A hydraulic pressure prediction control method and system for an automotive brake wheel cylinder

Abstract

The present invention discloses a hydraulic pressure prediction control method and system for an automotive brake wheel cylinder. The method is applied to an automotive hydraulic braking system and includes, after initializing in response to the power-on of the hydraulic braking system, acquiring the operation data of the hydraulic braking system; based on the operation data, obtaining a hydraulic pressure vector control set of the brake wheel cylinder; based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establishing a prediction equation for the hydraulic pressure of the brake wheel cylinder; based on the prediction equation for the hydraulic pressure of the brake wheel cylinder, constructing a cost function for the control of the hydraulic pressure of the brake wheel cylinder; based on the cost function, obtaining the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve, and realizing the adjustment of the hydraulic pressure of the brake wheel cylinder through the cooperation of the inlet valve and the outlet valve according to the optimal state vectors. The present invention reduces the complexity of the control structure and the cost of the hydraulic pressure control of the brake wheel cylinder, and through model prediction and cost function optimization, obtains the optimal on-off control of the inlet valve and the outlet valve.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive braking, and particularly to a hydraulic pressure prediction control method and system for an automotive brake wheel cylinder. Background Art

[0002] The automotive braking system is a core component of the vehicle chassis, the basis for the safe and reliable driving of the vehicle, and the key to supporting the development of important functions such as automotive braking energy recovery, anti-lock braking, drive slip control, electronic stability control, automatic emergency braking, and adaptive cruise control. Among them, in the above braking system, the wheel cylinder hydraulic pressure control is the key to determining the performance of the braking system, which will directly affect the safety, comfort, and economy of the vehicle.

[0003] Currently, in the prior art, the wheel cylinder hydraulic pressure control is mainly achieved by using proportional solenoid valves and on-off solenoid valves. Among them, the proportional solenoid valve can linearly adjust the valve port opening and the hydraulic pressure, with high pressure control accuracy, but its processing and manufacturing process is complex and the cost is high, and it does not yet have the conditions for vehicle application; the on-off solenoid valve usually uses the PWM control method to achieve the wheel cylinder hydraulic pressure regulation, but the PWM control method of the on-off solenoid valve requires an additional PWM generator, which increases the structural complexity and cost of the control system; and the existing on-off solenoid valve control method cannot explicitly handle the switching non-linearity of the on-off solenoid valve, so it cannot represent the direct quantitative relationship between the brake wheel cylinder hydraulic pressure and the switching state of the on-off solenoid valve, and thus cannot directly obtain the optimal switching state of the on-off solenoid valve by solving the optimization problem. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the related art to some extent.

[0005] To this end, the present invention proposes a hydraulic pressure prediction control method for an automotive brake wheel cylinder, which uses predictive control to obtain the switching state vector of the inlet valve and the outlet valve at the current moment, cancels the PWM generator module in the classical PWM control method, and reduces the control structure complexity and cost of the brake wheel cylinder hydraulic pressure control; at the same time, a direct quantitative relationship between the brake wheel cylinder hydraulic pressure and the switching state vector of the inlet valve and the outlet valve is established, and through model prediction and cost function optimization, the optimal switching control of the inlet valve and the outlet valve can be obtained.

[0006] Another object of the present invention is to propose a hydraulic pressure prediction control system for an automotive brake wheel cylinder.

[0007] To achieve the above object, on the one hand, the present invention proposes a hydraulic pressure prediction control method for an automotive brake wheel cylinder, and the method is applied to an automotive hydraulic braking system, including:

[0008] After initializing in response to the power-on of the hydraulic braking system, obtain the operating data of the hydraulic braking system, where the operating data includes the hydraulic pressure of the brake wheel cylinder;

[0009] Based on the operating data, obtain the hydraulic pressure vector control set of the brake wheel cylinder;

[0010] Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establish a prediction equation for the hydraulic pressure of the brake wheel cylinder;

[0011] Based on the prediction equation of the hydraulic pressure of the brake wheel cylinder, construct a cost function for the control of the hydraulic pressure of the brake wheel cylinder;

[0012] Based on the cost function, obtain the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vector of the corresponding inlet valve and outlet valve, and through the cooperation of the inlet valve and the outlet valve according to the optimal state vector, realize the adjustment of the hydraulic pressure of the brake wheel cylinder.

