KR101108015B1 - Distribution line inspection device - Google Patents

Abstract

The distribution line inspection apparatus is disclosed. The distribution line inspecting apparatus of the present invention supplies a safety voltage of a predetermined level to the distribution line not only at the time of load, but also at the unloaded state in which the supply of commercial AC power to the distribution line is cut off. Clues, short circuits, etc.) can be easily checked without other complicated equipment. The safety voltage has a voltage level such that there is no risk of an electric shock, and thus does not cause an accident during monitoring of the distribution line.

Description

Distribution Line Inspection Device {Distribution Line Maintaining Apparatus}

The present invention relates to a distribution line inspection device for measuring the voltage and current on the distribution line using a safety voltage, and detects a short circuit and disconnection.

Distribution lines for AC power that are exposed to the outside can be leaked, shorted, or shorted due to deterioration or accidents due to environmental influences.

In the conventional power distribution, even if the distribution line is disconnected or a problem occurs in the load, the central control station cannot recognize this in real time. Especially in the 3-wire system, a bypass line is formed even if an overcurrent flows due to a short circuit. Earth Leakage Breaker (ELB) did not work properly and could not prevent electric shock.

SUMMARY OF THE INVENTION An object of the present invention is to provide a distribution line inspection apparatus capable of inspecting a distribution line by measuring voltage and current on a distribution line using a safety voltage, detecting a short circuit and disconnection, and transmitting the result to a manager device.

Another object of the present invention is to provide a distribution line inspection device that eliminates the risk of electric shock due to power distribution line equipment or short-circuit despite the inspection and repair performed at the same time by using a safety voltage in the distribution line inspection.

A distribution line inspection apparatus for achieving the above object includes a main body mounted at an electrical node on a distribution line for distributing a commercial AC power source of a distribution panel to a load side, and a terminating resistor provided in parallel with the load at an end of the distribution line. .

The main body includes a detector including a current sensor and a voltage sensor to measure the voltage and current of the node, a safety voltage supply unit to output a safety voltage to the distribution line, and a controller.

The controller may be configured to control the safety voltage supply unit to output the safety voltage when it is determined that the commercial AC power is not supplied to the distribution line based on the voltage measured by the detection unit. The disconnection and the leakage state of the distribution line are determined based on voltage, current, and leakage current values.

According to an embodiment, the inspecting device may further include a termination relay provided between the distribution line and the termination resistor and separating the termination resistor from the distribution line when the commercial AC power is supplied to the distribution line. .

In addition, the inspection apparatus may operate by receiving its own operating power from a distribution line in front of the breaker or from an internal or external battery.

The distribution line inspection apparatus according to the present invention can not only check the status (voltage, current, disconnection, short circuit, etc.) of the distribution line while the commercial AC power is being supplied to the distribution line, but also supply the commercial AC power to the distribution line. Even in this disconnected 'no load' state, it is possible to simply check the status of the distribution line using the safety voltage and the terminating resistor. Therefore, even if there is not a lot of additional equipment in the existing distribution facilities, it is possible to simply check the status of the distribution line only with the inspection device.

The safety voltage uses a voltage level without the risk of human electric shock, so there is no danger of an accident due to the safety voltage during the inspection.

1 is a view illustrating a distribution line in which a distribution line checking apparatus according to an embodiment of the present invention is installed;
2 is a block diagram of a distribution line inspection apparatus according to an embodiment of the present invention, and
3 is a flowchart provided to explain the operation of the distribution line inspection apparatus of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the drawings.

Referring to Figure 1, the distribution line inspection device of the present invention (hereinafter simply referred to as "checking device") is installed on the distribution line 10 for supplying AC power to the load side connected in parallel with each other, the distribution line 10 It can detect leakage or disconnection of the phase and measure the voltage and current of the installed point (electrical node).

The inspection apparatus includes a main body 110 mounted at one point on the distribution line 10 for measurement, and a termination device 130 installed at the end of the distribution line 10 for measurement of the main body 110. Here, one point on the distribution line 10 where the main body 110 is installed corresponds to an electrical node (hereinafter referred to as 'measurement node 11'). The measuring node 11 is not an electrical node designated to satisfy special conditions, and only an electrical node provided with the main body 110 is sufficient.

However, when the distribution board 51 for supplying AC power to the load (31, 33) installed in a predetermined range region as shown in Figure 1, the main body 110 is mounted near the distribution board 51, the distribution board 51 Is preferably supplied with power for operation. When a short circuit or disconnection occurs in the distribution line 10, the distribution panel 51 or the like cuts off the supply of AC power to the distribution line 10 using the circuit breaker 53. In this case, the measurement node 11 will be limited to the range that can receive power from the distribution panel 51, and the following description will also be described based on such a situation.

2, the main body 110 includes a current sensor 101 and 103, a voltage sensor 105, a detection unit 107, a safety voltage supply unit 109, a display unit 111, an input unit 113, and a communication interface unit. 115 and a controller 117. Although not shown in FIG. 2, the main body 110 naturally includes a DC power supply device (not shown) for receiving AC power from the distribution panel 51 or the distribution line 10 and using it as an internal DC operation power source.

