A method and device for distributing active radial bogie control quantities for a rail vehicle

Abstract

The present application relates to a kind of rail vehicle active radial bogie control quantity distribution method and equipment, method includes: obtaining the feedforward information of bogie, constructs the dynamics model of bogie;Obtain actuator displacement feedback information and actuator output force feedback information, according to actuator displacement feedback information and actuator output force feedback information wheel longitudinal force estimation calculation, obtain the traction or braking force on wheel circumference;Based on actuator displacement feedback information and the traction or braking force on wheel circumference, and in combination with the dynamics model of bogie, solve the optimal value of wheel set head angle when the curve passing performance of bogie is optimal;According to traction or braking force, actuator output force feedback and the optimal value of wheel set head angle, in combination with the optimization model of pre-construction, solve the displacement value of each actuator when objective function takes minimum value.Compared with prior art, the present application has the advantages such as balanced the output force of each actuator.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a method and device for allocating control quantities of an active radial bogie for a rail vehicle. Background Technology

[0002] A vehicle bogie is an independent running gear consisting of two or more pairs of wheelsets connected by a frame or other device, capable of rotating relative to the car body, and equipped with springs and other components. Depending on the vehicle's gross weight, the car body is supported on two or more bogies. Most vehicles have a running gear consisting of two two-axle bogies, while a few vehicles use three-axle bogies, and some long and heavy-duty trucks have four, six, or eight bogies. The more axles, the greater the vehicle's load capacity.

[0003] There is a strong coupling constraint between the active radial function of the bogie and the bogie's traction, braking, and suspension functions. However, current active radial control methods only treat the active radial system as an independent system and lack consideration of the above coupling constraints, making the control strategy unsuitable for actual scenarios.

[0004] For example, Chinese patent CN108248628A discloses an active radial bogie and its control method, including a data acquisition system, a data processing control system, and a steering execution system. The data processing control system is connected to both the data acquisition system and the steering execution system. The data acquisition system collects track data of the current train and transmits the collected data to the data processing control system. The data processing control system processes the collected data and then controls the steering execution system to actively steer, enabling the active radial bogie to adapt to the train speed and the track ahead for steering. However, it does not consider the coordinated operation of active radial control and traction braking, resulting in uneven output forces from the various actuators. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art, which does not consider the coordinated operation of active radial control and traction braking, and the output force of each actuator is not balanced, and to provide a method and device for the distribution of active radial bogie control for rail vehicles.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A method for allocating control parameters for an active radial bogie of a rail vehicle includes the following steps:

[0008] Obtain the feedforward information of the bogie and construct a dynamic model of the bogie;

[0009] Obtain actuator displacement feedback information and actuator output force feedback information, and perform wheel longitudinal force estimation calculation based on the actuator displacement feedback information and actuator output force feedback information to obtain wheel circumferential traction force or braking force.

[0010] Based on actuator displacement feedback information and wheel circumference traction or braking force, and combined with the bogie dynamic model, the optimal wheel yaw angle value when the bogie curve passes through the optimal performance is solved.

[0011] Based on the feedback of wheel traction or braking force, actuator output force, and optimal wheel yaw angle, the displacement of each actuator is calculated when the objective function is minimized using a pre-built optimization model.

[0012] Furthermore, the objective function of the pre-built optimization model is expressed as:

[0013]

[0014] In the formula, x ui This is the actuator displacement command. x is the optimal yaw angle of the wheelset calculated by the control layer. ai For actuator displacement feedback, F ai For actuator output force feedback, k x q is the longitudinal stiffness of the primary suspension, b is half the lateral span between two actuators on the same axle, and q is the longitudinal stiffness of the primary suspension. x With q f Here, represents the weighting coefficients, and E is the symbol for the objective function.

[0015] Furthermore, by applying the constraints of the actuator, the minimum value of the objective function is obtained, thus yielding the displacement command of the actuator.

[0016] Furthermore, the constraints of the actuator include the maximum output force of the actuator, the maximum displacement of the actuator, and the maximum speed of the actuator.

[0017] Furthermore, the feedforward information of the bogie includes the curve radius and curve superelevation information of the bogie.

[0018] Furthermore, in the process of obtaining the optimal yaw angle, the goal is to optimize the bogie curve passing performance, and the constraints between the bogie and the traction and braking functions are considered. The optimal yaw angle of the wheelset is obtained by solving a constrained optimization problem.

[0019] Furthermore, the actuator is equipped with a displacement sensor, which is used to acquire displacement feedback information of the actuator.

[0020] Furthermore, the actuator is equipped with a force sensor, which is used to obtain the output force feedback information of the actuator.

