JP2008265640A - Transmission device for track circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely prevent a transmitter from being failed due to shortcircuit by an axle and also improve power efficiency. <P>SOLUTION: The degree of modulation of the amplifying part 11 of a power amplifier 9 is variably controlled according to the voltage and the current actually transmitted to rails 2 for regulating the output of the amplifier 11 to a specified voltage and current. Since an excessive current does not need to flow through the rails 2 even when the position of the shortcircuit of the left and right side rails 2 by the axle 16 reaches the end of the transmission of the transmitter 3, the amplifier 11 and a matching transformer 4 are prevented from causing a defect or a trouble. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is for train detection and train control on rails constituting a track circuit in order to realize the functions of a railway signal security device such as a train detection device (TD device) and an automatic train control device (ATC device). It is related with the transmitter which transmits the signal current of.

  In a railway signal security device such as a TD device or an ATC device, a signal current is transmitted from a transmitter provided for each block section to a rail constituting a track circuit for train detection and train control. As shown in FIG. 3, the transmitter 20 includes a signal generator 21 that generates an ATC / TD signal, a power amplifier 22 that amplifies the generated ATC / TD signal, and sets each block interval from the amplified signal. And a band-pass filter (BPF) 23 for extracting a used signal and removing an unnecessary band and a noise component, and usually a signal current of an AC signal of several hundreds to several tens of kHz is passed through the rail. For this reason, a power amplifier 22 having an output of several watts to several tens of watts is used. As the power amplifier 22, a power amplifier that works at a B or AB bias operating point has been conventionally used. As these characteristics, it is necessary to obtain a stable characteristic by flowing a large idle current. For this reason, the power use efficiency of the power source is poor, the majority is about 40 to 50% efficiency, the power amplifier 22 itself consumes a lot of power, heat is large, and a large radiation fin and ventilation area are used for heat radiation. It was necessary to secure the implementation efficiency was poor.

  When the train 15 enters the track circuit nT transmitting signal current from the transmitter 20 using the power amplifier 22 to the rail 2 constituting the track circuit nT, the left and right rails 2 are short-circuited by the axle 16 of the train 15. The If the train 15 travels through the track circuit nT and the transmission end of the transmitter 20 is short-circuited by the axle 16, the transmitter 20 outputs an excessive current, causing a failure. In order to prevent the transmitter 20 from being deteriorated or broken due to a short circuit caused by the axle 16 of the train 15, as shown in Non-Patent Document 1, the iron loss transformer 24 and the rail 2 are connected to the axle 16 between the transmitter 20 and the rail 2. The current limiting function operates as a current limiting function so that a constant current does not flow in the rail 2 when a short circuit occurs in the rail 2, and functions as a buffer so that the rail short circuit does not affect the transmitter 20 A resistor 25 is provided. The iron loss transformer 24 is manufactured so as to increase transmission loss. The iron loss transformer 24 operates so that a short circuit on the secondary side does not affect the power amplifier 22 on the primary side, and transmits noise entering from the rail 2 side as necessary. A device having an insulation performance having an anti-noise characteristic is used so as not to be transmitted to the device side.

  In recent years, high-efficiency and high-speed power FETs (power field-effect transistors) have been developed and can be obtained relatively inexpensively, and a class D digital amplifier can be easily configured. This digital amplifier can realize a high efficiency amplification of about 90% by applying a PWM modulation method to power amplification and performing power amplification with a switching circuit. As shown in Patent Document 1, as shown in Patent Document 1, a transmitter such as an ATC device can be used. in use.

Track circuit Pages 61-63 Published by Japan Railway Electrical Engineering Association 1992 Japanese Patent Laid-Open No. 10-310056

  Even when a D-class amplifier having a high power supply efficiency is used as described above, in order to protect against an axle short-circuit, an iron loss transformer or the like can be used as in the case of using a conventional class B or AB amplifier. When the current limiting resistor is used, the power efficiency of the amplifier itself is good, but the overall power efficiency cannot be improved dramatically due to the power consumption in the iron loss transformer and the current limiting resistor.

