KR102011740B1 - Cut-off apparatus for poor insulation - Google Patents

Abstract

The present invention relates to an apparatus for blocking an insulation failure, which is capable of promoting the convenience of management. The apparatus comprises: a radio rectification unit; an alarm unit connected in parallel with an output terminal of the radio rectification unit; a voltage multiplying unit connected in parallel with an input terminal; a reference voltage generating unit including first and second resistors; a comparison voltage generating unit including a third resistor; an operating voltage providing unit including a sixth capacitor and a second Zener diode; a relay switching control unit outputting a relay switching control signal; and a relay switching unit including a relay coil.

Description

Bad insulation breaker {CUT-OFF APPARATUS FOR POOR INSULATION}

The present invention relates to a device for detecting, alarming, and interrupting insulation failure, and more particularly, an insulation failure that allows a good insulation line to be supplied with power normally, and a poor insulation insulation circuit that can cut off the power supply. It relates to a blocking device.

When multiple load circuits are connected to one breaker, the fault point should be detected and repaired with the short circuit interrupted or with all the load circuits switched off in the event of an alarm.

However, the ground fault detection device or the ground fault detection method is various, but it is often difficult to apply such a ground fault detection device or a ground fault detection method depending on the site conditions.

As a method of detecting an electric leak point, it is common to cut a plurality of sections and judge it as an insulation resistance value. In addition, there is a method of detecting the leakage point depending on the experience, but in this case, the detection time can be shortened, but the detection completion time cannot be predicted. In particular, if the load is a lighting device, it is also a problem that the insulation failure detection should be performed in the unlit state, but there are many cases where the supply power cannot be cut off for a long time according to the site conditions.

Since the ground fault detection according to the related art detects an image current of 60 Hz in a live state, when the active line is shorted, detection is well performed due to a potential difference between the active line and the ground. If the neutral wire is shorted, there is no potential difference and it cannot be detected.

In addition, it can only be disconnected if the ground resistance is less than a few kiloohms and the insulation is poor. It is impossible to detect insulation failure sensitively because the capacitive leakage current caused by the capacitor used in the LC filter or the distribution capacitance existing between the line and the ground cannot be ignored due to the current characteristics of the AC state.

For example, conventional miniature earth leakage breakers operate differently by sensitivity, but are more sensitive to harmonic noise currents in the frequency range of 0.1 to 1 kHz, which is generally higher than 60 Hz. However, high frequency noise current is generated when digital power control is performed. In this digital power control, an LC filter is essentially used, and thus a capacitive leakage current is inevitably generated.

Patent No. 10-1813355 Insulation Detector and Electrical Equipment Japanese Patent Publication No. 5818820 Insulation Resistance Detection Circuit JP 2014-153090 Insulation state detection device

The present invention provides an insulation failure blocking device that can detect an active line or a neutral line without distinguishing the insulation resistance between the line and the ground by a DC voltage.

In addition, the present invention provides a poor insulation circuit breaker that allows a good insulation line to be supplied power normally, and a poor insulation line can cut off the power supply with an alarm.

The insulation failure blocking device according to the present invention comprises an input terminal connected to a power supply side, an output terminal connected to a load side, and a relay contact disposed between the input terminal and the output terminal. A full wave rectifier connected in parallel to an input terminal and full-wave rectifying an AC voltage applied through the input terminal; An alarm unit connected in parallel to an output terminal of the full wave rectifying unit and configured to visually or audibly alert the relay contact during opening; A double voltage unit connected in parallel to the input terminal and outputting a double voltage of the input voltage during a positive half cycle of the AC voltage using a plurality of capacitors and a half wave rectifier circuit; A reference voltage generator including first and second resistors connected in parallel with an output terminal of the double voltage unit and generating a reference voltage applied to the second resistor; A comparison voltage generator including a third resistor having one end connected to an output terminal of the double voltage unit and generating a comparison voltage applied to the other end of the third resistor; An operating voltage provider connected in series with the reference voltage generator and including a sixth capacitor and a second zener diode; The operation voltage is supplied from the operation voltage providing unit, and is connected to the reference voltage generation unit and the comparison voltage generation unit, and configured to output a relay switching control signal when the comparison voltage VRG is higher than the reference voltage VR2. A relay switching control unit; And a relay switching unit connected in parallel with the alarm unit and including a relay coil controlled to the relay switching control signal to open and close the relay contact point.

