JP5354568B2 - System identification device - Google Patents

Description

The present invention relates to an apparatus for exploring whether a higher-level device / wiring and a lower-level device / wiring of a plurality of distribution systems branched from the same transformer are in the same system.

In an existing distribution system, it may be necessary to investigate which lower-level equipment is connected to which higher-level equipment.

As devices used for such exploration, devices such as Patent Literature 1 to Patent Literature 3 are known.

In Patent Document 1, a cyclic leakage current is generated between the voltage line of the terminal circuit and the ground, and an attempt is made to identify the circuit system based on whether or not the current can be detected by an upper circuit. Since the earth leakage current is generated in the electric circuit and the leakage current is detected in the upper circuit, the electric circuit line connecting the terminal side device must be the voltage side line, and it is connected to the earth side wire. Must be reconnected to the voltage side wire.

Patent document 2 injects a high frequency signal between the lines of the terminal electric circuit, detects the signal phase at two points across the branch part of the upper circuit, and tries to identify the electric circuit system based on whether the phases are the same. However, it is necessary to connect the device on the end side between the two wires of the electric circuit, and when connecting the device between the two wires of the lower wiring, it is easy to operate and safe like an outlet. There is no problem as long as the connector is considered, but if the device to be explored is like a breaker, it must be connected to two live parts of the terminals at each pole of the breaker. Since two live parts are located at a close distance, there is a possibility of accidents such as accidental shorting between terminals of different polarity. In addition, the breaker terminal cover usually has a small hole for voltage detection, but the old type breaker may have only one small hole. The work must be done with the live part protective cover removed, increasing the risk of shorting between the different terminals.

In Patent Document 3, two types of signals, high frequency and low frequency, are injected between one line of the terminal circuit and the ground, or between the lines of the circuit, and in the upper circuit, rough exploration is at high frequency, and final exploration is The system is intended to identify the system using low frequency, but there is an advantage that the connection of the equipment on the terminal circuit side can be between one line and the ground or between the two lines, but the circuit network is large and the terminal circuit is large. The system configuration and measurement procedure are complicated because the system is assumed to be located when the distance between the equipment installed on the side and the equipment installed on the upper side of the trunk line is long. In reality, it is often necessary to search for lower and upper systems at relatively close distances, as in the correspondence relationship between multiple watt-hour meters and multiple switches directly below. A simple and inexpensive measuring method is desired.
JP 63-33669 A Japanese Patent Laid-Open No. 7-113834 JP 2006-184246 A

Therefore, according to the present invention, the terminal side device is connected between one line of the electric circuit and the ground, so that short circuit between different terminals is unlikely to occur, and one line of the electric circuit connecting the device may be a voltage side line or a ground side line. Therefore, it is an object of the present invention to provide a determination apparatus for an electric circuit system that can be determined with a simple and reliable apparatus configuration and measurement method without the need for connection replacement.

Claim 1, in the apparatus for determining the upstream and downstream connection system of a plurality of distribution system connecting the first terminal of the secondary winding in the earth the transformer on the load side, is connected to any system on the upstream side The circuit A includes a circuit A including a means for determining a zero-phase current and a circuit B connected between one terminal of the wiring and the ground in an arbitrary downstream system. The circuit B includes one terminal of the wiring and the ground. Including voltage detection determination means, impedance, voltage generation means, and connection switching means connected between, when the voltage detection determination means detects the distribution voltage of the system, the impedance is switched between one terminal of the wiring and the ground while connecting means selects, when no detected connects the voltage generating means connected switching means selects the current due to the circuit a is connected to the impedance or voltage generating means in the circuit B Inspection Wiring or equipment lines were installed system and circuit B for wiring or equipment installed circuit A when is obtained by providing a system discriminating apparatus and outputs a determination result to be identical.

According to a second aspect of the present invention, the determination element that the zero-phase current of the circuit A is caused by the connection of impedance or voltage generating means includes the magnitude of the current. A discrimination device is provided.

