, obtaining the change information of the torque can be achieved through the following steps: obtaining the vibration acceleration of the vehicle and the noise intensity inside the vehicle; determining the change information according to the vibration acceleration and the noise intensity, where both the vibration acceleration and the noise intensity are negatively correlated with the change information.

[0048] Optionally, the above vibration acceleration can be determined by the mechanical signal collected by the vibration sensor, and the above noise intensity can be determined by the sound signal collected by the acoustic sensor, such as a sound level meter. It should be noted that the above change information includes, but is not limited to, the change gradient of the torque. It can be understood that the greater the vibration acceleration, the faster and more timely the engine vibration needs to be reduced, and the faster the required change gradient. Similarly, the greater the noise intensity, the faster and more timely the engine vibration needs to be reduced, so the required change gradient is also faster.

[0049] In some embodiments of the present application, controlling the output torque of the motor to be output based on the change information within the target period can be achieved through the following steps. Specifically, a first period during which the vibration acceleration continuously belongs to the first preset range can be determined; a second period during which the noise intensity continuously belongs to the second preset range can be determined; an overlapping period between the first period and the second period can be determined; any moment within the overlapping period can be determined as the critical point of the output torque, where the output torque is the largest at the critical point; the output torque can be controlled to gradually increase based on the change information before the critical point and gradually decrease based on the change information after the critical point until it becomes zero. By determining the critical point, the transition of the entire adjustment process can be made relatively smooth, which will not cause the output torque of the motor to be too large and result in negative effects, nor will it make the time required for the entire adjustment process too long due to the small output torque of the motor, affecting the user's comfort experience.

[0050] As an alternative implementation, before controlling the output torque of the motor according to the torque compensation information, the actual speed of the vehicle engine at the current moment can also be detected; the friction loss level of the engine can be determined, and the magnitude of the output torque can be determined according to the actual speed and the friction loss level, where the actual speed is positively correlated with the magnitude of the output torque. The magnitude of the output torque of the motor can be obtained through the actual speed and the friction loss level.

[0051] Specifically, determining the friction loss level of the engine can be achieved through the following steps: obtaining the water temperature of the engine; in the case where the water temperature is less than the first temperature threshold, determining that the friction loss level is the first loss level, where the first friction loss level is used to indicate that the friction loss of the engine cannot be ignored; in the case where the water temperature is greater than the second temperature threshold, determining that the friction loss level is the second loss level, where the second temperature threshold is greater than the first temperature threshold, and the friction loss parameter value of the second loss level is less than the friction loss parameter value corresponding to the first friction loss level. For example, the first temperature threshold can be set to 20 °C, and when the current water temperature is 15 °C, the friction loss of the engine needs to be determined; for example, the second temperature threshold can be set to 60 °C, and when the current water temperature is 62 °C, the friction loss of the engine can be ignored.

[0052] In some alternative embodiments of the present application, determining the magnitude of the output torque according to the actual speed and the friction loss level includes: in the case where the friction loss level is determined to be the first loss level, obtaining the friction loss parameter value of the engine; determining the first weight value corresponding to the friction loss and the second weight value corresponding to the actual speed; obtaining the magnitude of the output torque according to the friction loss parameter value, the actual speed, the first weight value, and the second weight value. It should be noted that the product of the friction loss parameter and the first weight value can be determined first, then the product of the actual speed and the second weight value can be determined, and then the two products are added to obtain the sum value, and the magnitude of the output torque is determined according to the sum value.

[0053] The above technical solution will be further introduced by way of example in conjunction with an exemplary embodiment.

[0054] When the engine shuts off, although the engine no longer ignites and injects fuel, the compressed high-pressure gas still does work on the piston to generate thrust. The more fresh air inhaled during the intake stroke, the greater the expansion work generated during the power stroke. Due to continuous intake and exhaust, gas compression and expansion, that is, periodic inertial forces and gas compression pressures continuously generate excitations. Such excitations will cause the dual-mass flywheel to resonate, resulting in a "clicking" aftersound when shutting off the engine, affecting comfort.

[0055] To solve the above technical problems, an engine shutdown control method based on a 48V system, namely a shutdown assistance function, is adopted in this embodiment. By optimizing the 48V torque control strategy for shutdown, it will reduce shutdown jitter, make the shutdown process smoother, and provide a more comfortable subjective feeling; at the same time, a small amount of kinetic energy can be recovered when the engine shuts off. Specifically, the steps are as follows:

[0056] Step A: Activate the shutdown assistance requirement according to the vehicle, engine, and 48V system.

