KR101021969B1 - System and method for detecting ior - Google Patents

Abstract

PURPOSE: A system and a method for monitoring a short circuit by measuring a resistant short circuit current are provided to periodically store an effective resistant short circuit current and transmit it to a manager terminal, thereby enabling a manager to easily check a short circuit state. CONSTITUTION: If a load device connected to a lower voltage circuit operates, a harmonic wave current generating unit(110) generates the first, third, fifth, seventh, and ninth harmonic wave currents to reduce pressure. A detecting unit(120) detects an output of the harmonic wave currents and provides it to a short circuit current calculating unit. A short circuit current calculating unit(130) calculates an effective resistant short circuit current using an output value of the harmonic wave currents. When the resistant short circuit current value is larger than a preset reference value, a warning unit(140) transmits an SMS which warns a terminal of a manager.

Description

Earth leakage monitoring system by resistive leakage current measurement and the earth leakage monitoring method {SYSTEM AND METHOD FOR DETECTING IOR}

The present invention relates to a ground fault detection system for detecting a resistive leakage current, and more particularly, to accurately detect only a leakage current flowing to the ground, i.e., an effective resistive leakage current (Ior), from the leakage current (Io) flowing on the ground. The present invention relates to a ground fault monitoring system and a ground fault monitoring method using a resistive leakage current measurement that allows an administrator to confirm an accurate ground fault state by causing a leak alarm to be made based on the detection result.

The present invention relates to an earth leakage monitoring system by a resistive leakage current measurement and an earth leakage monitoring method thereof.

It is rare to be aware of the existence of electricity in everyday life, but as it is known, it has been used in various fields as an energy source or information or communication, and has become an integral part of our society.

While the use of such electricity is convenient, it also poses a significant risk of mismanagement and proper use. It is also less likely to cause serious accidents such as electric fire, electric shock or power failure.

In general, when the covering of wires and the insulation of electrical equipment are aged or damaged, the insulator is damaged so that the leakage current flows from the wire path to the ground through the location. If the human body touches the place where the leakage current flows, there is a risk of electric shock.In the place where the excessive leakage current flows, overheating occurs due to the arc, and it is ignited by the flammable material around and causes the leakage material.

Therefore, current leakage current is detected and an alarm is made according to the detection result. The leakage current Io is a leakage current Ior flowing between the ground due to wire degradation and a leakage current Ioc flowing in the capacitance. ) Is included. That is, since the leakage current Ior flowing between the ground and the leakage current Ioc flowing in the capacitance are not provided separately, it is impossible to find a cause causing a short circuit fire.

In recent years, as harmonic devices such as inverter devices are increased, harmonics or harmonic currents are included in leakage current.

On the other hand, the cause of the leakage current or the like is the leakage current (Ior) flowing between the earth due to the wire deterioration, and if only the leakage current (Ior) flowing between the earth due to the wire deterioration can be detected accurately, It will be possible to check and avoid catastrophes such as dial-up materials.

However, in the present case, the alarm is sounded or the circuit is automatically cut off after detecting the leakage current (Io), so the alarm often occurs even in a normal case, and thus the user distrusts it. There is a problem.

Accordingly, the present invention has been made to solve the above problems of the prior art, the present invention is a leakage current flowing to the ground by the wire degradation in the leakage current (Io) flowing on the ground, that is, effective resistive leakage current (Ior) It is an object of the present invention to provide a ground fault monitoring system and a ground fault monitoring method using a resistive leakage current measurement that allows an administrator to check an accurate ground fault state by accurately detecting a bay and allowing a leak alarm to be made based on the detection result.

In addition, the present invention periodically stores the leakage current flowing to the ground due to wire degradation, that is, the effective resistance leakage current (Ior) value, and periodically transmits the effective resistance leakage current (Ior) value to the manager terminal, the effective When the resistance leakage current (Ior) value is higher than the preset reference value, a leakage alarm system and an earth leakage monitoring system using a resistance leakage current measurement that allows the administrator to easily check the leakage state by notifying the administrator terminal of the leakage alarm. The purpose is to provide.

