JP5268993B2 - Digital signal track circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To dramatically enhance the noise resistance of a low-frequency track circuit device, and to attain multi aspect, without broadening the operating frequency range. <P>SOLUTION: A transmitter 2b generates a digital modulation wave by modulating, using an FSK (frequency-shift keying) method, with respect to a carrier frequency existing in the gaps of the fundamental frequency between alternating current powered section and its higher-harmonic waves, amplitude modulates the generated digital modulation wave by means of an analog modulation wave based on signal aspect information at a degree of amplitude modulation that leaves the necessary minimum amplitude components of the digital modulation wave and at an amplitude modulation frequency of a constant period to generate a digital-analog signal wave, and transmits it to a track circuit 2T so that the multi aspect is attained. The receiver 3b receives the digital-analog signal wave transmitted to the track circuit 2T, separates the digital modulation components, and improves the noise resistance by testing the period and the order of the frequency of the digital modulation components that are separated. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a digital signal track circuit that detects the presence of a train using a rail.

  The conventional low-frequency track circuit includes a binary track circuit that verifies both the phase difference from the transmission signal and the reception level, and, as shown in Patent Document 1, the low-frequency signal for train detection at the transmission end is classified as an information type. The amplitude is modulated by switching the modulation frequency by the power and transmitted to the rail through the impedance bond. At the receiving end, the level of the signal from which the amplitude variation of the amplitude signal of the received signal is removed is detected to detect the presence of the train, An intermittent wave amplitude modulation / multi-display method is used that selects and determines the modulation frequency of the received signal and outputs the information type.

  When these low-frequency track circuits are used to detect a train in a control section, there are malfunctions due to transient noise such as a notch change of a conventional resistance-controlled vehicle and electric vehicle noise such as wheel arcing noise caused by a wheel short circuit. In addition, malfunctions affected by inverter control noise from inverter-controlled vehicles that are rapidly spreading in recent years have been reported. All of these malfunctions are malfunctions caused by vehicle noise when a train is present in the control section, and are therefore dangerous malfunctions that determine that the train is present as a non-present line.

  Electric cars, such as resistance cars and inverter-controlled cars, have a certain range of traction force, travel speed, acceleration / deceleration, etc., and a certain range of frequency characteristics, time characteristics, etc. of electric vehicle noise generated from these factors. is there. From the characteristics of the electric vehicle noise obtained so far, as shown in FIG. 6 (a), there is no periodicity such as wheel arcing when the wheels are short-circuited, and as shown in FIG. 6 (b), chopper control is performed. Various types of noise have been reported, such as periodic noise such as cars, and noise in which the frequency of a VVVF car continuously changes. In order to reliably prevent a malfunction on the dangerous side where the train is not present, it is necessary to eliminate the influence of all these noises.

  Patent Document 2 discloses a low-frequency track circuit device that eliminates these electric vehicle noises and dramatically improves noise resistance. The low-frequency track circuit device disclosed in Patent Document 2 alternately turns signals of two types having a small frequency separation from the fundamental frequency of the basic frequency of the AC electrification section and its higher harmonics from the transmitting end to the basic frequency. The FSK wave signal switched at a low cycle is transmitted to the rail of the track circuit, and the receiving end separates the train detection signal transmitted to the rail into two types of frequency signals and separates the two types of frequency signals. Complementarity test is performed to determine whether there is complementarity. If the signals of two kinds of frequencies have complementarity, it is determined that there is no train in the track circuit, and when the train detection signal is not received and the two kinds of received frequencies If the signal does not have complementarity, it is determined that there is a train in the track circuit and electric vehicle noise is eliminated, so that noise resistance is drastically improved.

  The low-frequency track circuit device disclosed in Patent Document 2 has improved noise resistance, but has not been able to achieve multiple indications.

  An object of the present invention is to provide a digital-analog signal track circuit device that can dramatically improve noise resistance and can achieve multiple indications without widening the use frequency band.

