KR101616797B1 - Earth leakage circuit breaker - Google Patents

Abstract

The present invention relates to an earth leakage breaker, and more particularly, to a noise elimination circuit for discriminating noise components due to switching noise or harmonic components included in a leakage current signal through a discrimination signal generated by following a leakage signal, It is possible to accurately discriminate the leakage current signal applied to the leakage current circuit breaker and to accurately determine whether or not the circuit breaker is operated for the leakage current signal applied to the leakage current circuit breaker and to prevent the malfunction of the leakage current circuit breaker caused by the noise signal similar to the leakage current signal The present invention relates to an earth leakage breaker having an effect that can be achieved.

Description

{EARTH LEAKAGE CIRCUIT BREAKER}

The present invention relates to an earth leakage breaker, and more particularly, to an earth leakage breaker capable of determining whether a leakage signal includes a harmonic through a discrimination signal generated by following a leakage signal applied to the breaker, and operating the earth leakage breaker.

1 is a block diagram showing a flow of interruption operation of a conventional earth leakage breaker.

The conventional earth leakage breaker which operates in the order shown in FIG. 1 is amplified by an amplifier when a leakage current signal is detected through a zero current transformer (ZCT). The amplified leakage signal is compared with the reference voltage set by the level discriminator, and when it is larger than the reference voltage, the trip generator transmits the trip signal to the trip unit. The trip circuit breaks the power supply circuit and protects the load and the human body in the event of a short circuit.

In the conventional earth leakage breaker, no malfunction occurs in a linear load with no noise or distortion. However, most current electronic and electrical appliances use alternating current (AC) power instead of alternating current (DC). In this conversion process, the switching device is used to increase the efficiency. Due to this switching action, the original pure AC signal is noisy and the signal is distorted. That is, the harmonic components due to the switching noise and the signal distortion are generated in the conventional art in which the phase difference is generated in the AC signal even when the leakage signal is not generated, It is a main cause of malfunction that the tripping, that is, the power supply is interrupted by the harmonic component.

Therefore, in the present specification, the noise component due to the switching noise or the harmonic components included in the leakage current signal is discriminated through the discrimination signal generated by following the leakage current signal to perform a blocking operation, thereby preventing malfunction due to noise Which can be used as a circuit breaker.

A leakage circuit breaker disclosed in this specification for realizing the above-mentioned problems includes a trip coil for blocking a line, a detection unit for detecting a leakage signal in the line, a signal generation unit for generating a determination signal in accordance with the leakage signal, And a control unit for controlling the operation of the trip coil according to a result of the determination.

In one embodiment, the detection unit may include a zero-current transformer (ZCT) for detecting the leakage signal and an amplifier for amplifying the detected leakage signal.

In one embodiment, the determination signal may be generated by following the leakage signal according to time.

In one embodiment, the determination signal may be generated in the form of a pulse width modulation (PWM) signal.

In one embodiment, the determination signal may be a combination of a LOW pulse and a HIGH pulse.

In one embodiment, the signal generator includes a charge / discharge circuit, wherein the determination signal can be generated by an output signal of the charge / discharge circuit following the leakage signal.

In one embodiment, the signal generator includes: a first voltage discriminator for comparing the leakage signal and the output signal with a predetermined first reference voltage to cause the charge / discharge circuit to be charged; A second voltage discriminator for comparing the first reference voltage with a predetermined second reference voltage to generate a signal for the comparison result, and generating either the HIGH pulse or the LOW pulse according to the signal of the comparison result, Discharge circuit is opened when the HIGH pulse is applied from the pulse generator so that the charge / discharge circuit is discharged, and when the LOW pulse is applied, the charge / discharge circuit is charged Wherein the output signal includes a first voltage signal and a second voltage signal, Groups may be negative-feedback (Feedback).

In one embodiment, the first reference voltage may be a minimum reference voltage that is a reference for interrupting operation of the earth leakage breaker, and the second reference voltage may be a minimum reference voltage that is a minimum output reference of the charge / discharge circuit.

In one embodiment, the first voltage discriminator may cause the charge / discharge circuit to be charged such that the output signal is equal to the magnitude of the leakage current signal when the leakage signal is larger than the first reference voltage.

