Method for controlling intermittent oscillation of a vehicle, control device and storage medium

Abstract

The application discloses a kind of intermittent shaking control method, control device and storage medium of preventing car.The method comprises: obtaining the current working frequency of carbon tank solenoid valve, engine measured data and suspension system measured data;According to the current working frequency of carbon tank solenoid valve and engine measured data, obtain engine excitation time domain data;Engine excitation time domain data is processed in time domain to frequency domain, and engine excitation frequency domain data is obtained.Based on engine excitation time domain data and suspension system measured data, modeling is carried out, and suspension system rigid body mode is obtained;According to engine excitation frequency domain data and suspension system rigid body mode, execute the control strategy of preventing car intermittent shaking.The method can utilize the data model between the working frequency based on carbon tank solenoid valve and engine excitation, engine excitation frequency domain data and suspension system rigid body mode constructed and car intermittent shaking, to avoid the risk of car intermittent shaking, can improve the efficiency of calibration and reduce cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of automobile noise control technology, and particularly relates to a method for preventing intermittent shaking of an automobile, a control device and a storage medium. BACKGROUND

[0002] Intermittent shaking of an automobile under an idle condition is one of important contents of development of an NVH performance of the automobile. The idle condition refers to a no-load operation state of an engine. The intermittent shaking of the automobile refers to a vibration phenomenon that makes a human body feel uncomfortable when a modulation phenomenon is amplified by a modal of the automobile and subsystems thereof.

[0003] There are many influencing factors of the intermittent shaking of the automobile under the idle condition, mainly including an idle speed, a rigid body modal of a suspension system of a power assembly and a working frequency of a carbon canister electromagnetic valve. The existing control of the intermittent shaking of the automobile is mainly based on real vehicle tuning. According to a measured or calculated rigid body modal of the suspension system, an appropriate working frequency of the carbon canister is selected, and a degree of the intermittent shaking of the automobile is determined based on a measured vibration signal of the automobile. The control process of the intermittent shaking of the automobile by using the real vehicle tuning method has a large amount of tuning work, low tuning efficiency and high cost. SUMMARY

[0004] Embodiments of the present application provide a method for preventing intermittent shaking of an automobile, a control device and a storage medium to solve the problems of low efficiency and high cost in the existing control process of the intermittent shaking of the automobile by using the real vehicle tuning method.

[0005] A method for preventing intermittent shaking of an automobile, comprising:

[0006] obtaining a current working frequency of a carbon canister electromagnetic valve, engine measured data and suspension system measured data;

[0007] obtaining engine excitation time domain data according to the current working frequency of the carbon canister electromagnetic valve and the engine measured data;

[0008] performing time domain to frequency domain processing on the engine excitation time domain data to obtain engine excitation frequency domain data.

[0009] performing modeling based on the engine excitation time domain data and the suspension system measured data to obtain a rigid body modal of the suspension system;

[0010] executing a control strategy for preventing the intermittent shaking of the automobile according to the engine excitation frequency domain data and the rigid body modal of the suspension system.

[0011] Preferably, the obtaining of the engine excitation time domain data according to the current working frequency of the carbon canister electromagnetic valve and the engine measured data comprises:

[0012] According to the current working frequency of the carbon can electromagnetic valve and engine measured data, engine in-cylinder pressure is obtained;

[0013] According to the engine in-cylinder pressure and the engine measured data, engine excitation time domain data is obtained.

[0014] Preferably, the engine measured data includes engine idle speed;

[0015] According to the current working frequency of the carbon can electromagnetic valve and engine measured data, engine in-cylinder pressure is obtained, including:

[0016] According to the current working frequency of the carbon can electromagnetic valve and the engine idle speed, engine in-cylinder pressure is obtained.

[0017] Preferably, according to the engine in-cylinder pressure and the engine measured data, engine excitation time domain data is obtained, including:

[0018] The engine measured data is calculated by using a mass force formula to obtain a mass force;

[0019] The engine measured data is calculated by using a mass torque formula to obtain a mass torque;

[0020] The engine in-cylinder pressure and the engine measured data are calculated by using a gas torque formula to obtain a gas torque;

[0021] The engine excitation time domain data includes the mass force, the mass torque and the gas torque.

[0022] Preferably, the modeling is based on the engine excitation time domain data and the measured data of the suspension system to obtain the rigid body modal of the suspension system, including:

[0023] The modeling is based on the engine excitation time domain data and the measured data of the suspension system to obtain an excitation kinematics relationship;

[0024] The excitation kinematics relationship is subjected to fast Fourier transform to obtain a frequency domain eigenvalue corresponding to the excitation kinematics relationship, and the frequency domain eigenvalue is used to determine the rigid body modal of the suspension system.