According to a third aspect of the present invention, the impedance of the circuit B is a resistor, and the determination circuit of the circuit A is based on the voltage detected by the voltage detection determination means of the circuit B or the phase of the voltage generated by the voltage generation means. The current of the resistance is detected from the detected current, and it is determined that the magnitude of the current due to the resistance is due to the impedance of the circuit B or the connection of the voltage generating means. A system discrimination device is provided.

According to a fourth aspect of the present invention, the determination element that the zero-phase current of the circuit A is due to the connection of impedance or voltage generation means includes the sign of the encoded signal, and the impedance or voltage generation means is encoded control According to another aspect of the present invention, there is provided a system discriminating apparatus according to claim 1, wherein encoding control is performed by means.

According to the present invention, in the device for exploring the upper and lower systems of the plurality of distribution systems on the load side of the transformer with one terminal of the secondary winding grounded to the ground, the circuit on the end side is 1 of the electric circuit. The connection between the wire and the ground is less likely to cause short-circuits between different terminals, and one line of the electrical circuit connecting the device may be a voltage side wire or a ground side wire, and once connected, there is no need to change the connection. It is possible to provide a determination device for an electric circuit system that is simple and reliable in configuration and measurement method.

Next, the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram of a first embodiment of the present invention. In the figure, reference numeral 1 denotes a transformer, one end of the secondary winding is connected to the ground, and the secondary winding branches off into a plurality of system electric circuits 201, 202, 203. 301, 302, 303,... Are integrated watt-hour meters provided on the upper side of each system, and breakers 401, 402, 403,. .. And the breakers 401, 402, 403... Correspond to each system, but the connection status of the wiring connection between them including the arrangement is unknown, and the integrated power Suppose you want to determine the correspondence between a meter and a breaker.

Reference numerals 5 and 6 are system discriminating devices according to the present invention, 5 is a circuit A for clamping the upper wiring of the system, 6 is a circuit B connected to the lower side of the system, and circuit A is a zero-phase current of the system wiring. Current detector 501, zero-phase current detection circuit 502, and determination circuit 503. The circuit B is connected between a lead wire 601 connected to one of the breaker terminals, a lead wire 602 connected to the ground terminal 7 such as a WHM or a metal box containing the breaker, and lead wires 601 and 602. Voltage detection determination means 603, impedance 604, voltage generation means 605, and connection switching means 606 that selectively switches the connection between impedance 604 and voltage generation means 605 based on the detection result of voltage detection determination means 603.

Note that the lead wire 601 is configured to be connected to one of a plurality of terminals of the breaker in the form of a contact rod from a hole for electric detection opened in a charging portion cover of the breaker terminal portion.

Next, the operation of the apparatus of the present invention will be described. First, the zero-phase current transformer 501 of the circuit A is attached to an arbitrary system wire on the integrated watt-hour meter side. After that, when the lead wires 601 and 602 of the circuit B are connected to one of the breaker terminals on the lower breaker side and 602 is connected to the ground terminal, the voltage detection determination means 603 is connected to the breaker terminal and the lead wire to which the lead wire 601 is connected. The voltage between the grounds connected to 602 is detected and determined. In FIG. 1, since the lead wire 601 is connected to the terminal on the voltage (L) side line, the voltage detection determining means 603 measures the terminal voltage on the secondary side of the transformer, so it is determined that there is a voltage, and the switching connecting means 606 Is switched to the impedance 604 side.

When the impedance 604 is connected between the lead wires 601 and 602, a current Iz corresponding to the impedance 604 flows from the L-side voltage line to the ground. In FIG. 1, since the system wiring in which the zero-phase current transformer 501 is installed is the same as the system to which the lead wire 601 is connected, the zero-phase current transformer 501 and the detection circuit 502 detect the current Iz, and the judgment circuit 503 The breaker 401 connected to the line 601 is on the same system as the integrated watt-hour meter 301 of the system to which the zero-phase current transformer 501 is attached and is determined to have a corresponding relationship, and the result is output by voice or visual display. Note that the output may be included in the determination circuit 503, or a means for receiving and displaying the output of 503 may be provided separately.