In one embodiment, the second voltage discriminator generates a rising signal (Vr) that causes the output signal to decrease when the output signal becomes equal to the leakage current signal, , It is possible to generate a falling signal Vf to increase the output signal.

In one embodiment, the pulse generator may generate the HIGH pulse when the rising signal is generated, and may generate the LOW pulse when the falling signal is generated.

In one embodiment, the reference signal may be generated by following a pure leakage signal not including the noise.

In one embodiment, the control unit may compare the period and the pulse width of the determination signal with the period and the pulse width of the reference signal.

In one embodiment, the controller may control the trip coil to operate when the determination signal matches the reference signal.

In one embodiment, when the determination signal is not coincident with the reference signal, the controller may determine that the noise is contained in the leakage signal, and control the trip coil to be inoperative.

In one embodiment, the controller may determine the magnitude of the leakage signal by the magnitude of the period and the pulse width of the determination signal, and may control the operation time of the trip coil according to the magnitude of the leakage signal.

In one embodiment, when the magnitude of the leakage current signal is larger than the magnitude of the reference signal, the controller can shorten the operation time of the trip coil.

The earth leakage breaker disclosed in this specification has an effect of making it possible to discriminate the leakage signal applied to the earth leakage breaker with high accuracy by judging whether or not noise is included in the leakage signal through the discrimination signal generated by following the leakage signal.

The leakage circuit breaker disclosed in this specification has an effect of accurately discriminating whether or not a shutdown operation is performed with respect to a leakage current signal applied to an earth leakage breaker by determining whether noise is included in the leakage current signal through the determination signal generated by following the leakage current signal .

The leakage circuit breaker disclosed in this specification has an effect of preventing erroneous operation of the earth leakage breaker caused by a noise signal in a form similar to that of the leakage signal by judging whether or not the leakage signal includes noise through the discrimination signal generated by following the leakage signal have.

The leakage circuit breaker disclosed in this specification can prevent unnecessary operation of the earth leakage breaker due to the noise signal by determining whether or not the noise of the earth leakage signal is included through the discrimination signal generated by following the earth leakage signal to increase the mechanical life of the earth leakage breaker .

The leakage circuit breaker disclosed in this specification determines whether noise is included in the leakage signal through the discrimination signal generated by following the leakage signal and thereby prevents unnecessary operation of the leakage circuit breaker caused by the noise signal, As shown in Fig.

The leakage circuit breaker disclosed in this specification has an effect of performing an appropriate shut-off operation according to the degree of the electric leakage state by performing the shut-off operation in accordance with the determination signal generated by following the electric leakage signal.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram showing a flow of a blocking operation of a conventional earth leakage breaker; Fig.
2 is a block diagram showing a configuration of an earth leakage breaker disclosed in this specification;
3 is a configuration diagram showing a configuration according to an embodiment of the earth leakage breaker disclosed in this specification;
4 is a configuration diagram showing a configuration of a signal generator according to an embodiment of the earth leakage breaker disclosed in this specification;
5 is a block diagram showing a specific flow of a leakage signal follow-up and discrimination signal generation according to an embodiment of the earth leakage breaker disclosed in this specification.
6 is a waveform chart showing a follow-up type of an earth leakage signal according to an embodiment of the earth leakage breaker disclosed in this specification.
Fig. 7 is a waveform diagram showing a generation form of the discrimination signal according to the embodiment of the earth leakage breaker disclosed in this specification; Fig.
8 is a waveform chart showing a follow-up type of an earth leakage signal according to an embodiment of the earth leakage breaker disclosed in this specification;
9 is a waveform chart showing a generation form of the discrimination signal according to the embodiment of the earth leakage breaker disclosed in this specification.

The technique disclosed in this specification can be applied to an earth leakage breaker. However, the technology disclosed in this specification is not limited thereto, and can be applied to all relays, circuit breakers, controllers, switches, power protection devices, and other protection relay systems to which the technical idea of the above-described technology can be applied.

