Real-time Measurement System, Method and Equipment for Rail-wheel Adhesion State of Rail Transit

Abstract

This application belongs to the technical field of rail transit, and provides a real-time measurement system, method, storage medium and device for the wheel-rail adhesion state of rail transit. The system includes: a wheel-rail adhesion state measurement device and an on-vehicle control system; the wheel-rail adhesion state measurement device is installed on the train and connected to the on-vehicle control system; the wheel-rail adhesion state measurement device performs wheel-rail adhesion state measurement based on limit tests or wheel-rail adhesion state measurement based on target actions according to the real-time operating conditions of the train and the intended operating conditions of the train obtained from the on-vehicle control system. The real-time measurement system for the wheel-rail adhesion state of rail transit in this application improves the measurement accuracy of the wheel-rail adhesion state of rail transit.

Description

Technical Field

[0001] This application belongs to the technical field of rail transit, and in particular relates to a real-time measurement system, method, storage medium and device for the wheel-rail adhesion state of rail transit. Background Art

[0002] The operation of rail transit trains depends on the reliable control of traction (acceleration) and braking (deceleration). The realization of traction and braking mainly transmits the tangential (along the train running direction) creep force through the interaction of wheel-rail contact. The characteristics of this interaction are called adhesion characteristics. The adhesion characteristics determine the effect of transmitting the circumferential force (from the rotation of the drive shaft or the friction of the brake) to the tangential force under relatively stable contact conditions between the wheel and the rail, which is a special rolling friction problem. The adhesion characteristics are not only related to factors such as contact patch pressure, wheel-rail surface materials, wheel-rail relative motion state, roughness of the contact surface, and environmental state, but also affected by wheel-rail creep, wheel rolling speed, and vibration of the drive system.

[0003] During the high-speed operation of the train, the influence of the wheel-rail adhesion state on the train operation state is particularly significant. Due to changes in factors such as rail surface conditions and weather conditions, the wheel-rail adhesion state may change suddenly, resulting in the traction or braking force of the train breaking through the adhesion limit. Especially under the braking conditions of the train, such sudden changes are likely to cause wheel locking, significantly increasing the braking distance of the train and having an adverse impact on operation safety. At present, based on a large number of laboratory tests and field tests, empirical formulas for the wheel-rail adhesion coefficient of main types of locomotives have been basically formed, and the mathematical relationship between the adhesion coefficient and the rail surface state and train speed has been established. However, the existing technology has not solved the problem of the real-time complex changes in the rail surface state, and the real-time quantitative detection technology for the wheel-rail adhesion state still needs to be further studied.

[0004] Traditional rail transit adhesion coefficient measurement or calculation methods are generated based on a large amount of actual test data, mainly establishing the relationship between the wheel-rail adhesion coefficient corresponding to different train speeds under typical rail surface conditions (mainly dry and wet). However, it is impossible to consider other types of rail surface conditions or sudden changes in the rail surface state, and it is mainly used for centralized power trains and has not been applied to decentralized power trains.

[0005] Some technologies perform real-time measurement of the wheel-rail adhesion state by adding on-vehicle equipment, and mainly use the classification or grading of the rail surface state as the main processing means. For example, the rail surface state is monitored by video surveillance. However, this method is difficult to perform quantitative analysis of the wheel-rail adhesion state, lacks the accuracy to support train operation control decisions, and requires high computing power for real-time monitoring.

[0006] Based on the variation relationship between the train speed and the driving wheel speed, some technologies establish a calculation model that includes the wheel speed variation and the first-order difference variation of the wheel speed, and generate the adhesion relationship between the wheel and the rail through the relationship between the wheel speed variation characteristics and the pre-calibrated threshold. Such methods require the assumption that the measurement of the wheel speed and the vehicle speed is accurate and synchronous, and can only be effectively measured under the condition of train braking, and cannot be measured under other train operating conditions. Summary of the Invention

[0007] In view of the deficiencies of the existing technologies, the present application provides a real-time measurement system, method, storage medium and device for the adhesion state of rail transit wheels and rails. By using the wheel-rail adhesion state measurement device and the on-vehicle control system, based on the real-time operating conditions of the train and the operating conditions of the train intention execution, perform the measurement of the wheel-rail adhesion state based on the limit test or the measurement of the wheel-rail adhesion state based on the target action. Through the contact method, the wheel-rail adhesion state can be directly measured quantitatively, improving the measurement accuracy of the wheel-rail adhesion state of rail transit.

[0008] The present application is realized through the following technical solutions:

[0009] A wheel-rail adhesion state measurement device and an on-vehicle control system;

[0010] The wheel-rail adhesion state measurement device is installed on the train and is connected to the on-vehicle control system;

[0011] The wheel-rail adhesion state measurement device performs the measurement of the wheel-rail adhesion state based on the limit test or the measurement of the wheel-rail adhesion state based on the target action according to the real-time operating conditions of the train and the operating conditions of the train intention execution obtained from the on-vehicle control system.

[0012] Optionally,

[0013] The measurement of the wheel-rail adhesion state based on the limit test includes: the measurement based on the limit acceleration test and the measurement based on the limit braking test; and / or,

[0014] The measurement of the wheel-rail adhesion state based on the target action includes: the measurement based on the target acceleration action and the measurement based on the target braking action.

[0015] Optionally,

[0016] If the real-time operating condition of the train is the traction condition or the non-traction and non-braking condition, then perform the measurement based on the limit acceleration test;

[0017] If the real-time operating condition of the train is the braking condition, then perform the measurement based on the limit braking test.

[0018] Optionally,

[0019] If the train intends to execute the traction condition, then perform the measurement based on the target acceleration action;

[0020] If the train intends to execute a braking condition, perform a measurement based on the target braking action.

[0021] Optionally,

[0022] By performing a measurement of the wheel-rail adhesion state based on an extreme test, calculate and obtain the real-time wheel-rail adhesion coefficient or the wheel-rail safety adhesion coefficient, and output a triple data including the real-time wheel-rail adhesion coefficient or the wheel-rail safety adhesion coefficient to the on-vehicle control system; and / or,

[0023] By performing a measurement of the wheel-rail adhesion state based on the target action, judge the feasibility of the condition that the train intends to execute, and output a judgment result to the on-vehicle control system.