[0013] The hydraulic pressure prediction control method of the vehicle brake wheel cylinder according to the embodiment of the present invention may further have the following additional technical features:

[0014] In an embodiment of the present invention, the operating data includes the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, the hydraulic pressure of the brake wheel cylinder, and the combined switch states of the inlet valve and the outlet valve. The obtaining of the hydraulic pressure vector control set of the brake wheel cylinder based on the operating data includes: constructing a state vector set of the inlet valve and the outlet valve and the hydraulic pressure vector control set of the brake wheel cylinder according to the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, and the combined switch states of the inlet valve and the outlet valve.

[0015] In an embodiment of the present invention, the establishing of the prediction equation for the hydraulic pressure of the brake wheel cylinder based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder includes:

[0016] Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, obtain the discrete state space equation of the hydraulic pressure;

[0017] Estimate the lumped disturbance term of the brake wheel cylinder in real time to obtain an estimated value of the lumped disturbance term;

[0018] Based on the estimated value of the lumped disturbance term and the discrete state space equation, establish a prediction equation for the hydraulic pressure of the brake wheel cylinder.

[0019] In an embodiment of the present invention, the obtaining of the discrete state space equation of the hydraulic pressure based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder includes:

[0020] Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establish the dynamic hydraulic pressure equation of the brake wheel cylinder;

[0021] Convert the dynamic hydraulic pressure equation of the brake wheel cylinder into a state space equation;

[0022] Discretize the state space equation to obtain the discrete state space equation of the hydraulic pressure.

[0023] To achieve the above object, on the other hand, the present invention proposes a hydraulic pressure prediction control system for an automotive brake wheel cylinder. The system is applied to an automotive hydraulic braking system. The system includes a data processing module, a building module, a hydraulic pressure cost function module, and an optimal hydraulic pressure vector calculation module. Among them,

[0024] The data processing module is configured to, after initializing in response to the power-on of the hydraulic braking system, obtain the operation data of the hydraulic braking system. Among them, the operation data includes the hydraulic pressure of the brake wheel cylinder;

[0025] The data processing module is further configured to obtain the hydraulic pressure vector control set of the brake wheel cylinder based on the operation data;

[0026] The building module is configured to establish a prediction equation of the hydraulic pressure of the brake wheel cylinder based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder;

[0027] The hydraulic pressure cost function module is configured to construct a cost function for controlling the hydraulic pressure of the brake wheel cylinder based on the prediction equation of the hydraulic pressure of the brake wheel cylinder;

[0028] The optimal hydraulic pressure vector calculation module is configured to obtain the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve based on the cost function, and cooperate through the inlet valve and the outlet valve according to the optimal state vectors to realize the hydraulic pressure regulation of the brake wheel cylinder.

[0029] In an embodiment of the present invention, the data processing module is specifically configured to:

[0030] Construct a state vector set of the inlet valve and the outlet valve and the hydraulic pressure vector control set of the brake wheel cylinder according to the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, and the combined switch states of the inlet valve and the outlet valve.

[0031] In an embodiment of the present invention, the building module further includes a wheel cylinder hydraulic pressure model module, a disturbance observation module, and a hydraulic pressure prediction model module. Among them,

[0032] The wheel cylinder hydraulic pressure model module is used to obtain the discrete state - space equation of the hydraulic pressure based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder;

[0033] The disturbance observation module is used to estimate the lumped disturbance term of the brake wheel cylinder in real - time to obtain an estimated value of the lumped disturbance term;

[0034] The hydraulic pressure prediction model module is used to establish a prediction equation for the hydraulic pressure of the brake wheel cylinder based on the estimated value of the lumped disturbance term and the discrete state - space equation.

