Train dynamics real-time simulation platform

Abstract

A train dynamics real-time simulation platform includes multiple simulation models, each simulation model includes a simulation dynamics calculation unit and an interface unit, the interface unit is used to communicate with the train control system, monitoring system, screen display, etc. of the train to be tested, and the dynamics calculation unit is used to calculate the forces and dynamic performance indicators borne by each vehicle. Its simulation models include: one-dimensional longitudinal dynamics model; one-dimensional semi-physical longitudinal dynamics model; multi-train longitudinal dynamics model; longitudinal dynamics model based on adhesion; three-dimensional semi-physical dynamics model; each dynamic real-time simulation model in the simulation platform is made to simulate the line and train structure as much as possible, meet the needs of various train simulation tests for dynamics simulation environment, and achieve a universal effect.

Description

Technical Field

[0001] The invention relates to the technical field of rail transportation, and in particular to a real-time dynamics simulation platform for trains. Background Art

[0002] Modern railway passenger car systems need to undergo a large number of tests before they are put into operation. Among them, virtual performance testing is a convenient, time-saving, and cost-saving effective testing method, which is a practical and effective supplement to the actual train test. In order to ensure the accuracy of the test and the smooth progress of the test plan, according to the purpose of the test, it is necessary to build a suitable train dynamics model to simulate the scenario of the train system test on the line. Different test items require different dynamic models.

[0003] Patent CN110928272A discloses a method and system for injecting local creep faults of high-speed train wheelsets, and specifically discloses different operating states of wheelsets caused by different creep coefficients under different faults of EMU wheelsets. However, the operating angular velocity of the wheelset in the patent is obtained by converting the mechanical angular velocity output by the motor side through the drive system and wheelset parameters, so it is only applicable to EMU vehicles, and cannot simulate the operating state of the wheelset under local creep faults of high-speed train wheelsets under air braking, and the applicable scenario is single.

[0004] The dynamic model used in the article "Design of Hardware-in-the-Loop Simulation Platform for Wheel Anti-skid System" is a longitudinal dynamic model with creep calculation during the braking process, but the basic starting resistance during the zero-speed traction start of the train is not taken into account, so it is not suitable for the calculation of the train starting process.

[0005] From the above description, it can be seen that the dynamic model currently used in real-time train simulation calculations has the following problems:

[0006] (1) Different tests require different dynamic models. The model exists as a part of the test, not an independent part. It is separated from the existing test environment and is not suitable for other tests.

[0007] (2) The functions of the dynamic model are relatively simple. A single test platform can only realize a single test function and only uses a single type of train dynamic system, which cannot be used as a general dynamic model. Summary of the invention

[0008] The purpose of the present invention is to solve the above technical problems and provide a real-time train dynamics simulation platform integrating multiple dynamic models.

[0009] To achieve the above object, the technical solution adopted by the present invention is:

[0010] A train dynamics real-time simulation platform includes multiple simulation models, each simulation model includes a dynamics calculation unit and an interface unit, the interface unit is used to communicate with the train control system to be tested, and the dynamics calculation unit is used to calculate the force and dynamics performance index borne by each vehicle; the simulation model includes:

[0011] One-dimensional longitudinal dynamics model: Each vehicle in the train has one degree of freedom;

[0012] One-dimensional semi-physical longitudinal dynamics model: Each vehicle in the train has one degree of freedom;

[0013] Multi-train longitudinal dynamics model: includes multiple one-dimensional longitudinal dynamics models, each of which is used for simulation testing of a train, and each vehicle in the train has one degree of freedom;

[0014] Adhesion-based longitudinal dynamics model: including four wheelset simulation units and a frame body simulation unit. Each wheelset simulation unit includes longitudinal translational freedom and rotational freedom, and the frame body simulation unit has longitudinal translational freedom.

[0015] Three-dimensional semi-physical dynamics model: including wheelset simulation unit, frame simulation unit, and vehicle body simulation unit, each simulation unit includes six degrees of freedom.

