Railway vehicle running safety evaluation method, railway vehicle running safety evaluation device, and railway vehicle running safety evaluation program

Abstract

This provides a low-cost, versatile method for evaluating the running safety of railway vehicles. [Solution] A method for evaluating the running safety of a railway vehicle is the wheelset yaw angular velocity Ψ W The first lateral pressure component ΔQ1 acting between the wheel and rail is calculated from (dot) and velocity V, and the left-right vibration acceleration y of the wheel axle is calculated. W The second lateral pressure component ΔQ2 acting between the wheel and rail is calculated from (two dots), and the wheel axle yaw angular velocity Ψ is calculated. W The third lateral pressure component ΔQ3 related to the torsion of the air spring is calculated from (dot) and velocity V, and the wheel axle yaw angular velocity Ψ is calculated. W The fourth lateral pressure component ΔQ4 acting between the wheel and the rail is calculated from the slope C which is linearly related to the lateral pressure fluctuation component of the wheel (dot), the fifth lateral pressure component ΔQ5 is calculated from the contact position x between the wheel and the rail and the wheel load P, and the lateral pressure Q is estimated by adding the first lateral pressure component ΔQ1 to the fifth lateral pressure component ΔQ5, and the vertical displacement Z of the axle spring 1L , Z 1R Based on the lateral pressure Q, the wheel load P is estimated, and the running safety of the railway vehicle is evaluated based on the derailment coefficient Q / P.

Description

[Technical Field]

[0001] This invention relates to a method for evaluating the running safety of railway vehicles, a device for evaluating the running safety of railway vehicles, and a program for evaluating the running safety of railway vehicles. [Background technology]

[0002] As a method for evaluating the running safety of railway vehicles, which is their safety against derailment, evaluation methods using the PQ axis are widely used. Non-patent document 1 discloses a method for improving the safety of a vehicle by using a PQ axis with strain gauges installed on the wheels as a way to evaluate the running safety of a vehicle.

[0003] In the evaluation method using the PQ axis, the wheel load P, which is the vertical force acting at the contact point between the wheel and the rail to which strain gauges are attached, and the lateral force Q, which is the horizontal force, are measured, and the derailment coefficient (Q / P), which is the value obtained by dividing the lateral force Q by the wheel load P, is used to evaluate running safety. However, the manufacture of the PQ axis is time-consuming, and the cost of replacing it is high. In addition, there are limitations on the allowable braking force in order to protect the strain gauges attached to the PQ axis from heat.

[0004] As an evaluation method that does not use the PQ axis, Non-Patent Document 2 discloses a method for evaluating running safety using only the vibration acceleration of the train body. This method only requires the installation of an accelerometer, so it can evaluate running safety at a lower cost compared to the method that uses the PQ axis. However, this method can only be applied to low-speed ranges or speed increase tests with small speed increases, and lacks versatility.

[0005] Furthermore, as an alternative evaluation method that does not use the PQ axis, Patent Document 1 discloses a method for evaluating running safety using a PQ monitoring bogie. In this method, the derailment coefficient (Q / P) can be constantly monitored during commercial operation, but it is necessary to prepare a dedicated bogie for each train being evaluated, and it is not possible to evaluate running safety by applying it to different bogies, which increases costs. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2020-185876 [Non-patent literature]

[0007] [Non-Patent Document 1] "Manual and Commentary on Tests to Improve Operating Speeds for Conventional Railways," supervised by the Railway Bureau of the Ministry of Transport, edited by the Railway Technical Research Institute, Railway Technical Research Institute Foundation, pp. 67-76, 1993. [Non-Patent Document 2] "Manual and Commentary on Tests to Improve Operating Speed ​​for Conventional Railways," supervised by the Railway Bureau of the Ministry of Transport and edited by the Railway Technical Research Institute, Railway Technical Research Institute Foundation, pp. 117-124, 1993. [Overview of the project] [Problems that the invention aims to solve]

[0008] As described above, evaluation methods using a PQ axis or PQ monitoring cart are costly, while evaluation methods that do not use a PQ axis are limited to specific tests and lack versatility.

[0009] This invention has been made in view of the above circumstances, and aims to provide a low-cost and highly versatile method for evaluating the running safety of railway vehicles, a running safety evaluation device, and a running safety evaluation program without using a PQ axis. [Means for solving the problem]

[0010] One aspect of the present invention is a method for evaluating the running safety of a railway vehicle, comprising the steps of: detecting information about the bogie of a running railway vehicle; calculating a first lateral pressure component relating to the frictional force acting between the inner rail wheel and the rail based on the wheel axle yaw angular velocity and speed of the bogie; calculating a second lateral pressure component relating to the centrifugal force acting between the outer rail wheel and the rail based on the wheel axle lateral vibration acceleration; calculating a third lateral pressure component relating to the torsion of the air spring between the bogie and the vehicle body based on the wheel axle yaw angular velocity and speed; and calculating the wheel axle yaw angular velocity and the lateral pressure fluctuation component of the outer rail wheel and positive The method includes the steps of: calculating a fourth lateral pressure component acting between the outer rail wheel and the rail based on a linearly related slope; calculating a fifth lateral pressure component relating to the contact position based on the contact position between the outer rail wheel and the rail and the outer rail wheel load; estimating the lateral pressure acting between the outer rail wheel and the rail by adding up all of the first to fifth lateral pressure components; estimating the wheel load based on the axle spring vertical displacement and the lateral pressure; calculating the derailment coefficient by dividing the lateral pressure by the wheel load; and evaluating the running safety of the railway vehicle based on the derailment coefficient.

[0011] Furthermore, one aspect of the present invention, a railway vehicle running safety evaluation device, includes: a detection unit that detects information about the bogie of a running railway vehicle; a first calculation unit that calculates a first lateral pressure component relating to the frictional force acting between the inner rail wheel and the rail based on the wheel axle yaw angular velocity and speed of the bogie; a second calculation unit that calculates a second lateral pressure component relating to the centrifugal force acting between the outer rail wheel and the rail based on the wheel axle left-right vibration acceleration; a third calculation unit that calculates a third lateral pressure component relating to the twisting of the air spring between the bogie and the vehicle body based on the wheel axle yaw angular velocity and speed; and the wheel axle yaw angular velocity and the static wheel load of the outer rail wheel and positive The system comprises: a fourth calculation unit that calculates a fourth lateral pressure component acting between the outer rail wheel and the rail based on the linear relationship between the slope and the rail; a fifth calculation unit that calculates a fifth lateral pressure component relating to the contact position based on the contact position between the outer rail wheel and the rail and the outer rail wheel load; a lateral pressure estimation unit that estimates the lateral pressure acting between the outer rail wheel and the rail by adding up all of the first to fifth lateral pressure components; a wheel load estimation unit that estimates the wheel load based on the axle spring vertical displacement and the lateral pressure; a calculation unit that calculates the derailment coefficient by dividing the lateral pressure by the wheel load; and an evaluation unit that evaluates the safety of the railway vehicle based on the derailment coefficient.

