KR100906966B1 - When intercept electric leakage, device and power distributor having earth leakage current analysis function - Google Patents

Abstract

A device and a distribution board are provided to get at the root of an accident by operating an earth leakage circuit breaker and making an output level of photo-coupler dropped. A zero-phase current transformer(12) detects a leakage current in a power line(10), and an earth leakage breaker(11) is operated by a detection value of the zero-phase current transformer. A voltage unit senses a voltage from the power line and generates a synchronizing signal and a control power. A resistor leakage current output unit(30) calculates resistor leakage current from a mixed leakage current. An earth leakage breaker signal generator(40) sense the suspension of the power line and outputs an interception of power supply signal.

Description

When Intercept Electric Leakage, Device and Power Distributor Having Earth Leakage Current Analysis Function}

The present invention relates to a device and a distribution board having a leakage current analysis function in the case of a ground fault interruption. In particular, the resistive component, the capacitive component, and the composite component of the leakage current can be classified and detected, and the ground fault interrupter is combined with the ground fault breaker. The present invention relates to a device and a distribution panel capable of identifying the cause of an electric leakage interruption by detecting and storing leakage current values and displaying them into resistive, capacitive and synthetic components.

As is well known, an image current transformer (ZCT: Zero Current Transformer) is used to detect a leakage current (Ig) in a cable line that supplies power to a load, such as a distribution panel or a distribution panel in the related art. Ig) is a composite leakage current Ig, which is a value composed of the vector sum of the resistive leakage current Igr and the capacitive leakage current Igc as shown in FIG.

Here, the resistive leakage current (Igr) is a leakage current (Igr) flowing from the cable line to the ground due to deterioration of ground insulation resistance of the cable line or deterioration of earth insulation resistance of an electric device connected to the cable line. If it is large, an electric fire is caused, and if a human body is connected to an electric wire or an electric device of which earth insulation resistance is deteriorated, a human accident may occur due to an electric shock that electricity flows to the earth through the human body.

On the other hand, the capacitive leakage current (Igc) is a leakage current (Igc) due to the capacitance that is always present between electric wires and electric devices and the ground, and is a leakage current (Igc) irrelevant to an electric shock or an electric fire. The leakage current Igc increases as the length of the wire increases, the moisture increases, and the number of electric devices including harmonics increases and the inter-ground capacitance increases.

Therefore, the earth leakage breaker operated by the detection value of the image current transformer which detects such a composite leakage current (Ig) is to prevent electric shock or electric fire by increasing the resistive leakage current (Igr) due to the ground fault or deterioration of earth insulation resistance. Not only does it work, but it is also caused by a large number of harmonic-containing electrical devices tied to long wires or by transient increases in capacitive leakage current (Igc) in wet weather.

If the earth leakage breaker is operated in this way, it is necessary to establish the countermeasure and establish countermeasures.However, in the case of rain, the earth leakage breaker may occur temporarily. It is difficult to identify the cause of the ground fault interruption because the value and the component are unknown and there is a problem in that accurate and effective measures cannot be made.

An object of the present invention is to always be installed on the load side, such as distribution panel of the electrical circuit to which the leakage occurs frequently to detect and display the composite leakage current and the resistive leakage current and capacitive leakage current at the same time, The present invention provides an apparatus and a distribution panel that can accurately determine the cause of an electric leakage accident by storing, calculating, and displaying a leakage current component and its value at the instant of the occurrence.

In order to achieve the above object, the present invention is a device installed in a power line connected to an earth leakage breaker and an image current transformer, and has a function of measuring and analyzing leakage current during an earth leakage interruption. A resistive leakage current calculating unit connected to the voltage generating unit for generating power, the image current transformer and the output of the voltage unit and calculating a resistive leakage current from the leakage current detected from the image current transformer according to the synchronization signal of the voltage unit; After that, it is connected to the power line in the load direction and monitors the power line disconnection and outputs a disconnection signal, and receives the output of the image current transformer, the resistive leakage current calculating unit, and the earth leakage blocking signal generating unit as inputs. Microcomputer that stores, calculates and displays leakage current for each component according to the output of the generator It is composed of a processor unit.

In addition, the present invention configures a leakage current analyzer having a function of analyzing the leakage current in the case of the earth leakage breaker as a module and connects to the power line and the image current transformer inside the case, so that the distribution panel that can analyze the leakage current in the earth leakage breaker to provide.

