Fault-tolerant control method and device for active radial bogie of railway vehicle

Abstract

The application relates to a kind of track vehicle active radial bogie fault-tolerant control method and device, comprising the following steps: obtaining actuator displacement feedback information;Obtain the feedforward information of bogie, construct the dynamics model of bogie;Based on the dynamics model of bogie, with the lowest wheel pair wear number as optimization target, under the first constraint condition, the optimal head angle of front and rear wheel pair is obtained by optimization algorithm;Receive the optimal head angle of front and rear wheel pair and actuator displacement feedback information, based on pre-constructed objective function, under the second constraint condition, the optimal value of actuator displacement is solved.Compared with prior art, the application has the advantages of realizing active fault-tolerant control after actuator failure and the like.

Description

Technical Field

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

[0002] The active radial control system consists of a controller, sensors, actuators, and the controlled object. Each component of this complex system is susceptible to failure. In particular, if the actuators, which directly determine the bogie's running attitude, fail, the operational safety of the rail vehicle may be jeopardized if the malfunction is not controlled. Therefore, specific measures are needed to address potential actuator failures, ensuring that the bogie's radial control performance still meets operational requirements even after actuator malfunction.

[0003] Existing technologies, when actuators malfunction, control them by reconstructing the control law or switching the control module to a backup control algorithm for actuator malfunctions. However, the passive control method of actively switching control cannot take timely measures to address actuator malfunctions and ensure the safety of rail vehicles. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology, which relies on reconstructing the control law of the actuator or switching the control module to a backup control algorithm when the actuator fails, and the passive control of the active switching control method, which cannot take timely measures to address actuator failures and ensure the safety of the rail vehicle. Therefore, this invention provides an active radial bogie fault-tolerant control method for rail vehicles.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A fault-tolerant control method for an active radial bogie of a rail vehicle includes the following steps:

[0007] Obtain actuator displacement feedback information; obtain bogie feedforward information and construct a dynamic model of the bogie;

[0008] Based on the dynamic model of the bogie, with the minimum wheelset wear number as the optimization objective, the optimal yaw angle of the front and rear wheelsets is obtained by an optimization algorithm under the first constraint.

[0009] Receive the optimal yaw angle of the front and rear wheelsets and the actuator displacement feedback information. Based on the pre-constructed objective function, under the second constraint condition, solve for the optimal displacement value of the actuator.

[0010] Furthermore, the pre-constructed objective function is expressed as:

[0011]

[0012] In the formula, x ui For actuator displacement command, x ai For actuator displacement feedback, The optimal yaw angle of the wheelset is calculated by the control layer, b is half the lateral span of the coaxial actuator, and q is the yaw angle of the wheelset. x With q a Here, represents the weighting coefficients, and E is the symbol for the objective function.

[0013] Furthermore, the constraints of the actuator include the maximum output force constraint, the maximum displacement constraint, and the maximum speed constraint.

[0014] Furthermore, the actuator is equipped with a displacement sensor to obtain displacement feedback information of the actuator.

[0015] Furthermore, in the process of determining the optimal yaw angle, the minimum yaw angle of the wheelset is obtained by taking the optimal performance of the bogie curve as the objective and combining the constraints between the bogie and the traction and braking functions.

[0016] This solution also provides a fault-tolerant control device for an active radial bogie of a rail vehicle, including:

[0017] The data acquisition module is configured to: acquire actuator displacement feedback information; acquire bogie feedforward information and construct a dynamic model of the bogie;

[0018] The first optimization module is configured to: based on the dynamic model of the bogie, with the minimum wheelset wear number as the optimization objective, and under the first constraint, solve for the optimal yaw angle of the front and rear wheelsets through an optimization algorithm;

[0019] The second optimization module is configured to receive the optimal yaw angle of the front and rear wheelsets and the actuator displacement feedback information, and, based on the pre-constructed objective function, solve for the optimal displacement value of the actuator under the second constraint.

[0020] Furthermore, the objective function of the second optimization module is expressed as:

[0021]

[0022] In the formula, x ui For actuator displacement command, x ai For actuator displacement feedback, The optimal yaw angle of the wheelset is calculated by the control layer, b is half the lateral span of the coaxial actuator, and q is the yaw angle of the wheelset. x With q a Here, represents the weighting coefficients, and E is the symbol for the objective function.