[0035] In an embodiment of the present invention, the wheel cylinder hydraulic pressure model module is specifically used for:

[0036] Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establish the dynamic hydraulic pressure equation of the brake wheel cylinder;

[0037] Convert the dynamic hydraulic pressure equation of the brake wheel cylinder into a state - space equation;

[0038] Perform discretization processing on the state - space equation to obtain the discrete state - space equation of the hydraulic pressure.

[0039] To achieve the above object, on the one hand, the present invention proposes a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it can implement any of the above - mentioned methods.

[0040] To achieve the above object, on the one hand, the present invention proposes a computer storage medium, wherein the computer storage medium stores computer - executable instructions; after the computer - executable instructions are executed by a processor, they can implement any of the above - mentioned methods.

[0041] The hydraulic pressure prediction control method and system for an automotive brake wheel cylinder according to the embodiments of the present invention use predictive control to obtain the switch - state vector of the inlet valve and the outlet valve at the current moment, cancel the PWM generator module in the classical PWM control mode, reduce the complexity of the control structure and the cost of the hydraulic pressure control of the brake wheel cylinder; at the same time, a direct quantitative relationship between the hydraulic pressure of the brake wheel cylinder and the switch - state vector of the inlet valve and the outlet valve is established. Through model prediction and cost - function optimization, the optimal switch control of the inlet valve and the outlet valve can be obtained.

[0042] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present invention. Description of the Drawings

[0043] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of embodiments in conjunction with the accompanying drawings, where:

[0044] Figure 1 is a schematic diagram of an automotive hydraulic braking system according to an embodiment of the present invention;

[0045] Figure 2 is a flowchart of a method for predicting the hydraulic pressure of an automotive brake wheel cylinder according to an embodiment of the present invention;

[0046] Figure 3 is a structural diagram of a system for predicting the hydraulic pressure of an automotive brake wheel cylinder according to an embodiment of the present invention;

[0047] wherein, 1, high-pressure supply unit; 2, first pressure sensor; 3, inlet valve; 4, brake wheel cylinder; 5, second pressure sensor; 6, outlet valve; 7, low-pressure oil return unit; 8, hydraulic pressure prediction control system; 81, data processing module; 82, wheel cylinder hydraulic pressure model module; 83, disturbance observation module; 84, hydraulic pressure prediction model module; 85, hydraulic pressure cost function module; 86, optimal hydraulic pressure vector calculation module; 87, establishment module. Detailed Embodiments

[0048] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0049] To enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0050] In an embodiment of the present invention, Figure 1 is a schematic diagram of an automotive hydraulic braking system according to an embodiment of the present invention. As Figure 1As shown in the figure, the automotive hydraulic braking system specifically includes a high-pressure supply unit 1, a first pressure sensor 2, an inlet valve 3, a brake wheel cylinder 4, a second pressure sensor 5, an outlet valve 6, a low-pressure oil return unit 7, and a hydraulic pressure prediction control system 8. The high-pressure supply unit 1 is used to provide a stable and reliable high-pressure hydraulic source; the first pressure sensor 2 is used to measure the hydraulic pressure of the high-pressure supply unit 1; the inlet valve 3 is a switching solenoid valve, and by adjusting its open and closed states, it controls the volume flow rate flowing from the high-pressure supply unit 1 into the brake wheel cylinder 4, thereby realizing the pressurization of the brake wheel cylinder 4; the brake wheel cylinder 4 realizes pressure increase and decrease under the actions of the inlet valve 3 and the outlet valve 6 to brake the vehicle; the second pressure sensor 5 is used to measure the hydraulic pressure of the brake wheel cylinder 4; the outlet valve 6 is a switching solenoid valve, and by adjusting its open and closed states, it controls the volume flow rate flowing from the brake wheel cylinder 4 into the low-pressure oil return unit 7, thereby realizing the decompression of the brake wheel cylinder 4; the low-pressure oil return unit 7 is used to recover the brake fluid discharged from the brake wheel cylinder 4; the hydraulic pressure prediction control system 8 is used to control the open and closed states of the inlet valve 3 and the outlet valve 6.