In this way, the present invention can simultaneously measure and display the composite leakage current, the resistive leakage current, and the capacitive leakage current to determine whether the leakage current is caused by deterioration of the earth insulation resistance, the ground-to-ground capacitance or the harmonic generator of the cable. It is possible to check whether it is caused by an increase, and in particular, whether the earth leakage breaker is caused by a ground fault, whether it is caused by an increase in the earth-to-ground capacitance due to moisture or moisture due to rain, or increasing the use of an inverter or a UPS. It is possible to check whether it is caused by harmonics, and thus it is possible to obtain a useful effect to identify the exact cause of an accident.

In addition, the present invention is installed in the outdoors, such as a street lamp line and the length of the wire line is installed in the line of the earth leakage circuit frequently occurs due to the earth capacitance capacity of the cable to monitor the state of the wire line when the cause of failure when the circuit breaker It is particularly useful for identification.

Referring to the present invention in more detail with reference to the accompanying drawings as follows.

The overall configuration of the apparatus and the distribution panel having the leakage current analysis function at the time of the electrical leakage interruption according to the present invention is illustrated in FIG.

As can be seen from the above, the present invention is an image current transformer 12 (ZCT: Zero Current Transformer) for detecting a leakage current in the power line 10, and an earth leakage breaker operated by the detection value of the image current transformer 12 (11) is provided and connected to the voltage unit 20 for detecting a voltage from the above-described power line 10 to generate a synchronization signal and a control power supply, and the output of the image current transformer 12 and the voltage unit 20 described above. The resistive leakage current calculating unit 30 calculates a resistive leakage current from the synthesized leakage current detected from the image current transformer 12 according to the synchronization signal of the voltage unit 20, and the above-described earth leakage breaker 11 in the load direction. An earth leakage interrupting signal generator 40 connected to the power line 10 to monitor the power failure of the power line 10 and outputting a disconnection signal, the image current transformer 12, the resistive leakage current calculating unit 30, and a ground fault The earth leakage blocking signal generator 4 receives the output of the blocking signal generator 40 as an input. The microprocessor unit 50 may store and display the composite leakage current and the resistive leakage current at the time of the earth leakage interruption according to the output of 0).

For example, the components of the above-described voltage unit 20 detect the voltage supplied by being connected to the power line 10 of the primary side (power side) of the ground fault circuit breaker 11, The transformer 21 converts and rectifies and outputs a synchronous signal through the transformer 21 and the rectifier 22, and the rectifier 23 can be used as a control power source for the resistive leakage current calculating unit 30 and the microprocessor unit 50. Can be supplied with constant voltage.

In addition, the above-described resistive leakage current calculator 30 corrects and inputs a phase difference between the synthesized leakage current detected from the image current transformer 12 and the voltage through the phase corrector 31, and receives an AC voltage from the voltage unit 20. An accumulator 32 for receiving a synchronous signal according to a phase change of and calculating a resistive leakage current by performing half-wave integration for each half period of the voltage according to the synchronous signal. 32) converts the resistive leakage current output from the 32 into A / D or D / A according to the characteristics of the microprocessor unit 50, and constitutes a D / A converter 33 for outputting the input to the microprocessor unit 50. It is possible.

The reason why the resistive leakage current component may be calculated by the accumulator 32 in the resistive leakage current calculating unit 30 is that the synthesized leakage current detected from the image current transformer 12 is equal to the resistive leakage current as shown in FIG. 1. It is composed of vector sum of capacitive leakage current, resistive leakage current is in phase with voltage, and capacitive leakage current is 90 degrees ahead of voltage so that only resistive leakage current component can be calculated by phase difference from voltage in composite leakage current. Will be.

In more detail, since the voltage v is a sine wave, it can be expressed as Equation 1.

<식1>

<Equation 1>

이며, f는 전압주파수이고, t는 시간이다.Where V is the effective value of voltage (v),

F is the voltage frequency and t is the time.

Therefore, since the synthesized leakage current ig flowing through the power line 10 is also a sine wave, it may be represented by Equation 2 in the same manner as in Equation 1.

<식2>

<Equation 2>

는 전압(v)과 합성 누설전류(ig)와의 위상각이다.Likewise, where Ig is the effective value of the composite leakage current (ig),

Is the phase angle between the voltage v and the synthesized leakage current ig.

구간에서 적분(P)하면 식3과 같다.This composite leakage current ig is obtained when the polarity of the voltage v is positive, that is,

Integrating (P) in the interval is shown in Equation 3.

<식3>

<Equation 3>

However, as shown in FIG. 1, since the resistive leakage current Igr is the same as Equation 4, when Equation 4 is substituted into Equation 3, it can be expressed as Equation 5.