The relay switching controller may include a single junction transistor and a photodiode connected in series connected in parallel to the operation voltage providing unit; A FET connected in parallel between the gate of the single junction transistor and the other end of the photodiode; An eighth capacitor and a third zener diode of a parallel connection coupled between the gate and the drain of the FET; And a seventh diode disposed between the gate and the source of the FET.

The alarm unit may include a series connected LED and a first zener diode connected in parallel to the output terminal of the full wave rectifier; A second capacitor connected in parallel to both LEDs; And a third capacitor connected in parallel to the output terminal of the full wave rectifier.

The apparatus may further include a malfunction preventing part including a fifth resistor and a seventh capacitor connected in parallel between the anode and the gate of the single junction transistor in the relay switching controller.

The AC component filter unit may be connected between the center node of the reference voltage generator and the center node of the comparison voltage generator, and filter the AC component flowing between the center node of the reference voltage generator and the center node of the comparison voltage generator. It includes more.

The apparatus further includes a current limiting unit disposed between the input terminal and the full wave rectifying unit to limit the inrush current.

According to the insulation failure prevention device of the present invention, by measuring the insulation resistance between the line and the earth with a DC voltage can be detected without distinguishing the active line or the neutral line, the maintenance time is shortened, and the good insulation line is normally supplied with power In addition, the poorly insulated line can cut off the power supply along with the alarm, which can improve the convenience of management, minimize the power failure time due to the leakage of the power system, and prevent the accident caused by poor insulation. Can be.

1 is a power supply circuit diagram having an insulation failure blocking device according to an embodiment of the present invention, and
2 is a detailed circuit diagram of a poor insulation blocking apparatus according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the structure and operation | movement of a pulsation shortwave generating apparatus by preferable embodiment of this invention are demonstrated in detail with reference to an accompanying drawing.

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may properly define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, since the embodiments shown in the specification and the configuration shown in the drawings is only one of the most preferred embodiment of the present invention, it is understood that there may be various equivalents and modifications that can replace them at the time of the present application shall.

1 is a power supply circuit having a poor insulation blocking device according to an embodiment of the present invention.

The power supply circuit having a poor insulation blocking device according to an embodiment of the present invention includes an earth leakage breaker 110, a poor insulation blocking device 120, and a load 130.

An earth leakage breaker (110) is disposed between the power supply side and the poor insulation breaker (120).

The poor insulation blocking device 120 is disposed between the output side of the ground fault circuit breaker 110 and the input side of the load 130.

2 is a detailed circuit diagram of a poor insulation blocking apparatus according to an embodiment of the present invention.

Insulation failure blocking device according to an embodiment of the present invention is the input terminal (205-1, 205-2), output terminals (210-1, 210-2), relay contacts (215-1, 215-2), current Limiting unit 220, full-wave rectifying unit 225, alarm unit 230, double voltage unit 235, reference voltage generator 240, comparison voltage generator 245, operating voltage provider 250, relay switching The control unit 255, the AC component filter unit 260, the malfunction prevention unit 265, and the relay switching unit 270 are included.

The input terminals 205-1 and 205-2 are connected to the output side of the earth leakage breaker 110.

The output terminals 210-1 and 210-2 are connected to the input side of the load 130.

The relay contacts 215-1 and 215-2 are disposed between the input terminals 205-1 and 205-2 and the output terminals 210-1 and 210-2, and the relay coils 260 in the relay switching unit 265 ( Switch in response to the operation of RL).

The current limiting unit 220 includes a PTC element and a first capacitor C1 connected in series. The PTC element limits inrush current flowing through the input terminal 205 and prepares for an accident that may occur in the device. In charge of one fuse function, the first capacitor C1 limits the current flowing through the relay coil RL disposed at the rear end and the LED in the alarm unit 230.

The full wave rectifying unit 225 is disposed between the current limiting unit 220 and the neutral line of the input terminals 205-1 and 205-2, and full-wave rectifies an AC voltage applied through the current limiting unit 220.