[0012] Furthermore, the railway vehicle running safety evaluation program, which is one aspect of the present invention, includes the steps of: detecting information about the bogie of a running railway vehicle; calculating a first lateral pressure component relating to the frictional force acting between the inner rail wheel and the rail based on the yaw angular velocity and speed of the bogie's axle; calculating a second lateral pressure component relating to the centrifugal force acting between the outer rail wheel and the rail based on the lateral vibration acceleration of the axle; calculating a third lateral pressure component relating to the twisting of the air spring between the bogie and the vehicle body based on the yaw angular velocity and speed; and the axle yaw angular velocity and the static wheel load of the outer rail wheel. The method includes the steps of: calculating a fourth lateral pressure component acting between the outer rail wheel and the rail based on a positive linear relationship between the slope and the rail; calculating a fifth lateral pressure component relating to the contact position based on the contact position between the outer rail wheel and the rail and the outer rail wheel load; estimating the lateral pressure acting between the outer rail wheel and the rail by adding up all of the first to fifth lateral pressure components; estimating the wheel load based on the axle spring vertical displacement and the lateral pressure; calculating the derailment coefficient by dividing the lateral pressure by the wheel load; and evaluating the running safety of the railway vehicle based on the derailment coefficient. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a low-cost and highly versatile method for evaluating the running safety of railway vehicles, a running safety evaluation device, and a running safety evaluation program without using a PQ axis. [Brief explanation of the drawing]

[0014] [Figure 1] Figure 1 is a schematic diagram illustrating a railway vehicle to which the railway vehicle running safety evaluation method according to this embodiment is applied. [Figure 2] Figure 2 is a block diagram showing the control configuration of the railway vehicle running safety evaluation device according to this embodiment. [Figure 3] Figure 3 is a flowchart showing the control flow for estimating lateral pressure and wheel load. [Figure 4] Figure 4 shows various dimensions when a railway vehicle passes through a curve. [Figure 5]Figure 5 shows the time variation of lateral pressure, wheel load, wheelset yaw angular velocity, bogie frame yaw angular velocity, and wheel / rail relative left-right displacement. [Figure 6] Figure 6 shows examples of simulation waveforms for lateral pressure and wheelset yaw angular velocity, as well as the locations where the increase amounts are read. [Figure 7] Figure 7 shows the relationship between the wheelset yaw angular velocity and the increase in lateral pressure. [Figure 8] Figure 8 shows the relationship between the stationary wheel load and the inclination shown by the linear approximation in Figure 7. [Figure 9] Figure 9 is an explanatory diagram illustrating the comparison between estimated and measured values ​​of lateral pressure and wheel load. [Figure 10] Figure 10 shows an example of a monitor screen for software operating using the railway vehicle running safety evaluation program according to this embodiment. [Figure 11] Figure 11 shows an example of a monitor screen for software operating using the railway vehicle running safety evaluation program according to this embodiment. [Figure 12] Figure 12 shows an example of a monitor screen for software operating using the railway vehicle running safety evaluation program according to this embodiment. [Modes for carrying out the invention]

[0015] The running safety evaluation method, running safety evaluation device 100, and running safety program of the railway vehicle 1 according to this embodiment will be described below with reference to the drawings.

[0016] In the following explanation, the wheelset yaw angular velocity will be referred to as "Ψ". W (dot) is referred to as "Ψ W (dot) is Psychic WΨ W This indicates that a "·" is placed at the top of the symbol. Also, the lateral vibration acceleration of the wheel axle is called "y W (Two dots) is referred to as "y W (Two dots) is YW W This indicates that "··" is attached to the beginning of the character.

[0017] <Vehicle Structure> The railway vehicle 1 to which the running safety evaluation method of this embodiment is applied will be described with reference to Figure 1.

[0018] The railway vehicle 1 comprises a bogie 10 and a car body 30. In Figure 1, for the sake of clarity, the car body 30 is shown floating vertically above the bogie 10.

[0019] [Cart] The bogie 10 comprises a bogie frame 11, a wheelset 12, bearings 13, axle boxes 14, axle box support devices 15, axle springs 16, a 6-axis sensor 18, and a laser displacement meter 19.

[0020] The bogie frame 11 is a structural member that constitutes the main body of the bogie 10. The bogie frame 11 is constructed by connecting a pair of left and right side beams 21 that extend in the longitudinal direction and are spaced apart in the sleeper direction, with a cross beam 22 that extends in the sleeper direction at the center in the longitudinal direction. The wheelsets 12 are attached to the bogie frame 11 via axle box support devices 15 and axle boxes 14. An air spring 25 is attached to the upper part of the bogie frame 11, which is interposed between the bogie 10 and the car body 30 to dampen vibrations transmitted from the bogie 10 to the car body 30.

[0021] The wheelset 12 is constructed by incorporating the left and right wheels 23, which roll on the track (rail), into both ends of a cylindrical axle 24. A pair (2 axles) of wheelsets 12 are provided on the bogie frame 11, spaced apart in the front-rear direction.

[0022] The axle box 14 rotatably supports the axle 24 by bearings 13 formed at both ends of the wheelset 12. The axle box 14 has a speed generator (not shown) that outputs a vehicle speed signal corresponding to the rotational speed of the wheelset 12.

[0023] The axle box support device 15 supports the axle box 14 so that it can be displaced relative to the bogie frame 11 in the vertical, roll, and steering (yaw) directions.

[0024] The axle spring 16 is provided between the bogie frame 11 and the axle box support device 15, and generates a spring reaction force corresponding to the relative vertical displacement between the bogie frame 11 and the axle box 14.

[0025] The 6-axis sensor 18 is attached to either the left or right axle box 14 of the bogie 10 and measures the acceleration of the axle box 14 in the longitudinal, lateral, and vertical directions, as well as the angular velocity of the axle box 14 in the roll, pitch, and yaw directions.