In order to achieve the above object, the earth leakage monitoring system by the resistive leakage current measurement according to the present invention has a basic, third, fifth, seventh, and ninth order when a load device connected to a low voltage circuit is operated. A harmonic current generator for generating harmonic currents to reduce pressure; A detector for detecting an output of the harmonic currents and providing the output to a leakage current (Ior) calculator; A leakage current (Ior) calculation unit for calculating an output value of the harmonic currents and calculating an effective resistive leakage current (Ior) value using the output value; And an alarm unit configured to transmit an SMS for notifying an alarm to a terminal of an administrator when the resistance leakage current (Ior) value calculated by the leakage current calculator is equal to or greater than a preset reference value.

The third and ninth harmonic current output lines are connected to a high-low voltage transformer in a star-delta (Y-Δ) connection, and the fifth and seventh harmonic currents and basic harmonics are output lines. Is connected to the Class B grounding wire.

In this case, the leakage current calculating unit calculates an output value of the fundamental harmonics, the fifth harmonics, and the seventh harmonic currents, and calculates a current ratio of the fifth harmonic to the seventh harmonic using the output value. It is desirable to obtain a coefficient based on the current ratio of the fifth harmonic and the seventh harmonic and the output value of the fundamental harmonics, and multiply the coefficient by the fundamental harmonic current value to calculate the effective resistive leakage current (Ior) value.

The earth leakage monitoring system using the resistance leakage current measurement further includes a central controller configured to process the resistance leakage current (Ior) value calculated by the leakage current calculator to be stored in the storage unit over time.

The earth leakage monitoring system using the resistive leakage current measurement further includes a display unit displaying an effective resistive leakage current (Ior) value and an invalid leakage current (Ioc) value calculated by the leakage current calculator.

On the other hand, the central controller, if the resistive leakage current (Ior) value calculated by the leakage current calculation unit is more than a predetermined reference value to process the buzzer to sound or to process the LED to emit light.

In order to achieve the above object, the earth leakage monitoring method of the earth leakage monitoring system using the resistive leakage current measurement according to the present invention is based on the fact that, when a load device having a harmonic current generating unit connected to a low voltage circuit is operated, (A) depressurizing and generating seventh and ninth harmonic currents; (B) a detection unit detecting the output of the harmonic currents generated by the step (A) and providing the leakage current calculation unit; (C) calculating, by a leakage current calculator, an output value of the harmonic currents, and using the output value, an effective resistive leakage current (Ior) value; And (D) transmitting, by the alarm unit, an SMS for notifying an alarm to the terminal of the administrator when the resistance leakage current (Ior) value calculated in the step (C) is equal to or greater than a preset reference value.

At this time, the step (C), the leakage current calculation step (C1) to obtain the output value of the fundamental harmonics, fifth harmonics, seventh harmonic currents; (C2) obtaining a current ratio between the fifth harmonic and the seventh harmonic by using the output of the fifth harmonic and the seventh harmonic obtained by the leakage current calculating unit (C1); (C3) the leakage current calculating unit obtaining a coefficient based on the current ratio of the fifth harmonic and the seventh harmonic and the output value of the fundamental harmonic; And (C4) calculating the effective resistance leakage current (Ior) value by multiplying the coefficient obtained in the step (C3) by the fundamental harmonic current value.

On the other hand, the central control unit (E) step of processing so that the resistive leakage current (Ior) value calculated by the step (C) is stored in the storage unit for each time; preferably further comprises a.

And (F) processing the central control unit to display the effective resistive leakage current (Ior) value calculated by the step (C) on the display unit.

The control unit may further include a step (G) of causing the buzzer to sound or the LED to emit light when the effective resistive leakage current (Ior) value calculated by the step (C) is greater than or equal to a preset reference value. .

According to the present invention, the present invention accurately detects only the leakage current flowing to the ground, i.e., the effective resistive leakage current (Ior) flowing from the ground, from the leakage current (Io) flowing on the ground, and the leakage alarm is based on the detection result. By doing so, there is an advantage that can check the exact leakage state.

In addition, the present invention periodically stores the leakage current flowing to the ground due to wire degradation, that is, the effective resistance leakage current (Ior) value, and periodically transmits the effective resistance leakage current (Ior) value to the manager terminal, the effective When the resistance leakage current (Ior) value is more than the predetermined reference value, there is an advantage that the administrator can easily check the short-circuit state by notifying the administrator terminal while the leakage alarm.

In addition, the present invention may disappear the basic diagnosis of the insulation measurement (once a year) by megatesupa to diagnose the short-circuit, and always check the progress of the insulation degradation through the year-round monitoring system system to ensure complete disaster prevention And it is installed in a specific place has the advantage that can fundamentally prevent electrical disasters.

