KR101403972B1 - Electric Leakage Circuit Breaker for protecting wrong operation using Pulse Width Modulation - Google Patents

Abstract

The present invention relates to an electric leakage circuit breaker comprising an IC for electric leakage detection, which outputs an ON signal in electric leakage detection by always monitoring the output of a zero phase current transformer used in detection of electric leakage, RF surge, and power surge; and an automatic control unit for preventing electric leakage, for controlling a trip driving unit for cutting off main power. The electric leakage circuit breaker prevents malfunction by ensuring the resistance of the electric leakage circuit breaker with respect to various radiation noise (except RF surge) flowing from the outside to a product and the power surface flowing from the main power and controls the trip driving unit in case of intrinsic electric leakage so as to cut off the main power. Specifically, the electric leakage circuit breaker can be small and prevent the malfunction due to instantaneous electric leakage and noise.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electric leakage circuit breaker,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a malfunction prevention circuit breaker, and more particularly, to a circuit breaker which prevents a malfunction due to a surge current and instantaneous noise.

In general, there are sudden surge voltage / short circuit / electric shock, which is induced by a lightning strike in addition to the actual leakage current, in addition to the actual leakage current.

In addition to the actual leakage current in addition to the actual leakage current, when a surge caused by a lightning strikes the line or flows into the load through the ground, the leakage circuit breaker senses it as a leakage current by a strong electric field and the thyristor outputs a trip signal. So that the electric leakage breaker has a problem of shutting off the power even when the electric leakage is not actual.

The conventional earth leakage breaker operates within a time period of 30 ms or less when the leakage current is detected and is within 0.03 second (30 ms) when the reaction speed is 30 mA for the leakage current interruption, and 0.1 second (100 ms). However, in a place where the power supply is unstable, the trip operation is frequently caused by a very sensitive leakage current and an instantaneous leakage current, and the operation of the load device often stops.

That is, although the instantaneous leakage current of 10 to 20 ms does not greatly affect the load device, the operation of the load device is stopped due to the operation of the leakage circuit breaker.

The cause of such a problem is that once an electrical signal is inputted to a thyristor (SCR) gate of a control signal output unit which generates a control signal for driving a trip driving unit by a signal outputted from an electrical leak detecting unit, even if an electrical signal is short- And it is easy to operate even when a small current is inputted to the gate. Therefore, it is possible to operate the trip driver by influences such as electromagnetic interference (EMI) or electromagnetic interference (EMI) The DETECTOR of the electrical leak detecting unit for detecting and outputting the electrical leakage has a latch characteristic so that the output is maintained even when the electrical leakage is momentary. In a place where the power is unstable, In this case, To.

However, the technical limitations mentioned above are that the leakage current breaker and the instantaneous noise cause the electric leakage breaker to malfunction, and thus the inoperative state of the household and industrial equipments There is a problem that the industrial unmanned equipment causes a serious economic loss when the unmanned industrial equipment causes an inoperable state.

For reference, the methods of other companies' products are as follows.

1. The company M uses a switch switch (relay) to secure the delay time by the operation time of the relay

Problem: Continuously injecting noise and malfunctioning noise longer than Relay operation time

2. A method of analyzing the frequency waveform using a real-time analog analyzer and a surge input analyzer to analyze the frequency of the current by adding a separate image transformer (Z.C.T) to the basic earth leakage breaker.

Problem: It is difficult to miniaturize when using two video deflectors. It is out of the basic of the earth leakage breaker by using main power (front power supply).

3. Using two ICs with leakage current and using switch relay (relay)

Problem: This product has similar function to item 1

SUMMARY OF THE INVENTION The present invention has been developed to solve the above-described problems, and it is an object of the present invention to provide a radio frequency circuit which can prevent malfunction by securing tolerance of an earth leakage breaker against various radiation noise (RF Surge and others) The present invention has been made in view of the above problems, and it is an object of the present invention to provide a malfunction prevention circuit breaker using a PWM method that can cut off the main power by controlling the trip driving unit only in the case of a true fault.

In particular, it is an object of the present invention to provide a malfunction prevention circuit breaker using a PWM method that can be downsized and prevent malfunction due to instantaneous leakage and noise inflow.