[0057] 1. The ECU identifies the engine shutdown condition and obtains the vehicle's state data (vehicle speed, engine speed, water temperature, gear position, accelerator pedal, 48V system working status, etc.). Since each controller has a certain post-operation time after shutdown, these vehicle data can be conveniently obtained; 2. Determine whether the state data meets the preset conditions. The following conditions 1-3 need to be fully met (the data can be calibrated) to activate the shutdown assistance function. The specific preset conditions have been described above and will not be elaborated here.

[0058] Step B: Select relevant core parameters inside the ECU and MCU based on the analysis results of test data to establish a control model. The specific selection method is as follows:

[0059] 1. Conduct in-depth test analysis on the vibration characteristics during the shutdown process under idle conditions. A vibration acceleration sensor can be installed at the seat rail during the test. Measuring the vibration at the seat rail inside the vehicle can represent the vibration directly felt by the human body. In addition, since the engine speed largely reflects the excitation characteristics of the engine on the whole vehicle, the instantaneous speed of the engine crankshaft is synchronously collected during this process to judge the excitation level of the engine. At the same time, the noise signal can be collected through an acoustic sensor installed inside the vehicle to evaluate the idle shutdown jitter level.

[0060] 2. Figure 2 This is a schematic diagram showing the vibration acceleration and speed performance after shutdown in this embodiment, as Figure 2As shown in the figure, after the engine is turned off, as the engine speed decreases, the vibration acceleration signal gradually decreases. In the second half of the engine turning off, the vibration amplitude suddenly increases, causing strong vibration. At this time, the vibration acceleration voltage amplitude reaches 4V, and the human ear can clearly hear a "clicking" sound, which gives a very poor subjective feeling.

[0061] 3. Through the analysis of the above data, it can be determined that the peak position of the vibration acceleration has a good correspondence with the speed fluctuation. Under the same stroke (which can be considered as a 180-degree crankshaft angle), the engine works reciprocatingly in four strokes. In the early stage, the interval between each cylinder is short and the speed is relatively stable. The engine speed gradually decreases due to internal friction loss. In the later stage, the speed fluctuates severely.

[0062] 4. Based on the above analysis results, a targeted control strategy can be formulated to control the 48V motor intervention time, torque size, torque gradient, torque withdrawal time, and 48V motor protection functions during the shutdown process. According to different acceleration performances, data is continuously optimized to reduce the jitter during the shutdown process. Figure 3 Flowchart of the control strategy to reduce the flameout process, such as Figure 3 As shown, the process mainly includes the following steps:

[0063] 1) The ECU sends the shutdown request to the MCU, and the MCU determines whether to activate the shutdown assist function based on the conditions listed in Article 2 above.

[0064] 2) The ECU issues various control commands to activate the stop assist function. The specific parameters are set as follows: When the 48V motor torque intervenes, it is necessary to determine whether the engine speed or the motor speed is used as the enabling condition. Through comparative analysis of test data, the engine speed is selected as the enabling condition for the following reasons:

[0065] During the shutdown process, due to the elastic damping of the wheel belt and tensioner, the transmission ratio is not a constant value. Through experiments, it is found that the lower the speed, the greater the change in the transmission ratio. Figure 4 This is a schematic diagram of the gear train transmission ratio change during the flameout process, such as Figure 4 It can be seen that the transmission ratio is always changing and is not a constant value. In addition, the signal can be accessed through the CAN bus.

[0066] Figure 5 The 48V motor torque control strategy is generated based on the above test data, such as Figure 5As shown in the figure, in order to cover the entire speed reduction process and achieve 48V torque intervention as soon as possible, the A point (i.e., the intervention moment) is set to 700 r / min, and the anti-bounce time is increased by 0.1 s. From the current data, it is equivalent to 150 ms after the engine stalls, and the motor starts to intervene. At the same time, during this period, the motor torque is controlled to be near 0 (to avoid the 48V power generation difference caused by the 12V load). In this way, at the initial point of the 48V motor intervention, the current motor torque can be guaranteed to be at the same level, more accurately controlling the torque gradient and ensuring the consistency of each shutdown state. The B point (withdrawal moment) is set to 200 - 250 r / min when a large value appears in the vibration acceleration signal. At the moment when the 48V motor torque withdraws, according to the above intervention moment, it is determined that the engine speed is less than the minimum speed of 250 r / min and delayed by 0.1 s, and greater than the maximum speed of 700 r / min. In addition, during the idle shutdown process, if a start activation occurs, the system will immediately interrupt the 48V torque intervention. At this time, even if the engine speed has not reached below 250 r / min, it will quickly switch to the positive torque demand for normal starting, greatly ensuring the normal starting demand of users.