The alarm unit 230 includes a series connection LED connected in parallel to the output terminal of the full-wave rectifying unit 225, a first zener diode Z1, and a third capacitor C3 directly connected in parallel to the output terminal of the full-wave rectifying unit 235. do. The first zener diode Z1 limits the operation start voltage of the relay charged in the third capacitor C3, and serves to turn off the LED because current does not flow while the operation of the relay is maintained. The third capacitor C3 smoothes the full-wave rectified AC voltage. According to another embodiment of the present invention, a speaker may be used instead of an LED, which will be omitted since it will be apparent to those skilled in the art. According to another embodiment of the present invention, it may further include a second capacitor (C2) connected in parallel across the LED, and serves to bypass the inrush current input to the LED.

The voltage distribution unit 235 is disposed between the other end of the PTC element in the current limiting unit 220 and the neutral line of the input terminal 205, and the input power voltage and the charging voltage charged in the fourth capacitor C4 are added up. The applied back voltage is applied to the fifth capacitor C5 through the fifth diode D5. That is, the AC capacitor charges the fourth capacitor C4 through the sixth diode D6 during the negative half cycle, and the AC voltage and the fourth capacitor C4 through the fifth diode D5 during the positive half cycle. ) Is applied to the fifth capacitor C5.

The reference voltage generator 240 includes first and second resistors R1 and R2 in series connected in parallel with the output terminal of the voltage divider 235, and includes a fifth capacitor C5 in the voltage divider 235. The voltage divider is applied to the back voltage applied to the reference voltage), and the reference voltage VR2 corresponding to the second resistor R2 is applied to the node 2 NR2. Specifically, the first resistor R1 limits the current flowing in the rear end, and the resistance value of the second resistor R2 corresponds to the ground insulation resistance RG reference value.

The comparison voltage generator 245 includes a third resistor R3 and a ground-to-earth insulation resistor RG connected in series with the output terminal of the voltage distribution unit 235. The resistance value of the third resistor R3 is equal to the resistance value of the first resistor R1, and the comparison voltage VRG corresponding to the inter-earth insulation resistance RG is applied to the node G (NRG). Here, it is to be understood that the ground-to-earth insulation resistance RG is not shown in the drawings because it is not implemented in actual device form. The eighth diode D8 prevents current from flowing from the neutral line output terminal 210-2 toward the node G (NRG).

Accordingly, if the actual ground insulation resistance RG is larger than the ground insulation resistance reference value R2, the comparison voltage VRG is higher than the reference voltage VR2, while the ground insulation resistance actual value RG is the ground insulation resistance reference value. If less than R2, the comparison voltage VRG is lower than the reference voltage VR2.

The operation voltage providing unit 250 includes a sixth capacitor C6 and a second zener diode Z2 connected in parallel to the reference voltage generator 240 in series, and the second zener diode Z2 is connected in parallel. The charging voltage charged in the sixth capacitor C6 is determined.

The relay switching controller 255 is configured to output a relay switching control signal when the comparison voltage VRG is higher than the reference voltage VR2. Specifically, the FET connected in parallel between the single junction transistor (UJT) and the photodiode (PD) of the series connection is connected in parallel to the operating voltage providing unit 250, the gate of the single junction transistor (UJT) and the other end of the photodiode, The eighth capacitor C8 and the third zener diode Z3 of the parallel connection coupled between the gate and the drain of the FET and the gate and the source of the FET and a current from node G (NRG) to node 2 (NR2). Includes a seventh diode D7 disposed to flow.

The AC component filter unit 260 includes a fourth resistor R4 and a ninth capacitor C9 in series connected between the node G (NRG) and the node 2 (NR2), and the node G (NRG) and the node. Filter the alternating current flowing between 2 (NR2).

The malfunction prevention unit 265 includes a fifth resistor R5 and a seventh capacitor C 7 connected in parallel between the anode and the gate of the single junction transistor UJT in the relay switching controller 255, and includes a fifth resistor. R5 prevents leakage between the anode and the gate of the single junction transistor UJT, and the seventh capacitor C 7 prevents the single junction transistor UJT from malfunctioning due to noise.

The relay switching unit 270 includes a relay coil RL and a phototriax PT connected in series with the alarm unit 230.

The poor insulation blocking device according to an embodiment of the present invention having such a configuration operates as follows.

i) VRG> VR2

If the actual ground insulation resistance RG is larger than the ground insulation resistance reference value R2, the comparison voltage VRG applied to the node G (NRG) is higher than the reference voltage VR2 applied to the node 2 NR2.