When the voltage detection determination unit 603 does not detect a corresponding voltage between the lead wires 601 and 602, the connection switching unit 606 switches to the voltage generation unit 605 side. In this case, since the terminal of the breaker to which the lead wire 601 is connected is the ground (N) side wire, it is as shown in FIG. 2 as a whole, and the system ground (N) side wire, transformer ground wire, ground, breaker side The current Ig from the voltage generating means 605 flows through the system using the ground of the current as a path. When the zero-phase current transformer 501 and the detection circuit 502 detect Ig, the circuit A determines that the breaker 401 is connected to the integrated watthour meter 301 and outputs the result.

If the breaker to which the lead wire 601 is connected is not a system of the integrated power amount system 301, the zero-phase current transformer 501 does not detect the above-mentioned Iz and Ig, so that the circuit A does not output that the systems are the same. In that case, the connection of the lead wire 601 is sequentially reconnected to the breakers 402, 403, or the zero-phase current transformer 501 of the circuit A is 302, 303, 304,. When the output is output, it is possible to determine which of the integrated watt-hour meters and which of the breakers are on the same system.

In the above description, when there is a ground fault detection device such as an existing earth leakage relay or earth leakage breaker above the breaker 401, the magnitude of Iz or Ig needs to be less than the sensitivity current of the ground fault detection device. It is. For example, in the case of home use, the rated sensitivity current of the earth leakage circuit breaker is generally 30 mA, so that the rated inoperative current is preferably less than 15 mA. Further, there is a case where a dark leakage current has already flowed before the device is connected due to the earth capacitance 9 of the electric circuit 201 shown in FIG. When there is a capacity 8, 10,..., Iz flowing through the impedance 604 returns from the ground to the N of the transformer 1 and the ground capacitance 8, 10,.・ Branch the path that flows to N of the transformer through the earth side wire. In addition, Ig in FIG. 2 has the same influence. Furthermore, there may be other noise in the leakage current, which may limit the determination of the determination circuit 503. However, the following measures can be considered.

First, considering that there is a leakage breaker above the breaker 401, the specifications of the impedance 604 and voltage generation means 605 are set so that Iz and Ig are almost the same, and some errors are expected. This is a method of setting a current threshold for determination by the determination circuit 503. When each system load of the integrated watt-hour meter in FIG. 1 is a general household,
Normally, the ground resistance on the N pole side of the transformer 1 is 10 Ω or less and the ground resistance of the terminal 7 is 500 Ω or less. Therefore, if Iz and Ig are set to about 10 mA, the impedance 604 is set to a power supply voltage of 100V. Although it is about 10 kΩ, if the ground resistance is 10Ω + 500Ω or less, Iz hardly changes. Further, if the voltage generating means 605 is a constant current source, the output power when 10 mA is passed through the maximum ground resistance of 10Ω + 500Ω can be simply configured because only 510Ω × 10 mA × 10 mA = 0.05 W is sufficient.

The influence of the ground capacitances 8, 9,... In FIGS. As described above, when the load of 201, 202, 203... Is normally used at home and the circuit is such that an earth leakage breaker with a rated sensitivity current of 30 mA is installed, it depends on the ground capacitance. It is considered that the leakage current is at most less than the above-mentioned rated inoperative sensitivity current of 15 mA. Since it is generally several mA or less, the impedance of the ground capacitance is considered to be several tens of kΩ or more. In FIG. 1, the current flowing through the impedance 604 flows from the lead wire 602 to the ground terminal 7, the path flowing from the ground to the ground terminal N of the transformer 1, the lead wire 602 to the ground terminal 7, the ground capacitance 8, and the ground side line of the electric circuit 201. A path that flows to the ground terminal N of the transformer 1, a capacitance to the ground 10, and a path that flows to the ground terminal N of the transformer 1 through the ground side line of the electric circuit 202 (hereinafter, the same applies to the electric circuits 203 and 204). As described above, the resistance when the path is 10Ω + 500Ω and the impedance when the path is the ground capacitance 8, 10,... ... Does not flow on the side. Therefore, if the detection threshold of the determination circuit is set to be slightly lower than 10 mA, Iz can be detected in the electric circuit 201 of FIG. 1, and Iz can be detected even if the electric circuit 202 includes a dark leakage current that is routed to the ground capacitance 11. Therefore, no erroneous detection is made (the same applies to the electric circuits 203, 204,...).