[0051] The following describes a hydraulic pressure prediction control method and system for an automotive brake wheel cylinder according to an embodiment of the present invention with reference to the accompanying drawings.

[0052] Figure 1 It is a flowchart of the hydraulic pressure prediction control method for an automotive brake wheel cylinder according to an embodiment of the present invention.

[0053] As Figure 1 shown, this method is applied to an automotive hydraulic braking system and includes:

[0054] S1. After initializing in response to the power-on of the hydraulic braking system, obtain the operation data of the hydraulic braking system;

[0055] In an embodiment of the present invention, the above operation data may include the hydraulic pressure of the brake wheel cylinder, the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, the hydraulic pressure of the brake wheel cylinder, and the combined switch states of the inlet valve and the outlet valve.

[0056] S2. Based on the operation data, obtain a hydraulic pressure vector control set for the brake wheel cylinder;

[0057] In an embodiment of the present invention, after obtaining the operation data through the above steps, a hydraulic pressure vector control set for the brake wheel cylinder can be obtained based on the operation data. Among them, in an embodiment of the present invention, the method for obtaining the hydraulic pressure vector control set for the brake wheel cylinder based on the operation data may include constructing a state vector set of the inlet valve and the outlet valve and a hydraulic pressure vector control set for the brake wheel cylinder according to the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, and the combined switch states of the inlet valve and the outlet valve.

[0058] Specifically, in an embodiment of the present invention, the state vectors of the inlet valve and the outlet valve and the hydraulic pressure vector of the brake wheel cylinder can be defined according to the combined switch states of the inlet valve and the outlet valve, and a finite set of state vectors can be constructed and the hydraulic pressure vector control set Among them, the set of state vectors and the hydraulic pressure vector control set are represented as follows:

[0059]

[0060] Among them, is the set of state vectors of the inlet valve and the outlet valve, and S0, S1, and S2 represent the effective state vectors of the inlet valve and the outlet valve. S I and S O are the switch state quantities of the inlet valve and the outlet valve respectively, and S I , S O ∈{0, 1} can take the values 0 and 1, where 0 represents the off state and 1 represents the on state. S0 = (0, 0) is the state where both the inlet valve and the outlet valve are off, S1 = (0, 1) is the state where the inlet valve 3 is off and the outlet valve 6 is on, and S2 = (1, 0) is the state where the inlet valve is on and the outlet valve is off.

[0061] And, is the set of hydraulic pressure vectors of the brake wheel cylinder. Q0 is the volume flow rate of the brake fluid flowing into the brake wheel cylinder when both the inlet valve and the outlet valve are off, Q `1 is the volume flow rate of the brake fluid flowing into the brake wheel cylinder when the inlet valve is off and the outlet valve is on, and Q2 is the volume flow rate of the brake fluid flowing into the brake wheel cylinder when the inlet valve is on and the outlet valve is off. The specific definitions are as follows:

[0062]

[0063] Among them, S is the state vector of the inlet valve and the outlet valve at the current moment, Q w is the volume flow rate of the brake fluid flowing into the brake wheel cylinder at the current moment, P h and P r are the hydraulic pressures of the high-pressure supply unit and the low-pressure oil return unit respectively, c d is the flow coefficient, A s is the flow-through area, and ρ is the density of the brake fluid.