[0067] It should be noted that Figure 5 the torque at point C in the figure is the torque corresponding to the critical point. This critical point torque can be the maximum torque that the motor needs to output, and can be calculated based on the 48V battery SOC, voltage, temperature, 12V load conditions, etc., to represent the current maximum capacity of the motor. Since the water temperature is different, it will affect the internal torque loss of the engine. Therefore, when the engine is cold, due to the large internal friction loss of the engine, a slightly smaller 48V motor negative torque can be used. During the warm-up process, since the internal friction loss of the engine decreases, the motor torque can be increased. When the temperature is 60°C and above, since the engine friction loss has remained unchanged, the 48V motor torque can maintain a relatively large value, but it is also necessary to avoid reverse rotation due to excessive motor torque in the later stage of engine shutdown. In this example, the torque at point C can obtain the friction loss at the same speed during the process of the 48V motor dragging the engine to start in reverse (the same as the friction loss during the shutdown process). The friction torque can be measured by the 48V motor. Through multiple vehicles, big data analysis, and multiple optimizations, the motor torque is finally determined to be -23 Nm. Figure 6 is a schematic diagram of the output torque change of the 48V motor, as shown in Figure 6 . In addition, the combined state of the transmission chain needs to be considered. For N - gear and D - gear shutdowns (idle start - stop), a 48V motor torque correction coefficient needs to be added. This coefficient is related to the transmission oil temperature. To further achieve lean production, the shutdown process control can be made more consistent, avoiding the subjective feeling differences of users during the N - gear and D - gear shutdown processes.

[0068] Calculate the 48V motor torque change gradient, that is Figure 5Among them, the gradient when the torque intervenes from point A to point C, that is, after determining the maximum torque, if the adjustment is too fast, the torque will drop too fast, resulting in a strong sense of drag and abruptness, especially during idle stop. Therefore, it is also necessary to determine the torque change gradient.

[0069] It is easy to notice that from point C to point B belongs to the period when the 48V motor torque starts to prepare to withdraw and completes the withdrawal at point B. Through multiple tests, it is found that the 48V motor torque no longer needs to be maintained continuously, and a long-time negative torque will cause the motor torque to withdraw too late, resulting in the situation of motor or engine reverse, and it will also cause certain wear to the front-end gear train (belt, tensioner, etc.). Therefore, for the torque change gradient from C to B, not only appropriate data needs to be selected, but also sufficient durability verification should be carried out. After optimization, the torque change rate from A to B is determined to be 200 Nm / s, and the torque change rate from C to B is 280 Nm / s (engine end) in this embodiment.

[0070] Step C: According to the above calibration strategy, compare the front and rear effects: After optimizing the above strategy and data, compare the engine speed fluctuations before and after the engine shutdown process. Figure 7 It is a schematic diagram of the engine speed performance before and after optimization. From Figure 7 it can be seen that in the original scheme (without 48V torque intervention), there were 5 relatively serious sawtooth jitters during the process of the engine speed dropping below 500 r / min. The closer it was to 0 speed, the more serious the jitter became, and the amplitude of the speed jitter reached 300 r / min / s. While using the 48V torque scheme of this application, the engine speed drops rapidly, and the speed jitter is very small during the whole process and can basically be ignored.

[0071] Figure 8 It is a schematic diagram of the vibration acceleration signal performance before and after optimization. As Figure 8 shown, by comparing the vibration acceleration signal at the seat rail, it can be known that when using the 48V torque intervention scheme, under this working condition, the amplitude of the vibration acceleration signal is reduced by more than 80%, and obvious improvement is obtained.

[0072] At the same time, in some other embodiments, this scheme has successfully completed a large number of durability verifications such as start-stop and regional adaptability. Through the remote data acquisition system, test data of multiple sample vehicles are obtained to determine that the data performance is consistent with the control strategy performance, and the improvement effect of the shutdown jitter does not deteriorate as the vehicle mileage increases.

