JP2002178797A - Wave motion propagation speed measuring method of trolley wire, and tension measuring method of trolley wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of measuring wave motion propagation speed or tension of a trolley wire based on contact force variation of a pantograph measured on a running vehicle. SOLUTION: Regarding to the contact force variation of trolley line- pantograph system, a contact force variation frequency fv generated by the fact that exciting wave motion excited as a result of periodicity of the trolley line propagates through the trolley line, reflects at a discontinuous point of the trolley line, and comes into the pantograph again is represented by fv= (1+β)/(1-β)}×fL. By normalizing the frequency represented by the equation by a train speed, KV= (1+β)/(1-β)}×KL is derived. It is recognized that the wave number KV varies with a ratio β of the train speed and the wave motion propagation speed of the trolley wire. Therefore, when the wave number KV of a dynamic component included in the contact force variation is accurately provided, and simultaneously train speed v is also obtained, the wave motion propagation speed of the trolley wire can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the contact force acting between a trolley wire and a pantograph on a moving vehicle and measuring the wave propagation velocity of the trolley wire based on the measured value. .

[0002]

2. Description of the Related Art In a current electric railway for business use, a system for transmitting electric power from a trolley wire to a vehicle body via a pantograph is generally used. The contact force between the trolley wire and the boat body of the pantograph fluctuates in accordance with the height of the trolley wire, vibration of the vehicle / pantograph, and the like.
If the fluctuation of the contact force is too large, there is a possibility that the pantograph boat may be separated from the trolley wire. If the disconnection frequently occurs, a spark is generated between the trolley wire and the boat body of the pantograph, and abrasion of the sliding plate proceeds, which is a problem. Even in the case where no derailment occurs, the fluctuation of the contact force of the pantograph should be as small as possible.

[0003] Therefore, there is a demand that the contact force between the trolley wire and the pantograph while the train is running is measured, and the obtained measurement result is used as a reference for measures to suppress the disconnection. Alternatively, it is considered that such a contact force measurement technique is used not only as a measure for suppressing the disconnection, but also as one of methods for evaluating the power collection performance of the overhead wire-pantograph system and for diagnosing the equipment of the train line. .

As a technique for measuring the contact force of such a pantograph, for example, Japanese Patent Application No. 11-191611 and Japanese Patent Application No.
No. 000-122299. The method of measuring the contact force of a pantograph in Japanese Patent Application No. 11-191611 is to determine the inertial force of a boat body of a pantograph in consideration of elastic deformation between two longitudinal sections including a sliding plate of the boat body, and this inertial force is obtained. Is subtracted from the separately determined force on the hull to determine the vertical contact force of the hull.

The method of measuring the contact force of a pantograph disclosed in Japanese Patent Application No. 2000-122299 is based on a method in which the inertial force of a boat body of a pantograph is determined by measuring the torsional moment in two longitudinal sections including a sliding plate of the boat body and the action between these vertical sections. The torsional moment of the hull is determined based on the rotational inertia of the hull, and the longitudinal contact force acting between the trolley wire and the hull is also determined based on the torsional moment. In this specification, the term “hull” is generally used in a broad sense including a sliding plate.

With these contact force measurement techniques, it has become possible to more accurately determine the contact force (vertical direction and front-back direction) between the trolley wire and the pantograph hull. By the way, recently, a technique for measuring a wave propagation velocity of a trolley wire, which is an important parameter for determining a dynamic behavior of an overhead wire-pantograph system, is required.

As a method of measuring the wave propagation velocity, there have been proposed many methods of measuring the wave propagation velocity by directly attaching a sensor or the like to the overhead wire side (for example, Japanese Patent Application Laid-Open No. 10-176968). . However,
A method for measuring the wave propagation velocity of the trolley wire based on the information on the pantograph side is not currently provided. The present invention
In view of such circumstances, it is an object of the present invention to provide a method capable of measuring a wave propagation velocity or a tension of a trolley wire based on a variation in a contact force of a pantograph measured on a running vehicle. .

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a method for measuring the wave propagation velocity of a trolley wire according to the present invention is applied to an electric railway which feeds a train from a trolley wire via a pantograph. A method for measuring the wave propagation velocity of a trolley wire; measuring a contact force variation acting between the trolley wire and the pantograph while running the train, decomposing the contact force variation into frequency components to obtain a dominant component. Extracting a component (trolley wire wave component) related to the dynamic wave of the trolley wire from the dominant component,
A wave propagation speed of the trolley wire is obtained based on the trolley wire wave component.

