JP4731243B2 - Distribution line exploration equipment - Google Patents

Description

  The present invention is a wiring path exploration that correctly determines a wiring path when inspecting and confirming a correspondence on an electrical wiring between a base end of a distribution path such as a distribution board of a building and a terminal end of the distribution path such as an outlet. It relates to the device.

A wiring path that identifies the wiring path by receiving the distribution line carrier signal sent from the transmitter connected to the end of the distribution path such as an outlet with the receiver connected to the base end of the distribution path such as a distribution board Search devices have been proposed in the past (Patent Documents 1 to 3). These specify the wiring path to which the transmitter is connected according to the magnitude of the received signal.
Japanese Patent Laid-Open No. 10-213617 JP-A-10-213618 Japanese Patent Laid-Open No. 10-213620

  When the distribution line carrier signal receiver determines the distribution path based on the magnitude of the received signal, in the wiring path as shown in FIG. 1 or FIG. 2, due to the influence of the configuration and the impedance of the load connected to the wiring path, It may be difficult to specify the wiring path or make an incorrect determination. This will be described in detail below. 1 and 2 show a state where all of the circuit breakers 5a to 5e and 6a to 6e provided in the branch circuits 3a to 3e and 4a to 4e of the distribution boards 1 and 2 are turned on.

  In FIG. 1, when only the circuit breaker 5a is turned on, a current signal (a current signal having a predetermined frequency different from the commercial frequency) transmitted from the transmitter 7 passes through the distribution path 8a and the branch circuit 3a. A closed circuit is formed that returns to the transmitter 7 through the secondary side of the power receiving transformer 9. Therefore, the receiver 10 detects the current signal by the current signal sensor 11a (current transformer, magnetic sensor, etc.). In this case, the magnitude of the current signal detected by the receiver 10 is the same as the magnitude of the current signal transmitted by the transmitter 7.

  When both the circuit breakers 5a and 5d are on, the current signal transmitted from the transmitter 7 is also shunted to the load 12 through the branch circuit 3d and the distribution path 8d. Therefore, the receiver 10 detects the current signal not only by the current signal sensor 11a but also by the current signal sensor 11d. The magnitude of each current signal depends on the impedance ratio between the power receiving transformer 9 and the load 12. In many cases, since the impedance of the power receiving transformer 9 is lower than the impedance of the load 12, most of the current signal flows to the secondary side of the power receiving transformer 9.

  However, depending on conditions such as the impedance of the power receiving transformer 9 being high, the distance from the power receiving transformer 9 being long, the impedance of the line being added, and the impedance of the load 12 being very low, more than half of the current signal sent by the transmitter 7 May flow to the branch circuit 3d and the power distribution path 8d to which the load 12 is connected. In such a case, there is no significant difference in the magnitude of the current signal detected by the current signal sensors 11a and 11d of the receiver 10.

  Therefore, since current signals having substantially the same level or opposite levels are detected in the wiring path 8a (main line) that should be searched and the wiring path 8d (non-main line) that should not be searched, it is difficult to specify the main line. .

  In FIG. 2, when the receiver 10 is connected to the distribution board 2 that is installed relatively close to which the main line is not connected, the impedance of the power receiving transformer 9 is high, the distance from the power receiving transformer 9 is long, and Depending on conditions such as the addition of impedance and the impedance of the load 12 being very low, the wrong wiring path 13a is erroneously determined to be a main line.

(Object of the present invention)
An object of the present invention is to provide a power distribution route searching apparatus that can determine the power distribution route to be searched without error while eliminating the influence of the impedance of the load.

In order to achieve the above object, the present invention receives a transmitter that transmits a modulated current signal at the end of a power distribution path, and receives the current signal transmitted from the transmitter at the base end of the power distribution path by synchronous detection . Having a receiver, detecting the direction of the current signal received by the receiver, and the direction of the current signal received by the receiver being the same as the direction of the current signal at the transmitter, A distribution path exploration device that determines that the distribution path is to be searched, and determines that the current signal is in the opposite direction when the direction of the current signal is opposite , wherein the transmitter modulates the distribution path. The waveform of the current signal to be transmitted is assumed to be a change point by modulation at a predetermined point, and the receiver receives from the waveform of the current signal received by synchronous detection corresponding to the change point by modulation on the transmission side. The reference point on the transmission side is calculated and the change on the transmission side is calculated. The phase difference of the reference point on the receiving side and the phase difference at the receiving side is used as the amount of phase correction, the phase of the sine wave used for synchronous detection is corrected, and the current signal is again generated by synchronous detection using the phase-corrected sine wave. Receiving and detecting the direction of the current signal from the phase of the current signal received again with respect to the reference point .

  ADVANTAGE OF THE INVENTION According to this invention, the influence of the impedance of a load can be excluded and the distribution path which should be investigated can be determined without an error.