[0064] S3, based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establish a prediction equation for the hydraulic pressure of the brake wheel cylinder;

[0065] In one embodiment of the present invention, after obtaining the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder through the above steps, a prediction equation for the hydraulic pressure of the brake wheel cylinder can be established based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder.

[0066] Specifically, in one embodiment of the present invention, the method for establishing a prediction equation for the hydraulic pressure of the brake wheel cylinder based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder may include the following steps:

[0067] Step 1: Obtain the discrete state - space equation of the hydraulic pressure based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder;

[0068] Step 2: Estimate the lumped disturbance term of the brake wheel cylinder in real - time to obtain an estimated value of the lumped disturbance term;

[0069] Step 3: Establish a prediction equation for the hydraulic pressure of the brake wheel cylinder based on the estimated value of the lumped disturbance term and the discrete state - space equation.

[0070] Among them, in one embodiment of the present invention, the method for obtaining the discrete state - space equation of the hydraulic pressure based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder may include the following steps:

[0071] Step a: Establish the dynamic hydraulic pressure equation of the brake wheel cylinder based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder;

[0072] Among them, in one embodiment of the present invention, the dynamic hydraulic pressure equation of the brake wheel cylinder established based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder is as follows:

[0073]

[0074] Among them, P w and V w are respectively the hydraulic pressure and volume of the brake wheel cylinder, x w and A w are respectively the piston displacement and cross - sectional area of the brake wheel cylinder, d w is the unmodeled dynamics of the hydraulic system of the brake wheel cylinder, and κ w is the bulk modulus of the brake fluid.

[0075] Step b: Convert the dynamic hydraulic pressure equation of the brake wheel cylinder into a state - space equation;

[0076] In one embodiment of the present invention, converting the dynamic hydraulic pressure equation of the brake wheel cylinder into a state - space equation is as follows:

[0077]

[0078] where x1 = P w is the hydraulic pressure of the brake wheel cylinder, x2 = -A w x w +d w is the lumped disturbance term of the brake wheel cylinder hydraulic system, h(t) is the first-order time derivative of x2, and u = Q w is the volume flow rate of the brake fluid flowing into the brake wheel cylinder, and b = κ w / V w is the control coefficient.

[0079] Step c: Discretize the state space equation to obtain the discrete state space equation of the hydraulic pressure.

[0080] In an embodiment of the present invention, after discretizing the state space equation, the discrete state space equation of the hydraulic pressure of the brake wheel cylinder is as follows:

[0081]

[0082] where x1(k) and x1(k + 1) are the hydraulic pressures of the brake wheel cylinder at time k and k + 1 respectively, x2(k) and x2(k + 1) are the lumped disturbance terms of the brake wheel cylinder hydraulic system at time k and k + 1 respectively, u(k) is the volume flow rate of the brake fluid flowing into the brake wheel cylinder at time k, h(k) is the first-order time derivative of the lumped disturbance term of the brake wheel cylinder hydraulic system at time k, B k = bT s and A k = T s are the control matrix and system matrix of the discrete state space equation of the hydraulic pressure of the brake wheel cylinder respectively, and T s is the sampling time.

[0083] Moreover, in an embodiment of the present invention, the lumped disturbance term of the brake wheel cylinder can be estimated in real time through the first formula to obtain the estimated value of the lumped disturbance term, where the first formula is:

[0084]

[0085] where z1(k) and z1(k + 1) are the estimated values of the hydraulic pressure of the brake wheel cylinder at time k and k + 1 respectively, z2(k) and z2(k + 1) are the estimated values of the lumped disturbance term of the brake wheel cylinder hydraulic system at time k and k + 1 respectively, and L1>0 and L2>0 are the observer gains.

[0086] Moreover, in an embodiment of the present invention, the lumped disturbance term of the brake wheel cylinder is estimated in real time through the above-mentioned extended state observation method, so that the subsequent prediction equation is corrected and compensated based on the estimated value of the lumped disturbance term, enhancing the robustness of the brake wheel cylinder hydraulic pressure control and reducing the calibration workload of the algorithm.