[0009] The wave propagation velocity of the trolley wire is an important parameter that determines the dynamic behavior of the overhead wire-pantograph system. ADVANTAGE OF THE INVENTION According to this invention, the wave propagation speed of a trolley wire can be measured by the information from a pantograph side on the running train based on the contact force fluctuation which acts between a trolley wire and a pantograph. This eliminates the need for the trolley wire facility diagnosis work conventionally performed on the ground, and furthermore, a large number of drum sections (one drum = one unit of the trolley wire (about 1.5 km) at a time by a running train. )) Can be measured, so that the efficiency of trolley wire equipment diagnosis and maintenance work can be significantly improved. As a technique for measuring the contact force fluctuation in the present invention, Japanese Patent Application No. 11-191611 and Japanese Patent Application
The one disclosed in 00-122299 can be used.

In the method for measuring the wave propagation speed of a trolley wire according to the present invention, the wave propagation speed of the trolley wire can be calculated by the following equation; the wave number representing the spatial periodic structure of the trolley wire is k _L , The wave number when the frequency of the wave component generated by the structure is made dimensionless at the train speed v is k
_v , where β is a dimensionless speed obtained by normalizing the train speed with the wave propagation speed of the trolley wire, k _v = {(1 + β) / (1-β)} × k _L.

[0011] The contact force fluctuation of the overhead wire-pantograph system includes:
There are two factors described in the following (1) and (2): (1) Periodicity of overhead wire (dip between hangers of trolley wire, etc.)
Due to (2) A wave generated when a wave excited as a result of (1) propagates through a trolley wire, is reflected at a discontinuous point of an overhead wire such as a hanger, and reenters a pantograph. here,
The frequency f _L of the contact force fluctuation in (1) is proportional to the train speed,
Assuming that the wave propagation velocity of the trolley wire is c, (1 ′) f _L = β × c / L. On the other hand, the frequency f of the contact force variation in (2)
_v is expressed as (2 ′) f _v = {(1 + β) / (1-β)} × f _L in consideration of frequency modulation by the Doppler effect. Here, L is a representative length representing the periodicity of the overhead line.

Therefore, when the frequencies represented by the equations (1 ') and (2') are normalized by the train speed, the components represented by the equation (1 ') (that is, proportional to the representative length L of the space) wavenumber k _L a to component), "constant value) k _L = 1 / _L. Meanwhile, (for wave number k _v of the wave component represented by 2 ') below, (2" (1) k _v = {(1 + β) / (1-β)} × k _L , and it can be seen that the wave number k _v changes with the train speed v. Therefore, if the wave number k _{v of the} wave component included in the contact force fluctuation can be accurately grasped and the train speed v can be obtained at the same time, the wave propagation speed of the trolley wire can be obtained by equation (2 ″).

In the method for measuring the wave propagation velocity of a trolley wire according to the present invention, it is preferable that the dominant component is extracted based on a hanger interval of the trolley wire. Among the components described in the above (2), a contact wave caused by a dynamic wave generated due to a dip between hangers of a trolley wire propagating in front of a train, reflected by a hanger or the like, and again incident on the pantograph from the front. The contribution of fluctuation is large. Accordingly, by extracting basis excellence component hanger spacing, you can capture wavenumber k _v more accurately, which makes it possible to obtain a more accurate wave propagation velocity. The hanger interval is, for example, 5 m, and the wave number k _{L in} this case is 1/5 = 0.2 from the equation (1 ″).

A method for measuring the tension of a trolley wire according to the present invention is a method for measuring the tension of a trolley wire in an electric railway that supplies power to a train from a trolley wire via a pantograph. The contact force fluctuation acting during the measurement is measured, and the contact force fluctuation is decomposed into frequency components to extract a dominant component. From the dominant component, a component related to the dynamic wave of the trolley wire (a trolley wire wave component) Is extracted, the wave propagation velocity of the trolley wire is obtained based on the trolley wire wave component, and the thickness of the trolley wire is further measured by a laser-type wear measuring device or the like. The thickness of the trolley wire and the wave propagation velocity are It is characterized by measuring the tension of the trolley wire.