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

  As shown in FIGS. 1 and 2, a distribution line exploration device according to an embodiment of the present invention includes a transmitter 7 connected to the end of a distribution line such as an outlet, and branch circuits 3 a to 3 b of the distribution board 1. A receiver 10 connected to the base end of the distribution path such as 3e, and when the receiver 10 receives the current signal of the distribution line carrier signal sent from the transmitter 7 and determines the wiring path, The wiring path is determined without error by specifying the direction.

  FIG. 3 shows a current signal waveform and phase when there is no phase rotation of the current signal in the state of FIG. 1 or FIG. The direction of the current signal is opposite between the main line (distribution path 8a in FIG. 1) and the non-main line (distribution path 8d in FIG. 1). In other words, there is a difference of 180 degrees when the phase of the current signal is compared, so it is easy to detect the phase of the current signal that the main line has by comparing the phases of one main line and multiple non-main lines relatively. It becomes.

  However, in an actual distribution line, an electric device (load) is connected to the distribution line, and a current signal is generated as shown in FIG. 4 due to the influence of the distribution line and the impedance (L: induction component, C: capacitance component) of the electric device. The phase of can rotate and change up to ± 90 degrees. For this reason, there is a case where the main line and the non-main line cannot be determined only by comparing the difference between the current signal reception phases.

  In this embodiment, the transmitter 7 shown in FIG. 5 and the receiver 10 shown in FIG. 6 are used to send out a specific current signal, which will be described later, from the transmitter 7 installed on the outlet side, and to the distribution board side. The installed receiver 10 detects the phase of the current signal for each distribution path. The phase of the current signal detected by the receiver 10 is compared with a reference phase calculated from the specific current signal transmitted from the transmitter 7, and as shown in FIG. The phases of the current signal regions are distinguished. In this way, the main line and the non-main line are determined.

  The reference phase may be provided, for example, at the zero-cross point of the commercial frequency voltage (50 Hz or 60 Hz). However, this may be affected by errors due to the hardware of the transmitter 7 and the receiver 10, and this is avoided. Therefore, it is calculated from a specific signal waveform.

  In FIG. 5, 14 is a carrier signal transmission circuit, 15 is a commercial frequency synchronization circuit, 16 is a power supply circuit, and 17 is a CPU. The carrier signal transmission circuit 14, the commercial frequency synchronization circuit 15, and the power supply circuit 16 are connected to a power distribution path.

  In FIG. 6, 18 is a band-pass filter, 19 is an amplifier, 20 is an A / D converter, 21 is a CPU, 22 is a commercial frequency synchronization circuit, and 23 is a power supply circuit. The band pass filter 18 is connected to the current signal sensors 11a to 11e, and the commercial frequency synchronization circuit 22 and the power supply circuit 23 are connected to the power distribution path.

  Details of the procedure are shown in FIG. 8 (in the case of the main line) and FIG. 9 (in the case of the non-main line).

  In FIG. 8, the transmitter 7 controls the carrier signal transmission circuit 14 at a programmed timing to form the current signal shown in FIG. 8A and to send it superimposed on the power distribution path. The waveform of the output current signal is formed by a value written as data on the program. The output timing is determined by calculation inside the CPU 17 with the commercial frequency zero cross point obtained from the commercial frequency synchronization circuit 15 as a reference.

  The point A in the figure is the point where the phase is reversed. This point A is a zero cross point of the commercial frequency voltage. The current signal has a higher frequency than the commercial frequency, and the phase is inverted by 180 ° at the phase inversion point A as shown in FIG. That is, it is a phase modulation signal (PSK).

  In the case of the main line, the current signal transmitted from the transmitter 7 is detected by the current signal sensor 11a of the receiver 10 shown in FIG. 6, and passes through the band-pass filter 18, the amplifier 19 and the A / D converter 20. Input to the CPU 21, the CPU 21 performs reception processing.

  The CPU 21 performs synchronous detection by multiplying the received current signal by the sine wave (sin θ) of FIG. As a result of the calculation, the waveform of FIG. 8C is obtained.

  The waveform of FIG. 8C is moving averaged as digital processing, and as a result, the waveform of FIG. 8D is obtained.

  In the waveform of FIG. 8D, a change point from positive to negative or from negative to positive is determined as a reference point B.

  The reference point B is a point where the phase reversal point A is shifted by the moving average process. When the moving average of one period of the current signal is ½ period, when the moving average of two periods is taken, the reference point B is one period. Thus, since the point deviates from the phase inversion point A by a fixed amount, the phase of the signal waveform with respect to the reference point B can be calculated.