[0087] Furthermore, in an embodiment of the present invention, based on the estimated value of the lumped disturbance term and the discrete state - space equation, a prediction equation for the hydraulic pressure of the brake wheel cylinder is established as follows:

[0088]

[0089] Wherein, is the one - step predicted value of the hydraulic pressure of the brake wheel cylinder at time k + 1. And, based on the one - step predicted value of the hydraulic pressure of the brake wheel cylinder, the two - step predicted value of the hydraulic pressure of the brake wheel cylinder can be obtained through the above prediction equation as follows:

[0090]

[0091] Wherein, is the two - step predicted value of the hydraulic pressure of the brake wheel cylinder at time k + 2.

[0092] S4. Based on the prediction equation of the hydraulic pressure of the brake wheel cylinder, construct a cost function for controlling the hydraulic pressure of the brake wheel cylinder;

[0093] Wherein, in an embodiment of the present invention, after obtaining the two - step predicted value of the hydraulic pressure of the brake wheel cylinder through the above steps, based on the two - step predicted value of the hydraulic pressure of the brake wheel cylinder, a cost function for controlling the hydraulic pressure of the brake wheel cylinder is constructed as follows:

[0094]

[0095] Wherein, J is the cost function of the hydraulic pressure of the brake wheel cylinder 4, x 1d (k + 2) is the reference value of the hydraulic pressure of the brake wheel cylinder 4 at time k + 2, and λ>0 is the proportionality coefficient.

[0096] S5. Based on the cost function, obtain the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve, and through the cooperation of the inlet valve and outlet valve according to the optimal state vectors, realize the hydraulic pressure regulation of the brake wheel cylinder.

[0097] In an embodiment of the present invention, based on the cost function, the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve can be obtained through the second formula, wherein, the second formula is:

[0098]

[0099] And, in an embodiment of the present invention, by solving the above - mentioned second formula, the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve can be obtained. Wherein, the solving methods include but are not limited to the enumeration method and mixed - integer programming.

[0100] According to the hydraulic pressure prediction control method of an automotive brake wheel cylinder according to an embodiment of the present invention, this method uses predictive control to obtain the switching state vector of the inlet valve and the outlet valve at the current moment, cancels the PWM generator module in the classical PWM control mode, reduces the complexity of the control structure and cost of the hydraulic pressure control of the brake wheel cylinder; at the same time, a direct quantitative relationship between the hydraulic pressure of the brake wheel cylinder and the switching state vector of the inlet valve and the outlet valve is established, and through model prediction and cost function optimization, the optimal switching control of the inlet valve and the outlet valve can be obtained.

[0101] To implement the above embodiment, Figure 3 As shown, in this embodiment, a hydraulic pressure prediction control system for an automotive brake wheel cylinder is further provided. The system includes a data processing module 81, a wheel cylinder hydraulic pressure model module 82, a disturbance observation module 83, a hydraulic pressure prediction model module 84, a hydraulic pressure cost function module 85, an optimal hydraulic pressure vector calculation module 86, and a building module 87. Among them,

[0102] The data processing module 81 is configured to obtain the operation data of the hydraulic braking system after initializing in response to the power-on of the hydraulic braking system. Among them, the operation data includes the hydraulic pressure of the brake wheel cylinder.

[0103] The data processing module 81 is further configured to obtain a hydraulic pressure vector control set of the brake wheel cylinder based on the operation data.

[0104] The building module 87 is configured to establish a prediction equation of the hydraulic pressure of the brake wheel cylinder based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder.

[0105] The hydraulic pressure cost function module 85 is configured to construct a cost function for the hydraulic pressure control of the brake wheel cylinder based on the prediction equation of the hydraulic pressure of the brake wheel cylinder.