As for the method of measuring the thickness of a trolley wire from a traveling vehicle, many methods including a laser-type wear measuring device have already been put to practical use. On the other hand, the wave propagation velocity of the trolley wire is (Trolley wire tension (N) ÷ trolley wire linear density (kg /
m)) It can be obtained by ^1/2 . Therefore, by determining the thickness of the trolley wire and the wave propagation velocity, the tension of the trolley wire can also be determined.

Hereinafter, description will be made with reference to the drawings. In addition,
In the following description, the longitudinal direction of the rail (the traveling direction of the vehicle) is the front-rear direction, the direction perpendicular to the rail longitudinal direction on the track surface is the left-right direction, and the direction perpendicular to the track surface is the same as in the ordinary railway vehicle technology. The direction is called a vertical direction. Further, a specific numerical example is a general numerical value of the current JR Shinkansen.

First, an overhead line-pantograph system of an electric railway will be described with reference to FIGS. FIG. 4 is a perspective view showing details of the boat body of the pantograph in this embodiment. Although not shown in FIG. 4, the boat body is attached to the ceiling of the train by rods, boat supports, restoring springs, link-shaped frameworks, and the like. FIG. 5 is a schematic diagram showing an overhead wire structure in the present embodiment.

The trolley wire 1 is a copper wire having a diameter of about 15 mm. A voltage of AC 25 kV is applied to the trolley wire 1. As shown in FIG. 5, the trolley wire 1 is suspended by a suspension wire 5 via a hanger 3 at intervals of about 5 m. The suspension wire 5 is supported by a wire pillar 7 at an interval of about 50 m. The length per trolley wire unit (one drum section) is about 1.5 km.

As shown in FIG. 4, the boat body 12 in this example is
It extends along the left-right direction. In many cases, two boats 12 (12A and 12B) are provided one by one at a distance from each other in the front-rear direction, but there are also boats that are configured with only one boat. The boat body 12 in this example has a width of 40 mm, a length of 1.2 m,
It is a hollow box-shaped member weighing 3.5 kg. The boat body 12 is made of an aluminum alloy. The force with which the hull 12 is pressed against the trolley wire 1 when stopped (static push-up force) is 50 to 70N.

A sliding plate 14 is mounted on the upper surface of the boat body 12. The sliding plate 14 is made of an iron-based or copper-based sintered alloy or a carbon-based material. This sliding plate 14
Is often divided into four parts as shown in FIG. Of these, the central two are the main sliders, and the two at the left and right are auxiliary sliders. Mainly, the main slide plate directly contacts the trolley wire 1. The sliding plate 14 is worn out with time due to the contact with the trolley wire 1 and is therefore periodically replaced.

A two-axis strain gauge 31 is attached to the boat body 12. As the two-axis strain gauge 31, a non-inductive gauge is used in order to prevent noise from being induced by the current collection current. The shearing force acting on the boat body 12 can be obtained from the shear strain of the cross section of the boat body 12 measured by the biaxial strain gauge 31. In this example, the biaxial strain gauge 31
Are attached on the front side and the rear side of the boat body 12, respectively. Therefore, a total of four biaxial strain gauges 31 are provided for one boat body 12. The left and right strain gauges 31 are attached to positions including the main slide plate of the slide plate 14 (specifically, positions where bolts for fixing the auxiliary plate of the slide plate 14 to the boat body 12 are screwed). .

Further, one accelerometer 35 per one hull is attached to the center lower surface of the hull 12. The frequency that can be measured by the accelerometer 35 is about 40 Hz or less. However, by installing a plurality of accelerometers as needed, measurement in a higher frequency range is possible. The inertial force of the hull 12 can be obtained from the acceleration at the center of the hull 12 measured by the accelerometer 35.

Each of the two-axis strain gauges 31 and the accelerometer 35 of the boat body 12 are connected to an arithmetic unit (not shown). This arithmetic unit receives signals from the two-axis strain gauge 31 and the accelerometer 35 and calculates the contact force between the boat body 12 and the trolley wire 1. The principle of measuring this contact force is described in Japanese Patent Application
This is the same as that disclosed in Japanese Patent Application No. 1916111 and Japanese Patent Application No. 2000-122299.

