JP4958307B2 - Low frequency track circuit - Google Patents

Description

  The present invention relates to a low-frequency track circuit device that detects the presence of a train using rails, and particularly relates to improvement of noise resistance and extension of track circuit length.

  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 intermittent period and level of a signal that is intermittent in a low period. Coded track circuit is used to verify.

  When a train in a control section is detected using these low-frequency track circuits, there is a malfunction due to excessive noise such as 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 where the train is not present.

In addition, in a multi-rail circuit in which both rails are insulated at the boundary on both sides of the track circuit and the control section is clearly divided so that the signal current does not flow to the adjacent track circuit, when one rail breaks, It is necessary to prevent malfunctions in a 100% unbalanced state assuming that all the current flows only through the other rail, and the reception voltage of the train detection signal must be increased, so the control distance is short. As a result, practicality is impaired.
JP-A-6-127387

  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. 5 (a), there is no periodicity such as wheel arcing when the wheels are short-circuited, and as shown in FIG. 5 (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.

  It is an object of the present invention to provide a low-frequency track circuit device that can significantly improve noise resistance by eliminating these electric vehicle noises and can extend the track circuit length beyond the present level.

The low-frequency track circuit device of the present invention has a transmitter and a receiver, and the transmitter is based on the FSK method using the fundamental frequency of the AC electrification section and the frequency f0 between its higher harmonics as the fundamental frequency. Modulate and generate FSK wave signals that are alternately switched in a low cycle between two types of frequency f1 = (f0−Δf) and frequency f2 = (f0 + Δf) with a small frequency separation. The amplified train detection signal is transmitted to the rail, and the receiver has two sets of band filters and a phase correction test unit, and the two sets of band filters have two types of train detection signals transmitted to the rail. The signal is separated into signals of frequencies f1 and f2, and the phase correction verification unit determines whether or not the two kinds of signals of frequencies f1 and f2 separated by the two sets of bandpass filters are alternately alternating with the modulation period. Check complementarity test No 2 when the type of a frequency f1, complementary to f2 signal, judges no train track circuit, determines that there is a train in the track circuit when not receiving the train detection signal, chopper control wheel or the like in this state If there is either a signal of frequency f1 or a signal of frequency f2 when receiving various types of noise such as noise with periodicity and noise with continuously changing frequency such as VVVF cars , there is no complementarity It is determined that the presence of a train detection signal is not considered and the determination that the train is present is held in the track circuit .

  In the present invention, a signal of an FSK wave that is alternately switched at a low cycle from a transmitter to a signal of two types of frequencies with a small frequency separation, with the frequency between the fundamental frequency of the AC electrification section and its higher harmonics as the fundamental frequency. Transmitting to the rail of the track circuit, the receiver separates the train detection signal transmitted to the rail into signals of two kinds of frequencies, and the complementarity test whether the separated signals of two kinds of frequencies are complementary If the two-frequency signals have complementarity, it is determined that there is no train in the track circuit, and when the train detection signal is not received and when the received two-frequency signals are not complementary, the track It can be judged that there is a train on the circuit, and electric vehicle noise can be eliminated, and noise resistance is greatly improved, and when the train is on the track circuit, malfunction due to noise causes the train to be out of line. Dangerous mistakes It is possible to prevent that the work occurs.

  In addition, since it is possible to prevent a malfunction on the dangerous side that does not exist in the train line, there is no need to consider a 100% unbalanced state assuming a one-side rail breakage in a multi-rail track circuit, and the track is more than current. The circuit length can be increased.

  Furthermore, by controlling the reception levels of the two separated signals of the two frequencies so as to fall within the level appropriate region and then examining the complementarity, it is possible to prevent fluctuations in the reception level due to the weather or the like.

  FIG. 1 is a block diagram showing the configuration of the low frequency track circuit device of the present invention. As shown in the figure, the low-frequency track circuit device has a transmitter 3 and a receiver 4 provided in each track circuit AT, BT, CT using a rail 2 on which a train 1 travels. The transmitter 3 is provided on the train advance side of each track circuit AT, BT, CT, and the impedance provided on the train advance side boundary point of each track circuit AT, BT, CT via the matching transformer 5 and the resonance capacitor 6. It is connected to the tertiary coil 8 of the bond 7. The receiver 4 is provided on the train approach side of each track circuit AT, BT, CT, and the impedance provided on the train approach side boundary point of each track circuit AT, BT, CT via the matching transformer 9 and the resonance capacitor 10. It is connected to the tertiary coil 12 of the bond 11.