According to an aspect of the present invention, there is provided a malfunction prevention circuit breaker using a PWM method,

An IC for leakage detection dedicated to constantly monitoring the output of the video surge generator used for occurrence of a short circuit, an RF surge, and a power surge, and for outputting an ON signal when an electrical leak is detected; A phase detector for detecting a phase of the output signal of the electrical leak detecting unit for notifying the current state of the IC for leakage detection to a zero crossing of the image current transformer, and the output signal of the leakage current detector is compared with the output signal of the current transformer and the main power output signal in accordance with the amount of leakage, An output signal of the leakage current detection dedicated IC, an output signal of the video current transformer, And a phase period between the output signal of the leakage detecting portion and the output signal of the phase transformer and the main power output signal of which the phase period is changed according to the amount of leakage A frequency sensing unit for converting a frequency of the main power source to a sine-multiple frequency, and a frequency-sensing unit for sensing an ON period section of the first signal of the conversion unit by the frequency sensing unit And a control unit for counting the main power source signal converted into the sine drain frequency and outputting a trip signal indicating the true leakage current when the counted number is greater than or equal to the set number to the electrical leakage blocking automatic control unit do.

The present invention can prevent a malfunction by securing immunity of an earth leakage breaker against various radiation noise (RF Surge outside) and a power surge introduced from a main power source to the product from the outside, The main power can be cut off.

Particularly, miniaturization is possible and malfunction due to instantaneous leakage and noise inflow can be prevented.

1 is a view showing a configuration of a malfunction prevention circuit breaker using a PWM method according to the present invention;

1 is a diagram illustrating a configuration of a malfunction prevention earth leakage breaker using a PWM method according to the present invention.

As shown in FIG. 1, the malfunction-preventing earth leakage breaker using the PWM method according to the present invention can be applied to various products such as various radio frequency (RF) surges introduced into the product and power surges introduced from the main power source, (220V / 60Hz) and a current transformer (ZCT) that are built in the earth leakage breaker, which is built in the earth leakage breaker, ) Driving unit.

Therefore, the basic function of the current circuit breaker (main power cut-off, image current transformer, leakage current detection, etc.) is performed, and various radiation noise (RF surge, etc.) And to prevent the malfunction by securing the resistance of the earth leakage breaker to the power surge flowing from the main power source.

Specifically, as shown in Fig. 1, there is provided an IC for detecting an electrical leak, which is provided with a dedicated IC for monitoring an output of a video current transformer used at the time of occurrence of a short circuit, RF surge, or power surge, (101) for outputting a current state signal of the IC for detecting an electrical leak, characterized by comprising: an electrical leak detecting portion (101) for outputting a current state signal of the IC for detecting an electrical leak, The phase difference between the output signal of the leakage detection unit and the phase of the output signal of the phase difference detection unit is converted into a PWM signal according to the detected amount of leakage according to the degree of deviation from the zero crossing of the image current transformer, An output signal of the phase error detecting IC is compared with an output signal of the phase error detecting IC, And outputting the first signal when the phase difference between the output signal of the phase transformer and the main power output signal is different from the output signal of the phase transformer and the output signal of the phase transformer, A frequency detector 103 for converting a frequency of the main power source to a sine wave frequency, and a frequency converter 103 for converting the frequency of the main power source to a frequency of the sine wave, ) Synchronized with the main power supply signal converted by the frequency sensing unit 103 to the sine-drain frequency, and when the counted number is greater than or equal to the set number, And a control unit (104) for outputting a trip signal to the automatic electrical shutdown control unit.

(In the present invention, the current state of the IC for leakage detection only refers to a state in which the IC output for leakage detection is outputted because it is in a state of leakage.) In other words, The present invention is a condition for discriminating an intrinsic short circuit, and it is assumed that the IC output for detecting the short circuit is in an ON state, that is, a short circuit state. The IC for leakage detection only monitors the output of a video current transformer that is used at the time of occurrence of leakage current, RF surge, and power surge, and outputs an ON signal when an electric leakage is detected. The dedicated IC can be used as it is. For reference, the feature of this device is to use the output of the leakage current detection IC by using the current transformer (Z.C.T) and the IC for leakage detection as it is, which is the basic of the commercial circuit breaker.

The converter 102 converts the phase period of the output signal of the leakage detecting unit 101, which indicates the current state of the IC for detecting an electrical leak, by the amount of leakage determined according to the degree of deviation from the zero crossing of the image current transformer, (For reference, the present invention uses the principle that the phase of the output signal of the ZCT is varied to generate a difference from the phase of the main power source during the true leakage), and the phase period is changed according to the amount of leakage And compares the output signal of the leakage detecting unit 101 with the output signal of the video current transformer and the main power output signal. Therefore, when the output signal of the IC for leakage detection is different from the phase period of the output signal of the phase transformer and the phase of the main power output signal, a first signal (e.g., High) is output. And outputs a second signal (e.g., Low) when the phase of the output signal of the electrical leak detecting unit 101 is the same as the phase of the output signal of the video current transformer and the main power output signal.