[0016] In some embodiments of the present invention, the one-dimensional longitudinal dynamics model, the one-dimensional semi-physical longitudinal dynamics model, the multi-train longitudinal dynamics model, and the adhesion-based longitudinal dynamics model all include:

[0017] Car addition and subtraction calculation unit: used to calculate the status of train addition and subtraction, and confirm whether the train is in online operation or out of service;

[0018] Input interface unit: communicates data with the train control system to obtain data required for simulation calculations of the vehicle addition and subtraction calculation unit and the dynamics calculation unit for use in simulations on the dynamics simulation platform;

[0019] Output interface unit: communicates data with the train control system, status monitoring system, and screen display, and sends the obtained vehicle addition and subtraction calculation results and dynamics calculation results to the corresponding test output system.

[0020] In some embodiments of the present invention, the dynamics calculation unit includes one or a combination of the following subunits:

[0021] Line calculation subunit: obtains the train running mileage, line turnout status, running direction, and determines the line, segment interval and segment interval offset of the train, determines the kilometer mark position of the train line, and calculates the line additional resistance at the train location;

[0022] Hook-and-buffer calculation subunit: obtains the train buffer hysteresis characteristic curve, the relative speed and relative displacement between adjacent vehicles on the line, and calculates the train workshop hook-and-buffer force;

[0023] Basic running resistance calculation subunit: based on vehicle mass, real-time speed and Davis formula, calculates the basic running resistance of the vehicle;

[0024] Starting basic resistance calculation subunit: based on the vehicle mass, calculate the starting resistance of each vehicle;

[0025] Running direction subunit: determines the train running direction according to the train activation terminal signal, activation terminal direction handle signal and line up and down direction information given by the train control system;

[0026] Reset calculation subunit: calculate the control amount according to the change of the train adding and subtracting car status, so as to clear the above-mentioned simulation calculation results of the train stored in the program, or reset the initial value of the integral module of the program simulation calculation;

[0027] The calculation data of each sub-unit is transmitted to the calculation data of each sub-unit for simulation use by the dynamics real-time simulation platform;

[0028] The model also includes a calculation program: a dynamic index signal is calculated based on the running direction signal, the mass matrix, the initial state and the resultant force vector obtained by calculation based on the dynamic calculation unit.

[0029] In some embodiments of the present invention, for a one-dimensional longitudinal dynamics model and a multi-train longitudinal dynamics model, the dynamics calculation unit includes the following subunits further including:

[0030] Traction calculation subunit: based on the traction command, traction percentage and train mass of the train control system, calculates the traction force of each motor vehicle in the train, or, based on the braking command signal, braking percentage signal and electric braking request signal, calculates the electric braking force of each motor vehicle in the train;

[0031] Braking calculation subunit: calculates the air braking force based on the braking command signal, braking percentage signal, train mass, and electric braking force calculated by the traction calculation subunit given by the train control system.

[0032] In some embodiments of the present invention, for the one-dimensional semi-physical longitudinal dynamics model and the adhesion-based longitudinal dynamics model, the input interface unit and the output interface unit further include:

[0033] Communication module with the semi-physical simulation model of the traction system: used to receive the traction torque or electric braking torque of the train and send the running speed of the train;

[0034] Communication module with the semi-physical simulation model of the braking system: used to receive the air braking torque of the train and send the running speed of the train;

[0035] The traction torque and braking torque are derived from a semi-physical simulation model of a train traction system and a braking system.

[0036] In some embodiments of the present invention, based on the longitudinal dynamics model of adhesion, the dynamics calculation unit includes the following subunits further including:

[0037] Primary suspension force calculation subunit: Based on the longitudinal stiffness and damping of the bogie primary system, as well as the relative speed and relative displacement between the wheelset and the frame body, the primary suspension force is calculated and output.

[0038] In some embodiments of the present invention, based on the longitudinal dynamics model of adhesion, the dynamics calculation unit includes the following subunits further including:

[0039] Creep force calculation subunit: Calculates and outputs longitudinal creep force based on the rotational speed and translational speed of each wheelset, axle weight, wheel-rail profile matching, wheel-rail contact surface state, traction or braking conditions, and the increase or decrease in axle weight of each wheelset under the action of hook buffer force.