Accordingly, the n-type FET is turned on by being controlled by the charging voltage charged in the eighth capacitor C8. When the n-type FET is turned on and the switching control signal is applied to the gate of the single junction transistor UJT, the single junction transistor UJT is turned on, and the photodiode PD connected in series with the single junction transistor UJT emits light. .

When the phototri solution PT coupled to the photodiode PD in pairs receives the light emission signal of the photodiode PD, the phototri solution PT is turned on and the relay is turned on according to the turn-on of the phototrimer PT. A current flows in the coil RL to close the relay contacts 215-1 and 215-2.

ii) VRG <VR2

If the actual ground insulation resistance RG is smaller than the ground insulation resistance reference value R2, the comparison voltage VRG applied to the node G (NRG) is lower than the reference voltage VR2 applied to the node 2 NR2.

Accordingly, when the n-type FET is turned off and the n-type FET is turned off, the single junction transistor UJT is also turned off, and the photodiode PD connected in series with the single junction transistor UJT does not emit light.

If the phototrie (PT) coupled in pairs with the photodiode (PD) fails to receive the light, current does not flow through the relay coil (RL) connected in series with the phototrie (PT) and thus relay contacts 215-1 and 215-2. ) Is opened, and the power supplied to the load 130 is cut off.

The embodiments and the accompanying drawings described herein are merely illustrative of some of the technical ideas included in the present invention. Therefore, since the embodiments disclosed herein are not intended to limit the technical spirit of the present invention, but to explain, it is obvious that the scope of the technical spirit of the present invention is not limited by these embodiments. Modifications and specific embodiments that can be easily inferred by those skilled in the art within the scope of the technical idea included in the specification and drawings of the present invention should be construed as being included in the scope of the present invention.

110: earth leakage breaker
120: bad insulation blocking device
130: load

Claims (6)

In the insulation failure blocking device comprising an input terminal connected to the power supply side, an output terminal connected to the load side, and a relay contact disposed between the input terminal and the output terminal,
A full-wave rectifier connected in parallel to the input terminal and full-wave rectifying an AC voltage applied through the input terminal;
An alarm unit connected in parallel to an output terminal of the full wave rectifying unit and configured to visually or audibly alert the relay contact during opening;
A double voltage unit connected in parallel to the input terminal and outputting a double voltage of the AC voltage during a positive half cycle of the AC voltage using a plurality of capacitors and a half wave rectifier circuit;
A reference voltage generator including first and second resistors connected in parallel with an output terminal of the double voltage unit and generating a reference voltage applied to the second resistor;
A comparison voltage generator including a third resistor having one end connected to an output terminal of the double voltage unit and generating a comparison voltage applied to the other end of the third resistor;
An operating voltage provider connected in series with the reference voltage generator and including a sixth capacitor and a second zener diode;
The operation voltage is supplied from the operation voltage providing unit, and is connected to the reference voltage generation unit and the comparison voltage generation unit, and configured to output a relay switching control signal when the comparison voltage VRG is higher than the reference voltage VR2. A relay switching control unit;
A relay switching unit connected in parallel with the alarm unit and including a relay coil controlled to the relay switching control signal to open and close the relay contact point; And
An AC component filter unit connected between the center node of the reference voltage generator and the center node of the comparison voltage generator, and filtering an AC component flowing between the center node of the reference voltage generator and the center node of the comparison voltage generator;
Bad insulation blocking device comprising a.
The method of claim 1, wherein the relay switching control unit,
A series junction single junction transistor and a photodiode connected in parallel to the operation voltage providing unit;
A FET connected in parallel between the gate of the single junction transistor and the other end of the photodiode;
An eighth capacitor and a third zener diode of a parallel connection coupled between the gate and the drain of the FET; And
A seventh diode disposed between the gate and the source of the FET
Bad insulation blocking device comprising a.
The method of claim 2,
The alarm unit,
A series connected LED and a first zener diode connected in parallel to the output terminal of the full wave rectifier;
A second capacitor connected in parallel to both LEDs; And
A third capacitor connected in parallel to the output terminal of the full-wave rectifying unit
Bad insulation blocking device comprising a.
The method of claim 3,
And a malfunction prevention part including a fifth resistor and a seventh capacitor connected in parallel between the anode and the gate of the single junction transistor in the relay switching controller.
delete The method of claim 1,
And a current limiting unit disposed between the input terminal and the full wave rectifying unit to limit inrush current.

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