CN103430036A - Earth leakage detection device - Google Patents

Abstract

Provided is an earth leakage detection device capable of quickly distinguishing between an ordinary earth leakage and a thunder surge. The earth leakage detection device comprises: a zero-phase current transformer (ZCT) (10) through which AC cable runs pass; an integration calculation unit (20) for integrating the output voltage of the zero-phase current transformer (10); an integrated value comparison unit (30) for, when the calculation result obtained by the integration calculation unit (20) is greater than a predetermined range, outputting a first signal; a waveform identification unit (40) for detecting and counting the inflection points of the output voltage waveform of the zero-phase current transformer and for, when the number of the inflection points reaches a predetermined number, outputting a second signal; and an earth current detection unit (50) for, when the integrated value comparison unit (30) outputs the first signal and the waveform identification unit (40) outputs the second signal, outputting an earth leakage detection signal indicating that earth leakage is occurring in the AC cable runs.

Description

Leakage detection device

technical field

The invention relates to a leakage detection device. In particular, it relates to a leakage detection device for judging whether leakage occurs in an AC circuit according to the detection output of a zero-phase current transformer.

Background technique

The leakage interruption device has a zero-phase current transformer (ZCT) composed of an annular iron core (core) and a toroidal (toroidal) coil wound on the core, wherein the iron core is made of a soft magnetic material, etc. The magnetic body is formed, and a plurality of primary conductors constituting an AC circuit pass through the iron core, and the leakage cut-off device determines whether there is a fault in the plurality of primary conductors based on the detection output at both ends of the coil of the zero-phase current transformer, that is, the output voltage. Leakage.

When leakage occurs in a certain primary conductor, a difference occurs between the current flowing in the outward direction and the current flowing in the return direction of the AC circuit, and a leakage current based on the difference occurs. Furthermore, since the passing currents of the plurality of primary conductors are unbalanced as a whole, the state of the magnetic flux of the core of the zero-phase converter changes due to the magnetic flux generated by the leakage current. Thus, an induced voltage corresponding to the leakage current is detected at both ends of the coil of the zero-phase current transformer.

In addition, when no leakage occurs in any of the primary conductors, it is in a so-called balanced state, that is, the vector sum of the energized currents of the plurality of primary conductors is zero. In this balanced state, although there is magnetic flux at the core of the zero-phase converter, these magnetic fluxes cancel each other out, and the induced voltage as mentioned above will not be detected through the zero-phase converter. Therefore, by outputting the output voltage at both ends of the coil of the zero-phase current transformer as a detection output, it is possible to determine whether or not a leakage current has occurred in the AC circuit.

As a case where a leakage of a leakage current is detected, a state of a normal leakage and a state of a lightning surge are considered. The normal leakage refers to a leakage in which the current value of the leakage current periodically appears. The lightning surge refers to a leakage current in which the current value of the leakage current is relatively large and the current value temporarily appears.

In the case of an ordinary leakage among the two types of leakage, it is expected that the leakage will occur for a long time, so it is preferable to cut off the power supply through the AC circuit as soon as possible. On the other hand, in the case of a lightning surge, the electric leakage occurs only temporarily, so it is not preferable to cut off the power supply through the AC circuit every time a lightning surge occurs.

As a conventional earth leakage breaker, an earth leakage breaker capable of preventing unnecessary disconnection due to a lightning surge is known (for example, refer to Patent Document 1). The leakage circuit breaker uses the second comparator with a larger threshold than the first comparator that detects the leakage current to prevent the damage caused by lightning surge or severe grounding (especially the leakage current with a relatively large leakage current among common leakage currents). The ground current and the leakage current are distinguished. And, during the period of the time gate (time gate) made by the monostable multivibrator activated according to the output of the second comparator, it is detected by the 3-wave counter whether or not more than 3 waves are output from the first comparator. pulse, so as to distinguish lightning surge from severe grounding. As a result, the cutoff signal is output from the cutoff signal output circuit only in the case of normal earth leakage including severe grounding.

Patent Document 1: Japanese Unexamined Patent Application Publication No. H10-094161

However, in the earth leakage breaker disclosed in Patent Document 1, in order to distinguish a lightning surge from a normal earth leakage, depending on the situation, it is necessary to count three times the leakage current with a relatively large current value. That is, in an AC circuit, a leakage current is generated along with the waveform of the AC power supply, and a pulse is generated when the leakage current on the positive side or the negative side exceeds a predetermined value, and the leakage current is judged by counting such pulses three times in a row. In the method of determining the leakage current by counting the leakage current three times in this way, it takes a long time to detect the leakage current. In the case of normal leakage, especially serious grounding, a relatively large leakage current may continue to flow. Therefore, from the viewpoint of human body protection, it is preferable to determine whether it is normal leakage or lightning surge as quickly as possible.

However, the leakage interrupter disclosed in Patent Document 1 performs leakage interruption, but does not perform leakage display using effective values or the like based on the output voltage of the zero-phase converter. Therefore, it is impossible for a manager or the like to recognize to what extent electric leakage has occurred. In addition, if an earth-leakage interruption and an earth-leakage display are to be performed at the same time, it is desirable to achieve cost reduction by making the structure as simple as possible.

The present invention has been made in view of the above circumstances, and provides a leakage detection device capable of identifying common leakage and lightning surge as quickly as possible.

The present invention has been made in view of the above circumstances, and provides an electric leakage detection device capable of performing both leakage interruption and leakage display with a simple and inexpensive structure.