  As illustrated in the block diagram of FIG. 2, the transmitter 3 includes an FSK wave generation unit 13, an amplification unit 14, and a filter 15. The FSK wave generator 13 generates a frequency f0 between the fundamental frequency 50 Hz or 60 Hz of the AC electrification section and its higher harmonics based on the signal indicating the position of the train 1 that is input via the relay YR, for example, FIG. As shown in the waveform diagram (a), any one of f0 = 30 Hz, f0 = 80 Hz, and f0 = 135 Hz is set as a fundamental frequency, and a frequency f1 = (f0−−) generated at a fundamental frequency f0 and a deviation frequency Δf = ± 2 Hz. 2Hz) and frequency f2 = (f0 + 2Hz) as a carrier frequency and modulated by a low-frequency FSK system with a keying frequency of 2.0 Hz and 1.5 Hz, and a signal and frequency of frequency f1 = (f0-2 Hz) as shown in FIG. A train detection signal that repeats a signal of f2 = (f0 + 2 Hz) alternately at a constant cycle is output. The train detection signal of this low period FSK wave is amplified by the amplifying unit 14 and then output to the matching transformer 5 through the filter 15, and the rail is passed through the resonance circuit composed of the resonance capacitor 6 and the tertiary coil 8 of the impedance bond 7. 2 to send.

  As shown in the block diagram of FIG. 4, the receiver 4 includes two sets of band-pass filters 16 a and 16 b, pulse width testers 17 a and 17 b, and complementarity tester 18. The band-pass filters 16a and 16b have a keying frequency of 2.0 Hz and 1.5 Hz received from the rail 2 via the resonance circuit composed of the resonance capacitor 10 and the tertiary coil 12 of the impedance bond 11 and the matching transformer 9, and a frequency f1 = (f0− 2Hz) and a low-cycle FSK wave train detection signal of frequency f2 = (f0 + 2 Hz) are input and separated into a signal of frequency f1 = (f0-2 Hz) and a signal of frequency f2 = (f0 + 2 Hz). The pulse width testers 17a and 17b test the pulse widths of the separated signal with the frequency f1 = (f0-2 Hz) and the signal with the frequency f2 = (f0 + 2 Hz), and receive the received signal with the frequency f1 and the signal with the frequency f2. Control the level so that it falls within the appropriate level range. The complementarity test unit 18 performs a complementarity test to check whether the signal of frequency f1 = (f0-2 Hz) and the signal of frequency f2 = (f0 + 2 Hz) are alternating and periodic, and the signal of frequency f1 When the signal of frequency f2 has complementarity, it is determined that the train detection signal is received, and a signal indicating no train is output via relays GR and YR.

  Processing when detecting whether or not a train is present on the track circuit BT with this low-frequency track circuit device will be described.

  The transmitter 1 has a keying frequency of 2.0 Hz and 1.5 Hz based on a signal indicating the current position of the train 1 input via the relay YR, a signal of frequency f1 = (f0-2 Hz) and a signal of frequency f2 = (f0 + 2 Hz). Is transmitted to the rail 2 from the train advancing side of the track circuit BT. When the train 1 is not on the track circuit BT, the train detection signal transmitted to the rail 2 is received by the receiver 4. The receiver 4 separates the received signal into signals having a frequency f1 = (f0-2 Hz) and a signal having a frequency f2 = (f0 + 2 Hz) by the bandpass filters 16a and 16b, and pulses of the separated signal having the frequency f1 and the signal having the frequency f2. The relays GR and YR are fraudulent by controlling the reception level of the frequency f1 signal and the frequency f2 signal received by examining the width to fall within the proper level range to prevent the reception level from fluctuating due to the weather. Prevent falling. Complementarity test of whether or not the signal having the frequency f1 = (f0-2 Hz) and the signal having the frequency f2 = (f0 + 2 Hz) whose reception levels are controlled is periodically alternated with the modulation period by the complementation test unit 18. If the signal having the frequency f1 = (f0-2 Hz) and the signal having the frequency f2 = (f0 + 2 Hz) are complementary, it is determined that the train detection signal is received and the coils of the relays GR and YR are excited. The signal indicating that the train is not present is output to the track circuit BT.