[0106] The optimal hydraulic pressure vector calculation module 86 is configured to obtain the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve based on the cost function, and realize the adjustment of the hydraulic pressure of the brake wheel cylinder through the cooperation of the inlet valve and the outlet valve according to the optimal state vectors.

[0107] Further, the above data processing module 81 is specifically configured to:

[0108] Construct a state vector set of the inlet valve and the outlet valve and a hydraulic pressure vector control set of the brake wheel cylinder according to the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, and the combined switch states of the inlet valve and the outlet valve.

[0109] Further, the above building module 87 further includes a wheel cylinder hydraulic pressure model module 82, a disturbance observation module 83, and a hydraulic pressure prediction model module 84. Among them,

[0110] The wheel cylinder hydraulic pressure model module 82 is used to obtain the discrete state - space equation of the hydraulic pressure based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder;

[0111] The disturbance observation module 83 is used to estimate the lumped disturbance term of the brake wheel cylinder in real - time and obtain the estimated value of the lumped disturbance term;

[0112] The hydraulic pressure prediction model module 84 is used to establish the prediction equation of the brake wheel cylinder hydraulic pressure based on the estimated value of the lumped disturbance term and the discrete state - space equation.

[0113] In an embodiment of the present invention, the above - mentioned wheel cylinder hydraulic pressure model module 82 is specifically used for:

[0114] Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establish the dynamic hydraulic pressure equation of the brake wheel cylinder;

[0115] Convert the dynamic hydraulic pressure equation of the brake wheel cylinder into a state - space equation;

[0116] Discretize the state - space equation to obtain the discrete state - space equation of the hydraulic pressure.

[0117] According to the hydraulic pressure prediction control system of the automotive brake wheel cylinder in the embodiment of the present invention, the system uses predictive control to obtain the switch state vector of the inlet valve and the outlet valve at the current moment, cancels the PWM generator module in the classical PWM control mode, reduces the complexity of the control structure and cost of the brake wheel cylinder hydraulic pressure control; meanwhile, a direct quantitative relationship between the brake wheel cylinder hydraulic pressure and the switch state vector of the inlet valve and the outlet valve is established. Through model prediction and cost - function optimization, the optimal switch control of the inlet valve and the outlet valve can be obtained.

[0118] To implement the above - mentioned embodiment, the present invention proposes a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it can implement the above - mentioned Figure 2 shown method.

[0119] To implement the above - mentioned embodiment, the present invention proposes a computer storage medium, wherein the computer storage medium stores computer - executable instructions; after the computer - executable instructions are executed by the processor, the above - mentioned Figure 2 shown method can be implemented.

[0120] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0121] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

Claims

1. A method for predicting and controlling the hydraulic pressure of a vehicle brake wheel cylinder, characterized in that: The method is applied to an automotive hydraulic braking system and includes: After initializing in response to the power-on of the hydraulic braking system, obtaining the operating data of the hydraulic braking system, where the operating data includes the hydraulic pressure of the brake wheel cylinder; Based on the operating data, obtaining the hydraulic pressure vector control set of the brake wheel cylinder; Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establishing a prediction equation for the hydraulic pressure of the brake wheel cylinder; Based on the prediction equation of the hydraulic pressure of the brake wheel cylinder, constructing a cost function for controlling the hydraulic pressure of the brake wheel cylinder; Based on the cost function, obtaining the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve, and adjusting the hydraulic pressure of the brake wheel cylinder by the cooperation of the inlet valve and outlet valve according to the optimal state vectors.

2. The method according to claim 1, characterized in that The operating data includes the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, the hydraulic pressure of the brake wheel cylinder, and the combined switch states of the inlet valve and outlet valve. Based on the operating data, obtaining the hydraulic pressure vector control set of the brake wheel cylinder includes: constructing a state vector set of the inlet valve and outlet valve and the hydraulic pressure vector control set of the brake wheel cylinder according to the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, and the combined switch states of the inlet valve and outlet valve.