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the scope of the technology disclosed herein. Also, the technical terms used herein should be interpreted as being generally understood by those skilled in the art to which the presently disclosed subject matter belongs, unless the context clearly dictates otherwise in this specification, Should not be construed in a broader sense, or interpreted in an oversimplified sense. In addition, when a technical term used in this specification is an erroneous technical term that does not accurately express the concept of the technology disclosed in this specification, it should be understood that technical terms which can be understood by a person skilled in the art are replaced. Also, the general terms used in the present specification should be interpreted in accordance with the predefined or prior context, and should not be construed as being excessively reduced in meaning.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. In this specification, the terms "comprising ", or" comprising ", etc. should not be construed as necessarily including the various elements or steps described in the specification, Or may be further comprised of additional components or steps.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals denote like or similar elements, and redundant description thereof will be omitted.

Further, in the description of the technology disclosed in this specification, a detailed description of related arts will be omitted if it is determined that the gist of the technology disclosed in this specification may be obscured. It is to be noted that the attached drawings are only for the purpose of easily understanding the concept of the technology disclosed in the present specification, and should not be construed as limiting the spirit of the technology by the attached drawings.

Hereinafter, the configuration of the earth leakage breaker disclosed in this specification will be described with reference to Fig.

2 is a block diagram showing the configuration of the earth leakage breaker disclosed in this specification.

2, the earth leakage breaker 50 includes a trip coil 10, a detection unit 20, a signal generation unit 30, and a control unit 40.

The earth leakage breaker (50) may be connected to a line through which electricity flows.

The earth leakage breaker (50) can protect the load connected to the line and the line from an overcurrent and a leakage current.

The overcurrent may mean either an overload current or a short-circuit current.

The leakage current may refer to a current flowing through an insulator such as paper, rubber, mica, glass, and the like.

The leakage circuit breaker (50) may block the line to protect the line and the load connected to the line when the leakage current flows.

The trip coil (10) can block the line.

The trip coil 10 can block the line by performing a trip operation in which a contact connected to the line is opened by an electromagnetic force.

The trip coil 10 may be operated to shut off the line by a trip signal generated by the control unit 40. [

The trip signal may mean a signal for controlling the operation of the trip coil 10 so that the line is blocked corresponding to the leakage signal.

The detecting section (20) can detect the leakage current signal from the line.

The detecting unit 20 may sense the leakage current generated in the line and detect the leakage signal corresponding thereto.

The detection unit 20 can transmit the leakage signal detected by the line to the signal generation unit 30.

The signal generator 30 can generate the discrimination signal by following the leakage current signal.

The discrimination signal may be a signal that is a basis for judging whether or not the line is short-circuited.

The discrimination signal can be generated by following the change of the magnitude and the frequency of the leakage signal.

The control unit 40 may compare the determination signal with a reference signal to determine whether or not the leakage current signal includes noise, and control the operation of the trip coil according to the determination result.

Hereinafter, an embodiment of the earth leakage breaker disclosed in this specification will be described with reference to Figs. 3 and 4. Fig.

3 is a configuration diagram showing a configuration according to an embodiment of the earth leakage breaker disclosed in this specification.

4 is a block diagram showing a configuration of a signal generator according to an embodiment of the earth leakage breaker disclosed in this specification.

3, the earth leakage breaker 50 includes the trip coil 10, the detection unit 20, the signal generation unit 30, and the control unit 40, As shown in FIG.

The trip coil 10 may be connected to the line so that the line can be cut off.

The trip coil 10 can cut off the line by making the trip operation by the trip signal when the leakage current occurs.

The detection unit 20 may be connected to the line to detect the leakage current and detect the leakage current signal.

The detection unit 20 may include a zero current transformer (ZCT) 21 for detecting the leakage current signal and an amplifier 22 for amplifying the detected leakage current signal.

The leakage current signal can be detected through the video current transformer 21.

The image deflector 21 detects a zero-phase sequence current flowing through the line and can easily change the size of the image current.

The amplifier (22) can amplify the detected leak signal in a form easy to measure.

The detected leakage signal is amplified by the amplifier 22, so that the leakage signal can be easily tracked.

The leakage current signal detected through the video current transformer 21 of the detector 20 and amplified through the amplifier 22 can be transmitted to the signal generator 30.

The signal generator 30 may generate the discrimination signal by following the leakage current signal.