Contents of the invention

An electric leakage detection device based on one embodiment of the present invention includes: a zero-phase current transformer through which an AC circuit passes; an integral calculation unit that integrates the output voltage of the above-mentioned zero-phase current transformer; and compares the integral value. A section that outputs a first signal when the calculation result of the integral operation section is greater than a predetermined range; a waveform discrimination section that detects and counts inflection points of the output voltage waveform of the zero-phase converter, and when the number of inflection points reaches outputting a second signal in the case of a predetermined number; and an electric leakage detection unit that outputs a signal indicating that the AC circuit occurs when the first signal is output from the integral value comparison unit and the second signal is output from the waveform determination unit. Leakage detection signal of leakage.

It is desirable that the waveform discrimination unit starts detection of the inflection point when the output voltage of the zero-phase converter is a positive voltage or a negative voltage.

Moreover, it is desirable that the said integral calculation part obtains the effective value of the output voltage of the said zero-phase current transformer using integral calculation.

In addition, the said integral calculation part may calculate|require the average value of the output voltage of the said zero-phase current transformer using integral calculation.

The waveform discrimination unit may include: a pulse generation unit that generates pulses based on the output voltage waveform of the zero-phase converter; and a pulse counting unit that counts the number of pulses generated by the pulse generation unit. When the number of pulses reaches a predetermined number, the above-mentioned second signal is output.

It is preferable that the said pulse generation part generate|occur|produces the said pulse when the output voltage of the said zero-phase converter exceeds a predetermined range.

Moreover, the said pulse generation part may generate|occur|produce the said pulse, when the state in which the output voltage of the said zero-phase converter exceeds a predetermined range continues for predetermined time or more.

Moreover, it is preferable that the said pulse generation part stops generation|occurrence|production of the said pulse, when the output voltage of the said zero-phase converter becomes lower than predetermined voltage after starting to generate|occur|produce the said pulse.

In addition, the pulse generation unit may be configured to stop generation of the pulse when a predetermined time has elapsed since generation of the pulse was started.

In addition, the pulse generation unit may be configured to stop generation of the second pulse before a predetermined time elapses from generation of the first pulse.

Preferably, the pulse counting unit counts the number of rising edges of the pulses generated by the pulse generating unit, and outputs the second signal when the number reaches a predetermined number.

The pulse counting unit may be configured to count when the pulse width of the pulse generated by the pulse generating unit is equal to or greater than a predetermined width, and to output the second signal when the number of pulses reaches a predetermined number.

In addition, the pulse counting unit may be configured to count the number of falling edges of the pulses generated by the pulse generating unit, and output the second signal when the number reaches a predetermined number.

In addition, the pulse counting unit may stop counting the second pulse before a predetermined time elapses from counting the first pulse generated by the pulse generating unit.

The waveform discrimination unit may include a count value change unit for counting the count value counted by the pulse count unit when the pulse output width based on the pulse generated by the pulse generation unit is equal to or greater than a predetermined width. Make changes.

Desirably, the above pulse output width is a time width from an output start time point to an output end time point of the pulse generated by the pulse generation unit.

The pulse output width may be a duration from the output start time of the first pulse generated by the pulse generator to the output start time of the second pulse following the first pulse.

In addition, the pulse output width may be a duration from the output end time of the first pulse generated by the pulse generating unit to the output end time of the second pulse following the first pulse.

In addition, the pulse output width may be a time width from the output start time of the first pulse generated by the pulse generating unit to the end time of the second pulse output.

In addition, the leakage detection device may further include a pulse generation condition changing unit for changing the pulse generation condition of the pulse generation unit based on the count value counted by the pulse count unit.

Preferably, the pulse generating condition changing unit changes at least one of a voltage threshold used for determining whether the pulse generating unit generates a pulse, and a pulse width threshold used for determining whether the pulse generating unit generates a pulse. Whether to use when counting pulses.

In addition, the above-mentioned pulse generator may also generate a positive-side pulse and a negative-side pulse, the positive-side pulse is a pulse based on the positive-side output voltage of the above-mentioned zero-phase converter, and the negative-side pulse is based on the output voltage of the above-mentioned zero-phase converter. pulses of the output voltage on the negative side, the pulse counting unit counts the positive side pulses and the negative side pulses, and when at least one of the number of the positive side pulses and the number of the negative side pulses is a predetermined number or more Next, the above-mentioned second signal is output.

In addition, the leakage detection device may further include a signal input unit for inputting a signal output instruction signal for causing the integral value comparison unit to output the first signal or the waveform discrimination unit to output the second signal.

Preferably, the signal input unit inputs the signal output instruction signal from an external resistor.

In addition, the leakage detection device may further include: an integrating unit that integrates the output voltage of the above-mentioned zero-phase current transformer; The result output unit and the electric leakage detection unit may be constituted by one module.

It is desirable that the leakage detection unit uses the integration unit as the integration calculation unit.

In addition, the integration unit may be configured to average the output voltages of the zero-phase current transformers over a longer period than the integration calculation unit to calculate an average value, and to integrate the average value.

Preferably, the calculation result output unit outputs a warning signal when the calculation result of the integration unit is larger than a predetermined range narrower than a range of a lower voltage threshold that is determined by the integration value comparison unit when it is determined whether to output the warning signal. above the first signal is used.

In addition, the calculation result output unit may be configured to change an output method when outputting the warning signal based on the calculation result of the integration unit.

The leakage detection device may further include a calculation result storage unit that stores information on the calculation result of the integrating unit for a predetermined period of time.

In addition, it is desirable that the leakage detection device further includes an external terminal unit for outputting information on the calculation result stored in the calculation result storage unit.

In addition, an information output unit that outputs information on the calculation result stored in the calculation result storage unit to a storage medium may be further provided.

In addition, it may further include an information transmission unit that transmits the information of the calculation result stored in the calculation result storage unit to an external server.