3. The method according to claim 2, characterized in that Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establishing a prediction equation for the hydraulic pressure of the brake wheel cylinder includes: Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, obtaining the discrete state space equation of the hydraulic pressure; Real-time estimating the lumped disturbance term of the brake wheel cylinder to obtain an estimated value of the lumped disturbance term; Based on the estimated value of the lumped disturbance term and the discrete state space equation, establishing a prediction equation for the hydraulic pressure of the brake wheel cylinder.

4. The method according to claim 3, wherein Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, obtaining the discrete state space equation of the hydraulic pressure includes: Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establishing a dynamic hydraulic pressure equation of the brake wheel cylinder; Converting the dynamic hydraulic pressure equation of the brake wheel cylinder into a state space equation; Discretizing the state space equation to obtain the discrete state space equation of the hydraulic pressure.

5. A hydraulic pressure prediction control system for an automotive brake wheel cylinder, characterized in that, The system is applied to an automotive hydraulic braking system. The system includes a data processing module, an establishment module, a hydraulic pressure cost function module, and an optimal hydraulic pressure vector calculation module, where The data processing module is configured to obtain the operating data of the hydraulic braking system after initializing in response to the power-on of the hydraulic braking system, where the operating data includes the hydraulic pressure of the brake wheel cylinder; The data processing module is further configured to obtain the hydraulic pressure vector control set of the brake wheel cylinder based on the operating data; The establishment module is configured to establish a prediction equation for the hydraulic pressure of the brake wheel cylinder based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder; The hydraulic pressure cost function module is configured to construct a cost function for controlling the hydraulic pressure of the brake wheel cylinder based on the prediction equation of the hydraulic pressure of the brake wheel cylinder; The optimal hydraulic pressure vector calculation module is used to obtain the optimal hydraulic pressure vector of the brake wheel cylinder and the optimal state vectors of the corresponding inlet valve and outlet valve based on the cost function, and the inlet valve and outlet valve cooperate according to the optimal state vectors to achieve the hydraulic pressure regulation of the brake wheel cylinder.

6. The system according to claim 5, characterized in that, The operation data includes the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, the hydraulic pressure of the brake wheel cylinder, and the combined switch states of the inlet valve and outlet valve. The data processing module is specifically used for: Construct a state vector set of the inlet valve and outlet valve and a hydraulic pressure vector control set of the brake wheel cylinder according to the hydraulic pressure of the high-pressure supply unit, the hydraulic pressure of the low-pressure oil return unit, and the combined switch states of the inlet valve and outlet valve.

7. The system according to claim 5, characterized in that The establishment module further includes a wheel cylinder hydraulic pressure model module, a disturbance observation module, and a hydraulic pressure prediction model module, where The wheel cylinder hydraulic pressure model module is used to obtain the discrete state space equation of the hydraulic pressure based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder. The disturbance observation module is used to estimate the lumped disturbance term of the brake wheel cylinder in real time to obtain an estimated value of the lumped disturbance term. The hydraulic pressure prediction model module is used to establish a prediction equation of the brake wheel cylinder hydraulic pressure based on the estimated value of the lumped disturbance term and the discrete state space equation.

8. The system according to claim 7, wherein The wheel cylinder hydraulic pressure model module is specifically used for: Based on the hydraulic pressure vector control set and the hydraulic pressure of the brake wheel cylinder, establish a dynamic hydraulic pressure equation of the brake wheel cylinder. Convert the dynamic hydraulic pressure equation of the brake wheel cylinder into a state space equation. Perform discretization processing on the state space equation to obtain the discrete state space equation of the hydraulic pressure.

9. A computer device, characterized in that, It includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it can implement the method described in any one of claims 1-4.

10. A computer storage medium, wherein, The computer storage medium stores computer-executable instructions; after the computer-executable instructions are executed by the processor, the method described in any one of claims 1-4 can be implemented.

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