[0024] Optionally,

[0025] The physical structure of the wheel-rail adhesion state measuring device includes: a fixed component, a pressure control component, a connection component, a test wheel, an acceleration control component, a braking control component, and a speed measuring component.

[0026] Optionally,

[0027] The control structure of the wheel-rail adhesion state measuring device includes: a control center, a speed detector, a pressure detector, a braking controller, an acceleration controller, a pressure controller, and a position controller; wherein, the control center is connected to the on-vehicle control system, the speed detector is connected to the speed measuring component, the pressure detector, the pressure controller, and the position controller are connected to the pressure control component, the braking controller is connected to the braking control component, and the acceleration controller is connected to the acceleration controller.

[0028] This application also provides a method for real-time measurement of the wheel-rail adhesion state of rail transit, and the method includes:

[0029] Obtain the real-time operating condition of the train and the condition that the train intends to execute from the on-vehicle control system;

[0030] Use the wheel-rail adhesion state measuring device to perform a measurement of the wheel-rail adhesion state based on an extreme test or a measurement of the wheel-rail adhesion state based on the target action according to the real-time operating condition of the train and the condition that the train intends to execute.

[0031] Optionally,

[0032] The measurement of the wheel-rail adhesion state based on the extreme test includes: measurement based on an extreme acceleration test and measurement based on an extreme braking test; and / or,

[0033] The measurement of the wheel-rail adhesion state based on the target action includes: measurement based on a target acceleration action and measurement based on a target braking action.

[0034] Optionally,

[0035] If the real-time operating condition of the train is a traction condition or a non-traction and non-braking condition, perform the measurement based on the ultimate acceleration test;

[0036] If the real-time operating condition of the train is a braking condition, perform the measurement based on the ultimate braking test.

[0037] Optionally,

[0038] If the train intends to execute a traction condition, perform the measurement based on the target acceleration action;

[0039] If the train intends to execute a braking condition, perform the measurement based on the target braking action.

[0040] Optionally,

[0041] By performing the wheel-rail adhesion state measurement based on the ultimate test, calculate and obtain the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient, and output the triple data including the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient to the on-vehicle control system; and / or,

[0042] By performing the wheel-rail adhesion state measurement based on the target action, judge the feasibility of the condition that the train intends to execute, and output the judgment result to the on-vehicle control system.

[0043] This application also provides a computer-readable storage medium storing one or more programs, which when executed, can implement the foregoing real-time measurement method for the rail transit wheel-rail adhesion state.

[0044] This application also provides a device, including a processor, a communication interface, a computer-readable storage medium, and a communication bus; wherein, the processor, the communication interface, and the computer-readable storage medium communicate with each other through the communication bus;

[0045] The processor is used to execute the programs stored in the computer-readable storage medium.

[0046] Compared with the prior art, this application has the following advantages:

[0047] 1. The real-time measurement system for the rail transit wheel-rail adhesion state proposed in this application uses the wheel-rail adhesion state measurement device and the on-vehicle control system, and performs the wheel-rail adhesion state measurement based on the ultimate test or the wheel-rail adhesion state measurement based on the target action according to the real-time operating condition of the train and the condition that the train intends to execute. It can quantitatively measure the rail transit wheel-rail adhesion state at any position at any moment during the train operation process, and has the characteristics of short measurement time (cycle) and high measurement density, improving the measurement accuracy of the rail transit wheel-rail adhesion state.

[0048] 2. According to the real-time operating conditions and intentions of the train, the operating conditions can be executed, and the wheel-rail adhesion state measurement based on the limit test or the wheel-rail adhesion state measurement based on the target action can be respectively performed. The wheel-rail adhesion state measurement based on the limit test can measure the wheel-rail adhesion state at any position and can achieve high-density continuous measurement of the wheel-rail adhesion state on the line; the wheel-rail adhesion state measurement based on the target action can pre-test the traction or braking force of the train through the real-time measurement device of the rail transit wheel-rail adhesion state to analyze whether the target traction or braking force will cause adverse situations exceeding the limit adhesion force, and feedback the results to the on-vehicle operation control system to improve the safety of rail transit operation.

[0049] 3. Through the wheel-rail adhesion state measurement device, it can be synchronized with the actual dynamic process during the train operation, and the occurrence of the critical state of the sudden change of the test wheel speed and the accurate capture of the real-time vertical pressure under the critical state can be realized. This vertical pressure can reflect the real-time wheel-rail contact state, fully considering complex influencing conditions such as the curve and slope of the track and the change of the longitudinal force of the train, so as to obtain accurate wheel-rail adhesion state measurement results.

[0050] 4. Through the information interaction between the wheel-rail adhesion state measurement device and the on-vehicle control system of the rail transit train, the operating conditions to be executed by the train can be tested and verified through this device, improving the safety of train operation.

[0051] 5. The wheel-rail adhesion state measurement device has a complete physical structure and control results, and can achieve high-precision measurement of the rail transit wheel-rail adhesion state under low computing power requirements. The control logic is simple and can be closed-loop, and only continuous monitoring records, differential comparison, and elementary mathematical calculations are required to achieve the result output.