The leakage detection device according to other embodiments of the present invention includes: a zero-phase current transformer through which an AC circuit passes; a first integral calculation unit that integrates the output voltage of the above-mentioned zero-phase current transformer; A unit that outputs a leakage detection signal indicating that leakage has occurred in the AC circuit based on the calculation result of the first integral calculation unit; a second integral calculation unit that integrates the output voltage of the zero-phase current transformer; and calculation The result output unit performs an output corresponding to the calculation result of the second integral calculation unit, wherein the calculation result output unit and the leakage detection unit are constituted by one module.

Preferably, the electric leakage detection unit uses the second integral calculation unit as the first integral calculation unit.

In addition, the second integral calculation unit may be configured to average the output voltages of the zero-phase current transformers over a longer period than the first integral calculation unit to calculate an average value, and to calculate the average value. integral.

It is desirable to include an integral value comparison unit that outputs a first signal when the calculation result of the first integral calculation unit exceeds a predetermined range, and the calculation result output unit is connected to the second integral calculation unit. A warning signal is output when the calculation result is larger than a predetermined range narrower than a range of a lower voltage threshold used for determining whether to output the first signal by the integral value comparison unit.

In addition, the calculation result output unit may be configured to change an output method when outputting the warning signal based on the calculation result of the second integral calculation unit.

The leakage detection device may further include a calculation result storage unit that stores information on the calculation result of the second integral calculation unit for a predetermined period of time.

In addition, it is desirable that the leakage detection device further includes an external terminal unit for outputting information on the calculation result stored in the calculation result storage unit.

In addition, an information output unit that outputs information on the calculation result stored in the calculation result storage unit to a storage medium may be further provided.

In addition, it may be configured to further include an information transmission unit that transmits the information of the calculation result stored in the calculation result storage unit to an external server.

In addition, an integral value comparison unit that outputs a first signal when the calculation result of the first integral calculation unit exceeds a predetermined range; and a waveform discrimination unit that detects the output of the zero-phase current transformer The inflection points of the voltage waveform are counted, and the second signal is output when the number of the inflection points reaches a predetermined number. In the case of two signals, the above-mentioned electric leakage detection signal is output.

It is desirable that the waveform discrimination unit starts detection of the inflection point when the output voltage of the zero-phase converter is a positive voltage or a negative voltage.

Moreover, it is desirable that the said 1st integral calculation part obtains the effective value of the output voltage of the said zero-phase current transformer using integral calculation.

In addition, the said 1st integral calculation part may calculate|require the average value of the output voltage of the said zero-phase current transformer using integral calculation.

The waveform discrimination unit may include: a pulse generation unit that generates pulses based on the output voltage waveform of the zero-phase converter; and a pulse counting unit that counts the number of pulses generated by the pulse generation unit. When the number of pulses reaches a predetermined number, the above-mentioned second signal is output.

It is preferable that the said pulse generation part generate|occur|produces the said pulse when the output voltage of the said zero-phase converter exceeds a predetermined range.

Moreover, the said pulse generation part may generate|occur|produce the said pulse, when the state in which the output voltage of the said zero-phase converter exceeds a predetermined range continues for predetermined time or more.

Moreover, it is preferable that the said pulse generation part stops generation|occurrence|production of the said pulse, when the output voltage of the said zero-phase converter becomes lower than predetermined voltage after starting to generate|occur|produce the said pulse.

In addition, the pulse generation unit may be configured to stop generation of the pulse when a predetermined time has elapsed since generation of the pulse was started.

In addition, the pulse generation unit may be configured to stop generation of the second pulse before a predetermined time elapses from generation of the first pulse.

Preferably, the pulse counting unit counts the number of rising edges of the pulses generated by the pulse generating unit, and outputs the second signal when the number reaches a predetermined number.

The pulse counting unit may be configured to count when the pulse width of the pulse generated by the pulse generating unit is equal to or greater than a predetermined width, and to output the second signal when the number of pulses reaches a predetermined number.

In addition, the pulse counting unit may be configured to count the number of falling edges of the pulses generated by the pulse generating unit, and output the second signal when the number reaches a predetermined number.

In addition, the pulse counting unit may stop counting the second pulse before a predetermined time elapses from counting the first pulse generated by the pulse generating unit.

The waveform discrimination unit may include a count value change unit for counting the count value counted by the pulse count unit when the pulse output width based on the pulse generated by the pulse generation unit is equal to or greater than a predetermined width. Make changes.

Desirably, the above pulse output width is a time width from an output start time point to an output end time point of the pulse generated by the pulse generation unit.

The pulse output width may be a duration from the output start time of the first pulse generated by the pulse generator to the output start time of the second pulse following the first pulse.

In addition, the pulse output width may be a duration from the output end time of the first pulse generated by the pulse generating unit to the output end time of the second pulse following the first pulse.

In addition, the pulse output width may be a time width from the output start time of the first pulse generated by the pulse generating unit to the end time of the second pulse output.

In addition, the leakage detection device may further include a pulse generation condition changing unit for changing the pulse generation condition of the pulse generation unit based on the count value counted by the pulse count unit.

Preferably, the pulse generating condition changing unit changes at least one of a voltage threshold used for determining whether the pulse generating unit generates a pulse, and a pulse width threshold used for determining whether the pulse generating unit generates a pulse. Whether to use when counting pulses.

In addition, the above-mentioned pulse generator may also generate a positive-side pulse and a negative-side pulse, the positive-side pulse is a pulse based on the positive-side output voltage of the above-mentioned zero-phase converter, and the negative-side pulse is based on the output voltage of the above-mentioned zero-phase converter. pulses of the output voltage on the negative side, the pulse counting unit counts the positive side pulses and the negative side pulses, and when at least one of the number of the positive side pulses and the number of the negative side pulses is a predetermined number or more Next, the above-mentioned second signal is output.

In addition, the leakage detection device may further include a signal input unit for inputting a signal output instruction signal for causing the integral value comparison unit to output the first signal or the waveform discrimination unit to output the second signal.