The determination signal may be generated by following the leakage signal according to time.

The determination signal may be generated in the form of a pulse width modulation (PWM) signal.

The determination signal may be a combination of a LOW pulse and a HIGH pulse.

As shown in FIG. 4, the signal generator 30 may include a charge / discharge circuit 31. FIG.

The charge / discharge circuit 31 may be charged / discharged by the signal generation unit 30. FIG.

The signal generating unit 30 includes the charge / discharge circuit 31, and the determination signal can be generated by the output signal of the charge / discharge circuit 31 following the leakage current signal.

That is, the determination signal can be generated on the principle that the output signal following charging and discharging of the charging and discharging circuit 31 follows the leakage current signal.

The charge / discharge circuit 31 can increase the output signal when charged.

The charge / discharge circuit 31 can reduce the output signal when discharged.

That is, the output signal is increased when the charge / discharge circuit 31 is being charged, and may be decreased when the charge / discharge circuit 31 is discharging, so that the output signal may follow the leakage signal.

As the output signal follows the leakage signal while repeating increase and decrease, the discrimination signal can also be generated in the form of repeating two types of signals corresponding to increase and decrease.

The signal generator 30 further includes a first voltage discriminator 32, a second voltage discriminator 33, a pulse generator 34 and a switch 35, (Feedback) to the second voltage discriminator 33 until the follow-up to the second voltage discriminator 33 is completed.

The signal generator 30 further includes the first voltage discriminator 32 for comparing the leakage signal and the output signal with a predetermined first reference voltage to cause the charge / discharge circuit 31 to be charged can do.

The first reference voltage may be a minimum reference voltage that is a blocking operation reference of the earth leakage breaker (50).

For example, when the earth-leakage circuit breaker 50 operates at a leakage current of 10 [V], the first reference voltage may be 10 [V].

The first voltage discriminator 32 may charge the charge / discharge circuit 31 when the leakage signal and the output signal are greater than the first reference voltage.

That is, the first voltage discriminator 32 allows the charge / discharge circuit 31 to be charged when the leakage signal and the output signal are equal to or higher than the minimum reference voltage of the earth leakage breaker 50, So that it can follow the leakage current signal.

The signal generating unit 30 may further include the second voltage discriminator 33 for comparing the output signal with the leakage current signal and a predetermined second reference voltage to generate a signal for comparison result .

The second reference voltage may be a minimum reference voltage which is a minimum output reference of the charge / discharge circuit 31.

For example, when the minimum output reference of the charge / discharge circuit 31 is 5 [V], the second reference voltage may be 5 [V].

The second voltage discriminator 33 may generate a signal for charging / discharging the charge / discharge circuit 31 when the output signal has the same magnitude as the leakage current signal and the predetermined second reference voltage have.

The second voltage discriminator 33 may generate a rising signal Vr that causes the output signal to decrease when the output signal becomes equal to the leakage current signal.

That is, the second voltage discriminator 33 is configured such that the charge / discharge circuit 31 is charged by the first voltage discriminator 32 to increase the output signal, The charging / discharging circuit 31 may be discharged to generate the rising signal Vr to decrease the output signal.

When the output signal becomes equal to the second reference voltage, the second voltage discriminator 33 may generate a falling signal Vf to increase the output signal.

That is, the second voltage discriminator 33 may be configured such that the charge / discharge circuit 31 is discharged by the rising signal Vr, and the output signal is reduced so that the output signal is smaller than the second reference voltage The charging / discharging circuit 31 may be charged to generate the falling signal Vf to increase the output signal.

The signal generator 30 generates either the HIGH pulse or the LOW pulse according to the signal of the comparison result of the second voltage discriminator 33 to generate the discrimination signal. ).

The pulse generator 34 generates either the HIGH pulse or the LOW pulse according to the signal generated by the second voltage discriminator 33 so that the discrimination result of the combination of the HIGH pulse and the LOW pulse So that a signal can be generated.

The pulse generator 34 generates the HIGH pulse when the rising signal Vr is generated by the second voltage discriminator 33 and outputs the LOW pulse when the falling signal Vf is generated Can be generated.