[0023] Furthermore, the constraints of the actuator include the maximum output force constraint, the maximum displacement constraint, and the maximum speed constraint.

[0024] Furthermore, the actuator is equipped with a displacement sensor to obtain displacement feedback information of the actuator.

[0025] Furthermore, the first optimization module aims to achieve optimal bogie curve passing performance, and, in conjunction with the constraints between the bogie and traction and braking functions, solves for the minimum yaw angle of the wheelset.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] (1) In this scheme, based on the displacement feedback of the actuator and the feedforward information of the bogie, the optimal yaw angle of the wheelset is obtained with the goal of minimizing the wear number of the wheelset. Then, based on the optimal yaw angle of the wheelset and the displacement feedback of the actuator, the displacement command of the actuator is determined, realizing the redistribution of the actuator control quantity under fault mode, so as to realize active fault-tolerant control after the actuator failure, so that the actual controlled yaw angle of the wheelset still meets the requirements of radial control. More importantly, after the system fails, the bogie will not be allowed to have an excessive or reverse radial working state, thus ensuring the safe operation of the bogie.

[0028] (2) The objective function of the second optimization module in this scheme includes the allocation effect of the actuator control quantity and the actual execution state of the actuator. Because the actual execution state of the actuator is designed, the allocation layer has a fault tolerance function: when the actuator fails, the allocation layer can allocate the displacement command of each actuator according to the same model, thus avoiding the reconstruction of the control law or the switching of the algorithm after the failure. Attached Figure Description

[0029] Figure 1 A schematic diagram illustrating the principle of the bogie fault-tolerant control method provided by this invention;

[0030] Figure 2 A schematic diagram of the structure of the active radial bogie provided by the present invention. Detailed Implementation

[0031] 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.

[0032] 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.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0034] Example 1

[0035] like Figure 1-2 As shown, this embodiment provides a fault-tolerant control method for an active radial bogie of a rail vehicle, including the following steps:

[0036] Obtain actuator displacement feedback information; obtain bogie feedforward information and construct a dynamic model of the bogie;

[0037] Based on the dynamic model of the bogie, with the minimum wheelset wear number as the optimization objective, the optimal yaw angle of the front and rear wheelsets is obtained by an optimization algorithm under the first constraint.

[0038] Receive the optimal yaw angle of the front and rear wheelsets and the actuator displacement feedback information. Based on the pre-constructed objective function, under the second constraint condition, solve for the optimal displacement value of the actuator.

[0039] Based on the displacement feedback of the actuator and the feedforward information of the bogie, the optimal yaw angle of the wheelset is obtained with the goal of minimizing the wheelset wear number. Then, based on the optimal yaw angle of the wheelset and the displacement feedback of the actuator, the displacement command of the actuator is determined, realizing the redistribution of the actuator control quantity under fault mode, so as to achieve active fault-tolerant control after the actuator failure, ensuring that the actual controlled yaw angle of the wheelset still meets the requirements of radial control. More importantly, after the system fails, the bogie will not be subjected to excessive or reverse radial adverse working conditions, thus ensuring the safe operation of the bogie.

[0040] Preferably, the pre-constructed objective function is expressed as:

[0041]

[0042] In the formula, x ui For actuator displacement command, x ai For actuator displacement feedback, The optimal yaw angle of the wheelset is calculated by the control layer, b is half the lateral span of the coaxial actuator, and q is the yaw angle of the wheelset. x With q aHere, E represents the weighting coefficients, and E is the symbol for the objective function. This objective function takes the optimal wheelset yaw angle calculated by the control layer and the actual displacement feedback of each actuator as input, and the motion displacement command of each actuator as output, which can realize active fault-tolerant control after actuator failure.

[0043] The pre-built objective function includes the allocation effect of actuator control quantities and the actual execution state of the actuator. Because the actual execution state of the actuator is designed, the allocation layer has a fault tolerance function: when the actuator fails, the allocation layer can allocate the displacement commands of each actuator according to the same model, thus avoiding control law reconstruction or algorithm switching after the failure.

[0044] In this embodiment, the actuator is equipped with a displacement sensor to obtain displacement feedback information of the actuator.

[0045] Specifically, the second set of constraints includes the actuator's maximum output force constraint, the actuator's maximum displacement constraint, and the actuator's maximum velocity constraint. By combining these constraints with a pre-constructed objective function, the optimal displacement command of the actuator is obtained.