Preferably, the signal input unit inputs the signal output instruction signal from an external resistor.

The effect of the invention

According to the present invention, ordinary electric leakage and lightning surge can be identified as quickly as possible.

Description of drawings

The purpose and features of the present invention will be clarified by the following drawings and description of preferred embodiments.

FIG. 1 is a circuit block diagram showing a configuration example of an electric leakage detection device in the first embodiment of the present invention.

2 is a circuit block diagram showing a detailed configuration example of a waveform discrimination unit in the first embodiment of the present invention.

Fig. 3 is a timing chart for explaining a first example of operation of the leakage detection device in the first embodiment of the present invention.

FIG. 4 is a timing chart for illustrating a second operation example of the leakage detection device in the first embodiment of the present invention.

FIG. 5 is a time chart illustrating a third operation example of the leakage detection device in the first embodiment of the present invention.

6 is a time chart for explaining a fourth operation example of the leakage detection device in the first embodiment of the present invention.

7 is a time chart for explaining a fifth operation example of the leakage detection device in the first embodiment of the present invention.

8 is a circuit block diagram showing a detailed configuration example of a waveform discrimination unit in a second embodiment of the present invention.

FIG. 9 is a time chart illustrating an example of operation of the leakage detection device in the second embodiment of the present invention.

10 is a circuit block diagram showing a detailed configuration example of a waveform discrimination unit in a third embodiment of the present invention.

FIG. 11 is a timing chart for explaining an example of operation of the leakage detection device in the third embodiment of the present invention.

12 is a circuit block diagram showing a detailed configuration example of a waveform discrimination unit in a fourth embodiment of the present invention.

FIG. 13 is a timing chart for explaining an example of operation of the leakage detection device in the fourth embodiment of the present invention.

14 is a circuit block diagram showing a configuration example of an electric leakage detection device in a fifth embodiment of the present invention.

15 is a block diagram showing a first configuration example of an electric leakage detection device in a sixth embodiment of the present invention.

FIG. 16 is a block diagram showing a second configuration example of the leakage detection device in the sixth embodiment of the present invention.

Fig. 17 is a block diagram showing a third configuration example of the leakage detection device in the sixth embodiment of the present invention.

FIG. 18 is a block diagram showing a fourth configuration example of the leakage detection device in the sixth embodiment of the present invention.

FIG. 19 is a block diagram showing a fifth configuration example of the leakage detection device in the sixth embodiment of the present invention.

20 is a block diagram showing a sixth configuration example of an electric leakage detection device in a sixth embodiment of the present invention.

Detailed ways

Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings constituting a part of this specification. In all the drawings, the same or similar parts are attached with the same reference numerals and descriptions thereof are omitted.

(first embodiment)

FIG. 1 is a block diagram showing a configuration example of an electric leakage detection device in the first embodiment of the present invention. Leakage detection device 100 shown in FIG. 1 is configured to include zero-phase current transformer 10 , integral calculation unit 20 , integral value comparison unit 30 , waveform discrimination unit 40 , and leakage detection unit 50 .

The zero-phase converter 10 is composed of an annular iron core (core) and a toroidal coil wound on the core, wherein the iron core is formed of a magnetic body such as a soft magnetic material, and constitutes a three-phase circuit. A plurality of primary conductors of an alternating current circuit passing through the iron core. When a difference occurs between the current flowing in the outward direction and the current flowing in the homeward direction of the AC circuit, a leakage current based on the difference is generated in the zero-phase converter 10 . Furthermore, an induced voltage corresponding to the leakage current is generated at both ends of the coil. The zero-phase converter 10 outputs the induced voltage to the integral operation unit 20 and the waveform determination unit 40 as the output voltage of the zero-phase converter 10 , that is, the ZCT output voltage. In addition, although not shown in figure, in order to obtain the voltage output from the zero-phase current transformer 10, the resistance element is inserted in parallel with the zero-phase current transformer 10.

The integral computing unit 20 is constituted by an integrating circuit or the like, integrates the ZCT output voltage, and outputs the integrated voltage (integrated voltage) as an output voltage to the integral value comparing unit 30 .

In addition, the integral calculation unit 20 may use integral calculation to obtain the effective value of the ZCT output voltage. For example, the square value of the ZCT output voltage is integrated for one cycle and divided by the time of one cycle to obtain the square root of the value. In this case, the leakage current can be detected with higher accuracy, thereby improving the leakage detection performance against the distorted wave. In addition, the integral calculation unit 20 may use integral calculation to obtain the average value of the ZCT output voltage. For example, the absolute value of the ZCT output voltage is integrated for one cycle and divided by the time of one cycle to calculate the absolute value average. This absolute value average is used for comparison in the integral value comparison unit 30 . In this case, the calculation amount can be reduced compared with the case of obtaining an effective value, and the leakage detection device 100 can be configured at low cost.

The integral value comparator 30 is composed of a comparator circuit, etc., and outputs a voltage H to the electric leakage detection portion 50 when the absolute value of the integral value obtained by the integral operation portion 20, that is, the absolute value is equal to or greater than an integral value judgment threshold value th1 as a predetermined value (see image 3). Here, the integral value determination threshold th1 is a positive number. On the other hand, when the absolute value of the integrated value is smaller than the integrated value determination threshold th1 , the voltage L is output to the leakage detection unit 50 . The case where the output voltage of the integral value comparison unit 30 is the voltage H corresponds to the case where the integral value comparison unit 30 outputs a predetermined signal (first signal). In addition, the voltage H is higher than the voltage L.