The terminator 130 includes a terminating relay 131 and a terminating resistor 133. The termination relay 131 is open when a commercial AC power supply (for example, 220V AC) is supplied to the distribution line 10, and terminates when the safety voltage to be described below is supplied to the distribution line 10. 133 is connected to the distribution line 10 in parallel with the load (31, 33) to form a closed circuit. The main body 110 allows the terminal resistor 133 to flow a safety voltage on the distribution line 10 connected to the terminal, and then performs voltage / current measurement or disconnection / leakage state detection. Since the termination resistor 133 is electrically connected to the distribution line 10 at all times, the termination relay 131 is not an essential configuration of the present invention.

The detector 107 detects the voltage, current, resistive leakage current Igr, etc. of the measurement node 11 by using the current sensors 101 and 103 or the voltage sensor 105. The current sensors 101 and 103 correspond to a zero current transformer (ZCT) 101 or an alternating current transformer CT (Current Transformer) 103 for sensing a current, and the voltage sensor is a potential current transformer for detecting a voltage. PT: Potential Transformer (105) and the like. The detector 107 provides the measurement result to the controller 117.

The detector 107 may adjust the sensitivity for detecting the magnitude of the current or the voltage by changing the internal reference value, which is a reference for magnitude comparison, under the control of the controller 117.

The safety voltage supply unit 109 supplies test power of a predetermined size through the measurement node 11. The test power source has a voltage enough to check the distribution line 10, but should correspond to a size that does not cause an electric shock. For example, the safety voltage is about 30 V or less, but an AC of less than 50 V or a DC contact voltage of less than 120 V is preferable.

The display unit 111 displays various information provided by the control unit 117 so that the user can visually or audiologically recognize the display unit 111 and displays a display device such as an LED or an LCD or a buzzer or a speaker. Or the like.

The input unit 113 receives various setting values required for the operation of the inspection apparatus from the user and provides them to the controller 117. The input unit 113 may be applied to a keyboard, a touch pad, and various other known input devices. The user may view various information displayed on the display unit 111 and other user interfaces, and input various setting values necessary for the operation of the inspection apparatus through the input unit 113.

The communication interface 115 is connected to a manager device (not shown) by a wired or wireless interface, transmits various data provided by the controller 117 to the manager device, and receives data transmitted by the manager device from the controller 117. As a device provided to a mobile phone, it is preferable to use a wireless communication or a power line communication (PLC) method in consideration of portability. In the case of power line communication, the communication interface 115 is connected to the distribution line 10, in particular the front end of the breaker 53 of the distribution panel 51. Here, the manager device includes not only a control server but also a manager portable terminal such as a personal digital assistant (PDA), a mobile phone, and the like.

The controller 117 controls the overall operation of the inspection apparatus of the present invention. In particular, the controller 117 controls the overall configuration to perform voltage / current measurement or leakage / disconnection detection at the measurement node 11 on the distribution line 10.

Hereinafter, with reference to FIG. 3, the operation of the inspection apparatus 200 will be described based on the operation of the control unit 117.

<Determination of AC Power Supply: Steps S301 to S307>

The voltage / current measurement and the detection of a short circuit / disconnection by the control unit 117 include a “load state” in which power is supplied from the distribution panel 51 to the loads 31 and 33, and the load 31 from the distribution panel 51. 33) is divided into 'no-load' state where power is not supplied.

The controller 117 determines that the voltage is in the no-load state if the voltage is within the commercial AC voltage range based on the voltage of the measurement node 11 extracted by the voltage sensor 105, and the no-load state if the voltage is not detected. If it is determined that the oil load, the control unit 117 detects the voltage / current measurement and the leakage / disconnection of the distribution line 10 based on the AC power supplied from the distribution panel 51 (S301, S303).

In the case of no load state, the controller 117 controls the safety voltage supply unit 109 to output the safety voltage to the distribution line 10, and controls the sensitivity of the detection unit 107 to be within the safety voltage range. . As the safety voltage is supplied to the distribution line 10, the termination relay 131 terminates by connecting the termination resistor 133 to the distribution line 10 (S305 and S307).

<Voltage check: step S309>

The voltage check is performed by the detector 107 measuring the voltage of the measurement node 11 using the potential current transformer 105 and providing the voltage to the controller 117. Since the commercial AC power is supplied from the distribution panel 51 in the oil load state, the detection unit 107 detects the voltage of the measurement node 11 with a sensitivity for measuring the commercial AC voltage range. In the unloaded state, since the supply of the commercial AC power supply to the distribution panel 51 is cut off and the safety voltage is supplied, the detector 107 detects the voltage of the measurement node 11 with a sensitivity for measuring the safety voltage range.

<Current check: S311 step>

The current check is performed by the detection unit 107 measuring the current of the distribution line 10 using the AC current transformer 103 and providing it to the control unit 117. Since the commercial AC power is supplied from the distribution panel 51 in the oil load state, the detector 107 detects the current of the distribution line 10 with a sensitivity for measuring the commercial AC current range.