That is, when the rising signal Vr is generated by the second voltage discriminator 33 because the output signal becomes equal to the leakage current signal, the pulse generator 34 outputs the rising signal Vr, Signal is increased and becomes equal to the leakage current signal, and the output signal becomes equal to the second reference voltage so that the second voltage discriminator 33 generates the falling signal Vf The LOW pulse indicating that the output signal following the leakage current signal is reduced to become equal to the second reference voltage is generated so that the determination signal comprising the combination of the HIGH pulse and the LOW pulse is generated .

The signal generator 30 is connected to the charge / discharge circuit 31. When the HIGH pulse is applied from the pulse generator 34, the signal generator 30 causes the charge / discharge circuit 31 to discharge, And a switch (35) for closing the charge / discharge circuit (31) when the pulse is applied.

That is, when the HIGH pulse indicating that the output signal is increased to become equal to the leakage current signal is generated, the switch 35 is opened to discharge the charge / discharge circuit 31 so that the output signal is reduced, When the LOW pulse indicating that the output signal is reduced to be equal to the second reference voltage is generated, the charge / discharge circuit 31 may be closed so that the output signal is increased.

3, the controller 40 compares the determination signal with the reference signal to determine whether or not the leakage current signal contains the noise, and controls the operation of the trip coil 10 according to the determination result The reference signal may be generated by following a pure leak current signal that does not include the noise.

That is, the reference signal is generated following the pure leak signal not including the noise, so that when the discrimination signal is generated by following the leak signal including the noise, the reference signal is a reference for determining whether the noise is included in the leakage signal .

Here, the pure water leakage signal may be in the form of a leakage signal that is a basis for operating the leakage current interruption in the conventional leakage circuit breaker, that is, the reference signal may be a leakage current signal It may be generated by following.

The control unit 40 may compare the period and the pulse width of the discrimination signal with the period and pulse width of the reference signal.

Since the reference signal is generated following the pure water leakage signal, the period and the pulse width of the reference signal indicate the period and the pulse width of the pure water leakage signal. Therefore, the determination signal follows the leakage signal including the noise It is possible to determine whether or not the leakage current signal includes the noise by comparing the period and pulse width of the reference signal with the period and pulse width of the discrimination signal.

The control unit 40 may control the trip coil 10 to operate when the determination signal matches the reference signal.

Since the determination signal coincides with the reference signal, it means that the leakage signal is the pure water leakage signal. Therefore, when the determination signal is coincident with the reference signal, The trip coil 10 may be controlled so that the line is blocked.

The control unit 40 may determine that the noise is contained in the leakage signal and control the trip coil 10 not to operate if the determination signal is not coincident with the reference signal.

If the determination signal does not coincide with the reference signal, it means that the leakage signal includes the noise and that the leakage signal is not the pure leakage signal. Therefore, when the determination signal is not coincident with the reference signal , The control unit (40) can control the trip coil (10) not to operate so that the line is not blocked with respect to the leakage current signal.

The control unit 40 may determine the magnitude of the leakage signal by the magnitude of the period and the pulse width of the determination signal and may control the operation time of the trip coil 10 according to the magnitude of the leakage signal.

Since the determination signal is generated following the leakage signal, the controller 40 determines the magnitude of the leakage signal through the magnitude of the period and the pulse width of the determination signal, The operation time can be controlled.

The control unit 40 may determine the size of the leakage signal and shorten the operation time of the trip coil 10 when the leakage signal is larger than the reference signal.

When the magnitude of the leakage signal is larger than the magnitude of the reference signal, it means that the leakage signal is larger than the pure leakage signal, which means that the leakage signal is more dangerous than the pure leakage signal. The control unit 40 may shorten the operation time of the trip coil 10 because the shutdown operation time for the signal needs to be cut off earlier than the shutdown operation time for the signal.

For example, when the shutdown time for the pure leak signal is 0.1 [s], if the size of the leakage signal is larger than the size of the reference signal, the controller 40 controls the trip coil 10 The operation time of the trip coil 10 can be shortened to 0.1 [s] or less so as to operate faster than the shutdown operation time of 0.1 [s] for the pure water leakage signal.

