JP4658575B2 - High frequency induction preventing apparatus and method for railroad crossing controller - Google Patents

Description

  The present invention relates to a high-frequency induction preventing apparatus and method for a crossing controller that prevents a high-frequency induction failure in an open circuit type crossing controller that detects a train at the end point of a crossing alarm.

  As shown in FIG. 5, the railroad crossing controller (H type, 8.5 to 10.5 kHz) includes a closed circuit type railroad crossing controller 101 installed at the starting point and an open circuit type railroad crossing installed at the end point. It comprises a controller 102, a power converter 104 installed at the railroad crossing 103, MR relays (reception relays) 105, 106, a rectifier 107, a storage battery 108, and the like.

  The closed-circuit type railroad crossing controller 101 outputs a transmission voltage (8.5 to 9.3 kHz) from a track (sending) terminal connected to the rail 109 via the sending / receiving cable 110, and the rail 109 via the sending / receiving cable 110. The received voltage is input from the track (receiving) terminal connected to. When there is no train, a closed circuit is formed by the rail 109, so that a voltage higher than a predetermined value is output from the relay terminal, and the MR relay 106 is always operating. When the train enters the vicinity of the starting point, the received voltage is lowered by short-circuiting between the track (sending) terminals or between the track (receiving) terminals by the axle of the train, and the output voltage of the relay terminal is also lowered, so that the MR relay 106 becomes inactive and creates a condition for starting an alarm (and crossing of the railroad crossing) (Patent Document 1).

The open circuit type railroad crossing controller 102 outputs a transmission current (9.5 to 10.5 kHz) from the track terminal connected to the rail 109 through the sending and receiving cable 111. When there is no train, since an open circuit is formed between the rails 109, the output of the current detector for detecting the transmission current is small, the voltage at the relay terminal is small, and the MR relay 105 is always inoperative. When the train enters the vicinity of the end point (the train passes the railroad crossing 103), the transmission current increases due to a short circuit between the track terminals by the axle of the train, and the output voltage of the relay terminal becomes a predetermined value or more. Thus, the MR relay 105 operates to create a condition for terminating the alarm (and the level crossing interruption).
Japanese Patent No. 2613582

  A malfunction of the open circuit type railroad crossing controller should never be caused because the alarm (and crossing of the railroad crossing) will be terminated even if the train is not passing through the railroad crossing. However, with regard to the H-type open circuit type railroad crossing controller, an interruption failure that is presumed to be caused by a high frequency induction failure actually occurred. The same event occurred multiple times, possibly due to illegal civil radio (hereinafter referred to as illegal CB) on a large vehicle traveling on an adjacent national road.

  A test was conducted to investigate the cause of this high frequency induction disturbance. FIG. 6 shows a malfunction electric field strength level as a result of the test. The gray range is the malfunctioning range. The failure occurred in the third harmonic of 81 MHz, not the 27 MHz fundamental of illegal CB. The resistance of the level crossing controller is only 120.66 dBμV / m with respect to the electric field strength of 128.66 dBμV / m at the frequency, and an obvious failure occurs. As can be seen from FIG. 6, there is no problem at 27 MHz or lower and 172 MHz or higher. In fact, it is concluded that an illegal CB fundamental wave, a second harmonic, and a third harmonic influence each other, and as a result of the combination, an interruption failure occurs. However, it is the third harmonic that mainly caused malignant damage.

(Object of invention)
An object of the present invention is to provide a high-frequency induction preventing apparatus and method for a railroad crossing controller capable of preventing high-frequency induction generated in an open circuit type railroad crossing controller with a rail and a power line as an aerial line at low cost. It is.

In order to achieve the above object, according to the present invention, the open circuit type railroad crossing controller is connected in series to each track terminal and power supply terminal line of the open circuit type railroad crossing controller. A filter for attenuating a frequency higher than the signal frequency of the above, and comprising only a coil around an iron-silicon-aluminum magnetic core, the high frequency induction by the fundamental wave and harmonics of illegal civil radio The present invention provides a high-frequency induction preventing device for a crossing controller that is to be prevented.