The digital-analog signal track circuit device of the present invention has a transmitter connected to one end of each track circuit and a receiver connected to the other end, and the transmitter is a digital modulated wave generator. And an analog modulation wave generation unit, an amplitude modulation unit, and a transmission unit. The digital modulation wave generation unit has an amplitude with respect to the carrier frequency in the gap between the fundamental frequency of the AC electrification section and a plurality of higher harmonics thereof. A digital modulation wave is generated by modulation without modulation, and an analog modulation wave generation unit generates an analog modulation wave that is separable from the frequency component of the digital modulation wave at a constant period based on the signal display information, and an amplitude modulation unit The amplitude modulation degree is such that at least the necessary minimum amplitude component of the digital modulation wave is left by the analog modulation wave generated by the analog modulation wave generation unit from the digital modulation wave generated by the digital modulation wave generation unit. A digital signal is generated by amplitude modulation with a fixed amplitude modulation frequency. The transmitter transmits the digital signal generated by the amplitude modulator to each track circuit. The receiver displays the signal with the train detection processor. A detection processing unit, the train detection processing unit detects a digital modulation wave without amplitude modulation from a digital signal wave received from the track circuit, and demodulates the digital modulation wave, and the frequency period of the digital signal obtained When the order is verified and the frequency period and the order are arranged in a fixed period and a fixed order, it is determined that there is no train in the track circuit, and the digital signal transmitted to the track circuit is not received and reception time constant period of the frequency of the digital signal obtained by demodulating the digital modulated wave, if you are not aligned in a certain order is determined that there is a train on the track circuit, a train in the track circuit not The signal indication detection processing unit detects a signal indication of a corresponding section by demodulating an analog modulation wave having a constant amplitude modulation frequency from a digital signal wave received from the track circuit. To do.

  The present invention generates a digital modulated wave by modulation without amplitude modulation with respect to a carrier frequency in the gap between the fundamental frequency of the AC electrification section and a plurality of higher harmonics thereof, and carries the generated digital modulated wave Noise resistance can be ensured by using a signal wave.

In addition, a digital modulated wave is generated and an analog modulated wave is generated based on the signal display information, and at least the minimum amplitude component of the digital modulated wave is left by the generated analog modulated wave. Since the digital signal is generated by performing amplitude modulation with an amplitude modulation frequency of a predetermined period and with an amplitude modulation frequency of a fixed period, and transmitted to the track circuit, multiple display can be achieved.

Furthermore, the digital analog signal wave transmitted to the track circuit is received, the digital modulated wave is separated, and the frequency period and order of the separated digital modulated wave are verified so that the frequency is proportional to the speed of the VVVF vehicle or the like. Even if the component changes, since it is not a pseudo signal unless acceleration, deceleration, acceleration or deceleration, acceleration, deceleration is switched for a certain short time, electric vehicle noise can be eliminated, and noise resistance Can be improved dramatically.

It is a block diagram which shows the structure of the digital signal track circuit apparatus of this invention. It is a block diagram which shows the structure of a transmitter. It is explanatory drawing which shows the structure of a digital modulation wave. It is a block diagram which shows the structure of a receiver. It is explanatory drawing which shows the structure of a digital signal wave. It is a wave form diagram which shows the noise which generate | occur | produces with an electric vehicle.

  FIG. 1 is a block diagram showing a configuration of a digital signal track circuit device of the present invention. As shown in the figure, the digital signal track circuit device includes transmitters 2a to 2c connected to boundaries on the train advance side of each track circuit 1T to 4T using rails on which the train 1 travels, and each track circuit 1T to It has receivers 3a to 3d connected to the boundary side on the 4T train entry side.

  As shown in the block diagram of FIG. 2, the transmitter 2 includes a digital modulation wave generation unit 4, an analog modulation wave generation unit 5, an amplitude modulation unit 6, and a transmission unit 7. The digital modulation wave generation unit 4 performs amplitude modulation on the carrier frequency between the fundamental frequency 50 Hz or 60 Hz of the AC electrification section and its higher order harmonics (100 Hz, 150 Hz,..., 120 Hz, 180 Hz,...). Generates a digital modulated wave with no modulation. For example, the frequency fcHz between the basic frequency 50 Hz or 60 Hz of the AC electrification section and its higher harmonics (100 Hz, 150 Hz,..., 120 Hz, 180 Hz,...), And the frequency separation is small with respect to at least 2 A digital modulated wave is generated by modulating the frequency of the wave with a frequency shift keying (FSK) method using the carrier frequency as a carrier frequency. That is, as shown in the spectrum of FIG. 3A, the frequency of two waves of the frequency (fc−fs) and the frequency (fc + fs) generated by the frequency fc and the transition frequency Δf = ± fs is used as the carrier frequency and modulated by the FSK method. Then, as shown in the waveform diagram of FIG. 3B, the amplitude of a digital modulated wave having a constant amplitude arranged in a constant keying period fk in the order of the signal of frequency (fc−fs) and the signal of frequency (fc + fs). Output to the modulation unit 6.