In the case of FIG. 2, the current Ig flowing by the voltage generating means 605 also flows from the lead wire 601 through the ground side line of the electric circuit 201 and from the ground capacitance 8 to the N side terminal of the transformer 1 via the ground. The current that flows to the ground side line of the electric circuit 201 is also connected to the path from the N terminal of the transformer 1 via the ground, the ground side line of the electric circuit 202, and the ground capacitance 10 to the ground. However, as in the explanation of FIG. 1, the resistance with the ground as a route is about 510Ω at the maximum, and the capacitance to the ground is 8, Since the impedance of 10... Is several tens of kΩ, there is almost no current flowing through the ground capacitances 8 and 10, Ig can be detected in the circuit 201, and leakage due to the ground capacitance 10 can be detected in the circuit 202. Even if the leakage current is included, it does not reach Ig, so that it is not erroneously detected (the same applies to the electric circuits 203 and 204). Therefore, in most cases, if the values of Iz and Ig are made substantially the same, the current threshold value of the determination circuit is selected to be slightly lower than Iz and Ig, and the value of Iz or Ig is set appropriately, A system can be determined without erroneous determination.

However, if the impedance of the ground capacitance of each circuit is lower than the above explanation, for example, if there is a leakage current of about 10 mA due to the ground capacitance for each circuit, the above method alone will cause the following error. It becomes a judgment.

First, in the case of FIG. 1, the determination current threshold of the determination circuit is set to a value slightly lower than 10 mA according to the above method, but the leakage current due to the ground capacitance for each electric circuit is about 10 mA. In FIG. 1, even if Iz due to the impedance 604 is set to 10 mA, the leakage currents of the electric circuits 201, 202... Are about 10 mA or more, and the electric circuit 201 to which the impedance 604 is connected cannot be specified.

Next, in the case of FIG. 2, when the generated voltage frequency of the voltage generating means 605 is the same as the frequency of the electric circuit, depending on the phase of the generated voltage, it varies depending on the relationship with the phase of the leakage current due to the ground capacitance described above. In some cases, the current detected by the flow device 501 is smaller than Ig. In this case, the electric circuit to which the voltage generator 605 is connected cannot be specified.

In this case, the impedance 604 in FIG. 1 is the impedance of the resistance, the phase data of the voltage detected by the voltage detection determination means 603 in FIG. 1 and the measured current data, and the generated voltage frequency of the voltage generation means 605 in FIG. Based on the phase data of the generated voltage and the current data obtained by filtering and extracting only the generated voltage frequency component in the measured current data, the determination circuit 503 determines only the current flowing through the resistance from the current data. The threshold value may be set to a current slightly lower than the above-described Iz or Ig based on the detected resistance current. By doing so, there is no misjudgment because only the magnitudes of Iz in FIG. 1 and Ig in FIG. 2 can be detected. In the case of FIG. 2, the above-described filtering process may be omitted if the generated frequency of the voltage generating means 605 is set to 1 / integer or multiple of the frequency of the circuit voltage.

Here, a method for extracting a current only for resistance based on voltage phase data will be briefly described. FIG. 3 is a conceptual diagram of the relationship between voltage and current when a resistor and a capacitor are connected to an AC voltage. The resistance divided current Ir is in phase with the voltage v and the voltage divided current Ic is the voltage. The phase is advanced by 90 degrees from v, and Io is a combined current of Ir and Ic, and is advanced by a phase angle θ from the voltage v. Therefore, if the voltage phase is known, Ir can be obtained by measuring the phase difference from the current Io and calculating Io × cos θ.