[0026] The laser displacement sensor 19 is attached to the side beam 21 and is a sensor that measures the vertical displacement of the shaft spring 16.

[0027] [Vehicle body] The car body 30 is a structure provided on top of two bogie frames 11 that are spaced apart in the longitudinal direction of the railway vehicle 1. The car body 30 is the part that accommodates the driver, passengers, etc., and is formed in a predetermined box shape.

[0028] The vehicle body 30 includes a speed sensor 31, a data logger 32, and a control unit 33.

[0029] The speed sensor 31 is the aforementioned speed generator that outputs a vehicle speed signal corresponding to the rotational speed of the wheelset 12. Although its actual mounting position is the axle box 14, the vehicle speed signal is transmitted to the speedometer displayed in the driver's cab of the vehicle body 30, and this vehicle speed signal is used, so for convenience, it will be explained as being installed on the vehicle body 30.

[0030] The data logger 32 is the part that receives signals transmitted from the speed sensor 31, the 6-axis sensor 18, and the laser displacement meter 19 and stores them in an internal storage device.

[0031] The control unit 33 receives signals transmitted from the data logger 32 and performs predetermined control. The details of the control will be described later.

[0032] <Control Configuration> The control configuration of the running safety evaluation device 100 for the railway vehicle 1 according to this embodiment will be described with reference to the block diagram in Figure 2.

[0033] The running safety evaluation device 100 of the railway vehicle 1 includes a detection unit 41 and a control unit 33.

[0034] The detection unit 41 includes a speed sensor 31, a six-axis sensor 18, a laser displacement meter 19, and a data logger 32.

[0035] As described above, the speed sensor 31 measures the speed V of the railway vehicle 1 and transmits it to the data logger 32.

[0036] The six-axis sensor 18 measures, in particular, the axle yaw angular velocity Ψ W (dot) and the axle left-right vibration acceleration y W (double dot) of the railway vehicle 1 and transmits them to the data logger 32.

[0037] The laser displacement meter 19 measures, in particular, the up-down displacement Z 1L , Z 1R of the left and right axle springs of the railway vehicle 1 and transmits it to the data logger 32.

[0038] The data logger 32 receives the speed V, the axle yaw angular velocity Ψ W (dot), the axle left-right vibration acceleration y W (double dot), and the up-down displacement Z 1L , Z 1R of the left and right axle springs of the railway vehicle 1, stores them in an internal storage device, and transmits them to the control unit 33.

[0039] The control unit 33 can be realized, for example, by a CPU (Central Processing Unit), a working memory, and a non-volatile storage device storing a control program. Note that the control unit 33 may be realized using a user-programmable integrated circuit such as an FPGA (field-programmable gate array) or a microcomputer.

[0040] The control unit 33 controls the running safety evaluation device 100 of the railway vehicle 1 by executing a control application program (not shown) stored in a memory (not shown), and also functions as a lateral pressure / wheel load estimation unit 34 and an evaluation unit 35. The lateral pressure / wheel load estimation unit 34 has a lateral pressure estimation unit 34a and a wheel load estimation unit 34b, as will be described later.

[0041] The lateral pressure and wheel load estimation unit 34 estimates the lateral pressure and wheel load of the railway vehicle and transmits the estimation results to the evaluation unit 35.

[0042] The evaluation unit 35 evaluates the running safety of the railway vehicle 1 according to a program stored in the internal memory unit 36, based on the results calculated by the lateral pressure / wheel load estimation unit, the obtained data, and the vehicle specifications etc. 37, and outputs the result 38.

[0043] <Control Flow> The control flow when the control unit 33 functions as a lateral pressure / wheel load estimation unit 34 will be explained with reference to the flowchart in Figure 3.

[0044] In the flowchart of Figure 3, the control flow of the lateral pressure estimation unit 34a of the lateral pressure / wheel load estimation unit 34 is shown on the left side of the page, and the control flow of the wheel load estimation unit 34b of the lateral pressure / wheel load estimation unit 34 is shown on the right side of the page. The control unit 33 receives the detected values: speed V and the wheel axle yaw angular velocity Ψ of the railway vehicle 1. W (dot), wheelset left-right vibration acceleration y W (Two dots) and left and right axis spring vertical displacement Z 1L , Z 1R Based on this, the lateral pressure Q and wheel load P are estimated by performing calculations on these values.

[0045] [Estimation of wheel load P] This section explains how to estimate the wheel load P.

[0046] The control unit 33 estimates the wheel load P from the following equation (1) based on the balance of vertical forces acting on the wheelset 12 and the balance of moments acting on the wheelset 12.

[0047]

number

[0048] Here, the subscript L、R The left-right position of the wheel 23 and axle spring 16 is indicated. Also, P0 is the static wheel load, Fz is the change in the vertical force of the axle spring from the stationary state, Q is the lateral pressure, b0 is half the wheel / rail contact point distance, b1 is half the axle spring distance, r w is the wheel radius. Fz is the vertical displacement of the axle spring Z. 1L , Z 1R The vertical stiffness of the axle spring k 1Z It can be found by multiplying by .

[0049] Furthermore, if the lateral pressure Q described below is used, the vertical displacement Z of the shaft spring can be calculated without following equation (1) above. 1L , Z 1R Only the vertical stiffness k of the shaft spring is measured there. 1Z The wheel load P can be estimated by multiplying the result by the estimated lateral pressure.

[0050] Note that the calculation process shown in Figure 3 is repeated, for example, every 10ms, but the lateral pressure Q used as described above refers to the lateral pressure Q estimated by the previous calculation process (for example, 10ms ago). In other words, in the initial state where the wheel load P has not yet been estimated, the lateral pressure Q is set to 0, and the wheel load P is first estimated from equation (1) above. This wheel load P is then used to estimate the lateral pressure Q in the next step, and this lateral pressure Q is then used to estimate the wheel load P as shown in Figure 3 in the next step.

[0051] [Estimation of lateral pressure Q] This section explains how to estimate the lateral pressure Q.

[0052] The control unit 33 determines five lateral pressure components ΔQ1 to ΔQ5 that are thought to affect the lateral pressure Q, and estimates the lateral pressure Q by adding them all together.

[0053] (ΔQ1(frictional force)) The first lateral pressure component ΔQ1 is the lateral pressure due to friction. Lateral pressure due to friction is the resistance force between the inner rail wheel and rail that acts when traveling on a curve.