[0025] Preferably, according to the engine excitation frequency domain data and the rigid body modal of the suspension system, an automobile intermittent jitter control strategy is executed, including:

[0026] According to the engine excitation frequency domain data and the rigid body modal of the suspension system, it is judged whether the modal coupling condition is met;

[0027] If the modal coupling condition is met, a control strategy for preventing intermittent vehicle shaking is executed.

[0028] Preferably, the judging whether the modal coupling condition is met according to the engine excitation frequency domain data and the suspension system rigid body modal comprises:

[0029] According to the engine excitation frequency domain data and the suspension system rigid body modal, a modal interval is obtained.

[0030] If the modal interval is less than a preset interval, it is determined that the modal coupling condition is met.

[0031] Preferably, the executing the control strategy for preventing intermittent vehicle shaking comprises:

[0032] Adjusting a working frequency of the carbon can electromagnetic valve and / or adjusting a suspension stiffness of the suspension system.

[0033] A control device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the control method for preventing intermittent vehicle shaking when executing the computer program.

[0034] A computer readable storage medium storing a computer program, wherein the computer program is executable by a processor to implement the control method for preventing intermittent vehicle shaking.

[0035] The control method for preventing intermittent vehicle shaking, the control device, and the storage medium. According to the current working frequency of the carbon can electromagnetic valve, the engine measured data, and the suspension system measured data, the engine excitation frequency domain data and the suspension system rigid body modal are determined, so as to evaluate whether there is a risk of intermittent vehicle shaking by using the engine excitation frequency domain data and the suspension system rigid body modal, to determine whether the control strategy for preventing intermittent vehicle shaking needs to be executed, to avoid the risk of intermittent vehicle shaking, and to ensure the comfort of the vehicle. Understandably, during the development stage of the vehicle, a data model between the engine excitation frequency domain data and the suspension system rigid body modal and the response of intermittent vehicle shaking is established according to the mathematical relationship between the working frequency of the carbon can electromagnetic valve and the engine excitation, the data model is adjusted by reasonable parameter design, the risk of intermittent vehicle shaking is avoided, the later adjustment time is reduced, the adjustment efficiency is improved, and the cost is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0037] Figure 1 is a flow chart of a control method for preventing intermittent shaking of a vehicle in an embodiment of the present application;

[0038] Figure 2 is another flow chart of a control method for preventing intermittent shaking of a vehicle in an embodiment of the present application;

[0039] Figure 3 is another flow chart of a control method for preventing intermittent shaking of a vehicle in an embodiment of the present application;

[0040] Figure 4 is another flow chart of a control method for preventing intermittent shaking of a vehicle in an embodiment of the present application;

[0041] Figure 5 is another flow chart of a control method for preventing intermittent shaking of a vehicle in an embodiment of the present application;

[0042] Figure 6 is another flow chart of a control method for preventing intermittent shaking of a vehicle in an embodiment of the present application. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some 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 work fall within the scope of the present application.

[0044] The control method for preventing intermittent shaking of a vehicle provided by the embodiments of the present application can be applied to a control device. The data model between engine excitation and response of intermittent shaking of a vehicle can be established according to the mathematical relationship between the working frequency of a carbon can electromagnetic valve and the engine excitation, so that whether there is a risk of intermittent shaking of a vehicle can be determined during the development stage of the vehicle, the current real vehicle calibration method can be optimized, the calibration workload can be shortened, the calibration efficiency can be improved, and the cost can be reduced. The control device herein refers to a controller arranged on a vehicle.

[0045] Generally, a carbon can electromagnetic valve is provided between an engine and a carbon can on a vehicle. When the carbon can electromagnetic valve is working, fuel vapor in the carbon can is sucked into an intake manifold of the engine by negative pressure of the intake manifold, mixed with air and combusted. At this time, cylinder pressure of the engine is modulated by working frequency of the carbon can, thereby generating new engine excitation. When the engine excitation is coupled with a mode of a suspension system of a powertrain, vibration of the powertrain is amplified, so that intermittent vehicle shake occurs, affecting vehicle comfort. Therefore, during vehicle development, working frequency of the carbon can electromagnetic valve and the mode of the suspension system can be combined to construct a data model between the intermittent vehicle shake and a response of the intermittent vehicle shake, so that, during vehicle development, the intermittent vehicle shake risk can be avoided by reasonable parameter design, the later tuning time can be reduced, the tuning efficiency can be improved, and the cost can be reduced.

[0046] In an embodiment, as shown in Figure 1 , a control method for preventing intermittent vehicle shake is provided. The method is applied to a control device in Figure 1 , and includes the following steps:

[0047] S101: current working frequency of a carbon can electromagnetic valve, engine measured data and suspension system measured data are acquired;

[0048] S102: engine excitation time domain data are acquired according to the current working frequency of the carbon can electromagnetic valve and the engine measured data;

[0049] S103: engine excitation frequency domain data are acquired by performing time domain to frequency domain processing on the engine excitation time domain data;

[0050] S104: a suspension system rigid mode is acquired by modeling based on the engine excitation time domain data and the suspension system measured data;

[0051] S105: an intermittent vehicle shake prevention control strategy is executed according to the engine excitation frequency domain data and the suspension system rigid mode.