Also, Ir in FIG. 3 can be obtained by the method in FIG. 4A is the circuit voltage v, FIG. 4B is the current Ir flowing through the resistance, and FIG. 4D is the current Ic flowing through the capacitance. Here, the waveforms of the currents Ir and Ic are inverted according to the phase of each half wave of the voltage v. That is, since the voltage in the section from (a) to b is positive, the Ir and Ic waveforms remain as they are, and in the section from (b) to b, the voltage is-, so Ir and Ic. Invert the waveform. As a result, if Ir becomes (c) and Ic becomes (e) and averages, Ir becomes a positive value and Ic becomes zero, so Ic can be canceled.

In the case of FIG. 1, if the impedance 604 is a resistance, Iz becomes a current in phase with the circuit voltage. Therefore, the current detected by the current transformer 501 is obtained based on the circuit voltage data detected by the voltage detection means 603. If only Iz is extracted by the method of FIG. 3 or FIG. 4, there will be no erroneous determination in the case of FIG.

Next, in the relationship between the frequency of the voltage generated by the voltage generating means in FIG. 2 and the frequency of the dark leakage current flowing through the ground capacitance due to the commercial circuit voltage, the frequency of the voltage generated by the voltage generating means is the frequency of the dark leakage current. A case will be described in which the method of FIG. 4 is applied when the frequency of the integral fraction of 1 or the frequency of the voltage generated by the voltage generating means is an integral multiple of the frequency of the dark leakage current. 5A and 5B are explanatory diagrams when the method of FIG. 4 is applied when the frequency of the voltage v is (b) half the frequency of the current I. The current I remains unchanged in the interval from a to b of the waveform of the voltage v, and the current I is inverted in the interval from b to c, and the current becomes a waveform as shown in (c). The magnitude of the current I is the voltage regardless of the phase. If the average value of one cycle is taken, it can be made zero.

Similarly, in FIG. 6, when the method of FIG. 4 is applied when (a) the frequency of the voltage v is (b) twice the frequency of the current I, the current I remains as it is in the interval from a to b of the voltage v. In the period from b to c, if the current I is inverted, the waveform becomes as shown in (c), and the magnitude of the current I can be made zero by taking the average value in the period of two cycles of the voltage regardless of the phase. That is, if the frequency of the voltage generated by the voltage generating means 605 in FIG. 2 is set to 1 / integer or multiple of the frequency of the circuit voltage as described above, the influence of the dark current flowing to the ground capacitance due to the circuit voltage is reduced to zero. Since only the current Ig by the voltage generating means 605 can be determined, erroneous determination due to the dark leakage current in the electric circuit is eliminated.

When the integrated watt-hour meters 301, 302... And the breakers 401, 402... Are in the same box, etc., the 5 circuits A and 6 circuits B are configured in the same housing. What is necessary is just to extend the current transformer 501 and the lead wires 601 and 602 by the required length from the housing. By doing so, the determination circuit 503 can easily obtain the voltage phase data of the voltage detection determination device 603 and the voltage generation means 605, and can perform the arithmetic processing as shown in FIGS. When the circuit A and the circuit B have to be configured in different cases, the phase timing between the voltage detection determination means and the voltage generation means is determined by a wired signal or a wireless signal (a, b, in FIGS. 4 to 6). If c) is transmitted from the circuit B to the circuit A by a pulse signal or the like, the arithmetic processing can be performed by the circuit A.

As another method, the impedance 604 is made variable by the encoding control means 607 as shown in FIGS. 7A, 7B and 7C, and Iz is intermittently changed or changed in an appropriate pattern as shown in FIG. It may be encoded, and code consistency may be added to the determination condition of the determination means 503. The voltage generated by the voltage generation means 605 is also configured as shown in FIG. 9 so that Ig is changed by the encoding control means 608 as shown in FIG. 9 and the sign consistency of the change is added to the determination condition of the determination means 503. May be.