Next, a specific example of the result of measuring the wave propagation velocity of the trolley wire based on the contact force measurement will be described with reference to FIG.
This will be described with reference to FIG. FIG. 1 is a flowchart illustrating an example of a method for measuring a wave propagation velocity of a trolley wire according to the present invention. As shown in FIG. 1, in measuring the wave propagation velocity of the trolley wire, first, in step S1, the contact force fluctuation between the hull 12 and the trolley wire 1 on the running vehicle is measured. Here, the contact force fluctuation of the overhead wire-pantograph system has two factors described in the following (1) and (2);
Due to (2) A wave generated when a wave excited as a result of (1) propagates through a trolley wire, is reflected at a discontinuous point of an overhead wire such as a hanger, and reenters a pantograph.

The frequency f _L of the contact force fluctuation in the above (1) is proportional to the train speed, and if the wave propagation speed of the trolley wire is c, it is expressed as (1 ′) f _L = β × c / L. Frequency f _v generated by the wave generated by the contact force fluctuation entering again from the front of the pantograph
Is expressed as (2 ′) f _v = {(1 + β) / (1-β)} × f _L

After step S1, a short-time Fourier analysis of the contact force fluctuation is performed in step S2. Next, in step S3, a prominent component is extracted from the result of the short-time Fourier analysis. Further, in step S4,
A frequency f _v corresponding to a trolley wire wave component is extracted from the dominant component.

Then, in step S5, the frequency f represented by the above equations (1 ') and (2') is normalized by the train speed v. This is to obtain the wave number k (unit 1 / m) by dividing the frequency f (unit Hz) by the train speed v,
That is, it corresponds to conversion to k = f / v. Then, the wave number k _L of the component represented by the equation (1 ′) becomes a constant value of (1 ″) k _L = 1 / L. In this embodiment, the representative length L of the space is determined by the hanger of the trolley wire. The interval was 5 m, in this case (1 ″)
From the equation, the wave number k _L = １ ／ = 0.2. on the other hand,
The wave number k _v of the wave component represented by the equation (2 ′) is (2 ″) k _v = {(1 + β) / (1−β)} × k _L. After step S5, in step S6 The wave propagation velocity of the trolley wire is calculated based on the above equation (2 ″).

FIG. 2 shows the values of f _v and k _v in the equations (2 ′) and (2 ″) when the representative length L of the space is 5 m, respectively, for the heavy pound overhead line and the CS simple overhead line. Fig. 2 is a graph showing the result of calculation for Fig. 2.
, The horizontal axis represents train speed (unit km / h), the left vertical axis represents contact force variation frequency (unit Hz), and the right vertical axis represents contact force variation wavenumber (unit 1 / m). In the graph in the figure, the thin solid line and the dotted line represent the contact force fluctuation frequency and the contact force fluctuation wave number of the heavy beacon overhead line, respectively, and the thick solid line and the dotted line represent the contact force fluctuation frequency and the contact force fluctuation wave number of the CS simple overhead line, respectively.

The heavy beacon overhead wire is 170 mm ²
Copper trolley wire (tensile 14.7kN, wire density 1.51k
g / m). CS simple overhead line is 11
A 0 mm ² copper-clad steel trolley wire (19.6 kN tension, 0.94 kg / m linear density) is used. As can be seen from FIG. 2, all the graphs are rising to the right. From this, it can be seen that the contact force variation frequency and the contact force variation wave number take a higher value as the train speed increases, and that it is strongly affected by the train speed. Therefore, the wave number k _{v of the} wave component included in the contact force fluctuation is accurately captured,
If the train speed v can be obtained at the same time, it can be said that the wave propagation speed of the trolley wire can be obtained by the equation (2 ″).

FIG. 3A is a graph showing the result of short-time Fourier analysis of the waveform of the contact force fluctuation measured in the CS simple overhead line section, and FIG.
It is a graph showing. In FIG. 3A, the horizontal axis represents time (unit: s), and the vertical axis represents wavenumber (unit: 1 / m). In FIG. 3 (A), the dominant component of the contact force variation is shaded. From FIG. 3 (A), it can be seen that a large contact force variation occurs at a place with a wave number of 0.2 corresponding to a hanger interval of 5 m. Also, above the wave number 0.2,
A component whose wave number changes with speed is also recognized. This is considered to indicate the contact force fluctuation component generated by the trolley wire wave excited by the contact force fluctuation of the hanger interval cycle.