[0073] Figure 9 It is a schematic structural diagram of a control device for shutdown jitter according to an embodiment of the present application. As Figure 9 shown, this device includes:

[0074] A detection module 90, configured to detect the operating state data of the vehicle and obtain a detection result when receiving a shutdown request signal of the vehicle;

[0075] A determination module 92, configured to determine torque compensation information of the vehicle in the current operating state when the detection result indicates that the operating state data of the vehicle meets a preset condition, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal.

[0076] A control module 94, configured to control the output torque of the motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the jitter amplitude of the engine.

[0077] In the control device for engine-off jitter, a detection module 90 is configured to detect the operating state data of the vehicle and obtain a detection result when receiving an engine-off request signal of the vehicle; a determination module 92 is configured to determine torque compensation information of the vehicle in the current operating state when the detection result indicates that the operating state data of the vehicle meets a preset condition, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; a control module 94 is configured to control the output torque of the motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the jitter amplitude of the engine, achieving the purpose of suppressing engine jitter based on the resistance torque output by the motor of the vehicle, and also determining the moments of torque intervention and withdrawal required for the motor to output torque, controlling the output torque of the motor to intervene at the intervention moment and withdraw at the withdrawal moment, thereby realizing the technical effects of improving the jitter suppression effect, enhancing the vehicle comfort, and effectively reducing the engine-off vibration, and further solving the technical problems that the suppression effect is relatively average when the related technology reduces the jitter of the vehicle based on the throttle, the improvement effect on the vehicle jitter is relatively limited, and the comfort is poor.

[0078] According to another aspect of the embodiments of the present application, there is also provided a non-volatile storage medium, where the storage medium includes a stored program, and when the program runs, it controls the device where the storage medium is located to execute any control method for engine-off jitter.

[0079] According to another aspect of the embodiments of the present application, there is also provided an electronic device, including: a processor; a memory for storing instructions executable by the processor; where the processor is configured to execute the instructions to implement any control method for engine-off jitter.

[0080] Specifically, the above storage medium is used to store program instructions with the following functions to implement the following functions:

[0081] When a vehicle shutdown request signal is received, the operating state data of the vehicle is detected to obtain a detection result; when the detection result indicates that the operating state data of the vehicle meets a preset condition, torque compensation information for the vehicle in the current operating state is determined, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; the output torque of the motor in the vehicle is controlled according to the torque compensation information, where the output torque is used to reduce the amplitude of engine jitter.

[0082] In the related embodiments of the present application, by adopting the method of outputting a resistance torque by the motor, when a vehicle shutdown request signal is received, the operating state data of the vehicle is detected to obtain a detection result, and when the detection result indicates that the operating state data of the vehicle meets a preset condition, torque compensation information for the vehicle in the current operating state is determined, and the output torque of the motor is controlled based on the torque compensation information, achieving the purpose of suppressing engine jitter based on the resistance torque output by the vehicle's motor. Moreover, the moments of torque intervention and withdrawal required for the motor to output torque are also determined, and the output torque of the motor is controlled to intervene at the intervention moment and withdraw at the withdrawal moment, thereby realizing the technical effects of improving the jitter suppression effect, enhancing vehicle comfort, and effectively reducing shutdown vibration, and further solving the technical problems that the suppression effect is relatively average when the related technology reduces vehicle jitter based on the throttle, the improvement effect on vehicle jitter is relatively limited, and the comfort is poor.

[0083] The serial numbers of the above embodiments of the present application are only for description and do not represent the superiority or inferiority of the embodiments.

[0084] In the above embodiments of the present application, the descriptions of each embodiment have their own focuses. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0085] In several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of the units can be a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the units or modules can be in an electrical or other form.

[0086] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0087] In addition, each functional unit in various embodiments of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0088] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, may be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), mobile hard disks, magnetic disks, or optical discs that can store program codes.