[0052] The current working frequency of the carbon can electromagnetic valve refers to working frequency of the carbon can electromagnetic valve at the current time, which can be understood as an initial working frequency for preventing intermittent vehicle shake, i.e., working frequency before the intermittent vehicle shake prevention control strategy is executed. As an example, the working frequency of the carbon can electromagnetic valve is generally in a range of 5 Hz-25 Hz, which can be adjusted in real time.

[0053] The engine measured data refers to the data related to the engine collected in real time. As an example, the engine measured data includes but is not limited to the engine idle speed, the engine piston area, the connecting rod mass sum, the crank radius and the connecting rod length. The engine idle speed here refers to the engine speed under the idle condition, and specifically refers to the engine idle speed when the water temperature is above 90°. The connecting rod mass sum here includes the sum of the mass of the piston, the piston ring, the piston pin and 1 / 4 to 1 / 3 of the mass of the connecting rod. In this example, the engine idle speed can change with the engine state, while the engine piston area, the connecting rod mass sum, the crank radius and the connecting rod length are fixed values and do not change with the engine state.

[0054] The suspension system measured data refers to the data related to the suspension system collected in real time. As an example, the suspension system measured data includes but is not limited to the powertrain inertia parameter, the current suspension position of the suspension system and the current suspension stiffness of the suspension system. The powertrain inertia parameter can be obtained by test and is a fixed value. The current suspension position of the suspension system refers to the suspension position collected at the current time. The current suspension stiffness of the suspension system refers to the suspension stiffness collected at the current time. The suspension position and the suspension stiffness are adjustable information. Generally, the suspension position is more difficult to adjust, while the suspension stiffness is less difficult to adjust. Therefore, the suspension stiffness can be adjusted by optimization in the subsequent to achieve the purpose of optimizing the suspension system rigid mode and preventing the intermittent shaking of the vehicle.

[0055] As an example, in step S101, the control device can obtain the current working frequency of the carbon can electromagnetic valve, the engine measured data and the suspension system measured data in real time. Specifically, the current working frequency, the engine measured data and the suspension system measured data that change with the engine state are obtained, including but not limited to the current working frequency, the engine idle speed as the engine measured data, the current suspension position of the suspension system and the current suspension stiffness of the suspension system as the suspension system measured data, and other related parameters that do not change with the engine state are pre-stored in the memory. In order to evaluate whether there is a risk of intermittent shaking of the vehicle according to the pre-stored related parameters and the current working frequency of the carbon can electromagnetic valve, the engine idle speed, the current suspension position of the suspension system and the current suspension stiffness.

[0056] The engine excitation time domain data refers to data reflecting changes of an engine excitation signal with time as the independent variable, and is time domain data of engine vibration. As an example, the engine excitation time domain data refers to a time domain distribution of engine excitation. When the forward direction of the automobile is the X-axis direction, the direction perpendicular to the X-axis and in the same plane as the X-axis is the Y-axis direction, and the direction perpendicular to the X-axis and not in the same plane as the X-axis is the Z-axis direction, according to a relevant model of the engine crank connecting rod mechanism, the time domain distribution of engine excitation mainly includes the mass force in the Z direction, the mass torque around the Y direction, and the gas torque around the Y direction. The engine crank connecting rod mechanism is the main motion mechanism of the engine, which converts the reciprocating motion of the piston into the rotary motion of the crankshaft, and converts the force acting on the piston into the torque output by the crankshaft to drive the wheels of the automobile.

[0057] As an example, in step S102, the control device, after obtaining the current working frequency of the carbon can electromagnetic valve and the engine measured data, can calculate the current working frequency of the carbon can electromagnetic valve and the engine measured data by using an engine excitation calculation formula determined based on a kinematic relationship model of the engine crank connecting rod mechanism, to obtain engine excitation time domain data formed based on time domain. The kinematic relationship model is a model reflecting changes of force and torque during the motion of the engine crank connecting rod mechanism, which is set in advance. The engine excitation calculation formula is a formula for calculating engine excitation determined according to the kinematic relationship model of the engine crank connecting rod mechanism, which is pre-stored in the memory, takes the current working frequency of the carbon can electromagnetic valve and the engine measured data as input, and takes engine excitation as output, and specifically takes the mass force in the Z direction, the mass torque around the Y direction, and the gas torque around the Y direction as output.

[0058] The engine excitation frequency domain data is data reflecting amplitude changes of a frequency signal of engine excitation with frequency as the independent variable.