  In addition, since the iron loss transformer has poor transmission efficiency, it is necessary to provide a margin for the amplifier in order to compensate for it with the output of the amplifier, and an amplifier with high performance is required. Further, there is a problem that heat is generated by the power consumed by the current limiting resistance.

  An object of the present invention is to provide a transmission device for a track circuit that solves such problems, reliably prevents a failure due to an axle short-circuit, and the like and dramatically improves power efficiency.

  A transmission device for a track circuit according to the present invention includes a transmitter, a matching transformer, a voltage sensor, and a current sensor, the voltage sensor detects a voltage output from the transmitter to a rail, and the current sensor includes: A current output from the transmitter to the rail is detected, and the transmitter includes a signal generator, a voltage / current detector, a power amplifier, and a low-pass filter (LPF). A voltage signal detected by the voltage sensor and a current value detected by the current sensor to detect the amount of change, and the power amplifier amplifies. And an amplifier that amplifies the power by inputting the signal generated by the signal generator, and the controller is responsive to changes in voltage and current detected by the voltage / current detector. The gain of the amplifier Feedback control, the LPF removes noise from the signal amplified by the power amplifier and passes only the necessary signal components to output to the rail side, and the matching transformer outputs the signal output from the transmitter. It supplies to a rail, It is characterized by the above-mentioned.

  According to the present invention, the gain of the amplifying unit of the power amplifier is variably controlled according to the amount of change in the voltage and current actually transmitted to the rail, and the output of the amplifying unit is set to the specified voltage and current. Even when the short-circuit position of the rail of the rail of the rail reaches the transmitter end of the transmitter, it is not necessary to send an excessive current to the rail, and it is possible to reliably prevent abnormalities and failures in the amplifier section and matching transformer with a simple configuration be able to.

  In addition, since the voltage and current output from the amplifying unit of the power amplifier are detected and feedback controlled, no extra power consumption is required, and the overall power efficiency can be dramatically improved, saving energy. Can be achieved.

  FIG. 1 is a block diagram showing the configuration of the transmission apparatus of the present invention. As shown in the figure, the transmitting device 1 of the ATC device transmits a signal current to the rail 2 constituting the track circuit, and the voltage value of the voltage supplied between the transmitter 3, the matching transformer 4 and the rail 2. And a current sensor 6 for detecting a current value of a current supplied to the rail 2. The transmitter 2 includes a signal generator 7, a voltage / current detector 8, a power amplifier 9, and a low-pass filter (LPF) 10. The signal generator 7 generates a TD signal and an ATC signal according to a command from the host device. The voltage / current detector 8 receives the voltage value detected by the voltage sensor 5 and the current value detected by the current sensor 6 and detects the amount of change. The power amplifier 9 includes an amplifying unit 11 and a control unit 12. The amplifying unit 11 receives the signal generated by the signal generating unit 7 and amplifies power by a PWM modulation method. The control unit 12 controls the degree of modulation of the amplification unit 11 in accordance with the voltage and current changes detected by the voltage / current detection unit 8. The LPF 10 removes noise from the signal amplified by the power amplifier 9 and passes only necessary signal components. The matching transformer 4 matches the output of the transmitter 3 and the rail 2. This matching transformer 4 is provided with an insulation performance having noise resistance characteristics so as not to transmit the incoming noise from the rail 2 to the transmitter 3 if necessary.

  The operation of transmitting a signal current to the rail 2 of the track circuit nT set by the track insulation 13 and the impedance bond 13 in the transmitter 1 will be described with reference to the flowchart of FIG.

