JP2836974B2 - Pantograph disconnection measurement method and its processing circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the disconnection of a railroad in an AC electrified section of an electric railway for investigating the characteristics of overhead lines and pantographs in a running state.

[0002]

2. Description of the Related Art As a method of measuring a pantograph line disconnection in an AC section, as shown in FIG. 5, two capacitors are connected in series to a pantograph to divide the potential of the pantograph and to connect a capacitor connected to the ground potential side. A method of measuring the potential difference 16 at both ends has been put to practical use. This method is described in the following document. As shown in FIG. 6, the signal waveform 16 measured by this method becomes a step-like waveform when the pantograph is disconnected, as shown in FIG. It was a circuit to detect. This method has been able to accurately measure the pantograph's line separation.

[Problems to be solved by the invention]

[0003] However, with the recent stabilization of power equipment, the voltage of the overhead wire has come to include not only a basic sine wave but also various harmonics. Therefore, the potential difference between both ends of the capacitor also fluctuates due to harmonics of the overhead wire voltage,
It has become difficult to distinguish from changes at the time of disconnection.

[0004]

According to the present invention, a capacitor and a resistor are connected in series to a pantograph for measurement, and a potential difference between both ends of the resistor is measured to reduce the disconnection of the pantograph. The main feature is to detect. FIG. 1 shows the configuration of this measuring method.

[0005]

The current waveform of charging / discharging of the capacitor 3 substantially appears in the potential difference 13 across the resistor 4 in FIG. When the pantograph 2 is on the trolley wire 1, the potential of the pantograph changes in accordance with the potential of the overhead wire (potential of the trolley wire), and the current whose phase is advanced by about 90 ° with respect to the change in the overhead wire voltage. Flows through the capacitor 3 and the resistor 4. However, when the pantograph is disconnected, the current is a combination of zero and a pulsed charge / discharge. By processing the signal of the potential difference 13 across the resistor 4, the current is not affected by the harmonics of the overhead wire voltage. In this way, the pantograph can detect the line separation.

[0006]

FIG. 1 is a block diagram of the present invention. The pantograph 2 is attached to the vehicle, and the trolley wire 1 and the pantograph 2 are arriving during low-speed running. However, the pantograph 2 moves away from the trolley wire 1 as the vehicle runs at a higher speed.

[0007] A capacitor 3 and a low resistor 4 are connected in series to the pantograph 2 and grounded. A signal proportional to the magnitude of the current flowing through the capacitor is output from both ends of the low resistor.

FIG. 2 is an example of a waveform of a current flowing through a capacitor. When the pantograph arrives at the trolley wire, the potential of the pantograph changes in accordance with the potential of the overhead wire (the potential of the trolley wire), and the phase is approximately
90 ° advanced current flows. However, when the pantograph is disconnected, the pantograph retains the potential immediately before the disconnection, but the potential of the overhead wire changes. The potential of the pantograph approaches the potential of the overhead wire. Therefore, when the separation between the pantograph and the trolley wire is small, the pulse current is generated at a short interval, and when the separation is large, the interval between the pulse currents becomes large, and the current becomes zero during that time.

FIG. 3 is a circuit for processing a signal of a potential difference between both ends of a low resistor. The following two processes are simultaneously performed on the output signal 13 at both ends of the low resistor. One system is to detect small separation lines where the separation between the pantograph and the trolley line is small.
The other system detects a large separation where the separation between the pantograph and the trolley wire is large. FIG. 4 shows a waveform example in the signal processing process of two systems.

The detection of a small disconnection is to extract the waveform of the pulse charging / discharging train. After removing the fluctuations of the fundamental and harmonics of the overhead wire through the high-pass filter 7, the signal is rectified and the comparator 9 generates a disconnection signal.

The detection of a large detachment is to take out a waveform having zero current. First, only the vicinity of zero of the measurement signal is detected by the window comparator 10. Next, in order to remove the zero crossing of the fundamental wave of the alternating current, only the continuous signal of the zero signal is taken out through the low-pass filter 11, and then the signal is separated by the comparator 12 into a disconnection signal.

The final OR signal 14 is obtained by obtaining the logical sum of the respective signals subjected to the two systems of processing by the OR circuit 12.

[0013]

According to the present invention, the pantograph disconnection in the AC electrified section can be accurately measured without being affected by harmonics of the overhead line voltage, so that it can be used for pantograph characteristic investigation, finding an abnormal location of the overhead line, and the like.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of the present invention.

FIG. 2 is an example of an output waveform of a low resistor 4 in FIG.

FIG. 3 is a block diagram showing a configuration of a processing device 6 in FIG. 1;

FIG. 4 is an example of a signal processing waveform in the processing device 6 of FIG. 1;

FIG. 5 is an overall configuration diagram of a conventional capacitance partial pressure type disconnection measurement method.

FIG. 6 is a waveform example of a measurement signal 16 obtained by the capacitance voltage dividing method of FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 trolley wire 2 pantograph 3 capacitor 4 low resistor 5 ground 6 processing device 7 high-pass filter 8 rectifier 9 comparator 10 window comparator 11 low-pass filter 12 OR circuit 13 low-potential signal at both ends of low resistor 14 disconnection signal 15 capacitor 16 capacitor both ends Potential difference signal 17 Processor 18 Disconnection signal

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-131705 (JP, A) JP-A-53-96881 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B60L 5/00-5/42 G01B 7/00

Claims (2)

(57) [Claims] 1. A trolley wire and pantograph in electric railway AC electrified section is a method of detecting that you mechanically separated, connect a capacitor and a resistor in series with the measuring pantograph, the processing circuitry at both ends of the resistor Connect the condenser
The pulse signal during pulse charging / discharging of the sensor is
Detects by filter processing and zero-passes the zero signal when there is no current.
Detected by filter processing
A pan characterized by detecting that the graph is disconnected.
Tagograph line measurement. 2. A trolley line and a path in an AC electrified section of an electric railway.
Pantgra that detects when the graph is mechanically separated
In a divergence measuring device, it is connected in series with the pantograph for measurement.
Connect the connected capacitor and resistor to both ends of the resistor.
Pulse signal at the time of pulse charge / discharge of the capacitor
And a zero-pass filter when there is no current.
It is equipped with a low-pass filter that emits in parallel.
Pantograph line break measurement device.