[0059] As an example, in step S103, after obtaining the engine excitation time domain data, the control device can perform time domain to frequency domain processing on the engine excitation time domain data by using a pre-set time domain to frequency domain conversion algorithm, to obtain engine excitation frequency domain data. In this example, the control device can perform FFT (Fast Fourier Transform) conversion processing on the engine excitation time domain data by using a pre-set fast Fourier algorithm, to obtain engine excitation frequency domain data. In this example, the frequency distribution of the engine excitation frequency domain data is within the range of 0-50 Hz, which is easy to cause modal coupling with the rigid body modal of the suspension system, thereby causing intermittent shaking of the automobile, and subsequent coupling judgment and processing operations are required.

[0060] As an example, in step S104, since the suspension system excitation controlling the operation of the suspension system is related to both the engine excitation time-domain data and the actual suspension system data, the control device can construct an excitation kinematic relationship based on the correspondence between the two and the suspension system excitation, formed by the engine excitation time-domain data and the actual suspension system data. Then, based on the excitation kinematic relationship, the eigenvalues ​​in the excitation kinematic relationship can be transformed to form the rigid body mode of the suspension system, so that the rigid body mode of the suspension system is a mathematical model that represents the parameterized design of the vehicle's intermittent vibration, which can quickly determine the risk of the vehicle's intermittent vibration.

[0061] Among them, the anti-intermittent vehicle vibration control strategy is a pre-set control strategy used to prevent intermittent vehicle vibration.

[0062] As an example, in step S105, the control device determines the engine excitation frequency domain data and the rigid body mode of the suspension system, and comprehensively evaluates whether there is a risk of intermittent vehicle vibration based on the engine excitation frequency domain data and the rigid body mode of the suspension system, specifically assessing whether there is modal coupling between the two; if there is a risk of intermittent vehicle vibration, an anti-intermittent vehicle vibration control strategy needs to be implemented to avoid the risk of intermittent vehicle vibration and ensure the comfort of the whole vehicle; if there is no risk of intermittent vehicle vibration, there is no need to implement an anti-intermittent vehicle vibration control strategy, and the control strategy corresponding to the current moment can continue.

[0063] In this embodiment, based on the current operating frequency of the carbon canister solenoid valve, measured engine data, and measured suspension system data, engine excitation frequency domain data and suspension system rigid body modes are determined. This allows for the assessment of the potential risk of intermittent vehicle vibration using these data, thereby determining whether an anti-intermittent vibration control strategy is necessary to mitigate the risk and ensure vehicle comfort. In essence, during vehicle development, a data model is established based on the mathematical relationship between the carbon canister solenoid valve's operating frequency and engine excitation, connecting the engine excitation frequency domain data, suspension system rigid body modes, and the vehicle's intermittent vibration response. Through reasonable parameter design and calibration, the risk of intermittent vehicle vibration can be mitigated, reducing subsequent calibration time, improving calibration efficiency, and lowering costs.

[0064] In one embodiment, such as Figure 2 As shown, step S102, which involves obtaining engine excitation time-domain data based on the current operating frequency of the carbon canister solenoid valve and the engine's measured data, includes:

[0065] S201: Obtain the engine cylinder pressure based on the current operating frequency of the carbon canister solenoid valve and the actual measured data of the engine;

[0066] S202: Obtain engine excitation time domain data according to engine in-cylinder pressure and engine measured data.

[0067] As an example, in step S201, since only when the carbon can electromagnetic valve works, fuel vapor in the carbon can will be sucked into the engine intake manifold by the negative pressure of the engine intake manifold, mixed with air and involved in combustion, thereby causing the risk of intermittent shaking of the vehicle. Therefore, when the carbon can electromagnetic valve works, the control device can obtain the engine in-cylinder pressure according to the current working frequency of the carbon can electromagnetic valve and the engine measured data, so that the engine in-cylinder pressure is related to the current working frequency of the carbon can electromagnetic valve, which is a key parameter affecting the intermittent shaking of the vehicle, to improve the effectiveness of preventing the intermittent shaking of the vehicle.

[0068] As an example, in step S202, when the control device obtains the engine in-cylinder pressure when the carbon can electromagnetic valve works, it needs to calculate the engine in-cylinder pressure and the engine measured data based on the engine excitation calculation formula determined by the kinematic relationship model of the engine crank connecting rod mechanism, to obtain the engine excitation time domain data such as the mass force in the Z direction, the mass torque around the Y direction and the gas torque around the Y direction.

[0069] In this embodiment, first, the engine in-cylinder pressure is obtained according to the current working frequency of the carbon can electromagnetic valve and the engine measured data, to determine the engine in-cylinder pressure, which is a key parameter affecting the intermittent shaking of the vehicle, which helps to improve the effectiveness of preventing the intermittent shaking of the vehicle; then, the engine excitation time domain data based on time domain is determined according to the engine in-cylinder pressure and the engine measured data, so as to subsequently evaluate whether the engine excitation time domain data is coupled with the rigid modal of the suspension system, thereby evaluating whether there is a risk of intermittent shaking of the vehicle.