In the unloaded state, the supply of commercial AC power to the distribution panel 51 is cut off, the safety voltage is supplied to the distribution line 10, and the termination relay 131 connects the termination resistor 133 to the distribution line 10. A closed path is formed in place of the loads 31 and 33. Accordingly, the detector 107 measures the current flowing through the distribution line 10 terminated by the termination resistor 133 with the sensitivity of measuring the test current range.

The detection of voltage and current in the unloaded state does not need to proceed separately in steps S309 and S311.

<Disconnect Detection: Step S313>

Disconnection detection corresponds to detecting an equivalent resistance of the distribution line 10 as viewed from the load side or the termination resistor side, and a value far exceeding the resistance range by the loads 31 and 33 or the termination resistor 133 (for example, infinity). When it comes out to determine that the distribution line 10 is disconnected.

To this end, the detection unit 107 is based on the voltage value measured using the potential current transformer 105 and the current value measured using the AC current transformer 103, in a state where a commercial AC voltage or a safety voltage is confirmed. If it is confirmed that no current flows, it is determined as disconnection. Similarly, the sensitivity of the detector 107 in the unloaded state and the unloaded state is controlled differently by the controller 117.

<Leakage Detection: Step S315>

The earth leakage monitoring is performed by measuring a resistance leakage current value generated in the power distribution line 10 when it is not in a disconnected state. To this end, the detection unit 107 provides a resistance leakage current (Igr) value on the power distribution line 10 measured by the image current transformer 101 to the control unit 117, and measures it using the AC current transformer 103. One current value is provided to the control unit 117 for disconnection monitoring. If the resistance leakage current Igr is greater than or equal to a predetermined value, the controller 117 determines a short circuit, but distinguishes it from the disconnection state by using a current value through which current flows in the distribution line 10.

Similarly, the sensitivity of the detector 107 in the unloaded state and the unloaded state is controlled differently. In addition, in the unloaded state, the termination resistor 133 terminates the distribution line 10 in place of the loads 31 and 33 to form a closed passage.

Preferably, the detector 107 detects a time point at which the voltage of the measurement node 11 is zero voltage (0 V) and measures the output value of the image current transformer 101 at the zero voltage time point. Measure it.

The leakage current Ig is represented by the vector sum of the resistive leakage current Igr, the capacitive leakage current Igc, and the inductive leakage current Igl. The element that causes fire or electric shock by electric leakage is resistive leakage current (Igr). Therefore, a situation where a safety problem actually arises and an administrator needs repair is when a resistive leakage current (Igr) is detected. Inductive leakage current (Igl) is so weak that it is negligible.

In order to measure the resistive leakage current (Igr) value not including the capacitive leakage current (Igc), the detection unit 107 has an instantaneous value of the AC voltage or the safety voltage provided to the loads (31, 33). Measure the leakage current value at the point of 0 V as the resistance leakage current value. This is because the current measured at the instantaneous value of the voltage applied to the load includes only the resistive current from which the capacitive current is removed.

As described above, the controller 117 performs the voltage / current measurement and the leakage / disconnection monitoring together with the detector 107 when the controller 117 determines that there is no load or is determined as no load in step S307. However, such measurement or monitoring is not carried out individually but in combination, so that not only voltage / current measurement but also short-circuit / disconnection monitoring are performed with one voltage and current measurement. For example, the measurement of the current value at the time of the unloading or the measurement of the current value after supplying the safety voltage (S311) itself corresponds to the disconnection monitoring (S313).

In addition, monitoring of the inspection device 200 at no load not only eliminates the cause of human accident by using a safety voltage without the risk of human electric shock, but also can easily check the status of the distribution line without other equipment. .

The control unit 117 notifies the manager device of the measurement or monitoring results of steps S309 to S315 through the communication interface unit 115, enabling the administrator to monitor and at the same time enabling immediate response.

<Other embodiments>

The inspection apparatus according to another embodiment may include an internal or external battery, and may not necessarily receive power from the distribution panel 51. Therefore, the measurement node 11 of such a check device is not limited to the distribution board 51 near, such as between the load 1 31 and the load 2 33.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the invention as defined by the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.

Claims (3)

A main body mounted at an electrical node on a distribution line that distributes the commercial AC power of the distribution panel to the load side;
A terminating resistor provided in parallel with the load at an end of the distribution line; And
A termination relay provided between the distribution line and the termination resistor and separating the termination resistor from the distribution line when the commercial AC power is supplied to the distribution line,
The main body,
A detector including a current sensor and a voltage sensor to measure voltage and current of the node;
A safety voltage supply unit configured to output a safety voltage to the distribution line; And
On the basis of the voltage measured by the detector, when it is determined that the commercial AC power is not supplied to the distribution line, the controller controls the safety voltage supply unit to output the safety voltage, and then the voltage and current measured by the detector. And a control unit for determining disconnection and short-circuit state of the distribution line with a leakage current value.
delete The method of claim 1,
And when the breaker in the distribution panel is operated to reach the unloaded state, the self-operating power is supplied from a distribution line in front of the circuit breaker or supplied from an internal or external battery.

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