Hereinafter, with reference to FIG. 5, a specific flow of the leakage signal follow-up and determination signal generation of the earth leakage breaker disclosed in this specification will be described with reference to FIGS. 6 to 9. FIG.

5 is a block diagram showing a specific flow of leakage signal follow-up and discrimination signal generation according to the embodiment of the earth leakage breaker disclosed in this specification.

Fig. 6 is a waveform diagram 1 showing a follow-up type of a leakage current signal according to an embodiment of the earth leakage breaker disclosed in this specification. Fig.

Fig. 7 is a waveform diagram 1 showing a generation form of the discrimination signal according to the embodiment of the earth leakage breaker disclosed in this specification. Fig.

Fig. 8 is a waveform diagram 2 showing a follow-up type of the leakage current signal according to the embodiment of the earth leakage breaker disclosed in this specification.

Fig. 9 is a waveform diagram 2 showing a generation form of the discrimination signal according to the embodiment of the earth leakage breaker disclosed in this specification. Fig.

As in the flow shown in FIG. 5, the earth leakage breaker 50 can detect the earth leakage signal Vin from the line through the ZTC transformer 21.

The leakage current signal Vin detected by the ZCT 21 may be amplified by the amplifier 22 and transmitted to the first voltage discriminator 32. [

The first voltage discriminator 32 compares the magnitude of the amplified leakage signal Vamp and the output signal Vch of the charging and discharging circuit 31 with the minimum reference voltage of the earth leakage breaker 50 1 reference voltage Vref_A.

When the amplified leakage signal Vamp is larger than the first reference voltage Vref_A, the first voltage discriminator 32 determines that the amplitude of the output signal Vch is smaller than the amplitude of the amplified leakage signal Vamp The charge / discharge circuit 31 can be charged so as to be equal to the size of the charge / discharge circuit 31.

When the amplified leakage signal Vamp is larger than the first reference voltage Vref_A, the first voltage discriminator 32 closes the switch 35 so that the charge / discharge circuit 31 is charged .

Thereafter, the output signal Vch is fed back to the second voltage discriminator 33 so that the magnitude of the output signal Vch in the second voltage discriminator 33 is smaller than the amplified leakage current signal Vamp ) And the second reference voltage (Vref_B) which is the minimum output voltage of the charge / discharge circuit (31).

6, the second voltage discriminator 33 compares the magnitude of the negative feedback signal Vch with the magnitude of the amplified leakage current signal Vamp and the magnitude of the second reference voltage Vref_B The charge / discharge circuit 31 is discharged to reduce the output signal Vch when the output signal Vch becomes equal to the amplified leakage signal Vamp.

When the output signal Vch becomes equal to the amplified leak current signal Vamp, the second voltage discriminator 33 opens the switch 35 so that the charge / discharge circuit 31 is discharged The pulse generator 34 generates the HIGH pulse so that the pulse generator 34 generates the HIGH pulse so that the pulse generator 34 generates the HIGH pulse accordingly, HIGH pulses can be added.

Thereafter, the output signal Vch is fed back to the second voltage discriminator 33 so that the magnitude of the output signal Vch from the second voltage discriminator 33 is amplified by the amplified leakage current signal Vamp and the second reference voltage Vref-B.

The second voltage discriminator 33 compares the magnitude of the output signal Vch that has been re-fed back with the magnitude of the amplified leakage signal Vamp and the second reference voltage Vref_B, When the signal Vch becomes equal to the second reference voltage Vref_B, the charge / discharge circuit 31 may be charged again so that the output signal Vch may be increased again.

When the output signal Vch becomes equal to the second reference voltage Vref_B, the second voltage discriminator 33 closes the switch 35 to charge the charge / discharge circuit 31 again, The pulse generator 34 generates the falling pulse signal Vf so that the pulse generator 34 generates the LOW pulse and the pulse generator 34 generates the LOW pulse accordingly, The LOW pulse may be added.

Thereafter, the output signal Vch may be negatively fed back to the second voltage discriminator 33, and the process may be repeated until the amplified leakage signal Vamp is followed .

The discrimination signal PWM generated by repeating the above process can be expressed in the form of the waveform shown in FIG.