1 is a block diagram showing the internal configuration of a ground fault monitoring system using a resistive leakage current measurement according to a preferred embodiment of the present invention.
Figure 2 is a flow chart showing the operation of the earth leakage monitoring system by the resistance leakage current measurement in accordance with a preferred embodiment of the present invention.

An earth leakage monitoring system using the resistive leakage current measurement of the present invention will be described in detail with reference to FIG. 1.

Figure 1 is a block diagram showing the internal configuration of the earth leakage monitoring system by the resistance leakage current measurement in accordance with a preferred embodiment of the present invention.

As shown, the earth leakage monitoring system 100 by the resistance leakage current measurement of the present invention is harmonic current generation unit 110, the detection unit 120, the leakage current (Ior) determination unit 130, the alarm unit 140, The central controller 150, the display unit 160, the buzzer 170, the LED 180, and the storage 190 are included.

When the load device connected to the low voltage circuit is operated, the harmonic current generating unit 110 generates and decompresses the basic, third, fifth, seventh, and ninth harmonic currents.

In this case, the third and ninth harmonic current output line is connected to a high-voltage transformer in a star-delta (Y-Δ) connection, and the fifth and seventh harmonic currents and fundamental harmonics are output. The line is connected to a Class B ground wire.

The detector 120 detects the output of harmonic currents generated by the harmonic current generator 110, and provides the output to the leakage current Ior calculator 130.

The leakage current Ior determiner 130 calculates an output value of the harmonic currents, and then calculates an effective resistance leakage current Ior value and an invalid leakage current Ioc value using the output value.

More specifically, the leakage current (Ior) determiner 130 calculates output values of the fundamental harmonics, the fifth harmonics, and the seventh harmonic currents, and uses the output values to determine the fifth and seventh harmonics. Obtaining a current ratio, obtaining a coefficient based on the current ratio of the fifth harmonic and the seventh harmonic and an output value of the fundamental harmonics, and multiplying the coefficient by the fundamental harmonic current value to calculate an effective resistive leakage current (Ior) value will be.

At this time, the effective leakage current Ioc may be obtained by subtracting the effective resistance leakage current Ior from the leakage current Io flowing through the ground.

The alarm unit 140 transmits an SMS for notifying an alarm to a terminal (not shown) of the manager when the resistance leakage current Ior value calculated by the leakage current calculator 130 is equal to or greater than a preset reference value.

As described above, when a leakage current occurs, a short message is transmitted to the terminal of the administrator, so that the person in charge can go to the place where the leakage occurs and take immediate action, thereby effectively preventing an electric shock accident and a fire caused by the leakage. There is an advantage.

The central controller 150 processes the resistive leakage current Ior value calculated by the leakage current calculator 130 to be stored in the storage unit in time.

In addition, the central controller 150 processes so that the effective resistive leakage current Ior value and the invalid leakage current Ioc value calculated by the leakage current calculator 130 are displayed on the display unit.

Meanwhile, the central controller 150 may transmit the effective resistive leakage current Ior value and the invalid leakage current Ioc calculated by the leakage current calculator 130 in a short message form to the manager terminal in real time.

As described above, the manager has an advantage of easily checking the short-circuit state through the display unit or his terminal.

The central controller 150 processes the buzzer 170 to sound or the LED 180 to emit light when the resistance leakage current Ior value calculated by the leakage current calculator 130 is equal to or greater than a preset reference value.

In addition, the central controller 150 may control the power supply to be cut off so that a short circuit fault does not occur when the resistance leakage current Ior value calculated by the leakage current calculator 130 is equal to or greater than a preset reference value.

The display unit 160 displays the effective resistive leakage current Ior value and the invalid leakage current Ioc value. The display unit 160 generally uses a liquid crystal display (LCD).

The storage unit 190 stores the manager's information (for example, the manager's name, the manager's mobile phone number, etc.), and the resistive leakage current (Ior) value calculated by the leakage current calculator 130 is stored in a table for each time. do. The storage unit 190 may be provided with various storage media, such as an EPROM, a flash memory, or an external memory, depending on the capacity of data to be stored.

Hereinafter, to help the understanding of the description, the operation principle of the ground fault monitoring system by the resistance leakage current measurement will be described in detail with reference to one embodiment.