[0052] Other features and advantages of the present application will be described in the subsequent description, and part of them will become obvious from the description or be understood by implementing the present application. The objectives and other advantages of the present application can be realized and obtained through the structures pointed out in the description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0054] Figure 1 Shows the structural schematic diagram of the real-time measurement system of the rail transit wheel-rail adhesion state;

[0055] Figure 2Shows a schematic physical structure diagram of the wheel-rail adhesion state measurement device according to an embodiment of the present application;

[0056] Figure 3 Shows a schematic control structure diagram of the wheel-rail adhesion state measurement device according to an embodiment of the present application;

[0057] Figure 4 Shows a schematic measurement principle diagram based on the extreme acceleration test according to an embodiment of the present application;

[0058] Figure 5 Shows a schematic diagram of the change in wheel-rail adhesion state based on the extreme acceleration test according to an embodiment of the present application;

[0059] Figure 6 Shows a schematic measurement principle diagram based on the extreme braking test according to an embodiment of the present application;

[0060] Figure 7 Shows a schematic measurement principle diagram based on the target acceleration action according to an embodiment of the present application;

[0061] Figure 8 Shows a schematic measurement principle diagram based on the target braking action according to an embodiment of the present application;

[0062] Figure 9 Shows a schematic flow block diagram of the real-time measurement method for the wheel-rail adhesion state of rail transit;

[0063] Figure 10 Is a schematic structural diagram of a device according to an embodiment of the present application. Detailed implementation manners

[0064] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0065] Refer to the attached Figure 1 , The system of the present application includes:

[0066] A wheel-rail adhesion state measurement device and a vehicle-mounted control system;

[0067] The wheel-rail adhesion state measurement device is installed on the train bogie or car body and is connected to the vehicle-mounted control system;

[0068] Among them, the physical structure of the wheel-rail adhesion state measurement device includes: a fixed component, a pressure control component, a connection component, a test wheel, an acceleration control component, a braking control component, and a speed measurement component,

[0069] Among them, the control structure of the wheel-rail adhesion state measuring device includes: a control center, a speed detector, a pressure detector, a brake controller, an acceleration controller, a pressure controller, and a position controller; among them, the control center is connected to the vehicle-mounted control system, the speed detector is connected to the speed measuring component, the pressure detector, the pressure controller, and the position controller are connected to the pressure control component, the brake controller is connected to the brake control component, and the acceleration controller is connected to the acceleration control component;

[0070] The wheel-rail adhesion state measuring device performs wheel-rail adhesion state measurement based on an extreme test or wheel-rail adhesion state measurement based on a target action according to the real-time operating conditions of the train and the intended operating conditions of the train obtained from the vehicle-mounted control system.

[0071] Among them, the wheel-rail adhesion state measurement based on the extreme test includes: measurement based on an extreme acceleration test and measurement based on an extreme braking test; and / or,

[0072] The wheel-rail adhesion state measurement based on the target action includes: measurement based on a target acceleration action and measurement based on a target braking action,

[0073] Among them, if the real-time operating condition of the train is a traction condition or a non-traction and non-braking condition, then the measurement based on the extreme acceleration test is performed;

[0074] If the real-time operating condition of the train is a braking condition, then the measurement based on the extreme braking test is performed,

[0075] Among them, if the train intends to execute a traction condition, then the measurement based on the target acceleration action is performed;

[0076] If the train intends to execute a braking condition, then the measurement based on the target braking action is performed,

[0077] Among them, by performing the wheel-rail adhesion state measurement based on the extreme test, the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient is calculated and a triple data including the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient is output to the vehicle-mounted control system; and / or,

[0078] By performing the wheel-rail adhesion state measurement based on the target action, the feasibility of the intended operating condition of the train is judged and the judgment result is output to the vehicle-mounted control system.

[0079] Specifically,

[0080] This application proposes a wheel-rail adhesion state measurement system that uses a wheel-rail adhesion state measuring device to measure the wheel-rail adhesion state of rail transit in real time.

[0081] I. Physical and control structures of the wheel-rail adhesion state measuring device.

[0082] The wheel-rail adhesion state measuring device is installed on the fixed structure of the bogie or car body of a rail transit train. Its physical structure includes: a fixing component, a pressure control component, a connecting component, a test wheel, an acceleration control component, a braking control component, and a speed measuring component.

[0083] The control structure of the wheel-rail adhesion state measuring device includes: a control center, a speed detector, a pressure detector, a braking controller, an acceleration controller, a pressure controller, and a position controller. Among them, the control center is connected to the on-vehicle control system, the speed detector is connected to the speed measuring component, the pressure detector, the pressure controller, and the position controller are connected to the pressure control component, the braking controller is connected to the braking control component, and the acceleration controller is connected to the acceleration control component.

[0084] 1. Physical structure.

[0085] See the appendix Figure 2 , the physical structure of the wheel-rail adhesion state measuring device includes:

[0086] (A1) Fixing component: used to stably connect the device to the fixed structure of the running gear. The preferred connection method is riveting. It is connected to the pressure control component, and the connection method is detachable.

[0087] (A2) Pressure control component: used to connect the fixing component and the connecting component, with a retracting function, a pressurizing function, and a pressure detection function. The retracting function can lift the connecting component, so that the test wheel is not in contact with the track; the pressurizing function refers to generating a vertical pressure of a target size to increase the vertical pressure between the test wheel and the track. The maximum vertical force that can be applied is; the pressure detection function is to detect the pressure between the fixing component and the connecting component.

[0088] (A3) Connecting component: used to rigidly connect the pressure control component, the test wheel, the acceleration control component, the braking control component, and the speed measuring component.

[0089] (A4) Test wheel: includes a wheel body and a wheel axle. The wheel axle is fixed to the connecting component, and the wheel body can rotate around the wheel axle. The shape of the wheel body is the same as that of the wheel set on the bogie, that is, it includes a tread and a flange. The materials of the tread and the flange are the same as those of the wheel set tread on the bogie. The material of the wheel body can be the same as that of the tread and the flange, or a lightweight polymer material can be used to reduce the mass of the device. When the pressure control component does not execute the retracting function, the test wheel is in a state of only contact with the track but without vertical pressure.

[0090] (A5) Acceleration control component, connected to the connecting component, with an acceleration function, applying an acceleration force to the test wheel by electromagnetic or physical friction means. The preferred one is a brushless motor, and the maximum acceleration force that can be applied is.

[0091] (A6) The braking control component, connected to the connection component, has a braking function and applies a braking force to the test wheel by physical friction or electromagnetic means. Preferably, it is friction braking, and the maximum braking force that can be applied is

[0092] (A7) The speed measurement component, connected to the connection component, has a speed detection function and can detect and output the real-time rotation speed of the test wheel.

[0093] In this embodiment, the height of the wheel-rail adhesion state measuring device shall not be less than the distance from the fixed surface of the running gear to the top of the rail when the pressure control component does not perform the retraction function.