[0054] The first lateral pressure component ΔQ1 can be calculated from the following equation (2).

[0055]

number

[0056] Here, P in γ is the inner rail wheel load P, and the previously estimated wheel load P is used. Also, κ is the inner rail lateral pressure wheel load ratio equivalent to the friction coefficient between the wheel and rail, and is determined in advance as a function whose value changes according to the curvature through vehicle motion simulation. γ is a variable that depends on the speed V, and is given such that it becomes smaller as the speed V increases. γ can be obtained from the following equation (3).

[0057]

number

[0058] Here, μ V0 μ is the coefficient of friction when V=0. V Considering the speed dependence of the coefficient of friction, the following equation (4), which is the relationship between the coefficient of friction and speed V in a dry state, is used.

[0059]

number

[0060] However, the maximum value of γ is set to 1.05. Here, the friction coefficient μ between the wheel and rail has a large effect on steady-state lateral pressure, but it is small, around 0.1 in rainy weather, and can be as large as 0.55 in in-yard running tests in sunny weather. Since the actual friction coefficient during running is unknown, the friction coefficient μ is set to a higher value in dry conditions to ensure a safe evaluation.

[0061] Furthermore, as shown in Figure 3, the curvature is the wheel-shaft yaw angular velocity Ψ W It can be calculated by dividing (dot) (rad / s) by the velocity V (m / s).

[0062] From the above, the first lateral pressure component ΔQ1 is equal to the wheel axle yaw angular velocity Ψ W It is determined based on (dot) and velocity V.

[0063] In other words, as shown in Figure 3, the control unit 33 controls the wheel axle yaw angular velocity Ψ W Divide (dot) by velocity V to find the curvature. Apply a low-pass filter (LPF(1), cutoff frequency f) to the curvature. c After applying a 3Hz test, the inner rail lateral pressure wheel load ratio κ is determined from a function whose value changes according to the previously determined curvature. Based on equation (3), the variable γ corresponding to the speed V is determined. Substituting each value into equation (2), the first lateral pressure component ΔQ1 is obtained.

[0064] (ΔQ² (centrifugal force)) The second lateral pressure component ΔQ2 is centrifugal force.

[0065] The second lateral pressure component ΔQ2 can be calculated from the following equation (5).

[0066]

number

[0067] Here, α U y is the excess centrifugal acceleration, and y is the lateral vibration acceleration of the wheel axle. W (Two dots) Low-pass filter processing (LPF(2), cutoff frequency f c This is the lateral acceleration of the shaft box after (=0.1Hz). st is the stationary wheel load, and g is the acceleration due to gravity; both are known values.

[0068] From the above, the second lateral pressure component ΔQ2 is the wheel axle left-right vibration acceleration y, as shown in Figure 3. W It is determined based on (two dots).

[0069] (ΔQ3 (torsion of the air spring)) The third lateral pressure component ΔQ3 is the torsion of the air spring 25.

[0070] When a vehicle is traveling on a curved section, a bogie angle (relative yaw angle) is generated between the car body and the bogie. In this state, the twisting of the air spring 25 generates a bogie rotation moment, and a lateral pressure component ΔQ3 is generated on the outer rail side of the leading axle.

[0071] The third lateral pressure component ΔQ3 can be calculated from the following equation (6).

[0072]

number

[0073] Here, as shown in Figure 4, k 2X 2b2 is the longitudinal stiffness of the air spring 25, 2b2 is the distance between the left and right air springs, 2L is the distance between the bogie centers, 2a T Ψ is the wheelbase, and both are known values. R is the radius of curvature, and Ψ is the wheelset yaw angular velocity. W It can be calculated from (dot) and velocity V.

[0074] From the above, the third lateral pressure component ΔQ3 is equal to the wheel axle yaw angular velocity Ψ W It can be calculated from (dot) and velocity V.

[0075] In other words, the third lateral pressure component ΔQ3 is the wheel axle yaw angular velocity Ψ, as shown in Figure 3. W The curvature, which is the reciprocal of the curve radius R obtained from (dot) and velocity V, is subjected to a low-pass filter, and the values ​​are substituted into the above equation (6) to obtain the result.

[0076] (ΔQ4 (variable component)) The fourth lateral pressure component ΔQ4 is a fluctuating component.

[0077] The fourth lateral pressure component ΔQ4 can be calculated from the following equation (7).

[0078]

number

[0079] Here, C is the wheel-axle yaw angular velocity Ψ W This slope represents the relationship between (dot) and the increase in lateral pressure; details will be explained later. Ψ W The dot represents the wheelset yaw angular velocity.

[0080] From the above, the fourth lateral pressure component ΔQ4 is equal to the wheel axle yaw angular velocity Ψ W It can be found from (dot).

[0081] In other words, as shown in Figure 3, the fourth lateral pressure component ΔQ4 is equal to the wheel axle yaw angular velocity Ψ W The result is obtained by applying a bandpass filter (BPF, bandwidth f=3~10Hz) to (dot) and multiplying it by the slope C.

[0082] (ΔQ5 (Apparent lateral pressure due to wheel contact position)) The fifth lateral pressure component ΔQ5 is a fluctuating component.

[0083] The fifth lateral pressure component ΔQ5 can be calculated from the following equation (8).

[0084]

number

[0085] Here, P out is the wheel load on the outer rail, and the previously estimated wheel load P is used. x is the wheel / rail contact position. The wheel / rail contact position x is given in advance as a function whose value changes according to the curvature through simulation. Note that the effect of the load position on the wheel load output is small and therefore ignored.

[0086] From the above, the fifth lateral pressure component ΔQ5 is equal to the wheel axle yaw angular velocity Ψ W It can be calculated from (dot) and velocity V.

[0087] In other words, as shown in Figure 3, the fifth lateral pressure component ΔQ5 is equal to the wheel axle yaw angular velocity Ψ WAfter applying a low-pass filter (LPF(1)) to the curvature obtained from (dot) and velocity V, the wheel / rail contact position x, whose value changes according to the previously determined curvature, and the wheel load P on the outer rail side are obtained. out It can be obtained by multiplying by .

[0088] [Wheel load P, lateral force Q] Once the first to fifth lateral pressure components are determined, they are all added together to calculate the estimated lateral pressure Q. As shown in Figure 3, the estimated lateral pressure Q is used to estimate the wheel load P and is substituted into equation (1) above. Furthermore, by dividing the estimated lateral pressure Q by the estimated wheel load P, the derailment coefficient Q / P can be estimated.