When the load device connected to the low voltage circuit is operated, the third, fifth, seventh and ninth harmonic currents are generated due to the characteristics of the rectifier circuit and the magnetic material inside the load.

Among the harmonic currents, the third harmonic current and the ninth harmonic current cause the low-voltage transformer connection to make a star-delta (Y- △) connection so that a circulating current flows in the second wound line in the delta-connected transformer. do. As a result, most of the transformer's output terminals do not appear.

On the other hand, the fifth harmonic current and the seventh harmonic current have a form of voltage drop (dropping voltage) on the high voltage side. At this time, the voltage drop on the high voltage side adds another share of demand, and the terminal voltage including harmonics appears on the low voltage side of the transformer.

On the other hand, the low voltage terminal voltage indicating the influence of the high-voltage distribution line includes the fifth harmonic voltage and the seventh harmonic voltage, the ratio of the fifth harmonic voltage and the seventh harmonic voltage is constant. As a result, the component ratios of the fifth harmonic current and the seventh harmonic current flowing through the Class B ground line change according to the comparison of the capacitance [C] and the insulation resistance [R]. In addition, as the length of the converter increases, the inductance increases and the capacitance increases, so the fundamental wave components included in the Class B ground wire increase, so that the ratio of the fifth harmonic current and the seventh harmonic current is different.

Therefore, after measuring the components of the fundamental wave, the fifth harmonic current, and the seventh harmonic current included in the class B grounding line, the current ratios of the fifth harmonic current and the seventh harmonic current are obtained, and the fifth order is obtained. The coefficient for the fundamental wave can be obtained from the current ratio of the harmonic current and the seventh harmonic current and the magnitude of the fundamental wave, and the coefficient can be multiplied by the fundamental wave current to calculate the effective resistive leakage current (Ior) value.

Hereinafter, an operation process of a ground fault monitoring system using a resistive leakage current measurement according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a flowchart illustrating an operation process of the ground fault monitoring system using a resistive leakage current measurement according to a preferred embodiment of the present invention.

First, when the load device in which the harmonic current generator 110 is connected to the low voltage circuit is operated (step S100), the basic, third, fifth, seventh, and ninth harmonic currents are generated and decompressed ( Step S110).

Then, the detection unit 120 detects the output of the harmonic currents generated by the step S100 and provides the leakage current calculation unit 130.

Then, the leakage current calculator 130 obtains the output values of the harmonic currents, and calculates an effective resistive leakage current Ior value using the output values.

More specifically, the leakage current calculator 130 calculates output values of the fundamental harmonics, the fifth harmonics, and the seventh harmonic currents (step S120).

Thereafter, the leakage current calculator 130 obtains a current ratio of the fifth harmonic to the seventh harmonic using the output values of the fifth harmonic and the seventh harmonic obtained in step S120 (step S130).

Then, the leakage current calculator 130 calculates a coefficient based on the current ratio of the fifth harmonic and the seventh harmonic and the output value of the fundamental harmonic (step S140).

 Then, the leakage current calculating unit 130 calculates the effective resistive leakage current Ior value by multiplying the coefficient obtained in the step S140 by the fundamental harmonic current value (step S150).

Thereafter, the alarm unit 140 determines whether the resistance leakage current Ior value calculated by the step S140 is equal to or greater than a preset reference value (step S160).

Thereafter, when the resistive leakage current Ior value calculated by the step S140 is equal to or more than a preset reference value, the alarm unit 140 transmits an SMS notifying an alarm to the terminal of the manager (step S170).

In addition, it is desirable to process the SMS buzzer 170 or the LED 180 to emit light at the same time as sending an SMS informing the administrator of the terminal.

According to the present invention as described above, the present invention has the advantage that the administrator can easily check the leakage by measuring the pure resistance leakage current in the low voltage consumer or low voltage circuit and transmit this information to the manager terminal.

Meanwhile, the central controller 150 processes the resistive leakage current Ior value calculated in step S150 to be stored in the storage unit for each time. The resistance leakage current (Ior) value stored in this way can be provided at the request of an administrator.

In addition, the central controller 150 preferably processes the resistive leakage current Ior value and the invalid leakage current Ioc value calculated by step S150 to be displayed on the display unit 160.