[0046] Specifically, in the process of finding the optimal yaw angle, the optimization objectives are to minimize the bogie curve passing performance and the wheelset wear number. By combining the constraints between the bogie and the traction and braking functions, the minimum yaw angle of the wheelset is obtained.

[0047] This solution also provides a fault-tolerant control device for an active radial bogie of a rail vehicle, including:

[0048] The data acquisition module is configured to: acquire actuator displacement feedback information; acquire bogie feedforward information and construct a dynamic model of the bogie;

[0049] The first optimization module is configured to: based on the dynamic model of the bogie, with the minimum wheelset wear number as the optimization objective, and under the first constraint, solve for the optimal yaw angle of the front and rear wheelsets through an optimization algorithm;

[0050] The second optimization module is configured to receive the optimal yaw angle of the front and rear wheelsets and the actuator displacement feedback information, and, based on the pre-constructed objective function, solve for the optimal displacement value of the actuator under the second constraint.

[0051] Furthermore, the objective function of the second optimization module is expressed as:

[0052]

[0053] In the formula, x ui For actuator displacement command, x ai For actuator displacement feedback The optimal yaw angle of the wheelset is calculated by the control layer, b is half the lateral span of the coaxial actuator, and q is the yaw angle of the wheelset. x With q a Here, represents the weighting coefficients, and E is the symbol for the objective function.

[0054] Furthermore, by applying the constraints of the actuator, the minimum value of the objective function of the allocation layer is obtained to determine the displacement of the actuator.

[0055] Furthermore, the constraints on the actuator include the maximum output force constraint, the maximum displacement constraint, and the maximum speed constraint.

[0056] Furthermore, the first optimization module aims to achieve the best performance in bogie curve passage, and, in conjunction with the constraints between the bogie and the traction and braking functions, solves for the minimum yaw angle of the wheelset.

[0057] In conjunction with the above, this implementation also provides a specific set of steps including the following:

[0058] 1. First, a bogie dynamics model is established, and then a fault-tolerant 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. A possible objective function for the distribution layer is as follows:

[0059]

[0060] Where x ui For actuator displacement command, x ai For actuator displacement feedback q represents the optimal yaw angle of the wheelset calculated by the control layer, where b is half the lateral span of the coaxial actuator. x With q a The weighting coefficients are used. The objective function takes the optimal wheelset yaw angle calculated by the control layer and the actual displacement feedback of each actuator as input, and the motion displacement command of each actuator as output, which can realize active fault-tolerant control after actuator failure.

[0061] 2. The first term of the objective function reflects the allocation effect, while the second term is a cost function describing the actual execution state. The introduction of the second term enables the allocation layer to have fault tolerance: when an actuator fails, the allocation layer can allocate displacement commands to each actuator according to the same model, thus avoiding control law reconstruction or algorithm switching after a failure.

[0062] 3. The control layer aims to optimize the bogie's curve-passing performance by solving an optimization problem to obtain the optimal yaw angle of the wheelset.

[0063] 4. Actuator displacement feedback x ai It is obtained by a displacement sensor installed on the actuator.

[0064] Furthermore, the essence of active radial control is to control the yaw motion of the wheelset, such as... Figure 2 As shown, the active radial bogie is equipped with two actuators for each axle, which means that there are two controllable degrees of freedom for each target degree of freedom. This indicates that the active radial bogie has overdrive characteristics.

[0065] Based on feedforward and feedback information, and combined with the bogie dynamics model, the control layer obtains the optimal yaw angle of the wheelset by solving an optimization problem;

[0066] In the allocation layer, the optimal yaw angle of the wheelset calculated by the control layer is used as input, and the actual displacement feedback of the actuator is used as input. An optimization problem is then solved to obtain the displacement commands of each actuator.

[0067] Let's illustrate this with specific data and examples:

[0068] A) When the bogie is running on a curve, under normal circumstances, the distribution layer calculates the command for actuators 1 and 2 as x based on the optimal yaw angle of the wheelset. u1 =4mm, x u2 = -4mm. However, at a certain moment, actuator No. 1 malfunctioned at 2mm and then self-locked at x. a1 At a position of 2mm, to minimize E, we have x u1 =2mm; correspondingly, x u2 =-6mm. This means that the No. 2 actuator moves a greater displacement, ensuring that the actual controlled yaw angle of the wheelset still meets the radial control requirements. This means that even after an actuator failure, the system's performance can still be effectively maintained. More importantly, it prevents excessive or reverse radial deviations, thus ensuring the safe operation of the bogie.