[0089] [Slope C] Here, the axle yaw angular velocity Ψ used in the fourth lateral pressure component ΔQ4 described above is W This section explains the slope C, which represents the relationship between (dot) and the increase in lateral pressure.

[0090] In estimating the fourth lateral pressure component ΔQ4 described above, it is necessary to use a component with a high correlation between lateral pressure Q and behavior in order to improve estimation accuracy. Figure 5 shows the lateral pressure Q, wheel load P, and wheel axle yaw angular velocity Ψ when a sinusoidal street displacement is continuously applied in a bench test. W (Dot), Bogie frame yaw angular velocity and wheel / rail wheel relative left-right displacement Y rel This shows the time variation (mm).

[0091] As shown in Figure 5, the behavior that shows the highest correlation with the change in lateral pressure Q is the wheel axle yaw angular velocity Ψ. W It can be seen that it is a dot. In particular, the area enclosed by the dashed circle is the wheel axle yaw angular velocity Ψ W The (dot) closely resembles the fluctuation of the lateral pressure Q. Therefore, the fourth lateral pressure component ΔQ4 is estimated using the wheel axle yaw angular velocity Ψ. W It is assumed that using a dot () is appropriate.

[0092] Figure 6 shows the lateral pressure Q and the wheelset yaw angular velocity Ψ. WThis figure shows an example of a simulation waveform (dot) and the location where the increase is read. Figure 6 shows the wheelset yaw angular velocity Ψ when railway vehicle 1 passes through a curved section. W (Dot) and outer rail side lateral pressure Q out The correlation of the fluctuating components is shown. Specifically, when a railway vehicle 1 is subjected to a displacement over a time of 15 seconds while passing through a curved section, the lateral pressure Q on the outer rail side is shown. out The axle yaw angular velocity Ψ increases by a, and at the same time, W The (dot) has increased by b.

[0093] This simulation is repeated many times, and each result is used to determine the wheel axle yaw angular velocity Ψ. W Figure 7 plots the relationship between (dots) and the increase in lateral pressure. Each circle represents the result obtained from one simulation. Note that in Figure 7, only data for R1000, the largest curve radius in the simulation, is shown to ensure a conservative estimate. From the data obtained in this way, the wheelset yaw angular velocity Ψ W Linear approximation of the relationship between (dot) and the increase in lateral pressure gives a slope C of 3.3 [kN / (deg / s)].

[0094] Furthermore, the inclination C is a vehicle specification, particularly the vehicle body mass M. B It is affected by the vehicle body mass M. B In the case of a railway vehicle 1 weighing 23,200 kg, the static wheel load P is calculated when the vehicle body mass is 0.5 times, 1.0 times, and 1.5 times. st These values ​​are 25kN, 39kN, and 53kN, respectively. From this, the stationary wheel load P st And the wheel axle yaw angular velocity Ψ W The relationship between the slope C, which represents the relationship between (dot) and the increase in lateral pressure, is shown in Figure 8, and this relationship can be expressed by the following equation (9).

[0095]

number

[0096] Therefore, the fluctuating component, which is the fourth lateral pressure component ΔQ4, is given by equation (9) with the stationary wheel load Pst The slope C obtained by substituting this value into equation (7) can be found by substituting it into equation (7).

[0097] As described above, the lateral pressure Q and wheel load P can be estimated. Furthermore, by dividing the lateral pressure Q by the wheel load P, the derailment coefficient Q / P, which is an indicator of the running safety of railway vehicles, can be estimated.

[0098] <Validity of the estimation results> The validity of the estimation results will be explained. Figure 9 is an explanatory diagram illustrating the comparison between the estimated values ​​of lateral pressure Q and wheel load P and the measured values.

[0099] On the left side of Figure 9, from top to bottom, time-series data are shown for the fourth lateral pressure component ΔQ4 (estimated value), the other first to third and fifth lateral pressure components ΔQ1, ΔQ2, ΔQ3, and ΔQ5 (estimated values), and the sum of all of these, which is lateral pressure Q (estimated and measured values). For lateral pressure Q, the graph is shown with overlapping time-series data to demonstrate how well the estimated value using the above method simulates the measured value on the PQ axis. Note that this measured value has been subjected to a low-pass filter with a cutoff frequency of 20 Hz.

[0100] The estimated value of lateral pressure Q is in close agreement with the measured value, indicating that the estimation method for evaluating the running safety of the railway vehicle 1 in this embodiment is valid.

[0101] Similarly, on the right side of the page, graphs are shown of the measured and estimated values ​​of wheel load P and derailment coefficient Q / P, with the time-series data overlapping. For these two indicators as well, the measured and estimated values ​​are in close agreement, indicating that the estimation method for evaluating the running safety of the railway vehicle 1 in this embodiment is valid.

[0102] <Driving Safety Evaluation Software> The evaluation software for performing the running safety evaluation method of the railway vehicle 1 according to this embodiment will be described with reference to Figures 2 and 10 to 12.

[0103] The evaluation software functions as an evaluation unit 35 within the control unit 33 shown in Figure 2 and is executed according to a program stored in the memory unit 36 ​​or the like. Based on various data acquired from the detection unit 41 and vehicle specifications, the evaluation software outputs evaluation results such as the derailment coefficient Q / P as a measure of running safety.

[0104] As shown in Figures 10 to 12, the evaluation software has the function of displaying at least three screens: A) "Settings and Data Input Screen" (corresponding to Figure 10), B) "Estimated Waveform Display Screen" (corresponding to Figure 11), and C) "Target Value Exceed List Screen" (corresponding to Figure 12). On A) "Settings and Data Input Screen," the user inputs information such as pre-known vehicle specifications, target values ​​such as lateral pressure Q, and mileage, and loads data files. On B) "Estimated Waveform Display Screen," the estimated lateral pressure Q, wheel load P, derailment coefficient Q / P, etc., according to the program are displayed. On C) "Target Value Exceed List Screen," the locations where the initially set target values ​​were exceeded are listed.

[0105] Thus, the evaluation software can output a list of vehicles exceeding the derailment coefficient guideline simply by inputting known data and settings, allowing users to more easily evaluate the running safety of railway vehicle 1.

[0106] [Differentiation] In the above embodiment, the cutoff frequency f of the low-pass filter LPF(1) and the low-pass filter LPF(2) c While examples of upper and lower limits for the bandwidth f of the bandpass filter (BPF) have been provided, it is not necessary to use the exemplified values; values ​​close to the exemplified values ​​may be used.