Further, the present invention according to claim 2 is provided with a filter for attenuating a frequency higher than the signal frequency of the open circuit type railroad crossing controller in each line of each track terminal and power supply terminal of the open circuit type railroad crossing controller. Railroad crossing controller connected in series, wherein the filter is composed only of an iron-silicon-aluminum magnetic core and a coil is wound to prevent high-frequency induction due to fundamental waves and harmonics of illegal civil radio. This is a high frequency induction prevention method.

  ADVANTAGE OF THE INVENTION According to this invention, a rail and a power source line can become an aerial line, and can prevent the high frequency induction which generate | occur | produces in an open circuit type railroad crossing controller at low cost.

  The best mode for carrying out the present invention is as described in Examples described later.

  FIG. 1 is a diagram showing an open circuit type railroad crossing controller having a high-frequency induction preventing apparatus according to an embodiment of the present invention. A high frequency induction preventing device 2 is connected to the track terminal and the DC power supply terminal of the open circuit type railroad crossing controller 1. The track terminal of the high-frequency induction preventing device 2 is attached so as to be electrically connected to the rail 4 via the incoming / outgoing cable 3, and the DC power supply terminal is connected to the DC power supply in the railroad crossing equipment box (not shown) via the control cable 5. Connected. The attachment point of the sending / receiving cable 3 to the rail 4 is a point that is, for example, 20 m or more away from the railroad crossing 6 in the train traveling direction. The open circuit type railroad crossing controller 1 and the high frequency induction preventing device 2 are housed in an outer box 7 for the railroad crossing controller.

  A configuration example of the open circuit type railroad crossing controller 1 is shown in FIG. The open circuit type railroad crossing controller 1 includes a transmitter 8 and a receiver 9. In the transmitter 8, the oscillator 10 outputs a signal having a predetermined frequency in a range of 9.5 to 10.5 kHz, for example, and a waveform shaping filter 11 that shapes the square wave signal of the oscillator 10 into an equivalent sine wave, and an output switch 12. (Switched to either 1/1 or 1/2), through the power amplifier 13, the output transformer 14, and the transmission filter 15, through the current detector 16 such as a current transformer, for example, from the track terminal 17 to the rail 4 And output in the form of transmission current. The transmission current passing through the current detector 16 increases as the train is closer. Therefore, the value of the current detected by the current detector 16 also increases.

  The current detected by the current detector 16 is sent to the receiver 9. In the receiver 9, the detected current includes an input attenuator 18, a sensitivity adjuster 19 including correction of sensitivity according to the cable length, an active filter 20, an amplifier 21, a Schmitt circuit 22 having hysteresis characteristics, a power amplifier 23, and an output. A DC voltage is output to the relay terminal 26 via the transformer 24 and the rectifier 25, and at the same time, an indicator lamp 27 (for example, a green light emitting diode) is turned on to indicate that there is an output at the relay terminal 26. Railway signal security devices use relays to ensure asymmetry in the direction of failure. The Schmitt circuit 22 is used to stably drive a relay connected to the relay terminal 26 (MR relay 105 in FIG. 5). If a voltage higher than a predetermined voltage is input to the Schmitt circuit 22 by illegal CB high frequency induction, the relay will malfunction.

  The failure detection circuit 28 determines the soundness of the active filter 20 and stops the power supply to the amplifier 21 when a failure is detected. The magnitude of the output of the active filter 20 is displayed on the reception level indicator 30 by the indicator drive circuit 29.

  A configuration example of the high-frequency induction preventing device 2 is shown in FIG. Between each track terminal 31 on the open circuit type railroad crossing controller 1 side and each track terminal 32 on the rail 4 side and each DC power source terminal 33 on the open circuit type railroad crossing controller 1 side and each on the power supply and control cable 5 side Four low pass filters 35 for attenuating frequencies higher than the signal frequency of the open circuit type railroad crossing controller 1 are connected in series with the DC power supply terminal 34. That is, the low pass filter 35 is connected in series to each track terminal 17 and each DC power supply terminal 36 of the open circuit type railroad crossing controller 1. The low-pass filter 35 is composed of an iron-silicon-aluminum magnetic core (a magnetic core obtained by sintering iron, silicon, and aluminum as a powder: trade name: Sendust core) with a coil wound (for example, two turns). .