  Here, when there is no phase difference between the received current signal and the sine wave (sin θ) of FIG. 8B, the waveform obtained in FIG. 8D is a waveform having an amplitude of ± 0.5. As the phase difference increases, the amplitude decreases, and when the phase difference is ± 90 °, the amplitude becomes zero. Therefore, the received current signal waveform is also multiplied by a sine wave (cos θ) that is 90 ° out of phase with the received current signal to obtain the waveform indicated by the dotted line in FIG. The waveform of FIG. 8D is obtained.

  In FIG. 8D, the reference point B can be obtained from any of the results obtained by multiplying sin θ and cos θ. The reference point B is a point on the reception side corresponding to the phase inversion point A on the transmission side.

  Based on the reference point B obtained by the above procedure, phase correction is performed on the sine wave multiplied in FIG. 8B to obtain the phase-corrected sine wave in FIG. C is a phase correction amount. The waveform of FIG. 8 (f) obtained by multiplying this by the received current signal is further subjected to moving average to obtain the waveform of FIG. 8 (g).

In the waveform of FIG. 8 (g), if the point back from the reference point B, for example by one cycle of the signal, is positive, it is a signal received on the main line, and if it is negative, it is determined that the signal is received on the non-main line. To do.
In FIG. 8G, since it is positive at a point D that goes back from the reference point B, it is determined as a main line.

  For the signal received on the non-main line, the above procedure is performed to finally obtain the waveform of FIG.

  This is negative at a point D that goes back from the reference point B, so it is determined as a non-main line.

  In the current signals received from the plurality of current signal sensors 11a to 11e, the phases may be different from each other, and the respective reference points B are calculated for all, and it is determined whether the current line is a main line or a non-main line. . The degree of the point D that goes back to the reference point B depends on how much the moving average is performed. Points D in FIGS. 8 and 9 show the case where the moving averaging process is performed for 1.5 cycles. When the moving averaging process is set to one cycle or less, the calculation result becomes unstable (takes a transient numerical value). Therefore, a stable point of one cycle or more is preferable.

  In this way, when current signals having substantially the same level are detected by determining the phases (current directions) of all current signals, the receiver is connected to the distribution board 2 to which the main line is not connected as shown in FIG. It is possible to prevent erroneous determination even when 10 is connected.

  In the above embodiment, the phase modulation signal whose phase is inverted at the zero cross point is used as the current signal. However, any signal having an obvious change point may be used. For example, a frequency modulation signal (FSK) or an amplitude phase modulation signal (QAM) may be used.

It is a wiring diagram which shows an example of the connection state of the power distribution circuit investigation apparatus which is an Example of this invention, and a power distribution circuit. It is a wiring diagram which shows the other example of the connection state of the distribution path search apparatus which is an Example of this invention, and a distribution path. It is a figure which shows the waveform and phase of an electric current signal when there is no phase rotation. It is a figure which shows the waveform and phase of an electric current signal in case there exists phase rotation. It is a block diagram which shows the circuit structural example of the transmitter in the Example of this invention. It is a block diagram which shows the circuit structural example of the receiver in the Example of this invention. It is a figure which shows the current signal area | region of a main line | wire and a non-main line | wire in case there exists phase rotation. It is a figure which shows the procedure at the time of the main line determination in the Example of this invention. It is a figure which shows the procedure at the time of the non-main line determination in the Example of this invention.

Explanation of symbols

1, 2 Distribution board 3a-3e, 4a-4e Branch circuit 5a-5e, 6a-6e Breaker 7 Transmitter 8a, 8d, 13d Power distribution path 9 Power receiving transformer 10 Receiver 11a-11e Current signal sensor 12 Load

Claims (2)

It has a transmitter for transmitting a current signal modulated at the end of the distribution channel, and a receiver for receiving a synchronous detection current signal transmitted from the transmitter at the proximal end of the distribution channel, at the receiver The direction of the received current signal is detected, and when the direction of the current signal received by the receiver is the same as the direction of the current signal at the transmitter, it is determined that the distribution path is to be explored. A distribution path exploration device that determines that the current signal direction is opposite and that the distribution path should not be explored,
The transmitter modulates and sends a waveform of a current signal to be transmitted, and a predetermined point becomes a change point by the modulation,
The receiver calculates a reference point on the reception side corresponding to the change point by the modulation on the transmission side from the waveform of the current signal received by synchronous detection, and changes the change point by the modulation on the transmission side and the reception side. The phase shift of the reference point is used as a phase correction amount, the phase of the sine wave used for synchronous detection is corrected, the current signal is received again by synchronous detection using the phase corrected sine wave, A distribution path exploration device that detects the direction of the current signal from the phase of the current signal received again . 2. The distribution path exploration device according to claim 1 , wherein when the transmitter modulates the current signal by phase modulation, the change point by the modulation is a point where the phase is inverted .

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