The waveform determination unit 40 detects and counts inflection points of the voltage waveform of the ZCT output voltage, and outputs a voltage H to the electric leakage detection unit 50 when the number of inflection points reaches a predetermined number. On the other hand, when the number of inflection points has not reached the predetermined number, the voltage L is output to the leakage detection unit 50 . The case where the output voltage of the waveform discriminating unit 40 is the voltage H corresponds to the case where the waveform discriminating unit 40 outputs a predetermined signal (second signal). Here, the predetermined number is, for example, "2", "3" and the like. In addition, the detailed structure of the waveform determination part 40 is mentioned later.

In addition, the waveform determination unit 40 may start the detection of the above-mentioned inflection point when the ZCT output voltage is a positive voltage, or may start the detection of the above-mentioned inflection point when the ZCT output voltage is a negative voltage. Thereby, the inflection point can be detected at high speed, and the AC circuit can be disconnected at a higher speed in the case of a normal leakage.

Leakage detection unit 50 is constituted by an AND circuit, and outputs voltage H when the output voltage of integral value comparison unit 30 is voltage H and the output voltage of waveform discrimination unit 40 is voltage H. The case where the output voltage of the leakage detection unit 50 is the voltage H corresponds to the case where a leakage detection signal indicating that a leakage has occurred in the AC circuit is output. In addition, the leakage detection signal is sent to a trip coil (not shown) that disconnects the circuit contact of the AC circuit as a disconnection signal (for disconnecting the AC circuit) for disconnecting the circuit contact. As a result, the circuit contacts of the AC circuit are opened.

Next, a detailed configuration of the waveform discrimination unit 40 will be described. FIG. 2 is a block diagram showing a detailed configuration example of the waveform discrimination unit 40 . The waveform discriminating unit 40 shown in FIG. 2 is configured to include a pulse generating unit 41 and a pulse counting unit 42 .

The pulse generating unit 41 is composed of a pulse generating circuit and the like, and generates pulses based on the ZCT output voltage. In the example of FIG. 3 , a short-term voltage of a predetermined voltage value (voltage H) is output as a pulse.

The pulse counting unit 42 is composed of a pulse counter or the like, and counts the number of pulses generated by the pulse generating unit 41 , and when the number of pulses reaches a predetermined number, sets the output voltage to voltage H to output the above-mentioned second signal. On the other hand, when the number of pulses has not reached the predetermined number, the output voltage is set to the voltage L, and the above-mentioned second signal is not output.

Next, the operation of the leakage detection device 100 of this embodiment will be described. FIG. 3 is a time chart illustrating a first example of operation of the leakage detection device 100 according to the present embodiment.

In the example of FIG. 3 , it is assumed that the pulse generator 41 generates a narrow pulse when the absolute value of the ZCT output voltage is equal to or greater than the leakage current detection threshold th2. Here, the leakage current detection threshold th2 is a positive number. Such a pulse generating operation of the pulse generating unit 41 corresponds to detecting an inflection point of the output voltage waveform. Accordingly, it is possible to perform operation at a desired leakage current value without malfunction due to lightning surge, and to detect leakage at a higher speed. On the other hand, when the absolute value of the ZCT output voltage is smaller than the leakage current detection threshold th2, no pulse is generated. In addition, here, the count is performed by the pulse counting unit 42 when the pulse rises.

"Leakage current" in FIG. 3 represents the leakage current generated in the zero-phase converter 10 under each case (normal leakage, lightning surge). As shown in FIG. 3 , a periodic leakage current is generated in the case of a normal leakage, and a temporary leakage current with a relatively large current value is generated in the case of a lightning surge.

"ZCT output" in FIG. 3 shows the output voltage (ZCT output voltage) of the zero-phase converter 10 corresponding to the leakage current in each case.

"Pulse generator output" in FIG. 3 shows the output voltage of the pulse generator 41 in each case. In the example of FIG. 3 , three waves of pulses are generated in the case of normal leakage in the same period, while two waves of pulses are generated in the case of lightning surge, and more pulses are generated in the case of normal leakage.

"Counter" in FIG. 3 represents the count value held by the pulse counting unit 42 in each case.

"Counter output" in FIG. 3 shows the output voltage of the pulse counting unit 42 in each case. In the example of FIG. 3 , when the pulse of the third wave is generated, the output voltage of the pulse counting unit 42 becomes the voltage H.

"Integral calculation output" in FIG. 3 shows the output voltage of the integral calculation unit 20 in each case.

"Integral value comparison output" in FIG. 3 shows the output voltage of the integral value comparison unit 30 in each case.

"Leakage detection signal output" in FIG. 3 shows the output voltage of the leakage detection unit 50 in each case.

According to such a 1st operation example, it becomes possible to recognize a normal earth leakage and a lightning surge as quickly as possible.

FIG. 4 is a time chart illustrating a second operation example of the leakage detection device 100 according to the present embodiment.

In the example of FIG. 4 , it is assumed that the pulse generator 41 generates a narrow pulse when the absolute value of the ZCT output voltage is equal to or greater than the leakage current detection threshold th2 for a predetermined time or longer. On the other hand, when the absolute value of the ZCT output voltage is smaller than the leakage current detection threshold th2, or when the state in which the absolute value of the ZCT output voltage is equal to or greater than the leakage current detection threshold th2 has not continued for a predetermined time or longer, no pulse is generated. .

As shown in FIG. 4 , considering the voltage value of the ZCT output voltage and also the continuation of a predetermined time, the “pulse generator output” is output at a timing delayed by a predetermined time compared to FIG. 3 . In the present embodiment, the pulse count unit 42 counts the pulses at the rising edge of the pulses. Accordingly, the timings of "counter", "counter output", and "leakage detection signal output" are also delayed. Accordingly, it is possible to perform operation at a desired leakage current value without malfunction due to lightning surge, and to detect leakage at a higher speed. Moreover, the ability to resist noise is also strong, and the robustness is improved.

In addition, in FIG. 4, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted.