<식4>

<Equation 4>

<식5>

(Eq. 5)

구간에서 적분값(P)에 비례한다.That is, the resistive leakage current Igr

Proportional to the integral value P in the interval.

구간에서 적분(Q)하면 식6과 같다.In addition, the above-described synthesized leakage current (ig) is obtained when the voltage (v) polarity is negative, that is,

Integrating (Q) in the interval is shown in Eq.

<식6>

<Equation 6>

Even in this case, since the resistive leakage current Igr is the same as that of Equation 4, the equation 4 can be expressed as Equation 7 by substituting Equation 6.

<식7>

<Eq. 7>

구간에서 적분값(Q)의 절대값에 비례 한다.That is, the resistive leakage current Igr

It is proportional to the absolute value of the integral value (Q) in the interval.

)를 곱하면 저항성 누설전류(Igr)를 구할 수 있는 것이다.Therefore, the integrated leakage current (ig) is integrated every half cycle according to the synchronization signal of the voltage (v).

Multiply by) to obtain the resistive leakage current (Igr).

In addition, the ground fault interrupting signal generator 40 is connected to the power line 10 in the load direction of the ground fault breaker 11 to detect a ground fault when the ground fault breaks (disruption). When the output of the photocoupler 43 is maintained at a high level while the power is disconnected using the 43, the output circuit of the photocoupler 43 drops when the power leakage circuit breaker 11 operates and the power in the load direction is cut off. If the microprocessor unit 50 monitors this, it will be possible to detect a ground fault interruption.

The microprocessor unit 50 includes a microprocessor 51 that receives and processes the outputs of the image current transformer 12, the resistive leakage current calculator 30, and the ground fault interruption signal generator 40, and the microprocessor A memory 52 for storing a set value or an input leakage current value in the input / output of the processor 51, a display unit 53 for displaying the leakage current value, and a stored value stored in the leakage current value display command or the memory 52 In order to input a command such as a value delete command or the like, the switching unit 54 may be configured by connecting a switch or an input device such as a touch input, where the display unit 53 is a FND indicating a leakage current value and a leakage shown. In addition to LEDs that indicate whether the current value is a composite leakage current or a resistive leakage current, the LCD can be used to distinguish between the composite leakage current and the resistive leakage current. have.

)에 의해 산출하여 FND 표시 또는 용량성 누설전류(Igc)가 기준값 이상 일 때 LED로 알림표시를 할 수 있음은 물론이다.In addition, since the microprocessor unit 50 receives the composite leakage current Ig and the resistive leakage current Igr, as shown in FIG.

Of course, when the FND display or the capacitive leakage current (Igc) is greater than the reference value, it can be displayed by LED.

The present invention having such leakage current detection, storage and display functions is characterized by the constant current leakage current (Ig) value, the resistance leakage current (Igr) value and the capacitive capacity by the image current transformer 12 and the resistive leakage current calculation unit 30. The leakage current (Igc) value can be detected and calculated, and, of course, when the ground fault interrupter 11 is operated to cause a ground fault, the ground fault breaker 11 detects whether the ground fault breaker is detected by the ground fault interrupter signal generator 40. The leakage current value at the moment of interruption (disruption) can be stored and displayed to determine whether the cause of the electric leakage interruption is due to an increase in the resistive leakage current (Igr) due to a short circuit or simply by a capacitive leakage current (Igc). It becomes possible.

For example, if the leakage current (Ig) value at the moment of the earth leakage breaker is smaller than the rated non-operating current of the earth leakage breaker 11 as the cause of the earth leakage breaker 11 breaking, the earth leakage breaker 11 itself may be abnormal or malfunction. When the combined leakage current (Ig) at the moment of the earth leakage breaker is larger than the rated non-operating current of the earth leakage breaker 11,

If the resistance leakage current (Igr) value is greater than the rated non-operation current of the earth leakage breaker 11 and the capacitive leakage current (Igc) value is less than the rated non-operation current of the earth leakage breaker 11, the power line is an electric fire or electric shock. The ground fault circuit breaker 11 has been operated due to the ground fault accident

Resistive leakage current (Igr) value is less than the rated breakdown current of the earth leakage breaker 11, and capacitive leakage current (Igc) value is larger than the rated breakdown current of the earth leakage breaker 11, which contains changes in weather and environment or harmonics. It can be determined that the circuit breaker 11 is operated because the capacitance of the power line is increased due to the increase of the device and the capacitive leakage current Igc is increased.