[0107] In the above embodiment, the evaluation software program was described as being stored in the storage unit 36 ​​within the evaluation unit 35, but it may also be stored in a storage unit on a server or in the cloud.

[0108] [Supplementary explanation of the embodiment] The embodiments described above are all preferred examples of the present invention. The numerical values, components, arrangement positions of components, and connection configurations shown in the embodiments above are examples only and are not intended to limit the present invention. Furthermore, the figures are not necessarily strictly illustrative.

[0109] Although embodiments of the present invention have been described above, these embodiments only represent a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

[0110] The series of processes described above can be executed by hardware or by software. When the series of processes are executed by software, the programs that make up the software are installed from a program storage medium on a computer that is built into dedicated hardware, or on a general-purpose computer that can perform various functions by installing various programs.

[0111] The programs executed by the computer may be programs that are processed chronologically in the order described herein, or they may be programs that are processed in parallel or at necessary times, such as when a call is made.

[0112] [Note] The contents described in some of the embodiments above can be understood, for example, as follows:

[0113] (1) Estimation of lateral pressure Q The method for evaluating the running safety of railway vehicle 1 includes the steps of detecting information about the bogie 10 of railway vehicle 1 while it is running, and the wheel axle yaw angular velocity Ψ of the bogie 10. W The steps include calculating the first lateral pressure component ΔQ1 relating to the frictional force acting between the inner track wheel 23 and the rail based on (dot) and velocity V, and the wheel axle left-right vibration acceleration y WBased on (two dots), the steps include calculating the second lateral pressure component ΔQ2 relating to the centrifugal force acting between the outer rail wheel 23 and the rail, and the wheel axle yaw angular velocity Ψ W The steps include calculating the third lateral pressure component ΔQ3 relating to the torsion of the air spring 25 between the bogie 10 and the car body 30 based on (dot) and speed V, and the wheel axle yaw angular velocity Ψ W The steps include: calculating the fourth lateral pressure component ΔQ4 acting between the outer rail wheel 23 and the rail based on (dot) and the slope C which has a positive linear relationship with the lateral pressure fluctuation component of the outer rail wheel 23; calculating the fifth lateral pressure component ΔQ5 with respect to the contact position x based on the contact position x between the outer rail wheel 23 and the rail and the outer rail wheel load P; estimating the lateral pressure Q acting between the outer rail wheel 23 and the rail by adding up all the lateral pressure components from the first lateral pressure component ΔQ1 to the fifth lateral pressure component ΔQ5; and the vertical displacement Z of the axle spring. 1L , Z 1R The method includes the steps of: estimating the wheel load P based on the lateral pressure Q; calculating the derailment coefficient Q / P by dividing the lateral pressure Q by the wheel load P; and evaluating the running safety of the railway vehicle 1 based on the derailment coefficient Q / P.

[0114] This allows for the evaluation of the running safety of railway vehicle 1 based on the derailment coefficient Q / P calculated by estimating the lateral pressure Q on a desk, without the need to conduct large-scale tests using the PQ axis. This reduces costs and improves versatility.

[0115] Furthermore, even without using the PQ axis, the wheelset yaw angular velocity Ψ W Since the fourth lateral pressure component ΔQ4 can be calculated based on the linearity between (dot) and the increase in lateral pressure, the estimation accuracy of fluctuating lateral pressure can be improved.

[0116] Furthermore, in the PQ axis, when the load position of the vertical load P of the wheel load shifts towards the flange side, the apparent lateral pressure Q increases. However, since this shift is calculated as a fifth lateral pressure component ΔQ5 based on the contact position x between the wheel 23 and the rail and the wheel load P, it is possible to obtain a highly accurate lateral pressure Q that takes this shift into account.

[0117] (2) Calculation of the variable component Q4 The step of calculating the fourth lateral pressure component ΔQ4 is performed by the wheel axle yaw angular velocity Ψ W The fourth transverse pressure component ΔQ4 may be calculated by multiplying the value obtained by applying a bandpass filter to (dot) by the slope C.

[0118] This results in the wheelset yaw angular velocity Ψ W Based on the correlation between (dot) and the increase in lateral pressure, the wheelset yaw angular velocity Ψ W After applying a bandpass filter to (dot), the stationary wheel load P st The fourth lateral pressure component ΔQ4 is calculated by multiplying it by the slope C, which has a linear relationship with it.

[0119] Therefore, the measured wheelset yaw angular velocity Ψ W By applying a bandpass filter to the (dot) as a yaw rate sensor, only the appropriate frequency components can be extracted, further improving the estimation accuracy of the fourth lateral pressure component ΔQ4.

[0120] (3) Calculation of the apparent lateral pressure component Q5 based on the wheel contact position The step of calculating the fifth lateral pressure component ΔQ5 is performed by the wheel axle yaw angular velocity Ψ W The curvature of the track may be calculated based on the (dot) and velocity V, the current contact position x may be calculated based on the relationship between curvature and contact position x which has been determined in advance by simulation, and the fifth lateral pressure component ΔQ5 with respect to the contact position x may be calculated based on the contact position x and the wheel load P on the outer rail side.

[0121] This allows us to determine the relationship between curvature and contact position x through prior simulation, and the wheel axle yaw angular velocity Ψ W Since the contact position x is determined based on the curvature calculated from the (dot) and velocity V, the estimation accuracy of the fifth lateral pressure component ΔQ5 can be improved.