[0094] The size of the test wheel in the wheel-rail adhesion state measuring device shall not exceed the size of the wheel set. Preferably, the diameter size does not exceed 20 cm.

[0095] The measurement ability of the rail transit wheel-rail adhesion state measuring device depends on the maximum vertical force that the pressure control component can apply , the maximum acceleration force that the acceleration control component can apply , the maximum braking force that the braking control component can apply , and shall satisfy formulas (1) to (3).

[0096]

[0097] In the formula, is the maximum vertical force that can be applied; is the mass of the rail transit wheel-rail adhesion state measuring device; is the acceleration due to gravity, with a value of 9.81 ; is the expansion coefficient of the equipment mass, with a preferred value of 10, and other values can also be taken.

[0098]

[0099] In the formula, is the maximum acceleration force that can be applied; is the maximum vertical force that can be applied; is the traction force distributed to a single wheel of each powered axle when the train runs at the maximum traction force; is the vertical pressure borne by a single wheel when the train runs in the unloaded state.

[0100]

[0101] In the formula, is the maximum braking force that can be applied; is the maximum acceleration force that can be applied.

[0102] 2. Control structure.

[0103] See AppendixFigure 3 , the control structure of the wheel-rail adhesion state measuring device includes:

[0104] (B1) Control center: Connects all detectors (S2)-(S3) and all controllers (S4)-(S7), reads the states output by the detectors, and issues control instructions to the controllers. Generates the real-time state of wheel-rail adhesion through calculation. Connects to the on-vehicle control system, reads the train's actual speed measurement information, and transmits the real-time state of wheel-rail adhesion to the on-vehicle control system.

[0105] (B2) Speed detector: Connects to or is built into the speed measurement component, connects to the control center, and measures and transmits the rotation speed of the test wheel to the control center in real time. Preferably, the measurement frequency of the rotation speed is not less than 2 Hz.

[0106] (B3) Pressure detector: Connects to or is built into the pressure control component, connects to the control center, and measures and transmits the vertical pressure generated by the pressure control component to the control center in real time.

[0107] (B4) Brake controller: Connects to or is built into the brake control component, connects to the control center, and controls the brake control component to apply the target braking force to the test wheel according to the control center's instructions. If the braking force in the instruction is greater than the maximum braking force that the pressure control component can apply , then apply the maximum braking force .

[0108] (B5) Acceleration controller: Connects to or is built into the acceleration control component, connects to the control center. Controls the acceleration control component to apply the target acceleration force to the test wheel according to the control center's instructions. If the acceleration force in the instruction is greater than the maximum acceleration force that the pressure control component can apply , then apply the maximum acceleration force .

[0109] (B6) Pressure controller: Connects to or is built into the pressure control component, connects to the control center. Controls the pressure control component to generate the target vertical pressure according to the control center's instructions. If the vertical pressure in the instruction is greater than the maximum pressure that the pressure control component can apply , then apply the maximum pressure .

[0110] (B7) Position controller: Connects to or is built into the pressure control component, connects to the control center. Controls the pressure control component to perform the retraction and non-retraction functions according to the control center's instructions.

[0111] In the above control structure, the various parts can be connected by wired or wireless means, and the wired method is the preferred method.

[0112] Second, the wheel-rail adhesion state measuring device executes wheel-rail adhesion state measurement based on limit tests or wheel-rail adhesion state measurement based on target actions according to the real-time operating conditions of the train and the intended operating conditions of the train obtained from the on-vehicle control system.

[0113] The wheel-rail adhesion state measurement based on limit tests includes: measurement based on limit acceleration tests and measurement based on limit braking tests; and / or,

[0114] The wheel-rail adhesion state measurement based on target actions includes: measurement based on target acceleration actions and measurement based on target braking actions.

[0115] If the real-time operating conditions of the train are traction conditions or non-traction and non-braking conditions, then an acceleration measurement mode is executed;

[0116] If the real-time operating conditions of the train are braking conditions, then a braking measurement mode is executed.

[0117] If the train intends to execute a traction condition, then measurement based on target acceleration actions is executed;

[0118] If the train intends to execute a braking condition, then measurement based on target braking actions is executed.

[0119] The rail transit wheel-rail adhesion state measurement system can be used to implement two measurement schemes to cope with different measurement objectives, namely, wheel-rail adhesion state measurement based on limit tests and wheel-rail adhesion state measurement based on target actions. Among them, the wheel-rail adhesion state measurement based on limit tests can be used to measure the wheel-rail adhesion state at any position to achieve high-density continuous measurement of the line wheel-rail adhesion state; the wheel-rail adhesion state measurement based on target actions can be used to pre-test the traction or braking force of the train through the wheel-rail adhesion state real-time measuring device to analyze whether the target traction force or braking force will cause adverse situations exceeding the limit adhesion force.

[0120] The wheel-rail adhesion state measuring device is fixed on the train bogie or car body. During the train operation, the wheel-rail adhesion state measuring device should have the same horizontal speed and test wheel rotation speed as the train. To avoid additional wheel-rail adhesion state measurement deviations caused by the difference between the test wheel speed and the vehicle speed corresponding wheel speed, in the embodiments of the two measurement schemes, the test wheel rotation speed corresponding to the real-time train speed is used as the base speed. Since the measurement period is short and the real-time train speed changes little within the measurement period, the real-time train speed at the start of the test is used as the train speed for this test period.

[0121] The preparations before rail transit wheel-rail adhesion state measurement include:

[0122] Judge whether the rail-wheel adhesion state measuring device of the rail transit is in the retracted state. If it is in the retracted state, control the pressure control device to be in the non-retracted state through the position controller;

[0123] Convey instructions through the pressure controller to control the pressure control device to apply a vertical force;

[0124] Obtain the real-time speed, position of the train and the rotation speed of the test wheel, so that the relative error between the rotation speed of the test wheel and the corresponding rotation speed of the real-time speed of the train is less than the preset speed error acceptance threshold.

[0125] 1. Measurement of rail-wheel adhesion state based on limit test.