7, the discrimination signal PWM comprises the HIGH pulse when the rising signal Vr is generated, and the HIGH pulse when the falling signal Vf is generated, Type PWM signal.

The determination signal PWM shown in FIG. 7 is a waveform that follows the pure water leakage signal, and such a waveform may be the same as the shape of the reference signal.

That is, the reference signal has the same waveform as the discrimination signal PWM shown in FIG. 7, and the discrimination signal PWM judges whether or not the noise of the leakage signal of the earth leakage breaker 50 is included The reference signal may be the reference signal.

On the other hand, the waveform shown in FIG. 8 shows the waveform of the leakage signal in the case where the noise is included, and the waveform generated as a result of such tracking can be the same as the PWM waveform shown in FIG.

That is, the PWM waveform shown in FIG. 9 may be the discrimination signal to be discriminated by the earth leakage breaker 50.

That is, the discrimination signal shown in FIG. 7 shows the waveform of the reference signal generated by following the pure leakage signal, and the discrimination signal shown in FIG. 9 shows the form of the discrimination signal to be discriminated to be compared with the reference signal will be.

The PWM waveform shown in FIG. 9 is different from the waveform generated in the form following the pure leak signal, and has a period and a width different from each other. When the PWM waveform is compared with the period and width of the reference signal, It is possible to judge whether noise is contained or not.

5, the discrimination signal PWM generated by the above process is transmitted to the controller 40, and the controller 40 compares the period and the pulse width of the discrimination signal PWM with the noise It is possible to determine whether or not the noise is included in the leakage signal Vin by comparing the period and the pulse width of the reference signal generated by following the pure leakage signal that is not included.

The control unit 40 may control the trip coil 10 to operate when the determination signal PWM coincides with the reference signal. If the determination signal PWM does not match the reference signal , It is determined that the noise is included in the leakage signal Vin so that the trip coil 10 is not operated so that the leakage circuit breaker 50 with respect to the leakage signal Vin is shut off .

The control unit 40 determines the magnitude of the leakage signal Vin based on the magnitude of the period and the pulse width of the determination signal PWM and controls the trip coil 10 For example, when it is determined that the magnitude of the earth leakage signal Vin is larger than the magnitude of the reference signal, the operating time of the trip coil 10 is shortened, The protection can be performed more quickly and stably.

Embodiments of the earth leakage breaker disclosed in this specification can be implemented by being applied to an earth leakage breaker that operates by detecting a leakage signal.

Embodiments of the earth leakage breaker disclosed in this specification can be implemented by being applied to an electronic relay including a mechanical type and a digital type.

Embodiments of the earth leakage breaker disclosed in this specification can be applied to an earth leakage breaker including a relay, a switch, a controller, and a protection device for electric power.

Embodiments of the earth leakage breaker disclosed in this specification can be implemented by being applied to a water power transmission facility including a relay and a breaker, and a water supply system.

Embodiments of the earth leakage breaker disclosed herein can be applied to a customer's protective relay system including relays and breakers.

Embodiments of the earth leakage breaker disclosed in this specification can be implemented by applying a method of tracking an electrical leakage signal and a method of generating a determination signal in a software manner and can also be implemented in one or more combinations of the embodiments .

The earth leakage breaker disclosed in this specification has an effect of making it possible to discriminate the leakage signal applied to the earth leakage breaker with high accuracy by judging whether or not noise is included in the leakage signal through the discrimination signal generated by following the leakage signal.

The leakage circuit breaker disclosed in this specification has an effect of accurately discriminating whether or not a shutdown operation is performed with respect to a leakage current signal applied to an earth leakage breaker by determining whether noise is included in the leakage current signal through the determination signal generated by following the leakage current signal .

The leakage circuit breaker disclosed in this specification has an effect of preventing erroneous operation of the earth leakage breaker caused by a noise signal in a form similar to that of the leakage signal by judging whether or not the leakage signal includes noise through the discrimination signal generated by following the leakage signal have.

The leakage circuit breaker disclosed in this specification can prevent unnecessary operation of the earth leakage breaker due to the noise signal by determining whether or not the noise of the earth leakage signal is included through the discrimination signal generated by following the earth leakage signal to increase the mechanical life of the earth leakage breaker .