The analog modulation wave generating unit 5 has an amplitude modulation frequency of a constant period of the period fm as shown in the upper waveform diagram of FIG. 5B based on the signal display information sent through the condition communication circuit 8 . An analog modulated wave is generated and output to the amplitude modulator 6. The amplitude modulation unit 6 leaves at least the minimum amplitude component of the carrier signal wave, which is a digital modulation wave, by using the analog modulation wave generated by the analog modulation wave generation unit 5 from the digital modulation wave generated by the digital modulation wave generation unit 4. As shown in the spectrum diagram of FIG. 5 (a) and the waveform diagram of the lower diagram of FIG. A digital signal in a band including a sideband component with modulation is generated. The transmission unit 7 transmits the digital signal wave generated by the amplitude modulation unit 6 to each of the track circuits 1T to 4T.

As shown in the block diagram of FIG. 4, the receiver 3 includes a train detection processing unit 9 and a signal indication detection processing unit 10. The train detection processing unit 9 includes a BPF 11, a digital modulation wave demodulation unit 12, and a logic unit 13. The BPF 11 detects a digital modulation wave without amplitude modulation from the digital signal waves received from the track circuits 1T to 4T and outputs the digital modulation wave to the digital modulation wave demodulation unit 12. The digital modulation wave demodulator 12 demodulates the input digital modulation wave using, for example, the FSK method and outputs the demodulated wave to the logic unit 13. The logic unit 13 detects whether or not the train 1 is present on each track circuit 1T to 4T based on the input digital signal. For example, when the frequency period and order of digital signals are verified, and the frequency period and order are arranged in a fixed period and a predetermined order, it is determined that there is no train in the track circuit, and the track circuits 1T to 4T When the transmitted signal wave is not received and when the reception times of the received frequencies are not arranged in a fixed cycle and in a fixed order, it is determined that there is a train on the track circuit.

The signal indication detection processing unit 10 includes a BPF 14, an analog modulated wave demodulation unit 15, and a logic unit 16. The BPF 14 detects an analog modulation wave having an amplitude modulation frequency fm having a fixed period from the digital signal wave received from each of the track circuits 1T to 4T and outputs the analog modulation wave to the analog modulation wave demodulation unit 15. The analog modulated wave demodulator 15 demodulates the input analog modulated wave and outputs it to the logic unit 16. The logic unit 16 detects and outputs the signal indication of the corresponding section by the input analog modulated wave .

  A process for detecting whether or not the train 1 is present on the track circuit 2T, for example, in this digital signal track circuit device will be described.

  When the train 1 is not present on the track circuit 2T, the digital modulation wave generation unit 4 uses, for example, fc = 80 Hz as the fundamental frequency, and the frequency (fc−fs) generated at the transition frequency fs = 5 Hz = 75H. And the frequency (fc + fs) = 85 Hz as two carrier frequencies, modulated by the FSK method, and arranged in the order of the frequency (fc−fs) signal and the frequency (fc + fs) signal at a constant keying period fk = 1 Hz. A digital modulation wave having a constant amplitude is output to the amplitude modulation unit 6. On the other hand, the analog modulated wave generator 5 generates an analog modulated wave based on the signal display information sent via the condition communication circuit 8 and outputs it to the amplitude modulator 6. The amplitude modulation unit 6 leaves at least a minimum amplitude component of the carrier signal wave, which is a digital modulation wave, from the digital modulation wave generated by the digital modulation wave generation unit 4 by the analog modulation wave generated by the analog modulation wave generation unit 5. Transmitting unit 7 generates a digital signal signal in a band including sideband components accompanied by amplitude modulation for multiple display by performing amplitude modulation at a certain amplitude modulation degree and with an amplitude modulation frequency fm = 5 Hz of a fixed period. And the digital signal from the transmitter 7 is transmitted to the track circuit 2T.

  Thus, multiple display can be achieved by transmitting the digital signal of the band including the sideband component with amplitude modulation for multiple display from the transmitter 2b to the track circuit 2T.

The digital signal transmitted to the track circuit 2T is received by the receiver 2. The train detection processing unit 9 of the receiver 2 detects a digital modulation wave without amplitude modulation from the digital signal wave received from the track circuit 2T, demodulates the detected digital modulation wave by the FSK method, and the frequency of the demodulated digital signal If the frequency and order of the frequencies are arranged in a fixed period and a predetermined order, it is determined that there is no train in the track circuit 2T, and a signal indicating that there is no train line is sent to the track circuit 2T. Output.