[0069] B) When the bogie is running on a straight line, under normal circumstances, the distribution layer calculates the command for actuators 1 and 2 as x based on the optimal yaw angle of the wheelset. u1 =0mm,x u2 =0mm. However, at a certain moment, actuator No. 1 malfunctioned and malfunctioned to x. a1 At a position of 5mm, to minimize E, we have x u1 =5mm; correspondingly, x u2=5mm. That is, the displacement of actuator No. 1 on the faulty side is executed by actuator No. 2, so that the actual controlled yaw angle of the wheelset still meets the requirements of radial control. This ensures that after the actuator malfunctions on the active radial bogie on a straight line, the wheelset will not enter a bad working state of excessive or reverse radial movement. This not only avoids additional wear, but also ensures the safe operation of the bogie.

[0070] 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 fault-tolerant control method for an active radial bogie of a rail vehicle, characterized in that, Includes the following steps: Obtain actuator displacement feedback information; obtain bogie feedforward information and construct a dynamic model of the bogie; Based on the dynamic model of the bogie, with the minimum wheelset wear number as the optimization objective, the optimal yaw angle of the front and rear wheelsets is obtained by an optimization algorithm under the first constraint. Receive the optimal yaw angle of the front and rear wheelsets and the actuator displacement feedback information, and solve for the optimal displacement value of the actuator under the second constraint condition based on the pre-constructed objective function. The pre-constructed objective function is expressed as follows: In the formula, This is the actuator displacement command. For actuator displacement feedback The optimal yaw angle of the wheelset is calculated by the control layer. It is half the lateral span of the coaxial actuator. and Here, represents the weighting coefficients, and E is the symbol for the objective function.

2. The fault-tolerant control method for an active radial bogie of a rail vehicle according to claim 1, characterized in that, The second constraint includes the actuator's maximum output force constraint, the actuator's maximum displacement constraint, and the actuator's maximum speed constraint.

3. The fault-tolerant control method for an active radial bogie of a rail vehicle according to claim 1, characterized in that, The actuator is equipped with a displacement sensor to obtain displacement feedback information of the actuator.

4. The fault-tolerant control method for an active radial bogie of a rail vehicle according to claim 1, characterized in that, In the process of determining the optimal yaw angle, the bogie curve passing performance is optimized as the objective, and the minimum yaw angle of the wheelset is obtained by combining the constraints between the bogie and the traction and braking functions.

5. A fault-tolerant control device for an active radial bogie of a rail vehicle, characterized in that, include: The data acquisition module is configured to acquire actuator displacement feedback information. Obtain the feedforward information of the bogie and construct a dynamic model of the bogie; The first optimization module is configured to: based on the dynamic model of the bogie, with the minimum wheelset wear number as the optimization objective, and under the first constraint, solve for the optimal yaw angle of the front and rear wheelsets through an optimization algorithm; The second optimization module is configured to receive the optimal yaw angle of the front and rear wheelsets and the actuator displacement feedback information, and solve for the optimal displacement value of the actuator under the second constraint based on the pre-constructed objective function. The objective function of the second optimization module is expressed as: In the formula, This is the actuator displacement command. For actuator displacement feedback, The optimal yaw angle of the wheelset is calculated by the control layer. It is half the lateral span of the coaxial actuator. and Here, represents the weighting coefficients, and E is the symbol for the objective function.

6. The fault-tolerant control method for an active radial bogie of a rail vehicle according to claim 5, characterized in that, The constraints on the actuator include the maximum output force constraint, the maximum displacement constraint, and the maximum speed constraint.

7. The fault-tolerant control method for an active radial bogie of a rail vehicle according to claim 5, characterized in that, The actuator is equipped with a displacement sensor to obtain displacement feedback information of the actuator.

8. The fault-tolerant control method for an active radial bogie of a rail vehicle according to claim 5, characterized in that, The first optimization module aims to achieve the best performance in bogie curve passage. It combines the constraints between the bogie and the traction and braking functions to solve for the minimum yaw angle of the wheelset.

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