[0040] In some embodiments of the present invention, the three-dimensional semi-physical dynamics model includes:

[0041] Pre-processing unit: communicates with the traction semi-physical simulation system and the braking semi-physical simulation system, obtains the traction torque / electric braking torque, air braking torque, and performs type conversion on the traction torque data;

[0042] Dynamics model unit: obtains the traction torque / electric braking torque data converted by the pre-processing unit, and obtains the air braking torque for dynamics simulation calculation;

[0043] Post-processing unit: obtains simulation calculation data of the dynamic model unit and calculates train dynamic performance indicators, which include running stability indicators and smoothness indicators.

[0044] In some embodiments of the present invention, the multi-train longitudinal dynamics model includes 96 groups of one-dimensional longitudinal dynamics models.

[0045] The real-time dynamics simulation platform provided by the present invention has the following beneficial effects:

[0046] The present invention provides a dynamic real-time simulation platform as an independent platform, which exchanges data with other train systems through a communication interface to jointly complete simulation tests. In addition, the platform includes a plurality of different dynamic real-time simulation models, each of which simulates the line and train structure as much as possible, meets the requirements of various train simulation tests for dynamic simulation environments, and achieves a universal effect.

[0047] The various types of longitudinal dynamic models provided by the present invention are highly universal, do not distinguish between subways and trains, use matrix and vector calculations, and are adaptive to trains with different numbers of marshalings and different marshaling types, thereby improving the comprehensive test performance of the simulation platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0049] Figure 1 This is the overall architecture diagram of the one-dimensional longitudinal dynamics model of the train.

[0050] Figure 2 This is the calculation flow chart of the calculation program for the one-dimensional longitudinal dynamic model of the train.

[0051] Figure 3 This is the calculation flow chart of the calculation program for the one-dimensional semi-physical longitudinal dynamic model of the train.

[0052] Figure 4 This is the overall architecture diagram of the adhesion-based train longitudinal dynamics model.

[0053] Figure 5 This is the calculation flow chart of the calculation program of the adhesion-based train longitudinal dynamics model.

[0054] Figure 6 This is the calculation flow chart of the calculation program of the adhesion-based train longitudinal dynamics model.

[0055] Figure 7 This is the calculation flow chart of the calculation program of the adhesion-based train longitudinal dynamics model.

[0056] Figure 8 This is the overall architecture diagram of the three-dimensional dynamic model of the train.

[0057] Fig. 9 This is the principle block diagram of the three-dimensional dynamic model of the train;

[0058] Fig.10This is a schematic diagram of the dynamics simulation platform structure. DETAILED DESCRIPTION

[0059] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0060] The invention provides a train dynamics real-time simulation platform which can be used for train testing.

[0061] The simulation platform includes a variety of dynamic simulation models, each of which includes a dynamic calculation unit and an interface unit. The interface unit is used to communicate with the train, including but not limited to the train control system, traction and braking semi-physical simulation system, and auxiliary test units (state monitoring system, screen display, etc.) to obtain simulation test data. The dynamic calculation unit is used to calculate the forces and dynamic indicators borne by each vehicle and output the simulation results.

[0062] refer to Fig.10 Different from the simulation model unit in the prior art, the simulation model unit provided by the present invention includes: a one-dimensional longitudinal dynamics model, a one-dimensional semi-physical longitudinal dynamics model, a multi-train longitudinal dynamics model, an adhesion-based longitudinal dynamics model, and a three-dimensional semi-physical dynamics model. During the test, the appropriate dynamics model can be selected and connected as needed.

[0063] The structure of each simulation model will be described in detail below.

[0064] 1. One-dimensional longitudinal dynamics model

[0065] One-dimensional longitudinal dynamics model: Each vehicle in the train has one degree of freedom.

[0066] The one-dimensional longitudinal dynamics model of the train is built on a model-based visual simulation platform. The overall architecture of the entire model is as follows: Figure 1 As shown in the figure, it is divided into input and output interface program, dynamic calculation program, addition and subtraction program, running direction program, reset program, etc. The calculation process of the dynamic calculation program is as follows Figure 2 shown.