FIG. 5 is a time chart illustrating a third operation example of the leakage detection device 100 .

In the example of FIG. 5 , it is assumed that the pulse generator 41 stops the pulse generation when the absolute value of the ZCT output voltage becomes smaller than the pulse stop determination threshold th3 after the pulse generation starts. On the other hand, when the absolute value of the ZCT output voltage is equal to or greater than the pulse stop determination threshold th3, pulse generation is continued. Here, th2>th3>0.

Therefore, as shown in "Pulse Generator Output" in FIG. 5 , one pulse is generated from when the absolute value of the ZCT output voltage becomes greater than or equal to the leakage current detection threshold th2 until the absolute value becomes smaller than the pulse stop determination threshold th3 . In addition, here, the count is performed by the pulse counting unit 42 when the pulse falls. Therefore, the timings of "counter", "counter output", and "leakage detection signal output" are delayed compared with the case where counting is performed when the pulse rises.

In addition, in FIG. 5, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted.

In addition, here, a case where voltage is considered in order to determine the pulse stop timing point is shown, but time may be considered instead of voltage. For example, the pulse generator 41 may stop the pulse when a predetermined time (predetermined width) t2 has elapsed from the start of pulse generation as shown in FIG. 6 described later. In this way, noise does not affect leakage detection for a predetermined period of time after pulse generation starts.

FIG. 6 is a time chart illustrating a fourth operation example of the leakage detection device 100 according to the present embodiment.

In the example of FIG. 6 , it is assumed that the pulse generating section 41 does not generate the next pulse within a predetermined time after generating a pulse having a predetermined width t2. That is, it is assumed that the pulse generator 41 stops generating the second pulse before a predetermined time elapses from the generation of the first pulse. In the example of FIG. 6 , this pulse output masking period is applied only to normal leakage.

In the example of FIG. 6 , in the normal leakage, one pulse generation timing is included in the pulse output masking period which is a predetermined time. In this case, since the second pulse to be generated by the pulse generator 41 overlaps with the output mask period, the second pulse is generated after the output mask period ends. Therefore, the count value of the pulse count is counted with a delay of one pulse.

In addition, in the example shown by the lightning surge in FIG. 6 , assuming that the first pulse and the second pulse are generated by the pulse generating unit 41 without an output masking period, the pulse counting unit 42 counts the pulses at the falling edge of the pulse, and starts from the second pulse. The counting of the second pulse is stopped before the predetermined time elapses from the counting of one pulse. In the example of FIG. 6, the counting masking period is only applied to the case of lightning surge.

In the example shown by Thunderstorm, the count timing of one pulse is included in the count mask period which is a predetermined time. In this case, since the second pulse to be counted by the pulse counting unit 42 overlaps with the count mask period, the second pulse is counted after the count mask period ends. Therefore, the count value of the pulse count is counted with a delay of one pulse. Therefore, since the timing of the "counter" is delayed, the timings of the "counter output" and "leakage detection signal output" are also delayed accordingly.

In addition, in FIG. 6, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted.

Thus, by providing a pulse mask period or a count mask period of a predetermined time, pulse generation or pulse counting can be accurately performed. In particular, erroneous detection of lightning surge can be prevented, and erroneous operation of leakage detection device 100 can be prevented. In addition, in this embodiment, the generation timing of one pulse is included in the pulse output mask period, and the count timing of one pulse is included in the count mask period. Therefore, when the second pulse is counted, the output of the pulse counting part 42 The voltage becomes voltage H.

FIG. 7 is a time chart illustrating a fifth operation example of the leakage detection device 100 according to the present embodiment.

In the example of FIG. 7 , the pulse generator 41 generates one pulse from when the absolute value of the ZCT output voltage becomes equal to or greater than the leakage current detection threshold th2 until the absolute value becomes smaller than the leakage current detection threshold th2 . In addition, it is assumed that the pulse counting unit 42 counts when the pulse width (time width) of the pulse generated by the pulse generating unit 41 is equal to or greater than a predetermined width A. On the other hand, when the pulse width of the pulse is smaller than the predetermined width A, it is not counted as a pulse.

In addition, here, the count is performed by the pulse counting unit 42 when the pulse falls. Therefore, the timings of "counter", "counter output", and "leakage detection signal output" are delayed compared with the case where counting is performed when the pulse rises.

In addition, in FIG. 7, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted. According to such an operation example, it is possible to easily distinguish and detect a lightning surge from a normal leakage.

(second embodiment)

As shown in FIG. 8 , the leakage detection device 100 of the second embodiment includes a waveform discrimination unit 40B instead of the waveform discrimination unit 40 shown in the first embodiment. In addition, the same code|symbol is attached|subjected to the structure of the leakage detection device 100 of this embodiment which is the same as that of the leakage detection device 100 shown in 1st Embodiment, and description is abbreviate|omitted.

FIG. 8 is a block diagram showing a configuration example of a waveform discrimination unit 40B in the second embodiment of the present invention. The waveform discriminating unit 40B shown in FIG. 8 includes a count value changing unit 43 in addition to the pulse generating unit 41 and the pulse counting unit 42 .

The count value changing unit 43 is composed of a control circuit and the like, detects the pulse output width based on the pulse generated by the pulse generating unit 41, and counts the pulse count unit 42 when the pulse output width is greater than or equal to a predetermined width or less than a predetermined width. The value is changed. For example, it is possible to increase the count value by 1 when the pulse output width is equal to or greater than a predetermined width, and to decrease the count value by 1 when the pulse output width is equal to or less than the predetermined width.

In the present embodiment, the pulse generator 41 generates a pulse in a section where the absolute value of the ZCT output voltage is equal to or greater than the leakage current detection threshold th2. In addition, pulses are counted on the falling edge of each pulse. Here, the "pulse output width" is as follows (see FIG. 9 described later).