The leakage circuit breaker disclosed in this specification determines whether noise is included in the leakage signal through the discrimination signal generated by following the leakage signal and thereby prevents unnecessary operation of the leakage circuit breaker caused by the noise signal, As shown in Fig.

The leakage circuit breaker disclosed in this specification has an effect of performing an appropriate shut-off operation according to the degree of the electric leakage state by performing the shut-off operation in accordance with the determination signal generated by following the electric leakage signal.

It will be apparent to those skilled in the art that various modifications and changes can be made in the present invention without departing from the spirit or scope of the present invention as defined by the appended claims. And such modifications and the like should be considered to fall within the scope of the following claims.

10: Trip coil 20: Detector
21: Video Current Transformer (ZCT) 22: Amplifier
30: Signal generator 31: Charge / discharge circuit
32: first voltage discriminator 33: second voltage discriminator
34: Pulse generator 35: Switch
40: Control unit 50: Earth leakage breaker

Claims (10)

1. An earth leakage breaker for detecting an electric leakage,
A trip coil for disconnecting the line;
A detector for detecting a leakage current signal in the line;
A signal generator for generating a discrimination signal in accordance with the leakage current signal; And
And a control unit for comparing the determination signal with a predetermined reference signal to determine whether the leakage signal is a noise signal and controlling the operation of the trip coil according to the determination result,
The above-
A signal for a short circuit corresponding to a blocking object of the earth leakage breaker or a signal for the noise not corresponding to a blocking object of the earth leakage breaker,
The discrimination signal,
And generating the earth leakage signal according to time,
Wherein,
The size of the earth leakage signal is determined by the period of the discrimination signal and the magnitude of the pulse width, and the operation time of the trip coil is controlled according to the magnitude of the earth leakage signal,
When the magnitude of the leakage signal is larger than the magnitude of the reference signal,
Thereby shortening the operation time of the trip coil. The method according to claim 1,
Wherein:
(ZCT) for detecting the earth leakage signal and an amplifier for amplifying the detected earth leakage signal. The method according to claim 1,
The discrimination signal,
And is generated in the form of a pulse width modulation (PWM) signal. The method of claim 3,
The discrimination signal,
LOW pulse and HIGH pulse. The method according to claim 1,
Wherein the signal generator comprises:
Charge / discharge circuit,
The discrimination signal,
And an output signal of the charge / discharge circuit is generated by following the leakage current signal. 6. The method of claim 5,
Wherein the signal generator comprises:
A first voltage discriminator for comparing the leakage current signal and the output signal with a predetermined first reference voltage to charge the charge / discharge circuit;
A second voltage discriminator for comparing the output signal with the leakage current signal and a predetermined second reference voltage to generate a signal for comparison result;
A pulse generator for generating either the HIGH pulse or the LOW pulse according to the comparison result signal to generate the discrimination signal; And
And a switch connected to the charging and discharging circuit such that the charging and discharging circuit is opened when the HIGH pulse is applied from the pulse generator and the charging and discharging circuit is charged when the LOW pulse is applied Further included,
Wherein the output signal comprises:
And feedback is performed to the second voltage discriminator until the tracking of the leakage signal is completed. The method according to claim 6,
The first reference voltage may be a voltage,
A minimum reference voltage which is a reference for interrupting operation of the earth leakage breaker,
The second reference voltage may be a voltage,
And a minimum reference voltage which is a minimum output reference of the charge / discharge circuit. The method according to claim 6,
Wherein the first voltage discriminator comprises:
When the leakage signal is larger than the first reference voltage,
Discharge circuit so that the output signal becomes equal to the magnitude of the leakage current signal. The method according to claim 6,
Wherein the second voltage discriminator comprises:
When the output signal becomes equal to the leakage current signal,
Generates a rising signal (Vr) that causes the output signal to decrease,
When the output signal becomes equal to the second reference voltage,
And generates a falling signal (Vf) for increasing the output signal. 10. The method of claim 9,
Wherein the pulse generator comprises:
When the rising signal is generated,
Generating the HIGH pulse,
When the falling signal is generated,
And generates the LOW pulse.

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