  The low-pass filter 35 passes the signal of the open circuit type railroad crossing controller 1 of about 10 kHz, and the rails 4 and DC are generated by the illegal CB fundamental wave (27 MHz), second harmonic (54 MHz), and third harmonic (81 MHz). A power line or the like becomes an aerial line to cut off high frequency induction generated in the open circuit type railroad crossing controller 1. Further, since the low pass filter 35 is only one using an iron-silicon-aluminum magnetic core, the cost can be reduced.

  FIG. 4 shows the test result of the malfunction electric field strength level of the open circuit type railroad crossing controller 1 having the high frequency induction preventing device 2 according to the present invention. According to this, the malfunctioning electric field strength level of the open circuit type railroad crossing controller 1 is much higher than the electric field strength levels of the fundamental wave (27 MHz), the second harmonic (54 MHz), and the third harmonic (81 MHz) of the illegal CB. Since it is large, high frequency induction can be sufficiently prevented.

  Normally, high frequency induction prevention measures are taken with a filter using a ferrite core (98% of these measures are taken with a filter using a high quality ferrite core). However, in the tests so far, the measure of putting the ± line of the rail terminal of the railroad crossing controller and attaching a general clamp type ferrite core to it is the signal frequency (9.5 to 10) of the H type railroad crossing controller. It has been found that the current of the rail itself is reduced and the normal operation of the crossing controller is hindered. In ordinary high frequency induction prevention measures such as personal computers, the ± wires are put together and a clamp type ferrite core is attached. This measure is effective for high-frequency induction failure caused by common-mode current (common mode) such as a personal computer, but two rails are mainly used for different-phase current (normal mode) like a railroad crossing controller. Therefore, it is less effective for high frequency induction disturbances. In the case of a railroad crossing controller, the effect cannot be expected unless the low pass filter 35 is connected in series to each line of the track terminal and the power supply terminal.

  In addition, a low-pass filter using an iron-silicon-aluminum magnetic core is useful as a low-pass filter for preventing high-frequency induction of a crossing controller because it has a very low resistance in the operating frequency band of the crossing controller.

It is a figure which shows the open circuit type crossing controller which has a high frequency induction | guidance | derivation prevention apparatus which is one Example of this invention. It is a block diagram which shows the structural example of the open circuit type railroad crossing controller in FIG. It is a circuit diagram which shows the structural example of the high frequency induction prevention apparatus in FIG. It is a figure which shows the test result of the malfunctioning electric field strength level of the open circuit type railroad crossing controller which has a high frequency induction | guidance | derivation prevention apparatus by this invention. It is a figure which shows an example of the system configuration | structure of a level crossing control facility containing the conventional closed circuit type crossing controller and an open circuit type crossing controller. It is a figure which shows the test result of the malfunctioning electric field strength level of the conventional open circuit type railroad crossing controller.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Open circuit type level crossing controller 2 High frequency induction prevention device 4 Rail 5 Power supply and control cable 6 Level crossing 8 Transmitter 9 Receiver 16 Current detector 17 Track terminal 26 Relay terminal 31, 32 Track terminal 33, 34 DC power supply terminal 35 Low pass Filter 36 DC power supply terminal

Claims (2)

Each track terminal of the open circuit type railroad crossing controller and each line of the power supply terminal are connected in series with each other, and have a filter that attenuates a frequency higher than the signal frequency of the open circuit type railroad crossing controller, A high frequency induction preventing device for a railroad crossing controller comprising only iron-silicon-aluminum coils wound with a coil to prevent high frequency induction by fundamental waves and harmonics of illegal civil radio. . A filter that attenuates a frequency higher than the signal frequency of the open-circuit type railroad crossing controller is connected in series to each track terminal and power supply terminal line of the open-circuit type railroad crossing controller. A method for preventing high-frequency induction of a railroad crossing controller , comprising only a silicon-aluminum magnetic core wound with a coil to prevent high-frequency induction due to fundamental waves and harmonics of illegal civil radio .

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