The frequency sensing unit 103 converts the frequency of the main power source (220 V / 60 Hz) supplied from the KEPCO to a sine-wave frequency (for example, 220 V / 120 Hz). This is to improve the leakage current accuracy because the trip time of the earth leakage breaker should be within 30ms, but it is 32ms at 60Hz.

The control unit 104 synchronizes the ON signal period of the first signal of the conversion unit 102 with the main power signal converted into the sine wave frequency by the frequency sensing unit 103 and outputs the counted When the number or value is equal to or greater than the set number, a trip signal indicative of an intrinsic short circuit is outputted to the automatic electrical shutdown prevention control unit. The automatic electrical shutdown control unit controls the trip driving unit for shutting off the main power.

Hereinafter, the operation of the malfunction-preventing earth leakage breaker using the PWM method according to the present invention shown in FIG. 1 will be described.

First, the electrical leak detecting portion 101 outputs the present state signal of the electrical leak detecting IC.

That is, the output value of an IC for detecting an electrical leak detecting only at all times, such as an occurrence of a short circuit, an RF surge, a power surge, and the like, which always detects the output of the ZCT, is notified to the converting unit 102 The present invention can be applied to the case where the IC output for leakage detection only is ON, that is, the leakage current is already present As a condition thereof.

For reference, the leakage detection dedicated IC constantly monitors the output of a video current transformer used when an electric leakage occurs, an RF surge, or a power surge, and outputs an ON signal when an electrical leak is detected.

Next, the converting unit 102 converts the phase period of the output signal of the electric leakage detecting unit 101, which indicates the current state of the IC for detecting an electric leakage, to the amount of leakage determined according to the degree of deviation from the zero crossing of the image current transformer (Note that the present invention is based on the principle that the phase of the output signal of the ZCT is varied to generate a difference from the phase of the main power.

Then, the output signal of the leakage detection unit 101, whose phase period has been converted in accordance with the amount of leakage, is compared with the output signal of the video current transformer and the main power output signal.

Therefore, when the output signal of the IC for leakage detection is different from the phase period of the output signal of the phase transformer and the phase of the main power output signal, a first signal (e.g., High) is output. And outputs a second signal (e.g., Low) when the phase of the output signal of the electrical leak detecting unit 101 is the same as the phase of the output signal of the video current transformer and the main power output signal.

On the other hand, the frequency sensing unit 103 converts the frequency of the main power (220 V / 60 Hz) supplied from the KEPCO into a soul-multiple frequency (220 V / 120 Hz, for example) This is to improve the leakage current accuracy because the trip time of the earth leakage breaker should be within 30ms, but it is 32ms at 60Hz.

Next, the control unit 104 synchronizes the ON signal period of the first signal of the conversion unit 102 with the main power signal converted into the sine-wave frequency by the frequency sensing unit 103, And when the counted number is equal to or greater than the set number, outputs a trip signal indicating the intrinsic leakage current to the electric leakage blocking automatic control unit.

Then, the above-described automatic control unit for preventing electric leakage prevents malfunction by securing the resistance of the earth leakage breaker against various radiation noise (RF Surge outside) and power surge introduced from the main power source from outside due to malfunction. And the main driving power can be shut off by controlling the trip driving unit only in the case of an intrinsic short circuit.

As a result, it is possible to prevent the malfunction due to the instantaneous leakage and the noise inflow.

Description of the Related Art [0002]
101: electric leak detecting section 102:
103: Frequency sensing unit 104: Control unit

Claims (1)

An IC for leakage detection dedicated to constantly monitoring the output of the video surge generator used for occurrence of a short circuit, an RF surge, and a power surge, and for outputting an ON signal when an electrical leak is detected; In the earth leakage breaker,
An electrical leak detecting section for outputting a current state signal of the electrical leak detecting IC;
Wherein the phase period of the output signal of the electrical leak detecting section for notifying the current state of the IC for leakage detection is PWM-converted according to the amount of leakage determined according to the degree of deviation from the zero crossing of the image current transformer, The phase difference between the output signal of the leakage current detection dedicated IC and the output signal of the phase error detection unit and the phase of the main power output signal by comparing the output signal of the leakage detection unit with the output signal of the leakage current detection unit, And outputs the first signal when the phases are different from each other, and when the phase difference between the output signal of the electrical leak detecting portion and the output signal of the phase transformer and the main power output signal, A converter for outputting a second signal;
A frequency sensing unit for converting a frequency of the main power source into a sine-drain frequency; And
Wherein the on period period of the first signal of the conversion unit is synchronized with the main power supply signal converted to the sine wave frequency by the frequency sensing unit, and when the counted number is greater than or equal to the set number, And a control unit for outputting a signal to the electrical leakage preventing automatic control unit.

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