[0126] (1) The measurement based on the limit acceleration test includes:

[0127] Apply an accelerating force to the test wheel. The accelerating force increases linearly with time, starting from 0 until it increases to the maximum accelerating force, and obtain the rotation speed of the test wheel and the vertical pressure of the test wheel in real time;

[0128] During the process that the accelerating force increases linearly with time, if the rotation speed of the test wheel suddenly changes and the rotation speed of the test wheel before the mutation does not reach the preset test wheel rotation speed threshold, obtain the time of the occurrence moment of the rotation speed mutation, and calculate the real-time rail-wheel adhesion coefficient according to the accelerating force value at this moment and the actual vertical pressure of the test wheel, and output triple data including the real-time rail-wheel adhesion coefficient to the on-vehicle control system;

[0129] If the rotation speed of the test wheel reaches the preset test wheel rotation speed threshold, or there is no sudden change in the rotation speed of the test wheel when the accelerating force increases to the maximum value, calculate the rail-wheel safe adhesion coefficient according to the maximum accelerating force and the vertical pressure of the test wheel; output triple data including the rail-wheel safe adhesion coefficient to the on-vehicle control system. In this process, the accurate real-time adhesion coefficient has not been measured yet, but it can be ensured that the actual rail-wheel adhesion coefficient is greater than the output result of the control center, meeting the requirements of risk-oriented safety;

[0130] Apply a braking force to the test wheel until the rotation speed of the test wheel drops to the rotation speed corresponding to the train speed, and then stop braking, which is regarded as a test cycle.

[0131] In this embodiment, if the rotation speed of the test wheel reaches the preset test wheel rotation speed threshold, or there is no sudden change in the rotation speed of the test wheel when the accelerating force increases to the maximum value, supplementary tests can be carried out on the assumption that the change range of the rail-wheel adhesion state of a rail transit line with a shorter length is relatively small, that is, reduce the vertical force applied by the pressure control device in the test, and then re-execute the measurement.

[0132] Measurements based on extreme acceleration tests can continuously execute multiple test cycles to measure the wheel-rail adhesion state that continuously changes along the running direction of rail transit. During continuous tests, a change in the accelerating force at the occurrence moment of the rotational speed mutation indicates a change in the wheel-rail adhesion state. The wheel-rail adhesion coefficient will be calculated by the control center and output to on-vehicle train control equipment to support functions such as adjusting the train protection curve and the train speed curve.

[0133] (2)Measurements based on extreme braking tests include:

[0134] Apply a braking force to the test wheel. The braking force increases linearly with time, starting from 0 until it increases to the maximum value, and the rotational speed of the test wheel and the vertical pressure of the test wheel are obtained in real time.

[0135] During the process where the braking force increases linearly with time, if the rotational speed of the test wheel mutates when the braking force increases to the maximum value, obtain the time at the occurrence moment of the rotational speed mutation, and calculate the real-time wheel-rail adhesion coefficient according to the braking force value at this moment and the actual vertical pressure of the test wheel, and output a triple data including the real-time wheel-rail adhesion state to the on-vehicle train control system.

[0136] If the rotational speed of the test wheel does not mutate when the braking force increases to the maximum value, calculate the wheel-rail safe adhesion coefficient according to the maximum braking force and the vertical pressure of the test wheel, and output a triple data including the wheel-rail safe adhesion coefficient to the on-vehicle train control system. In this process, an accurate real-time adhesion coefficient has not been measured, but it can be ensured that the actual wheel-rail adhesion coefficient is greater than the output result of the control center, meeting the requirements of risk-oriented safety.

[0137] Apply an accelerating force to the test wheel until the rotational speed of the test wheel increases to the rotational speed corresponding to the train speed, and then stop accelerating. This is regarded as a test cycle, and the wheel-rail adhesion state of a very short length of track can be accurately measured. The length of the test cycle depends on the speed measurement frequency of the speed measurement component, the accelerating force increase ability of the accelerating control, the braking ability of the braking control, etc.

[0138] In this embodiment, the wheel speed mutation is that the increase or decrease amplitude of the wheel speed exceeds the quadratic function change characteristic, and the preset test wheel rotational speed threshold is used as the judgment condition for the state to avoid the test wheel from continuously accelerating when there is no wheel speed mutation.

[0139] 2. Measurement of wheel-rail adhesion state based on target actions.

[0140] The target action is the traction or braking condition that the train intends to perform during operation. When the target action is performed, especially the high-level traction / braking condition, it is easy to encounter the unfavorable situation that the actual traction / braking force breaks through the adhesion. The wheel-rail adhesion state measurement based on the target action pre-tests the traction / braking condition that the train intends to perform through the wheel-rail adhesion state measurement device to determine the feasibility of the train's intended execution condition.

[0141] (1) Measurements based on target acceleration actions include:

[0142] Read the traction conditions that the train intends to implement and calculate the target acceleration force applied to the test wheel;

[0143] Apply an acceleration force to the test wheel, wherein the acceleration force increases linearly with time, starting from 0 until it reaches a target acceleration force, and after reaching the target acceleration force, maintains a preset time threshold, and obtains the rotation speed of the test wheel in real time;

[0144] If the test wheel speed suddenly changes, the real-time wheel-rail adhesion coefficient is calculated based on the acceleration force value at the moment of the test wheel speed sudden change and the actual vertical pressure of the test wheel, and the output is to the on-board control system: "The traction condition intended by the train is not feasible" and the triple data containing the real-time wheel-rail adhesion coefficient;

[0145] If the test wheel speed does not change suddenly, the information is output to the train's onboard control system: the traction condition that the train intends to implement is feasible;

[0146] Apply braking force to the test wheel until the speed of the test wheel drops to the speed corresponding to the train speed, and then stop braking.

[0147] (2) Measurements based on target braking actions include:

[0148] Read the braking condition that the train intends to implement and calculate the target braking force applied to the test wheel;

[0149] Apply a braking force to the test wheel, wherein the braking force increases linearly with time, starting from 0 until it reaches a target braking force, maintaining a preset time threshold, and obtaining the rotation speed of the test wheel in real time;

[0150] If the test wheel speed suddenly changes, the real-time wheel-rail adhesion coefficient is calculated according to the braking force value at the moment of the test wheel speed sudden change and the actual vertical pressure of the test wheel, and the output is to the on-board control system: "The braking condition intended by the train is not feasible" and the triple data containing the real-time wheel-rail adhesion coefficient;

[0151] If the test wheel speed does not change suddenly, the information is output to the train's onboard control system: the braking condition that the train intends to implement is feasible;

[0152] Apply an accelerating force to the test wheel until the rotational speed of the test wheel drops to the rotational speed corresponding to the train speed, and then stop braking.