[0070] In an embodiment, the engine measured data includes an engine idle speed;

[0071] Step S201, i.e., obtaining the engine in-cylinder pressure according to the current working frequency of the carbon can electromagnetic valve and the engine measured data, includes: obtaining the engine in-cylinder pressure according to the current working frequency of the carbon can electromagnetic valve and the engine idle speed.

[0072] The engine idle speed is the engine speed under idle condition, and specifically refers to the engine idle speed when the water temperature is above 90°.

[0073] Generally speaking, only when the carbon canister electromagnetic valve works, the fuel vapor in the carbon canister will be sucked into the intake manifold of the engine by the negative pressure of the engine intake manifold, mixed with air and burned, thereby causing the risk of intermittent shaking of the vehicle; when the carbon canister electromagnetic valve does not work, the fuel vapor will not be sucked into the intake manifold of the engine by the negative pressure of the engine intake manifold, so there is no risk of intermittent shaking of the vehicle.

[0074] As an example, when the carbon canister electromagnetic valve does not work, the engine cylinder pressure mainly depends on the engine idle speed, and a first cylinder pressure formula can be used to calculate the engine idle speed to obtain the engine cylinder pressure when the carbon canister electromagnetic valve does not work, and the first cylinder pressure formula is as follows:

[0075]

[0076] wherein ω1 is the fundamental frequency of the engine idle speed, B0 is the cylinder pressure direct current component amplitude of the engine idle speed, B m is the cylinder pressure amplitude of the m-th harmonic component of the engine idle speed, ψ m is the phase of the m-th harmonic component of the engine idle speed, and M is the harmonic order of the engine idle speed.

[0077] As an example, when the carbon canister electromagnetic valve works, the engine cylinder pressure mainly depends on the current working frequency of the carbon canister electromagnetic valve and the engine idle speed, and a second cylinder pressure formula can be used to calculate the current working frequency of the carbon canister electromagnetic valve and the engine idle speed to obtain the engine cylinder pressure when the carbon canister electromagnetic valve does not work, and the second cylinder pressure formula is as follows:

[0078]

[0079] wherein ω0 is the current working frequency of the carbon canister electromagnetic valve, C0 is the cylinder pressure direct current component amplitude of the current working frequency of the carbon canister electromagnetic valve, which can be a fixed value, C n is the cylinder pressure amplitude of the n-th harmonic component of the current working frequency of the carbon canister electromagnetic valve, ψ n is the phase of the n-th harmonic component of the current working frequency of the carbon canister electromagnetic valve, N is the harmonic order of the current working frequency of the carbon canister electromagnetic valve, ω1 is the fundamental frequency of the engine idle speed, B0 is the cylinder pressure direct current component amplitude of the engine idle speed, B m is the cylinder pressure amplitude of the m-th harmonic component of the engine idle speed, ψ m is the phase of the m-th harmonic component of the engine idle speed, and M is the harmonic order of the engine idle speed.

[0080] In the embodiment, when the carbon can electromagnetic valve is working, the engine in-cylinder pressure is determined based on the current working frequency of the carbon can electromagnetic valve and the engine idle speed, so that the engine in-cylinder pressure is related to the current working frequency of the carbon can electromagnetic valve, which is a key parameter affecting the intermittent shaking of the automobile, and the accuracy of obtaining the engine in-cylinder pressure is ensured, so as to improve the effectiveness of preventing the intermittent shaking of the automobile.

[0081] In an embodiment, as shown in FIG. 2, the step S202 of obtaining the engine excitation time domain data according to the engine in-cylinder pressure and the engine measured data comprises: Figure 3

[0082] S301: calculating the engine measured data by using the mass force formula to obtain the mass force;

[0083] S302: calculating the engine measured data by using the mass torque formula to obtain the mass torque;

[0084] S303: calculating the engine in-cylinder pressure and the engine measured data by using the gas torque formula to obtain the gas torque;

[0085] The engine excitation time domain data comprises the mass force, the mass torque and the gas torque.

[0086] The mass force formula is a formula for calculating the mass force, the mass torque formula is a formula for calculating the mass torque, and the gas torque formula is a formula for calculating the gas torque.

[0087] As an example, in the step S301, the control device can calculate the engine measured data by using the pre-set mass force formula, specifically, the engine idle speed, the total mass of the connecting rod, the curved side radius and the connecting rod length, to obtain the mass force. In this example, the mass force formula is a formula taking the engine idle speed, the total mass of the connecting rod, the curved side radius and the connecting rod length as input and taking the mass force as output.

[0088] For example, when the automobile engine is a four-cylinder engine, the mass force in the Z-axis direction is the sum of the mass forces in the Z-axis direction of the four engines, and the mass force formula can be F z4 =-4m s rω 2 λ p cos2ωt, the engine idle speed, the total mass of the connecting rod, the curved side radius and the connecting rod length are calculated to obtain the mass force, wherein F z4 is the sum of the mass forces in the Z-axis direction of the four engines, m s is the total mass of the connecting rod, r is the curved side radius, ω is the engine idle speed, and λ p ​= r / l, l is the length of the connecting rod.