By doing so, even when the ground leakage current is large, it is possible to easily determine whether the current detected by the current transformer 501 is a ground leakage current or a current due to connection of the circuit B.

The system exploration device as described above only needs to contact one terminal at the breaker on the lower side, so even if the old equipment has only one small hole for detecting the voltage on the terminal cover of the breaker, the terminal cover must be removed. The system can be discriminated without disconnecting it, and it is safe with no possibility of causing an accident such as a short circuit during measurement. Moreover, since the voltage between the grounds is measured and the connection between the impedance and the voltage generating means is switched, it is necessary to change the connection of the lead wire 601 to the voltage side wire even if the wire connected to the lead wire 601 is on the ground wire side. There is no. The system can be identified even when there is a mistake in the wiring of the small holes L and N for detecting electric power, and the terminal to which the lead wire 601 is connected is on the N side. In addition, the measurement method is easy and the system can be reliably identified.

The present invention can be used not only for searching for the correspondence relationship between the integrated watt-hour meter and the breaker, but also for searching for systems such as lower order breakers and outlets.

The figure which shows use and a structure of the apparatus of this invention. The figure which shows use and a structure of the apparatus of this invention. Explanatory drawing of the method of detecting resistance divided current Ir from the combined current of resistance divided current Ir and capacitive divided current Ic Same as above FIG. 4 is an explanatory diagram that can cancel the influence of current when the frequency of the voltage is 1 / integer of the frequency of the current. FIG. 4 is an explanatory diagram that can cancel the influence of current when the voltage frequency is an integral multiple of the current frequency. An example in which a sign control means is provided for impedance. The figure which shows an example of the change pattern of an electric current. An example in which a sign control means is provided in the voltage generating means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transformer 201-204 System wiring 301-304 Integrated watt-hour meter 401-404 Breaker 5 Circuit A
501 Zero-phase current transformer 502 Detection circuit 503 Determination circuit 6 Circuit B
601 602 Lead wire 603 Voltage detection determination circuit 604 Impedance 605 Voltage generation means 606 Connection switching means 607 Sign control means 608 Sign control means 7 Ground terminal

Claims (4)

Detects zero-phase current connected to any upstream system in a device that discriminates upstream and downstream connection systems of a plurality of distribution systems on the load side of a transformer with one terminal of a secondary winding connected to the ground Circuit A including a means for determining and a circuit B connected between one terminal of the wiring and the ground in an arbitrary system on the downstream side. The circuit B is connected between one terminal of the wiring and the ground. Includes voltage detection determination means, impedance, voltage generation means, and connection switching means. When the voltage detection determination means detects the distribution voltage of the system, the connection switching means selects and connects the impedance between one terminal of the wiring and the ground. to contrast, when not detected connects the voltage generating means connected switching means selects, the circuit a when it detects a current by the circuit a is connected to the impedance or voltage generating means in the circuit B Location and wiring or wiring or equipment lines were installed system and circuit B equipment system discriminating apparatus and outputs a determination result to be identical. 2. The system discriminating apparatus according to claim 1, wherein the determination element that the zero-phase current of the circuit A is due to the impedance or voltage generation means being connected includes the magnitude of the current. The impedance of the previous SL circuit B and a resistor, said circuit determining circuit of A and the phase of the voltage which the voltage or the voltage generating means for voltage detection determining means detects the circuit B is generated on the basis of the detected circuit A current 2. The system discrimination device according to claim 1, wherein a current due to the resistance is detected from the circuit and it is determined that the magnitude of the current due to the resistance is due to the impedance of the circuit B or the voltage generating means being connected. The determination element that the zero-phase current of the circuit A is due to the connection of the impedance or voltage generation means includes the sign of the encoded signal, and the impedance or voltage generation means is encoded and controlled by the encoding control means. The system discriminating apparatus according to claim 1, wherein:

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