[0067] The longitudinal dynamics model includes:

[0068] Car adding and subtracting calculation unit: used to calculate the car adding and subtracting status of the train, and confirm whether the train is in an online operation state or a stopped operation state; specifically, the car adding and subtracting program determines whether the train is in an online operation state, i.e., adding a car state, or a stopped operation state, i.e., subtracting a car or clearing a car state, according to the vehicle state instantaneous signal given by the train control system, and maintains the state unchanged until the train control system gives a signal to change the vehicle state;

[0069] Dynamics calculation unit: used to calculate the forces and dynamics operation indicators of each vehicle;

[0070] Input interface unit: communicates data with the train control system to obtain the data required for simulation calculation by the vehicle addition and subtraction calculation unit and the dynamics calculation unit, for use by the dynamics simulation platform for simulation;

[0071] Output interface unit: It communicates data with the train control system, status monitoring system and screen display, and sends the obtained vehicle addition and subtraction calculation results and dynamic calculation results to the corresponding test output system so that the real-time simulation test can continue and the test results can be observed.

[0072] Further, the dynamics calculation unit includes:

[0073] Line calculation subunit: obtains the train running mileage, line turnout status, running direction and determines the line, segment interval and segment interval offset of the train, determines the kilometer mark position of the train line, and calculates the line additional resistance at the train location;

[0074] Hook-buffer calculation subunit: obtains the train buffer hysteresis characteristic curve, the relative speed and relative displacement (i.e. the distance between the front and rear vehicles) between adjacent vehicles on the line, and calculates the train workshop hook-buffer force;

[0075] Basic running resistance calculation subunit: based on vehicle mass, real-time speed, and Davis formula F = a + bv + cv 2 , calculate the basic running resistance of the vehicle;

[0076] Starting basic resistance calculation subunit: based on the vehicle mass, calculate the starting resistance of each vehicle;

[0077] Running direction subunit: determines the train running direction according to the train activation end signal and activation end direction handle signal given by the train control system, as well as the up and down direction information of the line;

[0078] Reset calculation subunit: calculate the control amount according to the change of the train adding and subtracting car status, so as to clear the above-mentioned simulation calculation results of the train stored in the program, or reset the initial value of the integral module of the program simulation calculation;

[0079] Traction calculation subunit: based on the traction command of the train control system, the traction percentage, and the train mass, calculates the traction force of each EMU, or, based on the braking command signal, the braking percentage signal, and the electric braking request signal, calculates the electric braking force of each EMU;

[0080] Braking calculation subunit: calculates the air braking force according to the braking command signal, braking percentage signal, train mass, and electric braking force calculated by the traction sub-calculation unit given by the train control system;

[0081] The calculation data of each sub-unit is transmitted to the calculation data of each sub-unit for simulation use by the dynamics real-time simulation platform;

[0082] The model also includes a calculation program unit: the dynamic index is calculated according to the running direction signal, the mass matrix and the resultant force vector calculated by the dynamic calculation unit.

[0083] The model train mass signal used in the above simulation test process is given by the train control system, simulating the change in vehicle weight caused by people getting on and off the train during train operation.

[0084] In addition to the above units, it also includes a reset program. The reset program calculates a control quantity according to the change of the train's adding and subtracting car status, which is used to clear the above train simulation calculation results stored in the program, or reset the initial value of the integral module of the program simulation calculation.

[0085] refer to Figure 2 , the model uses vector and matrix calculations, the train formation is flexible, the mass is variable, the traction and braking systems are implemented in a purely digital simulation form, and fault conditions can be simulated. The line conditions are based on the actual line where the train is running online. The one-dimensional longitudinal dynamics model of the train is jointly simulated with the vehicle control system to realize the real-time running diagram of the train on the line: adding cars, reducing cars, going up, going down, stopping at a fixed point, real-time positioning, etc., and the running performance of the train, the traction and braking capacity of the train, etc. are sent to the vehicle control system, so that the vehicle control system can better control the train and avoid blind control. The interface system is suitable for different vehicle control systems.

[0086] 2. One-dimensional semi-physical longitudinal dynamics model

[0087] One-dimensional semi-physical longitudinal dynamics model: Each vehicle in the train has one degree of freedom.