  The transmitter 3 amplifies the signal generated by the signal generator 7 so as to have a predetermined voltage and current in the amplifier 11 of the power amplifier 9, and the amplified signal current is passed from the LPF 10 through the matching transformer 4 to the track circuit nT. Is always transmitted to the rail 2 (step S1). When this signal current is transmitted to the rail 2, the voltage sensor 5 detects the voltage value of the voltage supplied between the rails 2 from the power amplifier 9 via the matching transformer 4, and the current sensor 6 detects the rail 2 Is detected and input to the voltage / current detector 8 (step S2). When the train 15 enters the track circuit nT in this state, the signal current transmitted to the left and right rails 2 is short-circuited by the axle 16 of the train 15, and as the train 15 proceeds, the short-circuit by the axle 16 of the left and right rails 2 is performed. The position moves to the transmitting end side from the transmitter 3. For this reason, the voltage and current supplied to the rail 2 output from the transmitter 3 sequentially change as the train 15 travels, and the voltage detected by the voltage sensor 5 and the current sensor 6 detect it. The current changes. The voltage / current detector 8 detects the voltage value of the voltage detected by the voltage sensor 5 and the amount of change in the current value of the current detected by the current sensor 6, and outputs the detected amount of change to the controller 12 ( Step S3). The control unit 12 variably controls the modulation degree of the amplification unit 11 according to the input voltage and current variation, and feedback-controls the output of the amplification unit 11 so as to become a predetermined voltage and current (step S4). ).

  In this way, the modulation degree of the amplifying unit 11 of the power amplifier 9 is variably controlled according to the amount of change in the voltage and current actually transmitted to the rail 2 so that the output of the amplifying unit 11 is set to the specified voltage and current. Thus, even when the short-circuit position of the left and right rails 2 by the axles 16 reaches the transmitting end of the transmitter 3, it is not necessary to supply an excessive current to the rails 2, and abnormalities or failures occur in the amplifying unit 11 or the matching transformer 4. It can be prevented from occurring.

  In addition, since the voltage and current output from the amplifying unit 11 of the power amplifier 9 are detected and feedback controlled, no extra power consumption is required, and the overall power efficiency can be dramatically improved. Energy saving can be achieved.

  In the above description, the case where a digital amplifier is used as the amplifying unit 11 of the power amplifier 9 has been described. However, an analog amplifier is used as the amplifying unit 11, and The amplification degree may be feedback controlled according to the amount of change.

  Further, the voltage sensor 5 and the current sensor 6 have been described for detecting the voltage and current output from the matching transformer 4 to the rail 2, but the voltage and current output from the transmitter 3 to the matching transformer 4 are detected. Also good.

It is a block diagram which shows the structure of the transmitter of this invention. It is a flowchart which shows operation | movement of a transmitter. It is a block diagram which shows the structure of the conventional transmitter.

Explanation of symbols

1; Transmitter, 2; Rail, 3; Transmitter, 4; Matching transformer, 5; Voltage sensor,
6; current sensor, 7; signal generation unit, 8; voltage / current detection unit, 9; power amplifier,
10; LPF, 11; amplification unit, 12; control unit, 15; train, 16;

Claims (1)

A transmitter, a matching transformer, a voltage sensor and a current sensor;
The voltage sensor detects a voltage output from the transmitter to a rail,
The current sensor detects a current output from the transmitter to a rail,
The transmitter includes a signal generator, a voltage / current detector, a power amplifier, and a low pass filter (LPF).
The signal generator generates a control signal according to a command from the host device,
The voltage / current detector detects the amount of change by inputting the voltage value detected by the voltage sensor and the current value detected by the current sensor,
The power amplifier includes an amplifying unit and a control unit, the amplifying unit inputs a signal generated by the signal generating unit and amplifies the power, and the control unit detects the voltage and current detected by the voltage / current detecting unit. Feedback control of the gain of the amplification unit according to the change of
The LPF removes noise from the signal amplified by the power amplifier and passes only necessary signal components to output to the rail side.
The matching transformer supplies a signal output from the transmitter to a rail.

Images