This sends a digital numeric and virtual analog signal wave from the transmitter 2b to the track circuit 2T as receives a digital numeric and virtual analog signal wave is transmitted to the track circuit 2T at the receiver 3b demodulates and separates the digital modulation wave, the digital demodulated Even if the frequency component changes in proportion to the speed of a VVVF vehicle, etc., by checking the signal frequency cycle and order, acceleration, deceleration, acceleration or deceleration, acceleration, deceleration is switched to a fixed short time. As long as it is not a pseudo signal, electric vehicle noise can be eliminated, and noise resistance can be dramatically improved.

On the other hand, the signal display detection processing unit 10 of the receiver 2 detects an analog modulation wave having a constant period of amplitude modulation frequency fm = 5 Hz from the digital signal wave received from the track circuit 2T, and demodulates the detected analog modulation wave . The signal display in the section of the track circuit 2T is detected and output by the demodulated analog modulated wave .

  In this state, when the train 1 enters the track circuit 2T and the receiver 3b does not receive the digital signal wave transmitted to the track circuit 2T, and the frequency of each frequency of the received digital signal wave is arranged in order at a constant cycle. If not, the train detection processing unit 9 determines that there is a train on the track circuit 2T, and outputs a signal indicating that the train 1 is on the track circuit 2T.

  In this state, as shown in FIG. 6 (a), there is no periodicity such as wheel arcing when the wheel of the train 1 is short-circuited, and as shown in FIG. Even when various noises such as certain noises, noises of VVVF cars, etc. whose frequency changes continuously enter the receiver 3b, the receiver 3b receives a digital signal wave in which the frequency cycle is arranged in order at a constant cycle. Therefore, it is determined that there is a train on the track circuit 2T, and a malfunction due to noise when the train 1 is present on the track circuit 2T prevents a dangerous malfunction that causes the train not to exist. Can do.

In the above description, when a digital modulation wave is generated by modulating the frequency fcHz between the fundamental frequency of the AC electrification section and its higher order harmonics by the FSK method in the digital modulation wave generation unit 4 of the transmitter 2 as a train detection signal. However, the digital modulation wave may be generated by modulating the phase shift keying (PSK) method or the MSK method which is a kind of the narrow band FSK method.

1; train, 2; transmitter, 3; receiver, 4; digital modulation wave generator,
5; Analog modulation wave generation unit, 6; Amplitude modulation unit, 7; Transmission unit, 8; Condition communication circuit,
9; Train detection processing unit, 10; Signal indication detection processing unit, 11; BPF,
12: Digital modulation wave demodulating section, 13: Logic section, 14: BPF,
15: Analog modulation wave demodulating unit, 16: Logic unit.

Japanese Examined Patent Publication No. 4-74225 JP 2009-179214 A

Claims (1)

Having a transmitter connected to one end of each track circuit and a receiver connected to the other end;
The transmitter includes a digital modulation wave generation unit, an analog modulation wave generation unit, an amplitude modulation unit, and a transmission unit, and the digital modulation wave generation unit includes a plurality of fundamental frequencies and higher harmonics of an AC electrification section. A digital modulated wave is generated by modulating the carrier frequency in the frequency gap without amplitude modulation, and the analog modulated wave generating unit separates the frequency component of the digital modulated wave with a constant period based on the signal display information. A possible analog modulation wave is generated, and the amplitude modulation unit generates at least the minimum necessary digital modulation wave by the analog modulation wave generated by the analog modulation wave generation unit from the digital modulation wave generated by the digital modulation wave generation unit. The amplitude modulation degree is sufficient to leave the amplitude component of the signal, and the digital signal is generated by performing amplitude modulation with the amplitude modulation frequency of a fixed period, and the transmission unit is generated by the amplitude modulation unit Was digital numeric and virtual analog signal waves transmitted to the track circuit,
The receiver includes a train detection processing unit and a signal indication detection processing unit, and the train detection processing unit detects a digital modulation wave without amplitude modulation from a digital signal wave received from a track circuit , and the digital modulation The frequency period and order of the digital signal obtained by demodulating the wave are verified, and when the frequency period and order are arranged in a predetermined period and a predetermined order, it is determined that there is no train in the track circuit, When the digital signal obtained by demodulating the digital modulated wave is not received when the digital signal transmitted to the track circuit is not received and when the reception time of the frequency of the digital signal is not arranged in a fixed period and in a fixed order determined, detects a non-rail train in the track circuit, the signal current示検knowledge processing unit, an analog modulated wave of the amplitude modulation frequency having a predetermined period from digital numeric and virtual analog signal wave received from the track circuit Low-frequency digital numeric and virtual analog signal track circuit apparatus characterized by detecting the signal aspect of the relevant section and tone.

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