[0088] The one-dimensional semi-physical longitudinal dynamics model includes: vehicle addition and subtraction calculation unit, dynamics calculation unit, input interface unit, output interface unit, line calculation subunit, hook buffer calculation subunit, basic operation resistance calculation subunit, starting basic resistance calculation subunit, operation direction subunit, and reset program; the functions of the above units are the same as those of the one-dimensional longitudinal dynamics model and will not be repeated here.

[0089] Unlike the one-dimensional longitudinal dynamics model, the semi-physical longitudinal dynamics model also includes:

[0090] Interface with the semi-physical simulation model of the traction system: used to receive the train traction torque required for dynamic simulation calculations, and send the vehicle speed signal required for semi-physical simulation calculations of the traction system;

[0091] Interface with the semi-physical simulation model of the braking system: used to receive the train air braking torque required for dynamic simulation calculations, and send the vehicle speed signal required for semi-physical simulation calculations of the braking system;

[0092] The traction and braking forces used in the one-dimensional semi-physical longitudinal dynamics model simulation test come from the traction system semi-physical simulation model and the braking system semi-physical simulation model.

[0093] The one-dimensional semi-physical longitudinal dynamics model of the train is built on a model-based visual simulation platform. Figure 1 The overall architecture of the one-dimensional longitudinal dynamics model of the train and the calculation process of the dynamics calculation program are as follows: Figure 3 As shown. Among them, the traction and braking forces are calculated by the semi-physical simulation models of the traction system and the braking system respectively, and enter the one-dimensional semi-physical longitudinal dynamics model of the train through the communication module. The remaining subroutines are the same as the one-dimensional longitudinal dynamics model. This model also uses matrix and vector calculations, with flexible train formation and variable quality. The line conditions are based on the actual line where the train is running on the line. The joint simulation of the one-dimensional longitudinal dynamics model of the train and the train control system can realize the real-time running diagram of the train on the line: adding cars, reducing cars, going up, going down, stopping at a fixed point, real-time positioning, etc., and send the train's operating performance, traction and braking capabilities of the train to the train control system, so that the train control system can better control the train and avoid blind control. The interface program is suitable for different train control systems.

[0094] 3. Multi-train longitudinal dynamics model

[0095] Multi-train longitudinal dynamics model: includes multiple one-dimensional longitudinal dynamics models, each of which is used for simulation testing of a train, and each car in the train has one degree of freedom.

[0096] The multi-train longitudinal dynamics model is an expansion of multiple train one-dimensional longitudinal dynamics models. In some embodiments of the present invention, the multi-train longitudinal dynamics model includes 96 groups of one-dimensional longitudinal dynamics models.

[0097] Each one-dimensional longitudinal dynamics model parameter is independent of each other and can be based on the same real train running line or on different train running lines. Using a multi-train longitudinal dynamics model, multiple train simulation tests can be performed simultaneously.

[0098] The trains on the same running line can be produced by the same manufacturer with the same train parameters, or they can be produced by different manufacturers with different train parameters. Each train has an ID number, which is convenient for the train control system to control whether each train is on the line, that is, to add and reduce cars, and clear cars. Each train has the characteristics and functions described in the aforementioned one-dimensional longitudinal dynamics model of the train (the model also uses matrix and vector calculations, and the train formation is flexible and the quality is variable. The line conditions are based on the actual line where the train is running on the line. The one-dimensional longitudinal dynamics model of the train is jointly simulated with the train control system to realize the real-time running diagram of the train on the line: adding cars, reducing cars, going up, going down, stopping at a fixed point, real-time positioning, etc., and the running performance of the train, the traction and braking capacity of the train, etc. are sent to the train control system, so that the train control system can better control the train and avoid blind control). When the train control system adds a car, it can initially locate the train to any position on the line. Using the multi-train longitudinal dynamics model, in conjunction with other systems, the train operation diagram of the line can be planned, and the energy consumption of the line can also be calculated.

[0099] 4. Longitudinal dynamics model based on adhesion

[0100] Adhesion-based longitudinal dynamics model: includes four wheelset simulation units and a frame body simulation unit. Each wheelset simulation unit includes longitudinal translational freedom and rotational freedom, and the frame body simulation unit has longitudinal translational freedom.