[0122] (4) Estimation of wheel load using estimated lateral pressure Q The step of estimating the wheel load P is the vertical displacement Z of the axle spring. 1L , Z 1R The vertical stiffness of the axle spring k 1ZMultiply to obtain the change amount F of the vertical force of the axle spring from the stationary state of the carriage 10 zl 、F zR Calculate, and the wheel load P may be estimated based on the change amount F of the vertical force of the axle spring zl 、F zR and the estimated lateral pressure Q

[0123] Thus, without directly measuring the wheel load P, using the estimated lateral pressure Q, the vertical displacement Z of the axle spring 1L 、Z 1R and the vertical stiffness k of the axle spring 1Z it is possible to estimate the wheel load P without using some of the vehicle specifications. Therefore, the calculation becomes simple and the calculation load can be reduced

[0124] (5) Coefficient of friction during dry conditions The step of calculating the first lateral pressure component ΔQ1 may calculate the frictional force acting between the wheel on the inner rail side and the rail based on the coefficient of friction of the rail on the inner rail side during dry conditions

[0125] Thus, since the frictional force is calculated using the coefficient of friction between the wheel and the rail when the rail on the inner rail side is dry, such as on sunny days when the coefficient of friction is large, the first lateral pressure component ΔQ1 can be calculated under more severe conditions, and a more appropriate estimation can be made as a safety evaluation

[0126] (6) Inclination setting The step of calculating the fourth lateral pressure component may set a larger inclination as the mass of the car body of the railway vehicle is larger<{ Thus, since the inclination can be set in consideration of the car body mass that affects the inclination, the fourth lateral pressure component can be calculated more accurately

[0127] [[ID=|40]](6) Device (corresponding to claim 1 The running safety evaluation device 100 of the railway vehicle 1 includes a detection unit that detects information on the carriage 10 in the running railway vehicle 1, and the yaw angular velocity Ψ of the wheel axle of the carriage 10 W(Dot) and based on the speed V, a first calculation unit that calculates a first lateral pressure component ΔQ1 related to the frictional force acting between the wheel 23 on the inner rail side and the rail, and the axle lateral vibration acceleration y W (Double dot) and based on W , a second calculation unit that calculates a second lateral pressure component ΔQ2 related to the centrifugal force acting between the wheel 23 on the outer rail side and the rail, and the axle yaw angular velocity Ψ W (Dot) and based on the speed V, a third calculation unit that calculates a third lateral pressure component ΔQ3 related to the torsion of the air spring 25 between the bogie 10 and the car body 30, and the axle yaw angular velocity Ψ W (Dot) and based on the slope C that has a positive linear relationship with the lateral pressure fluctuation component of the wheel 23 on the outer rail side, a fourth calculation unit that calculates a fourth lateral pressure component ΔQ4 acting between the wheel 23 on the outer rail side and the rail, and based on the contact position x between the wheel 23 on the outer rail side and the rail, and the wheel load P on the outer rail side, a fifth calculation unit that calculates a fifth lateral pressure component ΔQ5 related to the contact position x, and a lateral pressure estimation unit 34a that adds all of the first lateral pressure component ΔQ1 to the fifth lateral pressure component ΔQ5 to estimate the lateral pressure Q acting between the wheel 23 on the outer rail side and the rail, the axle spring vertical displacement Z 1L 、Z 1R and based on Z and the lateral pressure Q, a wheel load estimation unit 34b that estimates the wheel load P, a calculation unit that divides the lateral pressure Q by the wheel load P to calculate the derailment coefficient Q / P, and an evaluation unit 35 that evaluates the running safety of the railway vehicle based on the derailment coefficient Q / P.

[0128] Thereby, without performing a large-scale test using the PQ axis, the running safety of the railway vehicle 1 can be evaluated based on the derailment coefficient Q / P estimated and calculated for the lateral pressure Q on the ground, so that the cost can be reduced and the versatility can be improved.

[0129] Also, even without using the PQ axis, based on the linearity between the axle yaw angular velocity Ψ W (Dot) and the lateral pressure increase amount, the fourth lateral pressure component ΔQ4 can be calculated, so that the estimation accuracy of the fluctuating lateral pressure can be improved.

[0130] Furthermore, in the PQ axis, when the load position of the vertical load P of the wheel load shifts towards the flange side, the apparent lateral pressure Q increases. However, since this shift is calculated as a fifth lateral pressure component ΔQ5 based on the contact position x between the wheel 23 and the rail and the wheel load P, it is possible to obtain a highly accurate lateral pressure Q that takes this shift into account.

[0131] (7) Program (corresponding to claim 1) The railway vehicle running safety evaluation program includes the steps of detecting information about the bogie 10 of the railway vehicle while it is running, and the wheel axle yaw angular velocity Ψ of the bogie 10. W The steps include calculating the first lateral pressure component ΔQ1 relating to the frictional force acting between the inner track wheel 23 and the rail based on (dot) and velocity V, and the wheel axle left-right vibration acceleration y W Based on (two dots), the steps include calculating the second lateral pressure component ΔQ2 relating to the centrifugal force acting between the outer rail wheel 23 and the rail, and the wheel axle yaw angular velocity Ψ W The steps include calculating the third lateral pressure component ΔQ3 relating to the torsion of the air spring 25 between the bogie 10 and the car body 30 based on (dot) and speed V, and the wheel axle yaw angular velocity Ψ W The steps include: calculating the fourth lateral pressure component ΔQ4 acting between the outer rail wheel 23 and the rail based on (dot) and the slope C which has a positive linear relationship with the lateral pressure fluctuation component of the outer rail wheel 23; calculating the fifth lateral pressure component ΔQ5 with respect to the contact position x based on the contact position x between the outer rail wheel 23 and the rail and the outer rail wheel load P; estimating the lateral pressure Q acting between the outer rail wheel 23 and the rail by adding up all the lateral pressure components from the first lateral pressure component ΔQ1 to the fifth lateral pressure component ΔQ5; and the vertical displacement Z of the axle spring. 1L , Z 1R The method includes the steps of: estimating the wheel load P based on the lateral pressure Q; calculating the derailment coefficient Q / P by dividing the lateral pressure Q by the wheel load P; and evaluating the running safety of the railway vehicle based on the derailment coefficient Q / P.

[0132] This allows for the evaluation of the running safety of railway vehicle 1 based on the derailment coefficient Q / P calculated by estimating the lateral pressure Q on a desk, without the need to conduct large-scale tests using the PQ axis. This reduces costs and improves versatility.

[0133] Furthermore, even without using the PQ axis, the wheelset yaw angular velocity Ψ W Since the fourth lateral pressure component ΔQ4 can be calculated based on the linearity between (dot) and the increase in lateral pressure, the estimation accuracy of fluctuating lateral pressure can be improved.