Therefore, the resistive leakage current (Igr) value is significantly smaller than the composite leakage current (Ig) value that caused the circuit breaker 11 to shut off, and the capacitive leakage current (Igc) value is close to the composite leakage current (Ig). If the leakage current breaker 11 is equal to or higher than the rated sensitivity current, the current leakage is interrupted due to the increase in the capacitive leakage current (Igc) due to the increase in the capacitance of the power line 10. In case of the former case, take measures against moisture and moisture. In the latter case, shorten the line section or adjust UPS, inverter, etc. This can be solved.

On the contrary, the capacitive leakage current (Igc) value is significantly smaller than the composite leakage current (Ig) value that caused the breaker operation of the ground fault circuit breaker 11, and the resistive leakage current (Igr) value is the combined leakage current (Ig) value. If it is close to or more than the rated sensitivity current of the earth leakage breaker (11) is a ground fault has occurred in the power line can be solved by finding and recovering the ground point.

In addition, the microprocessor unit 50 stores the rated non-operation current value of the earth leakage breaker 11 as a reference value so that the detected leakage current at the time of the earth leakage breaker is a synthesized leakage current (Ig), a resistive leakage current (Igr), or a capacitive leakage. When the value of each current (Igc) is higher than the reference value, the LED assigned to the leakage current of each component lights up to make it easy to determine whether the ground fault interruption is caused by a ground fault or an increase in capacitance. .

In addition, the present invention modularizes a device capable of analyzing and displaying the leakage current at the time of the earth leakage interruption according to the components by the leakage current analyzer 15 to modularize the power line 10 and the image current transformer inside the case 14 of the distribution panel. In connection with (12), a distribution panel is provided to identify the cause of the short circuit interruption.

As shown in FIG. 3, the present invention includes an earth leakage circuit breaker 11 connected to the power line 10 to detect a leakage current, and operated by a detection value of the image current transformer 12. The branch circuit 13 for branching the above-described power line 10 to supply power to each load, and the above-mentioned circuit breaker 11, the image current transformer 12, and the branch circuit 13 are fixed to an inner plate and casing. In a known distribution panel composed of a case 14, a voltage unit 20 for detecting a voltage from the above-described power line 10 to generate a synchronization signal and a control power supply, and the image current transformer 12 and the voltage unit ( A resistive leakage current calculating unit 30 connected to an output of the circuit 20 and calculating a resistive leakage current from the synthesized leakage current detected from the image current transformer 12 according to the synchronization signal of the voltage unit 20, and the above-described leakage circuit breaker ( 11) is then connected to the power line 10 in the load direction to reduce the power disconnection of the power line 10 The ground fault interruption signal generator 40 for outputting a short circuit signal, and the outputs of the image current transformer 12, the resistive leakage current calculator 30, and the ground fault interruption signal generator 40. The leakage current analyzer 15 including the microprocessor unit 50 that stores, calculates, and displays the leakage current for each component according to the output of the generator 40 may include the power line 10 and the image current transformer in the case 14 described above. It is connected to (12) and it is a distribution panel that can detect, analyze and confirm the leakage current in the case of earth leakage.

In addition, according to the present invention, a method of controlling a device having a leakage current analysis function when a ground fault is interrupted may enable the microprocessor 51 and the memory 52 of the microprocessor unit 50 to operate normally as shown in FIG. 4. Initialization step (S10) for initializing, input storage step (S20) for receiving and storing the composite leakage current detected by the image current transformer 12 and the resistive leakage current calculated by the resistive leakage current calculation unit 30, and earth leakage cutoff The disconnection is judged by the disconnection signal of the signal generator 40, and when disconnection, the last synthesized leakage current value and the resistive leakage current value immediately before the disconnection are stored in the memory 52. Receives a current check command to be displayed on the display unit 53, and returns to the input storage step (S20) again to continue to detect and calculate the composite leakage current and the resistive leakage current (S30) It consists of.

Here, in the above-described input storage step (S20), the microprocessor unit 50 receives the synthesized leakage current detected by the image current transformer 12 and the resistive leakage current calculated by the resistive leakage current calculator 30, and then the synthesized leakage current. And the capacitive leakage current in the vector sum relationship with the resistive leakage current, and display the composite leakage current, the resistive leakage current, and the capacitive leakage current on the display unit 53, respectively.

According to the control method of the device having the leakage current analysis function at the time of earth leakage, the leakage current value that caused the interruption operation (disruption) of the earth leakage breaker 11 can be stored and confirmed later. This will be possible.

1 is a schematic diagram of leakage current component

Fig. 2 is a block diagram illustrating the overall configuration of a device having a leakage current analysis function at the time of an electrical leak interruption according to the present invention.