[0021] This solution also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the program to implement the above-described method.

[0022] This solution also provides a computer-readable storage medium on which a computer program is stored, the computer program being executed by a processor using the method described above.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. To address the technical challenge of coordinating the active radial control with traction and braking functions of the bogie, this solution's control layer uses feedforward information from the bogie and feedback information from the actuators to solve an optimization function aimed at minimizing bogie wear. This yields the optimal yaw angle of the wheelset, reducing wear during each bogie turn and extending the lifespan of the device. The distribution layer uses the optimal yaw angle of the wheelset and the overdrive characteristics of the actuators to obtain the optimal displacement solution for each actuator, enabling the distribution of actuator control quantities. This allows for automatic adjustment of the output displacement of each actuator under traction and braking conditions, balancing the output force of each actuator.

[0025] 2. Based on the distribution effect of the actuators, the distribution layer of this scheme also takes into account the balance of the output force of each actuator, so that the distribution layer has a coordinated distribution function. When there is traction or braking force on the wheel at the same time, the distribution layer can coordinate and distribute the displacement command of each actuator, so that the output force of each actuator is as close as possible, without increasing the load of any actuator. Attached Figure Description

[0026] Figure 1 A schematic diagram of the active radial bogie control quantity allocation method for rail vehicles provided by the present invention;

[0027] Figure 2 The diagram shows the structure of the active radial bogie provided by this invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0030] Example 1

[0031] like Figure 1 As shown, a method for allocating control quantities for an active radial bogie of a rail vehicle includes the following steps:

[0032] Obtain the feedforward information of the bogie and construct a dynamic model of the bogie;

[0033] Obtain actuator displacement feedback information and actuator output force feedback information, and perform wheel longitudinal force estimation calculation based on the actuator displacement feedback information and actuator output force feedback information to obtain wheel circumferential traction force or braking force.

[0034] The optimal value of the wheelset yaw angle is solved based on the actuator displacement feedback information and the wheel circumference traction or braking force, combined with the dynamic model of the bogie.

[0035] Based on the optimal values ​​of wheel circumference traction or braking force and wheel yaw angle, the minimum displacement of the actuator is solved using a pre-built optimization model.

[0036] To address the technical challenge of coordinating the active radial control with traction and braking functions of the bogie, this solution's control layer uses feedforward information from the bogie and feedback information from the actuators to solve an optimization function aimed at minimizing bogie wear. This yields the optimal yaw angle of the wheelset, reducing wear during each bogie turn and extending the lifespan of the device. The distribution layer, based on the optimal yaw angle of the wheelset and the overdrive characteristics of the actuators, obtains the optimal displacement solution for each actuator, enabling the distribution of actuator control quantities. This allows for automatic adjustment of the output displacement of each actuator under traction and braking conditions, balancing the output force of each actuator.

[0037] The controller includes a control layer and an allocation layer. The control layer is used to solve for the optimal yaw angle of the wheelset, and the allocation layer is used to solve for the displacement command of the actuator.

[0038] Specifically, the objective function of the constructed optimization model is expressed as:

[0039]

[0040] In the formula, x ui This is the actuator displacement command. x is the optimal yaw angle of the wheelset calculated by the control layer. ai For actuator displacement feedback, Fai For actuator output force feedback, k x q is the longitudinal stiffness of the primary suspension, b is half the lateral span between two actuators on the same axle, and q is the longitudinal stiffness of the primary suspension. x With q f Here, represents the weighting coefficients, and E is the symbol for the objective function.

[0041] The objective function takes the optimal wheel yaw angle calculated by the control layer, the actual displacement feedback of each actuator, and the actual output force feedback of each actuator as inputs, and the motion displacement command of each actuator as outputs, which can realize the coordination of active radial control and traction and braking functions.

[0042] In solving the objective function, the minimum value of the objective function is obtained through the actuator's constraints, thus yielding the actuator's displacement command. The actuator's constraints include its maximum output force, maximum displacement, and maximum speed.

[0043] The first term of the objective function reflects the distribution effect, while the second term is a performance function describing the balance of output forces of each actuator. By introducing the balance of output forces of each actuator in the second term, the distribution layer has a coordinated distribution function: when there is traction or braking force on the wheel at the same time, the distribution layer can coordinate and distribute the displacement commands of each actuator, so that the output forces of each actuator are as similar as possible, without increasing the load of any actuator.

[0044] Specifically, the feedforward information for the bogie includes the bogie's curve radius and curve superelevation information.

