JPS6175054A - Measuring device for distance between train - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a distance measuring device for measuring the distance from a power transmission end set on a track circuit to a short-circuit point of the track circuit caused by a train.

Prior Art For example, as shown in Fig. 3, in a train AI traveling in the direction of arrow (a) on track l, the train distance (intersection) between it and the preceding train B1 is 1+cross 2
), and it is necessary to be able to control the speed Vd according to the train distance (text 1+-9, 2). Conventionally, as a means of obtaining distance information, the current that flows due to a short circuit in a track circuit caused by a train axle changes depending on the distance, which is used to operate a relay and issue a warning when a train approaches beyond the allowable distance. However, the track circuit current increases on rainy days and decreases on sunny days, so it is easily influenced by the climate, so the distance at which a warning is issued is fixed. However, the problem was that the operation became unstable.

As a technique to eliminate these conventional drawbacks, a train distance measuring device has been proposed that focuses on the fact that the short-circuit impedance when a track circuit is shorted by a train axle changes in accordance with the train distance. FIG. 4 is an electrical equivalent circuit diagram of the main part of this train distance measuring device, in which an alternating current of an appropriate frequency f is transmitted to the track circuit 3.4 using the transmitting device 2 installed near the boundary of the blocked section. While passing current, this transmitting device 2
The receiver coil 5 is arranged at a position slightly away from the installation position of the receiver.

In the above train distance measuring device, when the current flowing through the track circuit 3.4 is 1 and the gauge voltage is vl, the short circuit impedance Zl when looking from the transmitting device 2 to the train Al side is Z1 = V1/11. As shown in FIG. 5, the short-circuit impedance Z1 is approximately proportional to the distance from the blocking boundary where the transmitting device 2 and the receiving coil 5 are to the train AX, so the distance #A can be known from the short-circuit impedance ZL. . In addition, the fifth
The figure shows the frequency of the AC power applied to the transmitter 2 at 3KH.
The characteristics when z is shown.

Disadvantages of the Prior Art However, the train distance measuring device shown in Fig. 4 requires the installation of the receiving coil 5 within the track bed, making the installation work cumbersome, lacking in practicality, and increasing costs. However, there are drawbacks such as the receiving coil 5 becoming an obstacle to track maintenance work.Objective of the Present InventionThe present invention solves the above-mentioned conventional problems and eliminates the need to provide a receiving coil within the track bed. It is easy to implement, highly practical and economical, and does not interfere with track maintenance work.
The purpose of the present invention is to provide a train distance measuring device that can be applied to non-insulated track circuits and has high fail-safe properties.

Structure of the Present Invention In order to achieve the above object, the present invention provides a device for measuring the distance from a certain point set on a track circuit to a track circuit short-circuit point caused by a train. A means for detecting a voltage difference between the voltage and a gauge voltage at a point set near the power transmission end is provided, and the distance is measured using a voltage signal proportional to the voltage difference obtained by the detection means. It is characterized by

Embodiment FIG. 1 shows an electric circuit of a main part of a train distance measuring device according to the present invention. In FIG. 0, the same reference numerals as in FIG. 4 indicate the same components. 6 is an AC power source. This AC power source 6 is placed at a location away from the track circuit 3.4, and is connected to the track circuit 3.4 via a cable line or the like at a power transmission end P1 set at a point near the boundary of the closed section. . The frequency f of the AC power source 6 is 3K under normal conditions.
) Iz is appropriate.

7 is the gauge voltage Vt at the power transmission end P1 and the gauge voltage V! at a point Pg set at a short distance X (for example, several tens of meters) from the power transmission end PL! This is a detection means for detecting which voltage difference ΔV, ΔV=VL−Vx. The detection means 7 is also connected to the AC power source 6.
Similarly, it is located at a remote location from the track circuit 3.4 and is connected to the track circuit 3.4 via a cable line or the like. Although the detection means 7 may be constituted by a differential transformer, a transistor differential amplifier, etc., this embodiment will be explained using a differential transformer as an example. That is, the detection means 7 detects the winding Nll to which the gauge voltage Vt is applied on the power transmission end vl side,
Gauge voltage V at a point Pi separated by a distance p#x from the power transmission end Pl! is applied @li N x, and the winding N 1 is coupled to these eight wires N 11 and Nz separately
2 and Nz are connected differentially, and the voltage difference ΔV is obtained between terminals 8 and 9.
= V 1 - V x is taken out.

In the present invention, the voltage difference Δ obtained as described above is
The distance statement to one train A1 is measured using a signal proportional to V-=V1-Vx. Next, the measurement principle will be explained.

First, the gauge voltage ■tension and track circuit current Ix at a point Pg that is a distance x away from the power transmission end Pl are VX = V 2 , cosh y (1-X ) + Zo,
I2.5inhy(1-X) , , (1) I x
= I2, cosh y(1-X)+(V
2/Zo) 5inhy(1-X) ,, (
2) However, γ is the propagation constant of the track circuit Zo is the characteristic impedance Gauge voltage v2 = 0 due to short circuit
Therefore, by substituting this into equation (1), we get

Vx = Zo, I 2.5inhy (L; L-X
) ・, , (3).

Next, by substituting x=O, v2-〇 into equations (1) and (2), the gauge voltage v1 and track circuit current 11 at the power transmission end P1 are obtained as follows.