[0089] As an example, in step S302, the control device can use a pre-set mass torque formula to calculate the engine measured data, specifically, the engine idle speed, the total mass of the connecting rod, the curved radius, and the length of the connecting rod, to obtain the mass torque. In this example, the mass torque formula is a formula that takes the engine idle speed, the total mass of the connecting rod, the curved radius, and the length of the connecting rod as input, and outputs the mass torque.

[0090] For example, when the automobile engine is a four-cylinder engine, the mass torque of the automobile engine around the Y-axis direction is the sum of the mass torques of the four engines around the Y-axis direction, and the mass torque formula The engine idle speed, the total mass of the connecting rod, the curved radius, and the length of the connecting rod are calculated to obtain the mass torque, where M ym4 is the sum of the mass torques of the four engines around the Y-axis direction, m s is the total mass of the connecting rod, r is the curved radius, ω is the engine idle speed, and λ p = r / l, l is the length of the connecting rod.

[0091] As an example, in step S303, the control device can use a pre-set gas torque formula to calculate the engine measured data, specifically, the engine in-cylinder pressure, the engine piston area, the engine idle speed, the curved radius, and the length of the connecting rod, to obtain the gas torque. In this example, the gas torque formula is a formula that takes the engine in-cylinder pressure, the engine piston area, the engine idle speed, the curved radius, and the length of the connecting rod as input, and outputs the gas torque.

[0092] For example, when the automobile engine is a four-cylinder engine, the gas torque of the automobile engine around the Y-axis direction is the sum of the gas torques of the four engines around the Y-axis direction, and the gas torque formula The engine in-cylinder pressure, the engine piston area, the engine idle speed, the curved radius, and the length of the connecting rod are calculated to obtain the gas torque, where M yg4 is the sum of the gas torques of the four engines around the Y-axis direction, P(t) is the engine in-cylinder pressure, A is the engine piston area, r is the curved radius, ω is the engine idle speed, and λ p = r / l, l is the length of the connecting rod.

[0093] In this embodiment, the engine in-cylinder pressure and different engine measured data are used as inputs to calculate the mass force, mass torque and gas torque, etc. engine excitation time domain data, so that the engine excitation time domain data is related to the key parameter of the engine in-cylinder pressure affecting the intermittent shaking of the automobile, which helps to improve the effectiveness of preventing the intermittent shaking of the automobile.

[0094] In an embodiment, as shown in Figure 4 Step S104, i.e. modeling based on engine excitation time domain data and measured data of the suspension system, obtaining the rigid body modal of the suspension system, includes:

[0095] S401: modeling based on engine excitation time domain data and measured data of the suspension system, obtaining the excitation kinematics relationship;

[0096] S402: performing fast Fourier transform on the excitation kinematics relationship to obtain the frequency domain characteristic value corresponding to the excitation kinematics relationship, and determining the rigid body modal of the suspension system based on the frequency domain characteristic value.

[0097] As an example, in step S401, since the engine excitation time domain data includes the mass force F z4 , the mass torque M ym4 and the gas torque M yg4 of the powertrain excitation, according to the pre-set six-degree-of-freedom model of the suspension system, the suspension system excitation formula can be determined as follows:

[0098]

[0099] Since the measured data of the suspension system includes but is not limited to the inertia parameters of the powertrain, the current suspension position of the suspension system and the current suspension stiffness of the suspension system, the displacement matrix x(t) of the suspension system can be constructed based on the current suspension position of the suspension system; the mass matrix m of the suspension system can be determined based on the inertia parameters of the powertrain, which can be obtained by test; the stiffness matrix k of the suspension system can be constructed based on the current suspension stiffness of the suspension system, which can be obtained by test; then, according to the displacement matrix x(t), the mass matrix m and the stiffness matrix k of the suspension system, the suspension system excitation formula can be determined as follows:

[0100]

[0101] wherein, is the acceleration matrix formed by twice derivation of the displacement matrix x(t). As can be seen from the above formula (1) and formula (2), the excitation kinematics relationship of the undamped system can be established:

[0102]

[0103] In the case where there is a risk of intermittent shaking of the automobile when the carbon can solenoid is operating, the formula (3) is, and the engine in-cylinder pressure P(t) is: These parameters can be input into the above formula (3) to complete the construction of the excitation kinematics relationship.

[0104] As an example, in step S402, after the excitation kinematics relationship is constructed based on the above formula (3), a Fast Fourier Transform (FFT) can be performed on the constructed excitation kinematics relationship to convert the original time-domain eigenvalues in the excitation kinematics relationship into frequency-domain eigenvalues, and then based on all the frequency-domain eigenvalues, the rigid body modal of the suspension system is determined. That is, the rigid body modal of the suspension system is characterized as a modal formed by multiple frequency-domain eigenvalues, so that subsequent comprehensive judgment of the risk of intermittent shaking of the automobile can be based on the rigid body modal of the suspension system, and the mathematical model is established for parameterized design of the intermittent shaking of the automobile in the vehicle development stage.