[0045] In the process of finding the optimal yaw angle, the goal is to optimize the bogie's curve-passing performance, and the constraints between the bogie and the traction and braking functions are considered. The optimal yaw angle of the wheelset is obtained by solving a constrained optimization problem.

[0046] The actuator is equipped with a displacement sensor, which is used to obtain displacement feedback information of the actuator.

[0047] The actuator is equipped with a force sensor, which is used to obtain the output force feedback information of the actuator.

[0048] In this embodiment, each axle of the active radial bogie is equipped with two actuators, which means that there are two controllable degrees of freedom for each target degree of freedom. Therefore, the active radial bogie has overdrive characteristics.

[0049] like Figure 1-2 As shown, combining the above-mentioned method for allocating the active radial bogie control quantity of rail vehicles and its specific implementation, the optimal implementation method of this scheme is determined as follows:

[0050] 1. First, a bogie dynamics model is established, and then a controller with a two-layer control-distribution structure is built. The optimal yaw angle of the wheelset is calculated in the control layer; in the distribution layer, based on the overdrive characteristics of the active radial bogie, the distribution from the wheelset yaw angle to the actuator displacement is completed. The objective function of one distribution layer is as follows:

[0051]

[0052] Where x ui This is the actuator displacement command. x is the optimal yaw angle of the wheelset calculated by the control layer. ai For actuator displacement feedback, F ai For actuator output force feedback, k x q represents the longitudinal stiffness of the primary suspension, and b is half the lateral span between two actuators on the same axle. x With q f The weighting coefficients are used. The objective function takes the optimal wheelset yaw angle calculated by the control layer, the actual displacement feedback of each actuator, and the actual output force feedback of each actuator as inputs, and the motion displacement command of each actuator as output. It can achieve coordination between active radial control and traction / braking functions. When solving this optimization problem, constraints such as the maximum output force of the actuator, the maximum motion displacement of the actuator, and the maximum motion speed of the actuator must be considered.

[0053] 2. The first term of the objective function reflects the distribution effect, while the second term is a performance function describing the balance of output force among the actuators. The introduction of the second term enables the distribution layer to have a coordinated distribution function: when traction or braking forces exist simultaneously on the wheels, the distribution layer can coordinate and distribute the displacement commands of each actuator, making the output forces of each actuator as similar as possible without additionally increasing the load on any particular actuator.

[0054] 3. The control layer aims to optimize the bogie's curve-passing performance and considers the constraints between the bogie and the traction and braking functions. It obtains the optimal yaw angle of the wheelset by solving a constrained optimization problem.

[0055] 4. Actuator displacement feedback x ai Actuator output force feedback F ai Data is obtained from displacement sensors and force sensors installed on the actuator, respectively.

[0056] Furthermore, the essence of active radial control is to control the yaw motion of the wheelset. Figure 2 The active radial bogie shown is equipped with two actuators for each axle, which means that for each target degree of freedom, there are two controllable degrees of freedom. This illustrates that... Figure 2The illustrated active radial bogie exhibits overdrive characteristics. When active radial control is applied to the wheelset, the wheelset is subjected to a longitudinal force F. A and suspension reaction force F S If the bogie is in a traction or braking state, the wheelset is also subjected to a longitudinal force F. TB .

[0057] Based on feedforward and feedback information, combined with the bogie dynamics model, and considering the constraints between the bogie and traction and braking functions, the control layer obtains the optimal yaw angle of the wheelset by solving an optimization problem.

[0058] In the allocation layer, the optimal yaw angle of the wheelset, the actual displacement feedback of the actuator, and the actual output force feedback of the actuator calculated by the control layer are used as inputs, and the actuator action displacement command is used as output. Considering the constraints such as the maximum output force of the actuator, the maximum action displacement of the actuator, and the maximum action speed of the actuator, an optimization problem is solved to obtain the displacement command of each actuator.

[0059] This embodiment also provides a specific case of determining the displacement of each actuator according to this scheme, and demonstrates the scheme.

[0060] Combination Figure 2 As shown, assuming the bogie is running at a balanced speed on a circular curve in a coasting state, after active radial control, x a1 =x a4 =4mm, x a2 =x a3 = -4mm, at this point all wheelsets are in the ideal radial position, that is, the wheelset center is on the pure rolling line, the angle of attack is zero, and there is no longitudinal or lateral creep force. Suspension parameter k x =10MN / m, the output force of each actuator at this time can be calculated as: F A1 =F A2 =F A3 =F A4 =40kN.