V 1 =Z o , I 2 , s: nhll
,,,, (4) I □= I 2 , coshy
i,,,, (5) Here, Vl-Vx
= ΔV, formula (3) % formula %) Furthermore, from formulas (5) and (6), I 1 = ΔV , coshyJL/Z o(sin
h 11-3; nhy(fL −X ) ) =, −(
7) Here, since γX is small, equation (7) can be approximated as follows.

Ix=ΔV/(Zo, y,
Substituting L/It to find the short circuit impedance Z1, Z 1 = V t , Zo , y, X /ΔV=V
1. Z, X/ΔV = vs , Z, X/ (Vt-Vx)-C9) However,
Z is the rail impedance per unit length. In equation (9), the gauge voltage Vl, the rail impedance Z per unit length, and the point PK from the transmission end P1
If the distance #X is known, point Pl and point Px
Gauge voltage difference ΔV=V1-VK and feed end Pt
By detecting the voltage Vl, the short circuit impedance Z1 can be measured. As explained in FIG. 5, the short circuit impedance Z1 is approximately proportional to the distance gI from the power transmission end P1 to the train A1. Therefore, point Pt and point P! The train distance can be measured by detecting the gauge voltage difference ΔV=Vl−Vx at , and calculating the short circuit impedance Z1 based on the detection signal.

The short-circuit impedance Zr in the above equation (9) can be easily calculated using an electronic circuit. An example of this is shown in FIG. 2. The arithmetic circuit shown in FIG. 2 is a circuit that processes equation (9) as an exponential function, and the gauge voltage Vl and voltage difference ΔV=V1− given as analog quantities. Vx is each converted into a digital quantity by an analog/digital converter 10.11. Then, each digital signal is input to the logarithm table circuit 12.13 and converted into digital quantities 1ogVx and logΔV according to the logarithm of the amplitude of each voltage signal. Te(lag
V l-logΔ■) is calculated.

Next, this calculation result is input to the logarithm table circuit 15 and reconverted into a quantity according to the exponent. Thereby, short circuit impedance Z1 is calculated. The logarithm table circuit 15 adds singular condition correction to the orbit circuit. The data calculated in this way may be output as a digital quantity as is, or may be converted into an analog quantity by the digital/analog converter 16 and output.

As described above, in the present invention, the gauge voltage Vl at the power transmission end P1 and the point P! set near the power transmission end P1!
Gauge voltage at ■! Since it is equipped with means for detecting which voltage difference ΔV=Vx-Vx and uses a voltage signal proportional to this voltage difference ΔV=V1-V violet to measure the distance rl-fL to train A1, the voltage The detection means 7, such as a differential transformer that detects the difference ΔV=V1-Vx, does not need to be placed inside the track, and is installed in a monitoring room or the like away from the track using the AC power source 6.
and arithmetic equipment, etc., and connect the track circuit 3. with a cable line.
Just connect it to 4. Therefore, it is possible to realize a train distance measuring device that is easy to implement, has excellent practicality and economic efficiency, and does not interfere with track maintenance work. Furthermore, there is an advantage that the present invention can be applied even if the track circuit 3.4 is not insulated.

Furthermore, 4 of the detection means 7! When a failure such as a disconnection occurs in a line or cable, the voltage difference ΔV tends to increase, that is, the short-circuit impedance Zl decreases. The direction in which the short circuit impedance z1 becomes smaller is the direction in which the train distance statement becomes shorter. Therefore, fail-safe performance can be ensured against disconnection accidents and the like.

Effects of the Invention As described above, the present invention provides a device for measuring the distance from a certain point set on a track circuit to a track circuit short-circuit point caused by a train, in which the gauge voltage at the power transmission end set at the point is measured. and means for detecting a voltage difference between the line voltage and the gauge voltage at a point set near the power transmission end, and measuring the distance using a voltage signal proportional to the voltage difference obtained by the detection means. Because it is characterized by the fact that there is no need to install a transmitting device or a receiving coil within the track, it is easy to implement, highly practical and economical, does not interfere with track maintenance work, and is a non-insulated @ road circuit. It is possible to provide a train distance measuring device that can be applied to trains and has high fail-safe properties.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of the main part of the distance measuring device according to the present invention, FIG. 2 is a block diagram of the arithmetic circuit, FIG. 3 is a diagram showing the relationship between train distance and train speed control, The figure is a circuit diagram of a main part of a conventional train distance measuring device, and FIG. 5 is a diagram showing the relationship between train distance and short-circuit impedance. 3.4... Track circuit 6... AC power supply 7...
Detection means A1...Train Pi...Power transmission end
Pg...point v1, Vx...gauge voltage...train distance

Claims (3)

[Claims] (1) In a device that measures the distance from a certain point set on a track circuit to a track circuit short-circuit point caused by a train, the gauge voltage at the power transmission end set at the point and the gauge voltage set near the power transmission end are measured. A train distance measuring device comprising means for detecting a voltage difference with a track voltage at a point, and measuring the distance using a voltage signal proportional to the voltage difference obtained by the detecting means. (2) The train according to claim 1, wherein the distance is measured by a voltage signal proportional to the voltage difference detected by the detection means and a gauge voltage signal at the power transmission end. Distance measuring device. (3) After converting the voltage signal proportional to the voltage difference and the gauge voltage signal at the transmission end into a digital quantity according to the logarithm of the amplitude, find the difference between both voltage signals, and further convert it into a quantity according to the index. 3. The train distance measuring device according to claim 2, wherein the distance is measured by re-converting the distance.