[0105] In this embodiment, first, the excitation kinematics relationship formed by the engine excitation time-domain data and the suspension system measured data is constructed according to the relationship between the suspension system excitation and the engine excitation time-domain data and the suspension system measured data; and then a Fast Fourier Transform is performed on the excitation kinematics relationship to determine the rigid body modal of the suspension system, so that the rigid body modal of the suspension system is characterized as a mathematical model established for parameterized design of the intermittent shaking of the automobile, and the risk of intermittent shaking of the automobile can be quickly judged.

[0106] In an embodiment, as shown in Figure 5 Step S105, that is, according to the engine excitation frequency-domain data and the rigid body modal of the suspension system, a control strategy for preventing intermittent shaking of the automobile is executed, which includes:

[0107] S501: According to the engine excitation frequency-domain data and the rigid body modal of the suspension system, it is judged whether the modal coupling condition is met;

[0108] S502: If the modal coupling condition is met, a control strategy for preventing intermittent shaking of the automobile is executed.

[0109] The modal coupling condition is a condition that is set in advance to evaluate whether the modal coupling standard is met.

[0110] As an example, in step S501, the control device can determine whether the engine excitation frequency-domain data and the rigid body modal of the suspension system exist modal coupling according to the engine excitation frequency-domain data and the rigid body modal of the suspension system, and judge whether the modal coupling condition set in advance is met.

[0111] As an example, in step S502, the control device can determine that the engine excitation frequency domain data and the suspension system rigid body mode are coupled in a specific frequency band when the engine excitation frequency domain data and the suspension system rigid body mode satisfy the modal coupling condition, the vibration of the powertrain will be amplified, and the intermittent shaking of the automobile is prone to occur. Therefore, the anti-intermittent shaking control strategy needs to be executed to avoid the risk of intermittent shaking of the automobile and ensure the comfort of the vehicle. If there is no risk of intermittent shaking of the automobile, the anti-intermittent shaking control strategy does not need to be executed, and the control strategy corresponding to the current time can be continued.

[0112] In an embodiment, as shown in step S501, the determination of whether the modal coupling condition is satisfied according to the engine excitation frequency domain data and the suspension system rigid body mode includes: Figure 6

[0113] S601: According to the engine excitation frequency domain data and the suspension system rigid body mode, the modal interval is obtained.

[0114] S602: If the modal interval is less than the preset interval, it is determined that the modal coupling condition is satisfied.

[0115] The modal interval refers to the frequency interval calculated according to the engine excitation frequency domain data and the suspension system rigid body mode. The preset interval is a frequency interval preset for evaluating whether the modal coupling standard is reached, which can be set to 1 Hz.

[0116] As an example, in step S601, the control device can calculate the absolute value of the frequency difference between the engine excitation frequency domain data and the suspension system rigid body mode, and determine the absolute value of the frequency difference as the modal interval.

[0117] As an example, in step S602, after the modal interval is calculated and determined, the control device can compare the modal interval with the preset interval. If the modal interval is less than the preset interval, it means that the frequency interval between the frequency of the engine excitation frequency domain data and the frequency of the suspension system rigid body mode is small, and the probability of modal coupling is large. Therefore, it can be determined that the modal coupling condition is satisfied. Correspondingly, if the modal interval is not less than the preset interval, it means that the frequency interval between the frequency of the engine excitation frequency domain data and the frequency of the suspension system rigid body mode is large, and the probability of modal coupling is small. Therefore, it can be determined that the modal coupling condition is not satisfied.

[0118] In an embodiment, in step S105 or step S502, executing the anti-intermittent shaking control strategy includes adjusting the working frequency of the carbon can electromagnetic valve and / or adjusting the suspension stiffness of the suspension system.

[0119] ​As an example, since the engine excitation frequency domain data is related to the working frequency of the carbon can electromagnetic valve, the working frequency of the carbon can electromagnetic valve is adjustable in the range of 5-25 Hz, the suspension system rigid mode is in the range of 5-20 Hz, and the change of the suspension system rigid mode mainly depends on the suspension stiffness of the measured data of the suspension system, therefore, when it is determined that the engine excitation frequency domain data and the suspension system rigid mode exist mode coupling, specifically, when the mode interval of the engine excitation frequency domain data and the suspension system rigid mode is less than the preset interval, the anti-car intermittent jitter control strategy needs to be executed, including:

[0120] The first control strategy is to only adjust the working frequency of the carbon can electromagnetic valve, and then adjust the engine excitation frequency domain data, so that the mode interval of the adjusted engine excitation frequency domain data and the suspension system rigid mode is not less than the preset interval, and there is no mode coupling, so as to achieve the decoupling purpose.