Fig. 3 is a circuit diagram showing a concrete embodiment of a distribution board which constitutes a leakage current analyzer having a leakage current analysis function at the time of leakage current leakage according to the present invention.

4 is a flowchart illustrating a method of controlling a device having a leakage current analysis function at the time of a ground fault interruption according to the present invention;

* Explanation of symbols for the main parts of the drawings

10: power line 11: earth leakage breaker 12: video current transformer

13: Branch circuit 14: Case 15: Leakage current analyzer

20: voltage section 21: transformer 22: rectifier

23: constant voltage device 30: resistive leakage current calculation unit

31: phase corrector 32: totalizer 33: D / A converter

40: earth leakage breaking signal generator 41: resistor 42: rectifier

43: photo coupler 50: microprocessor section 51: microprocessor

52: memory 53: display unit 54: switching unit

Claims (8)

delete A video current transformer for detecting a leakage current is connected to the power line, an earth leakage circuit breaker operated by the detected value of the video current transformer, a branch circuit for branching the above-described power line to supply power to each load, and the video current transformer and the earth leakage circuit breaker described above. And a known distribution panel composed of a case for fixing a branch circuit to an inner plate and casing, A voltage unit for detecting a voltage from the above-described power line and generating a synchronization signal and a control power source; A resistive leakage current calculating unit connected to the output of the image transformer and the voltage unit as described above and calculating a resistive leakage current by half-integrating a composite leakage current detected from the image current transformer according to a synchronization signal of the voltage unit; After the above-mentioned circuit breaker circuit breaker is connected to the power line in the load direction, the circuit breaker signal generation unit for monitoring the power line disconnection and output the disconnection signal, It consists of a microprocessor unit that receives the outputs of the above-mentioned video current transformer, resistive leakage current calculating unit and the earth leakage blocking signal generator as inputs, and stores, calculates and displays the leakage current for each component according to the output of the earth leakage blocking signal generator. A distribution panel having a leakage current analysis function at the time of a ground fault interruption, characterized by displaying leakage current for each component of the circuit breaker. The method according to claim 2, The above-described voltage unit detects a voltage supplied by being connected to the power line of the primary circuit (power supply side) of the ground fault circuit breaker, converts the detected voltage after rectifying and outputs a synchronous signal, and converts the rectified power into a resistive leakage current calculating unit and a microprocessor. Distribution panel with leakage current analysis function in case of leakage interrupting, characterized by supplying with constant voltage through constant voltage so that it can be used as negative control power. The method according to claim 2, The resistive leakage current calculating unit includes a phase corrector for correcting and outputting a phase of the synthesized leakage current by receiving the synthesized leakage current detected from the image current transformer; Leakage current analysis function at the time of earth leakage interrupting characterized in that it comprises an integrator for calculating the resistive leakage current by integrating the phase-corrected output of the phase compensator and the synchronous signal of the voltage unit according to the synchronous signal. Distribution board. The method according to claim 2, The microprocessor unit includes a memory for storing the leakage current value input to the input / output of the microprocessor which receives and processes the output of the image current transformer, the resistive leakage current calculation unit, and the ground fault interruption signal generator, and a display for displaying the leakage current value. A distribution panel having a leakage current analysis function at the time of the earth leakage cut-off, characterized in that by connecting the unit and the switching unit for inputting the command. The method according to claim 5, And a display panel comprising a FND indicating a leakage current value and an LED indicating whether the displayed leakage current value is a synthetic leakage current or a resistive leakage current. An initialization step of initializing the microprocessor unit by using a device having a leakage current analysis function in case of leakage An input storage step of receiving and storing the resistive leakage current calculated by the resistive leakage current calculating unit which calculates the resistive leakage current by integrating the synthetic leakage current detected by the image current transformer by half wave; Judging the power failure by the power failure signal of the earth leakage blocking signal generator, and storing the composite leakage current and the resistance leakage current that caused the power failure in the memory in the power failure and displaying it on the display when receiving a confirmation command from the input part for the post-check. A control method of a distribution panel having a leakage current analysis function at the time of a ground fault interruption, comprising: a confirmation step of returning to the input storage step again to detect and calculate a composite leakage current and a resistive leakage current. The method according to claim 7, In the above-described input storage step, the microprocessor unit receives the resistive leakage current detected by the image current transformer and the resistive leakage current calculation unit, and calculates the capacitive leakage current having a vector sum relationship between the synthesized leakage current and the resistive leakage current. And displaying the synthesized leakage current, the resistive leakage current, and the capacitive leakage current on the display unit, respectively.

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