(A) Duration A1 from the output start time point (rising time point) of the pulse P1 as the first pulse to the output end time point (falling time point) (threshold value T1 is used in this case)

(B) Duration A2 from the output start time point of the pulse P1 which is the first pulse to the output start time point of the pulse P2 which is the second pulse consecutive to the first pulse (threshold T2 is used in this case)

(C) Time width A3 from the output end time point of the pulse P1 to the output end time point of the pulse P2 (threshold value T3 is used in this case)

(D) Time width A4 from the output start time point of the pulse P1 to the output end time point of the pulse P2 (threshold value T4 is used in this case)

FIG. 9 is a timing chart illustrating an example of the operation of the leakage detection device 100 according to this embodiment.

In the example of FIG. 9 , the counter value is incremented by 1 when the pulse output width A3 is equal to or greater than the threshold value T3 . Thereby, the timing of changing the count value can be flexibly set. Therefore, by setting any one of the time widths A1 to A4 as the pulse output width, the operation time of the leakage detection device 100 is not delayed, and malfunction can be prevented.

In the example shown in FIG. 9, the pulse width A3 between pulses P1 and P2 is greater than the threshold T3 in the case of normal leakage, so at the time point of the falling edge of pulse P2, the count value increases from 1 to 3, at which time A voltage H is generated from the pulse counting unit 42 .

In addition, in FIG. 9, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted.

(third embodiment)

The leakage detection device 100 of the third embodiment includes a waveform discrimination unit 40C instead of the waveform discrimination unit 40 shown in the first embodiment. In addition, the same code|symbol is attached|subjected to the structure of the leakage detection device 100 of this embodiment which is the same as that of the leakage detection device 100 shown in 1st Embodiment, and description is abbreviate|omitted.

FIG. 10 is a block diagram showing a configuration example of a waveform discrimination unit 40C in the third embodiment of the present invention. The waveform discrimination unit 40C shown in FIG. 10 includes a pulse generation condition changing unit 44 in addition to the pulse generation unit 41 and the pulse count unit 42 .

The pulse generating condition changing unit 44 is composed of a control circuit and the like, and changes the pulse generating condition of the pulse generating unit 41 and/or the pulse counting condition of the pulse counting unit 42 based on the count value counted by the pulse counting unit 42 . The pulse generating condition includes a voltage threshold used for determining whether the pulse generating unit 41 generates a pulse, and the pulse counting condition includes a pulse width (time width) threshold and the like. For example, the pulse generation condition changing unit 44 sets at least One party makes changes.

FIG. 11 is a time chart illustrating an example of the operation of the leakage detection device 100 according to this embodiment.

In the example of FIG. 11 , when the pulse widths of the first pulse and the second pulse are longer than A, counting is performed on the falling edge of the pulse, and the pulse generation condition changing unit 44 changes The time threshold value at the time of pulse generation determination by the pulse counting unit 42 is changed. That is, at the time when the count reaches 2, the time threshold value of the pulse generator 41 is changed to instantaneous detection. That is, counting is performed on the rising edge of the pulse. Accordingly, it is possible to prevent malfunction of the electric leakage detection device 100 caused by lightning surge, and to cut off the AC circuit at a higher speed in the case of normal electric leakage.

In addition, in FIG. 11, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted.

(fourth embodiment)

The leakage detection device 100 of the fourth embodiment includes a waveform discrimination unit 40D instead of the waveform discrimination unit 40 shown in the first embodiment. In addition, the same code|symbol is attached|subjected to the structure of the leakage detection device 100 of this embodiment which is the same as that of the leakage detection device 100 shown in 1st Embodiment, and description is abbreviate|omitted.

FIG. 12 is a block diagram showing a configuration example of a waveform discrimination unit 40D in the fourth embodiment of the present invention. The waveform discrimination unit 40D shown in FIG. 12 includes a positive side pulse generation unit 41A, a negative side pulse generation unit 41B, a positive side pulse counting unit 42A, and a negative side pulse counting unit 42B.

The positive-side pulse generator 41A generates a positive-side pulse based on the positive-side ZCT output voltage. Negative side pulse generator 41B generates a negative side pulse based on the negative side ZCT output voltage. In addition, the conditions for generating the positive side pulse or the negative side pulse based on the ZCT output voltage are the same as those described above.

The positive-side pulse count unit 42A counts the positive-side pulses, and when the counted number is equal to or greater than a predetermined number, sets the output voltage to a voltage H and outputs a second signal. Negative side pulse counting unit 42B counts negative side pulses, and when the counted number is equal to or greater than a predetermined number, sets the output voltage to voltage H and outputs a second signal. Therefore, the second signal is output when at least one of the number of positive side pulses and the number of negative side pulses is a predetermined number or more. In addition, the conditions for counting the positive-side pulse or the negative-side pulse are the same as those described above.

FIG. 13 is a time chart illustrating an example of the operation of the leakage detection device 100 according to this embodiment.

"Positive-side pulse generator output" in FIG. 13 shows the output voltage of the positive-side pulse generator 41A in each case. In the example of FIG. 13 , two waves of positive side pulses are generated in the case of normal leakage in the same period, and one wave of positive side pulses is generated in the case of lightning surge, and more pulses are generated in the case of normal leakage.

The "positive side counter" in FIG. 13 shows the count value held by the positive side pulse counting unit 42A in each case.

"Negative side pulse generator output" in FIG. 13 shows the output voltage of the negative side pulse generator 41B in each case. In the example of FIG. 13 , one negative side pulse is generated in the case of a normal leakage in the same period, and one negative side pulse is also generated in the case of a lightning surge.

"Negative side counter" in FIG. 13 shows the count value held by the negative side pulse counting unit 42B in each case.