In the above, the present invention has been shown and described with respect to certain preferred embodiments. However, the present invention is not limited only to the above-described embodiment, and those skilled in the art to which the present invention pertains can make various changes without departing from the technical spirit of the present invention. Therefore, the scope of the present invention should not be limited to the specific embodiments, but should be construed as defined by the appended claims.

100: earth leakage monitoring system 110: harmonic current generator
120: detection unit 130: leakage current calculation unit
140: alarm unit 150: central control unit
160: display unit 170: buzzer
180: LED 190: storage unit

Claims (11)

delete A harmonic current generator for generating and decompressing basic, third, fifth, seventh, and ninth harmonic currents when the load device connected to the low voltage circuit is operated;
A detector for detecting an output of the harmonic currents and providing the output to a leakage current (Ior) calculator;
A leakage current (Ior) calculation unit for calculating an output value of the harmonic currents and calculating an effective resistive leakage current (Ior) value using the output value; And
And an alarm unit configured to transmit an SMS to notify an administrator's terminal when a resistance leakage current (Ior) value calculated by the leakage current calculator is equal to or greater than a preset reference value.
The line for outputting the third and ninth harmonic currents is connected to a high-voltage transformer in a star-delta (Y-Δ) connection, and the line for outputting the fifth and seventh harmonic currents and fundamental harmonics is An earth leakage monitoring system based on resistive leakage current measurement, which is connected to a Class B ground wire.
The method of claim 2, wherein the leakage current calculator,
The output values of the fundamental harmonics, the fifth harmonics, and the seventh harmonic currents are calculated, and the current ratios of the fifth and seventh harmonics are calculated using the output values, and the fifth and seventh harmonics are obtained. And a coefficient is calculated based on the current ratio and the output value of the fundamental harmonic, and the effective resistance leakage current (Ior) value is calculated by multiplying the coefficient by the fundamental harmonic current value.
According to claim 3, The earth leakage monitoring system by the resistance leakage current measurement,
And a central controller configured to process the resistive leakage current (Ior) value calculated by the leakage current calculator to be stored in the storage unit over time.
According to claim 4, The earth leakage monitoring system by the resistance leakage current measurement,
And a display unit displaying an effective resistive leakage current (Ior) value calculated by the leakage current calculating unit.
The method of claim 4, wherein the central control unit,
When the resistance leakage current (Ior) value calculated by the leakage current calculation unit is more than a predetermined reference value, the short-circuit monitoring system according to the resistance leakage current measurement, characterized in that the buzzer is sounding or processing so that the LED is emitted.
delete (A) generating and decompressing the basic, third, fifth, seventh, and ninth harmonic currents when the load device connected to the low voltage circuit is operated by the harmonic current generator;
(B) a detection unit detecting the output of the harmonic currents generated by the step (A) and providing the leakage current calculation unit;
(C) calculating, by a leakage current calculator, an output value of the harmonic currents, and using the output value, an effective resistive leakage current (Ior) value;
And (D) transmitting, by the alarm unit, an SMS informing the administrator of an alarm when the resistance leakage current (Ior) value calculated by the step (C) is equal to or greater than a preset reference value.
Step (C) is,
(C1) obtaining a leakage current calculation unit for outputting fundamental harmonics, fifth harmonics, and seventh harmonic currents;
(C2) obtaining a current ratio between the fifth harmonic and the seventh harmonic by using the output of the fifth harmonic and the seventh harmonic obtained by the leakage current calculating unit (C1);
(C3) the leakage current calculating unit obtaining a coefficient based on the current ratio of the fifth harmonic and the seventh harmonic and the output value of the fundamental harmonic; And
And (C4), wherein the leakage current calculating unit multiplies the coefficient obtained in step (C3) by the fundamental harmonic current value to calculate an effective resistive leakage current (Ior) value. How to monitor the system for short circuits.
The method of claim 8,
(E) the central control unit processing such that the resistive leakage current (Ior) value calculated in the step (C) is stored in the storage unit for each time; leakage monitoring by the resistance leakage current measurement further comprises a How to monitor the system for short circuits.
The method of claim 8,
(F) processing the central control unit to display the effective resistive leakage current (Ior) value calculated by the step (C) on the display unit. Earth leakage monitoring method.
The method of claim 8,
(G) the central control unit, if the effective resistive leakage current (Ior) value calculated by the step (C) is more than a predetermined reference value to process a buzzer or LED to emit light; An earth leakage monitoring method of an earth leakage monitoring system by measuring leakage current.

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