Therefore, assuming that the trolley wire wave propagation velocity c in the CS simple overhead line section is constant, the value of the wave number k _v calculated by the equation (2 ″) matches the actually measured wave component. When the trolley wire wave propagation velocity c was obtained as described above, a value of c = 480 km / h was obtained.
The graph shown by the solid line in (A) is the calculated value of the wave number when c = 480 km / h. The characteristics indicated by the solid line and the actual measurement result (the hatched area near the solid line in FIG. 3A) agree well, and it can be said that the method of estimating the trolley wire wave propagation velocity shown here is appropriate.

The thickness of the trolley wire can be easily measured by a laser type wear measuring device or the like. The wave propagation velocity of the trolley wire is (Trolley wire tension (N) ÷ trolley wire linear density (kg /
m)) It can be obtained by ^1/2 . Therefore, by determining the thickness of the trolley wire and the wave propagation velocity, the tension of the trolley wire can also be determined.

As described above, according to the present invention, the wave propagation speed of the trolley wire and the trolley wire based on the information from the pantograph side on the running train on the basis of the contact force fluctuation acting between the trolley wire and the pantograph. Can be measured. This eliminates the need for the trolley wire facility diagnosis work conventionally performed on the ground, and furthermore, a large number of drum sections (one drum = one unit of the trolley wire (about 1.5 km) at a time by a running train. )) Can be measured,
The efficiency of trolley wire equipment diagnosis and maintenance work can be significantly improved.

[0034]

As is apparent from the above description, according to the present invention, the wave propagation speed or tension of the trolley wire can be measured based on the fluctuation of the contact force of the pantograph measured on the running vehicle.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an example of a method of measuring a wave propagation velocity of a trolley wire according to the present invention.

FIG. 2 shows f _v , when the representative length L of the space is 5 m.
The value of k _v, which is a graph showing the result of calculation for each heavy compounds overhead line and CS simple overhead wires.

FIG. 3A is a graph showing a result of a short-time Fourier analysis of a waveform of a contact force fluctuation measured in a CS simple overhead line section, and FIG. 3B is a graph showing a train speed v. is there.

FIG. 4 is a perspective view showing details of a boat body of the pantograph described in the present embodiment.

FIG. 5 is a schematic view showing an overhead wire structure in the present embodiment.

[Explanation of symbols]

Reference Signs List 1 trolley wire 3 hanger 5 suspension wire 7 overhead wire pole 12 (12A, 12B) hull 14 sliding plate 31 two-axis strain gauge 35 accelerometer

Continuation of the front page (72) Inventor Takayuki Usuda 2-8-8 Hikaricho, Kokubunji-shi, Tokyo F-term in the Railway Technical Research Institute 2F051 AA01 AB04 CA00 2G064 AA14 AB05 CC29 CC41

Claims (4)

[Claims] 1. A method for measuring a wave propagation velocity of a trolley wire in an electric railway which supplies a train from a trolley wire via a pantograph; a contact force acting between the trolley wire and the pantograph while running the train. The variation is measured, the contact force variation is decomposed into frequency components to extract a dominant component, and a component related to the dynamic wave of the trolley wire (a trolley wire wave component) is extracted from the dominant component. A method for measuring a wave propagation velocity of a trolley wire, wherein a wave propagation velocity of the trolley wire is obtained based on a wave component. Wave number k _L representing the spatial periodic structure of the trolley line; wherein said contact wire wave propagation velocity wave propagation velocity measuring method of the trolley wire of claim 1, wherein the calculating the following formula The wave number when the frequency of the wave component generated by this spatial periodic structure is made dimensionless at the train speed v is k
_v , where β is a dimensionless speed obtained by normalizing the train speed with the wave propagation speed of the trolley wire, k _v = {(1 + β) / (1-β)} × k _L. 3. The method of measuring a wave propagation velocity of a trolley wire according to claim 1, wherein the dominant component is extracted based on a hanger interval of the trolley wire. 4. A method for measuring the tension of a trolley wire in an electric railway which feeds a train from a trolley wire via a pantograph, wherein a contact force variation acting between the trolley wire and the pantograph is measured while the train is running. Measuring the contact force fluctuation into frequency components to extract a dominant component, extracting a component related to the dynamic wave of the trolley wire (a trolley wire wave component) from the dominant component, Determining the wave propagation velocity of the trolley wire based on the following formula, further measuring the thickness of the trolley wire with a laser sensor or the like, and measuring the tension of the trolley wire from the thickness of the trolley wire and the wave propagation velocity. A method for measuring the tension of a trolley wire.