[0153] In this embodiment, the sudden change in wheel speed is that the wheel speed drop exceeds the quadratic function change characteristic.

[0154] The following further elaborates on this application in combination with the attached drawings and specific embodiments.

[0155] The preparations before measuring the wheel-rail adhesion state of rail transit include: checking whether the device is in the retracted state through the control center. If it is in the retracted state, then convey an instruction to the position controller to control the pressure control component to make the device in a non-retracted state; the control center conveys an instruction to the pressure controller to control the pressure control component to apply a vertical force , and the default value of the magnitude is , where The default value of is 5, and other values can also be taken according to the mass of the device; is the mass of the wheel-rail adhesion state measuring device; is the acceleration due to gravity, and the value is 9.81 ; the control center reads the real-time speed of the train from the train on-board control system and position , and obtains the rotational speed of the test wheel through the speed sensor. If the rotational speed of the test wheel is not 0 and the relative error with the rotational speed corresponding to the real-time speed of the train is less than , then the test preparation work is completed. Among them, is the speed error acceptance threshold, and the default value is 5%, and other values can also be selected according to needs.

[0156] Figure 4 This is the schematic diagram of the measurement principle based on the extreme acceleration test in the embodiment of this application. In this embodiment, the measurement based on the extreme acceleration test includes:

[0157] S1. Complete the preparations before measuring the wheel-rail adhesion state of rail transit and start the test. Record the start time as , and the control center conveys an instruction to the acceleration controller to control the acceleration control component to apply an accelerating force to the test wheel, where the accelerating force increases linearly with time, starting from 0 until it increases to the maximum value . At the same time, the control center obtains the rotational speed of the test wheel in real time through the speed sensor, and the control center obtains the vertical pressure of the test wheel in real time through the pressure sensor. If the rotational speed of the test wheel suddenly changes and the rotational speed of the test wheel before the sudden change does not reach times the rotational speed of the test wheel corresponding to the maximum operating speed of the rail transit train, then go to step S2; otherwise (that is, the rotational speed of the test wheel reaches times the rotational speed of the test wheel corresponding to the maximum operating speed of the rail transit train, or the accelerating force When there is no sudden change in the test wheel speed when it increases to the maximum value, go to step S3. Among them, The default value of is 1.5, and other values not less than 1.1 can also be taken.

[0158] S2, record the discovery time of the sudden change in wheel speed as and the occurrence time of the sudden change in rotational speed as , calculate the acceleration force value at the moment according to the characteristics of the acceleration force applied by the acceleration control, and record it as , obtain the actual vertical pressure of the test wheel at the moment through a pressure sensor or calculate it by interpolation . The control center calculates the real-time wheel-rail adhesion coefficient as shown in Equation (4).

[0159]

[0160] The control center outputs triple data including the real-time wheel-rail adhesion state to the train on-board control system and executes step S4.

[0161] S3, record the acceleration force when it increases to the maximum value or the time when the test wheel speed reaches times the test wheel rotational speed corresponding to the maximum operating speed of the rail transit train as , the control center calculates the wheel-rail safety adhesion coefficient ' in real time as shown in Equation (5), and the control center outputs triple data including the real-time wheel-rail adhesion state to the train on-board control system . During this process, the rail transit wheel-rail adhesion state real-time measurement device has not measured the accurate real-time adhesion coefficient, but it can ensure that the actual wheel-rail adhesion coefficient is greater than the output result of the control center, meeting the requirements of risk-oriented safety. Execute step S4.

[0162]

[0163] S4, at the moment , the control center conveys an instruction to the brake controller to control the brake control to apply a braking force to the test wheel , the default value of is , and other values can also be taken. The control center obtains the rotational speed of the test wheel in real time through a speed sensor until the rotational speed of the test wheel drops to the rotational speed corresponding to the train speed, and the control center conveys an instruction to the brake controller to stop braking, and record the stop braking time as .

[0164] Figure 5 ​It is a schematic diagram of the change in the wheel-rail adhesion state based on the extreme acceleration test. In this embodiment, the measurement based on the extreme acceleration test can be continuously performed to measure the wheel-rail adhesion state that continuously changes along the running direction of the rail transit. During continuous testing, The change in the acceleration force at a certain moment indicates a change in the wheel-rail adhesion state. The wheel-rail adhesion coefficient will be calculated by the control center and output to the on-vehicle train control equipment to support functions such as the adjustment of the train protection curve and the adjustment of the train speed curve.

[0165] Figure 6 It is a schematic diagram of the measurement principle based on the extreme braking test of this application embodiment. In this embodiment, the measurement based on the extreme braking test includes:

[0166] S1, Prepare before measuring the wheel-rail adhesion state of the rail transit and start the test. Record the start time as , The control center conveys an instruction to the brake controller to control the brake control to apply a braking force to the test wheel , where the braking force increases linearly with time, starting from 0 until it increases to the maximum value . At the same time, the control center obtains the rotation speed of the test wheel in real time through the speed sensor, and the control center obtains the vertical pressure of the test wheel in real time through the pressure sensor . If the rotation speed of the test wheel suddenly changes when the braking force increases to the maximum value, then go to step S2; otherwise, go to step S3.

[0167] S2, Record the occurrence time of the wheel speed mutation as , the occurrence time of the rotation speed mutation as , calculate the braking force value at the moment of according to the characteristics of the braking force applied by the brake control, and record it as , obtain the actual vertical pressure of the test wheel at the moment of through the pressure sensor or by interpolation method. The control center calculates the real-time wheel-rail adhesion coefficient as shown in Equation (6).

[0168]

[0169] The control center outputs triple data containing the real-time wheel-rail adhesion coefficient to the on-vehicle train control system of the train , and execute step S4.