  In this state, when the train 1 enters the track circuit BT and the train detection signal transmitted to the rail 2 of the track circuit BT is not received by the receiver 4 due to a wheel short-circuit, the receiver 4 receives the coils of the relays GR and YR. Is de-energized and a signal indicating that the train 1 is on the track circuit BT is output. In this state, as shown in FIG. 5A, there is no periodicity such as wheel arcing when the wheel of the train 1 is short-circuited, and as shown in FIG. When various noises such as certain noises, noises of VVVF vehicles, etc. that change continuously enter the receiver 4, the complementarity test unit 18 of the receiver 4 tests the complementarity, There is either a signal of frequency f1 or a signal of frequency f2 at a timing when there is no signal of f1 = (f0-2 Hz) or a signal of frequency f2 = (f0 + 2 Hz). In such a case, it is determined that there is no complementarity by the complementarity test of the complementarity test unit 18 and it is not considered that there is a signal, and the non-excitation of the coils of the relays GR and YR is held.

  By eliminating electric vehicle noise in this way, noise resistance can be dramatically improved. When the train 1 is present on the track circuit BT, the train 1 is present due to malfunction due to noise. It is possible to prevent a dangerous side malfunction that causes the track circuit BT to be absent.

  In addition, by eliminating the risk of malfunctioning on the dangerous side, it is no longer necessary to consider a 100% unbalanced state assuming that one rail breaks in a multi-rail circuit, and stable operation is ensured so that signal waves are not suppressed during normal use. The reception voltage of the train detection signal can be determined from the surface. In other words, the multi-rail circuit is used in a balanced state that combines the electrical performance of the two right and left rails, but the length of the two left and right rails and the number of insertions such as signal bonds in the middle are different. The balance is lost due to the mounting condition of the wheel rail, and this tolerance is usually 10%. On the other hand, since it is not necessary to consider the 100% unbalanced state that has been considered in the past when one side of the rail is broken, it is sufficient to consider the unbalance rate that is normally 10%. The induced level of the level becomes 1/10, the reception voltage of the train detection signal can be reduced to 1/10, and the track circuit length can be extended more than the current level.

  Also, in the AC electrification section, the power frequency and its higher harmonics flow in the track circuit and become an interference wave of the track circuit device, so it is necessary to set a signal frequency band in the gap of the interference wave. The FSK method in which the signal frequency band is widened compared to the method is not used. However, as in the low-frequency track circuit device of the present invention, the deviation amount of the frequency f1 and the frequency f2 of the FSK wave, the frequency switching period, and the frequency verification method. By making the verification time characteristic appropriate, the signal frequency band can be set in the gap of the interference wave.

It is a block diagram which shows the structure of the low frequency track circuit apparatus of this invention. It is a block diagram which shows the structure of a transmitter. It is a wave form diagram which shows the train detection signal of the low period FSK wave transmitted from a transmitter. It is a block diagram which shows the structure of a receiver. It is a waveform diagram which shows the noise which generate | occur | produces with an electric vehicle.

Explanation of symbols

1; train, 2; rail, 3; transmitter, 4; receiver, 13; FSK wave generator,
14; amplification unit, 15; filter, 16; bandpass filter, 17; pulse width verification unit,
18: Complementarity test part.

Claims (1)

A transmitter and a receiver,
The transmitter modulates by the FSK method using the fundamental frequency in the AC electrification section and the frequency f0 between its higher harmonics as a fundamental frequency, and has two types of frequencies f1 = (f0−Δf) and a frequency with a small frequency separation. F2 = (f0 + Δf) signal is generated alternately with a low cycle FSK wave signal, the train detection signal obtained by power amplification of the generated FSK wave signal is transmitted to the rail,
The receiver has two sets of bandpass filters and a phase correction verification unit,
The two sets of band filters separate the train detection signal transmitted to the rail into signals of two types of frequencies f1 and f2,
The phase correction assay unit performs a complementation assay to determine whether a modulation period and periodically alternately to the two pairs of two separated by band-pass filter of frequencies f1, f2 of the signals, two When the signals of the frequencies f1 and f2 are complementary, it is determined that there is no train in the track circuit, and when the train detection signal is not received, it is determined that there is a train in the track circuit. When various noises such as a certain noise or noise of a VVVF vehicle continuously changing are received and there is either a frequency f1 signal or a frequency f2 signal, it is determined that there is no complementarity and the train A low-frequency track circuit device characterized by holding a determination that there is a train in the track circuit without assuming that there is a detection signal .

Images