[0101] The adhesion-based train longitudinal dynamics model is built on a model-based visual simulation platform. Each vehicle has 9 degrees of freedom, including the longitudinal translation of the frame body, the longitudinal translation of the wheelset (four groups) and the rotation. The overall architecture of the program is as follows Figure 4 As shown. You can also Figure 1 As shown in the figure, the addition and subtraction program, reset program, and running direction program are added to expand the model into a running model with adhesion creep calculation. The calculation process of the dynamic calculation program is as follows Figures 5 to 7 shown.

[0102] The adhesion-based longitudinal dynamics model includes: a vehicle addition and subtraction calculation unit, an input interface unit, an output interface unit, a line calculation subunit, a hook and buffer calculation subunit, a basic operating resistance calculation subunit, a starting basic resistance calculation subunit, and an operating direction subunit; the functions of the above units are the same as those of the one-dimensional longitudinal dynamics model, and will not be repeated here.

[0103] The difference is that the input interface unit and the output interface unit further include:

[0104] Communication module with the semi-physical simulation model of the traction system: used to receive the traction torque or electric braking torque of the train and send the running speed of the train;

[0105] Communication module with the semi-physical simulation model of the braking system: used to receive the air braking torque of the train and send the running speed of the train;

[0106] Semi-physical simulation model of train traction system and braking system from traction torque and braking torque.

[0107] In addition to the above single function, in some embodiments of the present invention, based on the longitudinal dynamics model of adhesion, the dynamics calculation unit further calculates the dynamics indexes of wheelset translation, wheelset rotation and frame body translation, and further includes the following subunits:

[0108] Primary suspension force calculation subunit: Based on the longitudinal stiffness and damping of the bogie primary system, as well as the relative speed and relative displacement between the wheelset and the frame body, the primary suspension force between the wheelset and the frame body is calculated according to the formula F=kΔx+dΔv.

[0109] Creep force calculation subunit: wheel-rail profile matching database and wheel-rail contact surface state database are established. Set the fixed or variable contact surface state required during the simulation test, calculate and output the longitudinal creep force based on the rotation speed and translation speed of each wheelset, axle weight, wheel-rail profile matching, wheel-rail contact surface state, traction or braking conditions, and the axle weight increase or decrease of each wheelset under the action of hook buffer force;

[0110] The traction torque and braking torque used in the above calculation process come from the semi-physical simulation model of the train traction system and braking system, and receive data through the input interface program.

[0111] The adhesion-based longitudinal dynamic model uses matrix and vector calculations, does not distinguish between subways and EMUs, and is adaptive to trains of different numbers and types of marshaling, with strong versatility. The traction torque and braking torque are the calculation results of the semi-physical model of the traction system and the braking system, which are input through communication. The additional resistance of the line can be a straight track, a ramp, or a real vehicle running line according to the test needs. The POLACH algorithm is used to calculate the longitudinal creep force between the wheel and the rail. In the calculation, it can be defined that the contact state between the wheel and the rail of any wheelset of any vehicle in a certain section of the line changes. The structure and layout of traction and braking on the bogie are taken into account, the increase and decrease of load caused by the traction and braking process is taken into account, and the increase and decrease of load caused by the hook-and-buffer force between vehicles is also taken into account.

[0112] The adhesion-based train longitudinal dynamics model, together with the train control system, traction system and braking system, can start at zero speed, conduct anti-skid and anti-spin tests, and verify the train control logic of the traction system and braking system.

[0113] In addition, the train longitudinal dynamics model with adhesion sets a wheel-rail profile matching type library, from which you can select the wheel-rail profile matching type; the model also sets a wheel-rail contact surface state library, from which you can select any wheel-rail contact surface state, or you can customize the wheel-rail surface contact state. You can also gradually increase the wheel-rail contact surface state types in the library to expand the model.

[0114] 5. Three-dimensional semi-physical dynamics model

[0115] Three-dimensional semi-physical dynamics model: including wheelset simulation unit, frame simulation unit, and vehicle body simulation unit, each simulation unit includes six degrees of freedom.