[0170] S3, Record the time when the braking force increases to the maximum value as , and the control center calculates the wheel-rail safe adhesion coefficient in real time 'As shown in Equation (7), the control center outputs triple data including the wheel-rail safety adhesion coefficient to the train on-board control system . During this process, the real-time measurement device for the wheel-rail adhesion state of rail transit has not measured the accurate real-time adhesion coefficient yet, but it can ensure that the actual wheel-rail adhesion coefficient is greater than the output result of the control center, meeting the requirements of risk-oriented safety. Step S4 is executed.

[0171]

[0172] S4. At time , the control center conveys an instruction to the acceleration controller to control the acceleration control component to apply an accelerating force to the test wheel . The value is defaulted to , and other values can also be taken. The control center obtains the rotation speed of the test wheel in real time through the speed sensor until the rotation speed of the test wheel increases to the rotation speed corresponding to the train speed. Then the control center conveys an instruction to the acceleration controller to stop accelerating, and records the stop acceleration time as .

[0173] The above steps are one test cycle, and the wheel-rail adhesion state of a very short length track can be accurately measured. The length of the test cycle depends on the speed measurement frequency of the speed measurement component, the accelerating force increasing ability of the acceleration control component, the braking ability of the braking control component, etc.

[0174] Figure 7 This is the schematic diagram of the measurement principle based on the target acceleration action in the embodiment of the present application. In this embodiment, the measurement based on the target acceleration action includes:

[0175] S1. The control center reads the traction working condition that the train intends to implement from the train on-board control system and calculates the target accelerating force applied to the test wheel, as shown in Equation (8).

[0176]

[0177] In the formula, is the vertical force applied by the pressure control component; is the traction force allocated to a single wheel of each power axle when the train runs under the target traction working condition; is the vertical pressure borne by a single wheel when the train runs in the no-load state.

[0178] S2. Complete the preparation before measuring the wheel-rail adhesion state of rail transit and start the test. Record the start time as . The control center conveys an instruction to the acceleration controller to control the acceleration control component to apply an accelerating force to the test wheel, where the accelerating force increases linearly with time, starting from 0 and increasing until it reaches the target accelerating force , the holding time after increasing to the target accelerating force , the preferred value is 1 second, and other values can also be selected. Meanwhile, the control center obtains the rotation speed of the test wheel in real time through the speed sensor. If there is a sudden change in the rotation speed of the test wheel, go to step S3; otherwise, go to step S4.

[0179] S3, record the current scenario as scenario 1. Record the discovery time of the wheel speed mutation as , and the occurrence time of the rotation speed mutation as , calculate the accelerating force value at according to the characteristics of the accelerating force applied by the accelerating control , obtain the actual vertical pressure of the test wheel at through the pressure sensor or calculate it by interpolation . The control center calculates the real-time wheel-rail adhesion coefficient as shown in Equation (4). The control center outputs two pieces of information to the train on-board control system: ① The traction condition intended to be implemented by the train is not feasible; ② The triple data including the real-time wheel-rail adhesion state . Execute step S5.

[0180] S4, record the current scenario as scenario 2. Record the time when the accelerating force increases to the target value , and add the holding time to get the time as . The control center outputs the information to the train on-board control system: The traction condition intended to be implemented by the train is feasible. Execute step S5.

[0181] S5, at the time of in scenario 1, or at the time of in scenario 2, the control center conveys an instruction to the brake controller to control the brake control to apply a braking force to the test wheel , the default value of the value taken is , and other values can also be taken. The control center obtains the rotation speed of the test wheel in real time through the speed sensor until the rotation speed of the test wheel drops to the rotation speed corresponding to the train speed, and then the control center conveys an instruction to the brake controller to stop braking.

[0182] Figure 8 is the schematic diagram of the measurement principle based on the target braking action in the embodiment of the present application. In this embodiment, the measurement based on the target braking action includes:

[0183] S1, the control center reads the braking condition intended to be implemented by the train from the train on-board control system and calculates the target braking force applied to the test wheel, as shown in Equation (9).

[0184]

[0185] In the formula, The vertical force applied by the pressure control component; The braking force allocated to a single wheel of each braking axle when the train operates under the target braking condition; The vertical pressure borne by a single wheel when the train operates in the unloaded state.

[0186] S2. Prepare before measuring the wheel-rail adhesion state of the rail transit and start the test. Record the start time as , the control center conveys an instruction to the brake controller to control the pressure control component to apply a braking force to the test wheel , where the braking force increases linearly with time, starting from 0 until it increases to the target braking force . After increasing to the target braking force, maintain the time , the preferred value is 1 second, and other values can also be selected. Meanwhile, the control center obtains the rotation speed of the test wheel in real time through the speed sensor. If the rotation speed of the test wheel shows a sudden change, go to step S3; otherwise, go to step S4.

[0187] S3. Record the current scenario as scenario 1. Record the discovery time of the wheel speed sudden change as , the occurrence time of the rotation speed sudden change as , calculate the braking force value at according to the characteristics of the braking force applied by the pressure control component, and record it as . Obtain the actual vertical pressure of the test wheel at through the pressure sensor or calculate it by the interpolation method . The control center calculates the real-time wheel-rail adhesion coefficient as shown in formula (6). The control center outputs two pieces of information to the train on-board control system: ① The braking condition intended to be implemented by the train is not feasible; ② The triple data including the real-time wheel-rail adhesion state . Execute step S5.

[0188] S4. Record the current scenario as scenario 2. Record the time when the braking force increases to the target value , and add the time after the holding time as . The control center outputs the information to the train on-board control system: The braking condition intended to be implemented by the train is feasible. Execute step S5.

[0189] S5. At the time in scenario 1, or at the time in scenario 2, the control center conveys an instruction to the brake controller to control the pressure control component to apply an accelerating force to the test wheel , and the value is defaulted to , other values can also be taken. The control center obtains the rotational speed of the test wheel in real time through the speed sensor until the rotational speed of the test wheel rises to the rotational speed corresponding to the train speed, and then the control center conveys an instruction to the acceleration controller to stop accelerating.