[0061] Braking is applied at a certain moment, at which time F TB1 =F TB2 =F TB3 =F TB4 = -10kN. If, at this point, coordination control is not performed based on the longitudinal force, and the actuator's displacement command remains unchanged, then according to the above formula, F can be calculated as follows: A1 =F A4 =50kN, F A2 =F A3= -30kN. It can be seen that the output force of actuators 1 and 4 increases to 50kN. This is because, under displacement control, in order to achieve a 4mm displacement, braking force needs to be overcome. At the same time, the output force of actuators 2 and 3 decreases to 30kN. This results in an imbalance in the output force of each actuator.

[0062] However, in the method proposed in this scheme, the aforementioned braking force is estimated by the wheel longitudinal force estimation module. Then, under the coordinating effect of the distribution layer, the same radial effect can be achieved while balancing the output forces of the four actuators. That is, x a1 =x a4 =3mm, x a2 =x a3 = -5mm, at this time F A1 =F A4 =40kN, F A2 =F A3 = -40kN. This is a function that existing control technology does not have.

[0063] The electronic device of this invention includes a central processing unit (CPU), which can perform various appropriate actions and processes according to computer program instructions stored in read-only memory (ROM) or loaded from a storage unit into random access memory (RAM). The RAM may also store various programs and data required for device operation. The CPU, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0064] Multiple components in the device are connected to the I / O interface, including: input units such as keyboards and mice; output units such as various types of displays and speakers; storage units such as disks and optical discs; and communication units such as network interface cards (NICs), modems, and wireless transceivers. The communication unit allows the device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0065] The processing unit executes the various methods and processes described above, such as the active radial bogie control allocation method for rail vehicles of the present invention. For example, in some embodiments, the active radial bogie control allocation method for rail vehicles of the present invention may be implemented as a computer software program tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program may be loaded and / or installed on the device via ROM and / or a communication unit. When the computer program is loaded into RAM and executed by the CPU, one or more steps of the active radial bogie control allocation method for rail vehicles of the present invention described above may be performed. Alternatively, in other embodiments, the CPU may be configured to execute the active radial bogie control allocation method for rail vehicles of the present invention by any other suitable means (e.g., by means of firmware).

[0066] In the context of this invention, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. Machine-readable media can include, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0067] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for allocating control quantities for an active radial bogie of a rail vehicle, characterized in that, Includes the following steps: Obtain the feedforward information of the bogie and construct a dynamic model of the bogie; Obtain actuator displacement feedback information and actuator output force feedback information, and perform wheel longitudinal force estimation calculation based on the actuator displacement feedback information and actuator output force feedback information to obtain wheel circumferential traction force or braking force. Based on actuator displacement feedback information and wheel circumference traction or braking force, and combined with the bogie dynamic model, the optimal wheel yaw angle value when the bogie curve passes through the optimal performance is solved. Based on the feedback of wheel circumference traction or braking force, actuator output force, and optimal wheel yaw angle, the displacement of each actuator is calculated when the objective function is minimized using a pre-built optimization model. The objective function of the pre-built optimization model is expressed as: In the formula, This is the actuator displacement command. The optimal yaw angle of the wheelset is calculated by the control layer. For actuator displacement feedback, For actuator output force feedback, The longitudinal stiffness of the primary suspension system. It is half the lateral span between two actuators on the same axle. and Here, represents the weighting coefficients, and E is the symbol for the objective function.

2. The method for allocating control quantities for an active radial bogie of a rail vehicle according to claim 1, characterized in that, By finding the minimum value of the objective function based on the constraints of the actuator, the displacement command of the actuator can be obtained.

3. The method for allocating control quantities for an active radial bogie of a rail vehicle according to claim 2, characterized in that, The constraints on the actuator include the maximum output force constraint, the maximum displacement constraint, and the maximum speed constraint.

4. The method for allocating control quantities for an active radial bogie of a rail vehicle according to claim 1, characterized in that, The feedforward information for the bogie includes the bogie's curve radius and curve superelevation information.

5. The method for allocating control quantities for an active radial bogie of a rail vehicle according to claim 1, characterized in that, In the process of obtaining the optimal yaw angle, the goal is to optimize the bogie's curve-passing performance, and the constraints between the bogie and the traction and braking functions are considered. The optimal yaw angle of the wheelset is obtained by solving a constrained optimization problem.

6. The method for allocating control quantities for an active radial bogie of a rail vehicle according to claim 1, characterized in that, The actuator is equipped with a displacement sensor, which is used to obtain displacement feedback information of the actuator.

7. The method for allocating control quantities for an active radial bogie of a rail vehicle according to claim 1, characterized in that, The actuator is equipped with a force sensor, which is used to obtain the output force feedback information of the actuator.

8. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which is executed by a processor according to any one of claims 1 to 7.

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