[0121] The second control strategy is to only adjust the suspension stiffness of the suspension system, and then adjust the suspension system rigid mode, so that the mode interval of the engine excitation data and the adjusted suspension system rigid mode is not less than the preset interval, and there is no mode coupling, so as to achieve the decoupling purpose.

[0122] The third control strategy is to simultaneously adjust the working frequency of the carbon can electromagnetic valve and the suspension stiffness of the suspension system, and then adjust the engine excitation frequency domain data and the suspension system rigid mode, so that the mode interval of the adjusted engine excitation data and the adjusted suspension system rigid mode is not less than the preset interval, and there is no mode coupling, so as to achieve the decoupling purpose.

[0123] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation on the execution process of the embodiment of the present application.

[0124] In an embodiment, a control device is provided, including a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the computer program to implement the anti-car intermittent jitter control method in the above embodiment, for example Figure 1 S101-S105 shown in the figure, or Figure 2 to Figure 6 In order to avoid repetition, it will not be repeated here.

[0125] In an embodiment, a computer readable storage medium is provided, and the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the anti-car intermittent jitter control method in the above embodiment, for example Figure 1 S101-S105 shown in the figure, or Figures 2 to 6As shown in the middle, to avoid repetition, it will not be described here.

[0126] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by a computer program instructing the relevant hardware, and the computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments of the method. Any reference to a storage, memory, database or other medium used in the embodiments provided by the present application can include a non-volatile and / or volatile storage. The non-volatile storage can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. The volatile storage can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0127] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above-mentioned functional units and modules is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above.

[0128] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalent ones. Such modifications or replacements do not change the essence of the corresponding technical solutions, and should be included in the protection scope of the present application.

Claims

1. A method for controlling intermittent vehicle vibration, characterized in that, The method comprises the following steps: acquiring a current working frequency of a carbon canister electromagnetic valve, engine measured data, and suspension system measured data; the engine measured data comprises an engine idle speed; acquiring engine in-cylinder pressure according to the current working frequency of the carbon canister electromagnetic valve and the engine idle speed; acquiring engine excitation time domain data according to the engine in-cylinder pressure and the engine measured data; performing time domain to frequency domain processing on the engine excitation time domain data to acquire engine excitation frequency domain data; modeling based on the engine excitation time domain data and the suspension system measured data to acquire suspension system rigid body modal; executing an automobile intermittent judder control strategy according to the engine excitation frequency domain data and the suspension system rigid body modal.

2. The method of claim 1, wherein the control method is for preventing the intermittent jolt of the vehicle. The step of acquiring engine excitation time domain data according to the engine in-cylinder pressure and the engine measured data comprises the following steps: calculating the engine measured data by using a mass force formula to acquire a mass force; calculating the engine measured data by using a mass torque formula to acquire a mass torque; calculating the engine in-cylinder pressure and the engine measured data by using a gas torque formula to acquire a gas torque; wherein the engine excitation time domain data comprises the mass force, the mass torque, and the gas torque.

3. The method of claim 1, wherein the control method is for preventing the intermittent jolt of the vehicle. The step of modeling based on the engine excitation time domain data and the suspension system measured data to acquire suspension system rigid body modal comprises the following steps: modeling based on the engine excitation time domain data and the suspension system measured data to acquire excitation kinematics; performing fast Fourier transform on the excitation kinematics to acquire frequency domain eigenvalues corresponding to the excitation kinematics, and determining the suspension system rigid body modal based on the frequency domain eigenvalues.

4. The method of claim 1, wherein the control method is for preventing the intermittent jolt of the vehicle. The step of executing an automobile intermittent judder control strategy according to the engine excitation frequency domain data and the suspension system rigid body modal comprises the following steps: determining whether a modal coupling condition is met according to the engine excitation frequency domain data and the suspension system rigid body modal; if the modal coupling condition is met, executing the automobile intermittent judder control strategy.

5. The method of claim 4, wherein the control method is a control method for preventing the intermittent jolt of the vehicle, characterized by The step of determining whether a modal coupling condition is met according to the engine excitation frequency domain data and the suspension system rigid body modal comprises the following steps: acquiring a modal interval according to the engine excitation frequency domain data and the suspension system rigid body modal; if the modal interval is less than a preset interval, it is determined that the modal coupling condition is met.

6. The method of claim 1 or 4, wherein the control method is a method of preventing intermittent juddering of an automobile. The step of executing the automobile intermittent judder control strategy comprises the following steps: adjusting a working frequency of the carbon canister electromagnetic valve and / or adjusting a suspension stiffness of the suspension system.

7. A control device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, The processor executes the computer program to implement the automobile intermittent judder control method according to any one of claims 1 to 6.

8. A computer-readable storage medium storing a computer program, the computer-readable storage medium comprising: The computer program is executed by the processor to implement the automobile intermittent judder control method according to any one of claims 1 to 6.

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