[0134] Furthermore, in the PQ axis, when the load position of the vertical load P of the wheel load shifts towards the flange side, the apparent lateral pressure Q increases. However, since this shift is calculated as a fifth lateral pressure component ΔQ5 based on the contact position x between the wheel 23 and the rail and the wheel load P, it is possible to obtain a highly accurate lateral pressure Q that takes this shift into account. [Explanation of Symbols]

[0135] 1. Railway vehicles 10 carts 16 Axle spring 23 wheels 25 Air spring 30 car bodies 34 Lateral force / wheel load estimation section (1st to 5th calculation section, calculation section) 34a Lateral pressure estimation unit 34b Wheel load estimation section 35 Evaluation Department F zl F zR Change in the vertical force of the axle spring k 1Z Axle spring vertical stiffness P Wheel load Q Lateral pressure Q / P derailment coefficient V speed x Contact position Z1, Z 1R Axle spring vertical displacement Ψ W (Dot) Wheel and axle yaw angular velocity y W (Two dots) Wheel shaft left and right vibration acceleration

Claims

1. A step of detecting information about the bogie of a moving railway vehicle, The steps include: calculating a first lateral pressure component relating to the frictional force acting between the inner rail wheel and the rail based on the wheel axle yaw angular velocity and speed of the bogie; The steps include: calculating the second lateral pressure component related to the centrifugal force acting between the outer wheel and the rail based on the left-right vibration acceleration of the wheel axle; The steps include: calculating a third lateral pressure component relating to the torsion of the air spring between the bogie and the car body based on the wheelset yaw angular velocity and the speed; A step of calculating a fourth lateral pressure component acting between the outer rail wheel and the rail based on the wheel axle yaw angular velocity and the slope which has a positive linear relationship with the lateral pressure fluctuation component of the outer rail wheel, A step of calculating a fifth lateral pressure component with respect to the contact position based on the contact position between the wheel on the outer rail and the rail, and the wheel load on the outer rail, A step of estimating the lateral pressure acting between the wheel on the outer rail and the rail by adding up all of the first to fifth lateral pressure components, A step of estimating the wheel load based on the vertical displacement of the axle spring and the lateral pressure, The steps include: calculating the derailment coefficient by dividing the aforementioned lateral pressure by the aforementioned wheel load; A step of evaluating the running safety of the railway vehicle based on the derailment coefficient, A method for evaluating the running safety of a railway vehicle, characterized by including [a specific element].

2. A method for evaluating the running safety of a railway vehicle according to claim 1, The step of calculating the fourth lateral pressure component involves multiplying the value obtained by applying a bandpass filter to the wheel axle yaw angular velocity by the slope to calculate the fourth lateral pressure component. A method for evaluating the running safety of railway vehicles, characterized by the features described herein.

3. A method for evaluating the running safety of a railway vehicle according to claim 1, The step of calculating the fifth lateral pressure component involves calculating the curvature of the track based on the wheelset yaw angular velocity and the speed, calculating the current contact position based on the relationship between the curvature and the contact position which was previously determined by simulation, and calculating the fifth lateral pressure component with respect to the contact position based on the contact position and the wheel load on the outer rail side. A method for evaluating the running safety of railway vehicles, characterized by the features described herein.

4. A method for evaluating the running safety of a railway vehicle according to claim 1, The step of estimating the wheel load involves multiplying the vertical displacement of the axle spring by the vertical stiffness of the axle spring to calculate the change in the vertical force of the axle spring from the stationary state of the bogie, and then estimating the wheel load based on the change in the vertical force of the axle spring and the estimated lateral pressure. A method for evaluating the running safety of railway vehicles, characterized by the features described herein.

5. A method for evaluating the running safety of a railway vehicle according to claim 1, The step of calculating the first lateral pressure component involves calculating the frictional force acting between the wheel on the inner rail side and the rail, based on the coefficient of friction of the inner rail side when the rail is dry. A method for evaluating the running safety of railway vehicles, characterized by the features described herein.

6. A method for evaluating the running safety of a railway vehicle according to claim 1, The step of calculating the fourth lateral pressure component involves setting the inclination to be larger the larger the mass of the railway vehicle body. A method for evaluating the running safety of railway vehicles, characterized by the features described herein.

7. A detection unit that detects information about the bogie of a moving railway vehicle, A first calculation unit calculates a first lateral pressure component relating to the frictional force acting between the inner rail wheel and the rail based on the wheel axle yaw angular velocity and speed of the bogie, A second calculation unit calculates a second lateral pressure component related to the centrifugal force acting between the outer wheel and the rail based on the left-right vibration acceleration of the wheel axle, A third calculation unit calculates a third lateral pressure component relating to the torsion of the air spring between the bogie and the car body based on the wheelset yaw angular velocity and the speed, A fourth calculation unit calculates a fourth lateral pressure component acting between the outer rail-side wheel and the rail based on the wheel axle yaw angular velocity and the slope which has a positive linear relationship with the lateral pressure fluctuation component of the wheel, A fifth calculation unit calculates a fifth lateral pressure component related to the contact position based on the contact position between the wheel on the outer rail and the rail, and the wheel load on the outer rail. A lateral pressure estimation unit that estimates the lateral pressure acting between the wheel and the rail by adding up all of the aforementioned lateral pressure components from the first to the fifth lateral pressure components, A wheel load estimation unit that estimates the wheel load based on the vertical displacement of the axle spring and the lateral pressure, A calculation unit that calculates the derailment coefficient by dividing the aforementioned lateral pressure by the aforementioned wheel load, An evaluation unit that evaluates the safety of the railway vehicle based on the derailment coefficient, A railway vehicle running safety evaluation device characterized by comprising the following:

8. A step of detecting information about the bogie of a moving railway vehicle, The steps include: calculating a first lateral pressure component relating to the frictional force acting between the inner rail wheel and the rail based on the wheel axle yaw angular velocity and speed of the bogie; The steps include: calculating the second lateral pressure component related to the centrifugal force acting between the outer wheel and the rail based on the left-right vibration acceleration of the wheel axle; The steps include: calculating a third lateral pressure component relating to the torsion of the air spring between the bogie and the car body based on the wheelset yaw angular velocity and the speed; A step of calculating a fourth lateral pressure component acting between the outer rail wheel and the rail based on the wheel axle yaw angular velocity and the slope which has a positive linear relationship with the lateral pressure fluctuation component of the wheel, A step of calculating a fifth lateral pressure component with respect to the contact position based on the contact position between the wheel on the outer rail and the rail, and the wheel load on the outer rail, A step of estimating the lateral pressure acting between the wheel and the rail by adding up all of the aforementioned lateral pressure components from the first to the fifth, A step of estimating the wheel load based on the vertical displacement of the axle spring and the lateral pressure, The steps include: calculating the derailment coefficient by dividing the aforementioned lateral pressure by the aforementioned wheel load; A step of evaluating the running safety of the railway vehicle based on the derailment coefficient, A railway vehicle running safety evaluation program characterized by including [a specific feature].

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