[0116] The three-dimensional semi-physical model of train dynamics is a dynamic model that is built using multi-body dynamics simulation software and undergoes real-time simulation tests on a real-time simulator.

[0117] The overall structure of the train 3D dynamics semi-physical model is as follows: Figure 8 As shown in FIG. 1 , it includes a pre-processing unit, a dynamic model unit and a post-processing unit. The pre- and post-processing programs are constructed by a model-based visual simulation platform module.

[0118] Pre-processing unit: communicates with the train traction semi-physical simulation system to obtain traction torque data and perform type conversion; specifically, the pre-processing program mainly converts the data type of the traction torque input into the dynamics model of the traction system to match the type requirements of the dynamics model for the input quantity. Communicates with the train braking semi-physical simulation system to obtain the air braking torque.

[0119] Dynamics model unit: obtains pre-processed traction torque data and air brake torque data, and performs dynamics simulation calculations;

[0120] Post-processing unit: obtains the simulation calculation data of the dynamic model unit and calculates the train dynamic performance indicators, which include running stability indicators and stability indicators. Specifically, the post-processing program calculates the performance parameters output by the dynamic model according to the performance indicators required by the GB / T5599-2019 standard, such as axle lateral force, derailment coefficient, wheel weight reduction rate, etc., and calculates the stability index and comfort index according to the algorithm given in the standard.

[0121] The three-dimensional dynamic modeling takes into account the wheel-rail profile, wheel-rail surface contact state, inertia parameters of each component, and primary and secondary suspension parameters. The train modeling also takes into account the force of the workshop coupling system. Curves and ramps are set in the model according to the train running route, and track unevenness is set. The principle block diagram of the three-dimensional dynamic semi-physical model of the train is shown in the figure. Fig. 9As shown in the figure, the measurement points of dynamic performance parameters are set according to the standard GB / T5599-2019. The model calculates and outputs performance parameters such as wheel-rail vertical force, speed, frame and vehicle body acceleration.

[0122] The dynamic real-time simulation platform provided by the present invention constructs different dynamic models, simulates the train running on the line, and cooperates with the traction system, braking system, train control system and other systems to complete a series of train tests in a train running environment that is as realistic as possible. The use of dynamic real-time simulation testing not only saves manpower and material costs and reduces test time, but also allows the platform to conduct fault tests that are not easy to meet test conditions on the actual train running line, becoming a practical and effective supplement to the actual train line test for evaluating train performance.

[0123] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A real-time train dynamics simulation platform, characterized in that: It includes multiple simulation models, each simulation model includes a dynamics calculation unit and an interface unit, the interface unit is used to communicate with the train control system to be tested, and the dynamics calculation unit is used to calculate the force and dynamics performance index borne by each vehicle; the simulation model includes: One-dimensional longitudinal dynamics model: Each vehicle in the train has one degree of freedom; One-dimensional semi-physical longitudinal dynamics model: Each vehicle in the train has one degree of freedom; Multi-train longitudinal dynamics model: includes multiple one-dimensional longitudinal dynamics models, each of which is used for simulation testing of a train, and each vehicle in the train has one degree of freedom; Adhesion-based longitudinal dynamics model: including four wheelset simulation units and a frame body simulation unit. Each wheelset simulation unit includes longitudinal translational freedom and rotational freedom, and the frame body simulation unit has longitudinal translational freedom. Three-dimensional semi-physical dynamics model: including wheelset simulation unit, frame simulation unit, and vehicle body simulation unit, each simulation unit includes six degrees of freedom; The one-dimensional longitudinal dynamics model, the one-dimensional semi-physical longitudinal dynamics model, the multi-train longitudinal dynamics model, and the adhesion-based longitudinal dynamics model all include: Car addition and subtraction calculation unit: used to calculate the status of train addition and subtraction, and confirm whether the train is in online operation or out of service; Input interface unit: communicates data with the train control system to obtain the data required for simulation calculation of the vehicle addition and subtraction calculation unit and the dynamics calculation unit for use in simulation on the dynamics simulation platform; Output interface unit: communicates data with the train control system, the state monitoring system, and the screen display to send the obtained vehicle addition and subtraction calculation results and dynamics calculation results to the corresponding test output system; The dynamics calculation unit includes one or a combination of the following subunits: Line calculation subunit: obtains the train running mileage, line turnout status, running direction, and determines the line, segment interval and segment interval offset of the train, determines the kilometer mark position of the train line, and calculates the line additional resistance at the train location; Hook-and-buffer calculation subunit: obtains the train buffer hysteresis characteristic curve, the relative speed and relative displacement between adjacent vehicles on the line, and calculates the train workshop hook-and-buffer force; Basic running resistance calculation subunit: based on vehicle mass, real-time speed and Davis formula, calculates the basic running resistance of the vehicle; Starting basic resistance calculation subunit: based on the vehicle mass, calculate the starting resistance of each vehicle; Running direction subunit: determines the train running direction according to the train activation terminal signal, activation terminal direction handle signal and line up and down direction information given by the train control system; Reset calculation subunit: calculate the control amount according to the change of the train adding and subtracting car status, so as to clear the above-mentioned simulation calculation results of the train stored in the program, or reset the initial value of the integral module of the program simulation calculation; The calculation data of each subunit is used for simulation on the dynamics real-time simulation platform; The model also includes a calculation program: a dynamic index signal is calculated based on the running direction signal, the mass matrix, the initial state and the resultant force vector obtained by calculation based on the dynamic calculation unit.