[0089] The above are only the preferred embodiments of the present application. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present application, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A control method for flameout jitter, characterized in that, Including: When receiving a vehicle flameout request signal, detecting the operating state data of the vehicle to obtain a detection result; When the detection result indicates that the operating state data of the vehicle meets a preset condition, determining torque compensation information of the vehicle in the current operating state, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; Controlling the output torque of the motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the jitter amplitude of the engine; Among them, determining the torque compensation information of the vehicle in the current operating state includes: obtaining the real-time speed of the engine; determining the moment when the predicted value of the real-time speed is greater than a first threshold as the intervention moment of the output torque of the motor; determining the moment when the predicted value of the real-time speed is less than a second threshold as the withdrawal moment of the output torque of the motor, where the first threshold is greater than the second threshold; Controlling the output torque of the motor in the vehicle according to the torque compensation information includes: determining the period between the intervention moment and the withdrawal moment as the target period; obtaining the change information of the torque, including: Obtaining the vibration acceleration of the vehicle and the noise intensity inside the vehicle; determining the change information according to the vibration acceleration and the noise intensity, where both the vibration acceleration and the noise intensity are positively correlated with the change information; controlling the output torque of the motor to be output based on the change information within the target period.

2. The method according to claim 1, wherein Controlling the output torque of the motor to be output based on the change information within the target period includes: Determining a first period during which the vibration acceleration continuously belongs to a first preset range; Determining a second period during which the noise intensity continuously belongs to a second preset range; Determining the overlapping period of the first period and the second period; Determining any moment in the overlapping period as the critical point of the output torque, where the output torque is the largest at the critical point; Controlling the output torque to gradually increase based on the change information before the critical point and gradually decrease to zero based on the change information after the critical point.

3. The method according to claim 1, characterized in that, Before controlling the output torque of the motor according to the torque compensation information, the method further includes: Detecting the actual speed of the engine at the current moment; Determining the friction loss level of the engine, and determining the magnitude of the output torque according to the actual speed and the friction loss level, where the actual speed is positively correlated with the magnitude of the output torque.

4. The method according to claim 3, wherein Determining the friction loss level of the engine includes: Obtaining the water temperature of the engine; When the water temperature is less than a first temperature threshold, determining the friction loss level as a first loss level, where the first loss level is used to indicate that the friction loss of the engine cannot be ignored; When the water temperature is greater than a second temperature threshold, determine that the friction loss level is a second loss level, where the second temperature threshold is greater than the first temperature threshold, and the friction loss parameter value of the second loss level is less than the friction loss parameter value corresponding to the first loss level.

5. The method according to claim 4, wherein Determine the magnitude of the output torque according to the actual rotational speed and the friction loss level, including: When determining that the friction loss level is the first loss level, obtain the friction loss parameter value of the engine; Determine a first weight value corresponding to the friction loss and a second weight value corresponding to the actual rotational speed; Obtain the magnitude of the output torque according to the friction loss parameter value, the actual rotational speed, the first weight value, and the second weight value.

6. A control device for flameout jitter, characterized in that, Including: A detection module, configured to detect the operating state data of the vehicle when receiving a vehicle flameout request signal, and obtain a detection result; A determination module, configured to determine torque compensation information of the vehicle in the current operating state when the detection result indicates that the operating state data of the vehicle meets a preset condition, where the torque compensation information is at least used to represent the moments of torque intervention and torque withdrawal; A control module, configured to control the output torque of the motor in the vehicle according to the torque compensation information, where the output torque is used to reduce the jitter amplitude of the engine; Wherein, the determination module is further configured to obtain the real-time rotational speed of the engine; determine the moment when the predicted value of the real-time rotational speed is greater than a first threshold as the moment of torque intervention of the output torque of the motor; determine the moment when the predicted value of the real-time rotational speed is less than a second threshold as the moment of torque withdrawal of the output torque of the motor, where the first threshold is greater than the second threshold; The control module is further configured to determine a target period between the moment of intervention and the moment of withdrawal; obtain the change information of the torque, including: obtaining the vibration acceleration of the vehicle and the noise intensity inside the vehicle; determining the change information according to the vibration acceleration and the noise intensity, where both the vibration acceleration and the noise intensity are positively correlated with the change information; control the output torque of the motor to be output based on the change information within the target period.

7. A non-volatile storage medium, characterized in that, The storage medium includes a stored program, where when the program runs, it controls the device where the storage medium is located to execute the method for controlling flameout jitter according to any one of claims 1 to 5.

8. An electronic device, characterized in that, Including: A processor; A memory for storing instructions executable by the processor; Wherein, the processor is configured to execute the instructions to implement the method for controlling flameout jitter according to any one of claims 1 to 5.

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