[0190] See the appendix Figure 9 , which shows a real-time measurement method for the wheel-rail adhesion state of rail transit for implementing the above method, including:

[0191] Obtain the real-time operating conditions of the train and the intended operating conditions to be executed by the train from the on-vehicle control system;

[0192] Use the wheel-rail adhesion state measurement device to perform the wheel-rail adhesion state measurement based on the limit test or the wheel-rail adhesion state measurement based on the target action according to the real-time operating conditions of the train and the intended operating conditions to be executed by the train.

[0193] In addition, an embodiment of the present application also provides a real-time measurement device for the wheel-rail adhesion state of rail transit, including:

[0194] An operating condition acquisition module that obtains the real-time operating conditions of the train and the intended operating conditions to be executed by the train from the on-vehicle control system;

[0195] A wheel-rail adhesion state measurement module that uses the wheel-rail adhesion state measurement device to perform the wheel-rail adhesion state measurement based on the limit test or the wheel-rail adhesion state measurement based on the target action according to the real-time operating conditions of the train and the intended operating conditions to be executed by the train.

[0196] Based on the same inventive concept, the present application also provides a computer-readable storage medium storing one or more programs, which can implement the aforementioned real-time measurement method for the wheel-rail adhesion state of rail transit when the one or more programs are executed.

[0197] As Figure 10 shown, an embodiment of the present application also provides a device, including a processor, a communication interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory communicate with each other through the communication bus.

[0198] The memory is a computer-readable storage medium for storing one or more programs.

[0199] The processor is used to execute the programs stored in the computer-readable storage medium.

[0200] This computer-readable storage medium can be included in the device / apparatus described in the above embodiment; or it can exist alone without being assembled into the device / apparatus.

[0201] Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A real-time measurement system for the wheel-rail adhesion state of rail transit, characterized in that, Comprising: A wheel-rail adhesion state measuring device and an on-vehicle control system; The wheel-rail adhesion state measuring device is installed on the train and is connected to the on-vehicle control system; The wheel-rail adhesion state measuring device performs wheel-rail adhesion state measurement based on an extreme test or wheel-rail adhesion state measurement based on a target action according to the real-time operating condition of the train and the intended operating condition of the train obtained from the on-vehicle control system; Wherein, the wheel-rail adhesion state measuring device is further configured to calculate and obtain a real-time wheel-rail adhesion coefficient or a wheel-rail safe adhesion coefficient by performing wheel-rail adhesion state measurement based on an extreme test, and output triple data including the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient to the on-vehicle control system; and, The wheel-rail adhesion state measuring device is further configured to judge the feasibility of the intended operating condition of the train by performing wheel-rail adhesion state measurement based on a target action, and output a judgment result to the on-vehicle control system; Wherein, the wheel-rail adhesion state measurement based on an extreme test includes: measurement based on an extreme acceleration test and measurement based on an extreme braking test; and, The wheel-rail adhesion state measurement based on a target action includes: measurement based on a target acceleration action and measurement based on a target braking action.

2. The system according to claim 1, wherein If the real-time operating condition of the train is a traction condition or a non-traction and non-braking condition, then perform measurement based on an extreme acceleration test; If the real-time operating condition of the train is a braking condition, then perform measurement based on an extreme braking test.

3. The system according to claim 1, wherein If the train intends to perform a traction condition, then perform measurement based on a target acceleration action; If the train intends to perform a braking condition, then perform measurement based on a target braking action.

4. The system according to any one of claims 1-3, wherein The physical structure of the wheel-rail adhesion state measuring device includes: a fixing component, a pressure control component, a connecting component, a test wheel, an acceleration control component, a braking control component and a speed measuring component.

5. The system according to claim 4, wherein The control structure of the wheel-rail adhesion state measuring device includes: a control center, a speed detector, a pressure detector, a braking controller, an acceleration controller, a pressure controller and a position controller; wherein, the control center is connected to the on-vehicle control system, the speed detector is connected to the speed measuring component, the pressure detector, the pressure controller and the position controller are connected to the pressure control component, the braking controller is connected to the braking control component, and the acceleration controller is connected to the acceleration control component.

6. A real-time measurement method for the wheel-rail adhesion state of rail transit, characterized in that, The method includes: Obtain the real-time operating condition of the train and the intended operating condition of the train from the on-vehicle control system; Use the wheel-rail adhesion state measuring device to perform wheel-rail adhesion state measurement based on an extreme test or wheel-rail adhesion state measurement based on a target action according to the real-time operating condition of the train and the intended operating condition of the train; Among them, by performing the measurement of the wheel-rail adhesion state based on the limit test, the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient is calculated and a triple data including the real-time wheel-rail adhesion coefficient or the wheel-rail safe adhesion coefficient is output to the on-vehicle control system; and, By performing the measurement of the wheel-rail adhesion state based on the target action, the feasibility of the working condition that the train intends to execute is judged and the judgment result is output to the on-vehicle control system; Among them, the measurement of the wheel-rail adhesion state based on the limit test includes: the measurement based on the limit acceleration test and the measurement based on the limit braking test; and, The measurement of the wheel-rail adhesion state based on the target action includes: the measurement based on the target acceleration action and the measurement based on the target braking action.

7. The method according to claim 6, characterized in that, If the real-time running condition of the train is the traction condition or the non-traction and non-braking condition, the measurement based on the limit acceleration test is performed; If the real-time running condition of the train is the braking condition, the measurement based on the limit braking test is performed.

8. The method according to claim 6, characterized in that, If the train intends to execute the traction condition, the measurement based on the target acceleration action is performed; If the train intends to execute the braking condition, the measurement based on the target braking action is performed.

9. A computer-readable storage medium storing one or more programs, characterized in that, When the one or more programs are executed, the real-time measurement method of the rail transit wheel-rail adhesion state according to any one of claims 6-8 can be implemented.

10. An electronic device, comprising a processor, a communication interface, the computer-readable storage medium according to claim 9, and a communication bus; wherein, The electronic communication among the processor, the communication interface, and the computer-readable storage medium through the communication bus; characterized in that, The processor is used to execute the program stored in the computer-readable storage medium.

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