2. The train dynamics real-time simulation platform according to claim 1, characterized in that: For the one-dimensional longitudinal dynamics model and the multi-train longitudinal dynamics model, the dynamics calculation unit includes the following sub-units further including: Traction calculation subunit: based on the traction command, traction percentage and train mass of the train control system, calculates the traction force of each motor vehicle in the train, or, based on the braking command signal, braking percentage signal and electric braking request signal, calculates the electric braking force of each motor vehicle in the train; Braking calculation subunit: calculates the air braking force based on the braking command signal, braking percentage signal, train mass, and electric braking force calculated by the traction calculation subunit given by the train control system.

3. The train dynamics real-time simulation platform according to claim 1, characterized in that: For the one-dimensional semi-physical longitudinal dynamics model and the adhesion-based longitudinal dynamics model, the input interface unit and the output interface unit further include: Communication module with the semi-physical simulation model of the traction system: used to receive the traction torque or electric braking torque of the train and send the running speed of the train; Communication module with the semi-physical simulation model of the braking system: used to receive the air braking torque of the train and send the running speed of the train; The traction torque and braking torque are derived from a semi-physical simulation model of a train traction system and a braking system.

4. The train dynamics real-time simulation platform according to claim 1, characterized in that: Based on the longitudinal dynamics model of adhesion, the dynamics calculation unit includes the following subunits further including: Primary suspension force calculation subunit: Based on the longitudinal stiffness and damping of the bogie primary system, as well as the relative speed and relative displacement between the wheelset and the frame body, the primary suspension force is calculated and output.

5. The train dynamics real-time simulation platform according to claim 1, characterized in that: Based on the longitudinal dynamics model of adhesion, the dynamics calculation unit includes the following subunits further including: Creep force calculation subunit: Calculates and outputs longitudinal creep force based on the rotational speed and translational speed of each wheelset, axle weight, wheel-rail profile matching, wheel-rail contact surface state, traction or braking conditions, and the increase or decrease in axle weight of each wheelset under the action of hook buffer force.

6. The train dynamics real-time simulation platform according to claim 1, characterized in that: The three-dimensional semi-physical dynamics model includes: Pre-processing unit: communicates with the traction semi-physical simulation system and the braking semi-physical simulation system, obtains the traction torque / electric braking torque, air braking torque, and performs type conversion on the traction torque data; Dynamics model unit: obtains the traction torque / electric braking torque data converted by the pre-processing unit, and obtains the air braking torque for dynamics simulation calculation; Post-processing unit: obtains simulation calculation data of the dynamic model unit and calculates train dynamic performance indicators, which include running stability indicators and smoothness indicators.

7. The train dynamics real-time simulation platform according to claim 1, characterized in that: The multi-train longitudinal dynamics model includes 96 groups of one-dimensional longitudinal dynamics models.

Images