"Counter output" in FIG. 13 represents the output considering the positive side counter and the negative side counter. In the example of FIG. 13 , when at least one of the positive-side pulse counting unit 42A and the negative-side pulse counting unit 42B counts at least one of the positive-side pulse and the negative-side pulse to two or more waves, the output of the counter output The voltage becomes voltage H. Therefore, in the example of FIG. 13 , the counter output becomes the voltage H only in the case of normal electric leakage. In addition, although not shown, the outputs of the positive side pulse counting unit 42A and the negative side pulse counting unit 42B are output to the leakage output unit 50 through an OR gate.

In addition, in FIG. 13, illustration of "integral calculation output", "integral value comparison output", and "leakage detection signal output" is abbreviate|omitted.

In this manner, pulse generation and pulse counting can be performed by distinguishing the positive side and the negative side of the ZCT output voltage, thereby enabling easy detection of half-wave leakage.

(fifth embodiment)

FIG. 14 is a block diagram showing a configuration example of an electric leakage detection device E in a fifth embodiment of the present invention. Leakage detection device 100E includes zero-phase current transformer 10 , integral calculation unit 20 , integral value comparison unit 30 , waveform discrimination unit 40 , leakage detection unit 50E, and a plurality of logic calculation units that are integrated circuits. Here, although the case where the first logic operation unit 60 and the second logic operation unit 70 are provided as a plurality of logic circuit units has been exemplified, the present invention is not limited thereto. In addition, instead of the waveform discriminating unit 40 , the waveform discriminating units 40B to 40D described above may be used. The components of the leakage detection device 100E according to the present embodiment that are the same as those of the leakage detection device 100 shown in the first to fourth embodiments are denoted by the same symbols, and description thereof will be omitted.

The first logic operation part 60 and the second logic operation part 70 have the function as a signal input part, and the signal input part inputs the signal used to make the output voltage of the integral value comparison part 30 be the voltage H (that is, make it output the first signal). ) and a signal output instruction signal for making the output voltage of the waveform determination unit 40 to be the voltage H (that is, to make it output the second signal). Therefore, the plurality of algorithms described in the first to fourth embodiments can be changed by these circuit units. That is, the first logic operation unit 60 and the second logic operation unit 70 output the first signal and the second signal to the leakage detection unit 50E independently of the outputs of the integral value comparison unit 30 and the waveform determination unit 40 based on signals from the outside. Two signals.

The first logical operation unit 60 is constituted by an OR circuit or the like, and outputs the voltage H when at least one of the output voltage of the integral value comparison unit 30 and the output voltage of the external circuit unit is a voltage H.

The second logical operation unit 70 is constituted by an OR circuit or the like, and outputs the voltage H when at least one of the output voltage of the waveform discrimination unit 40 and the output voltage of the external circuit unit is a voltage H.

In addition, low-capacity chip resistors are considered as the external circuit units of the first logic operation unit 60 and the second logic operation unit 70 . The chip resistors are connected to input pins (pins) of the first logic operation unit 60 and the second logic operation unit 70 . Accordingly, a circuit including an external circuit unit can be configured at low cost. It is also possible to output an indication signal from an external resistance input signal in this way.

Leakage detection unit 50E is constituted by an AND circuit, and outputs voltage H when the output voltage of first logic operation unit 60 is voltage H and the output voltage of second logic operation unit 70 is voltage H. The case where the output voltage of the leakage detection unit 50E is the voltage H corresponds to the case where a leakage detection signal indicating that a leakage has occurred in the AC circuit is output. In addition, the leakage detection signal is sent to a trip coil (not shown) that disconnects the circuit contact of the AC circuit as a disconnection signal (for disconnecting the AC circuit) for disconnecting the circuit contact. As a result, the circuit contacts of the AC circuit are opened.

According to the electric leakage detection device 100E of this embodiment, if the output voltage of the external circuit unit connected to the first logical operation unit 60 is set to the voltage H, then the integrated value comparison unit of the first to fourth embodiments The case where the output voltage of 30 is always the voltage H is equivalent, so the function of the integral value comparison unit 30 can be disabled. Similarly, if the output voltage of the external circuit unit connected to the second logical operation unit 70 is the voltage H, then the waveform discrimination unit 40 and the like (of 40 , 40B to 40D) in the first to fourth embodiments will be The case where the output voltage of any one) is always the voltage H is equivalent, so the functions of the waveform determination unit 40 and the like can be disabled. That is, it is possible to disable one function using the external circuit unit.

In addition, although the case where some functions of the leakage detection device 100E are disabled using the first logical operation unit 60 and the second logical operation unit 70 has been described, these circuit units may not be used. For example, it may also be configured such that thresholds such as voltage thresholds and time thresholds for changing at least one of the integral computing unit 20, the integral value comparing unit 30, and the waveform judging unit 40 are input from an external device not shown, or used for changing A change signal of the count value. For example, when each threshold is changed, the measured voltage and measurement time may always be changed to values exceeding the threshold. Also, for example, the count value may be changed to a value that always exceeds the count threshold. According to such a configuration, it is also possible to disable some functions of the electric leakage detection device 100E in the same manner.

(sixth embodiment)

FIG. 15 is a block diagram showing a configuration example of an electric leakage detection device 100F in a sixth embodiment of the present invention. The leakage detection device 100F of the present embodiment includes a zero-phase current transformer 10 , a first system (leakage level detection unit 80 ), and a second system having the division-by-zero phase described in the first to fifth embodiments. The second system integrates the output voltage (ZCT output voltage) of the zero-phase converter 10 and outputs according to the integration result. That is, the first system implements a function related to leakage cutoff, and the second system implements a function for notifying the user of the leakage amount (leakage current value).

The electric leakage level detection unit 80 as the first system includes the integral calculation unit 20 , the integral value comparison unit 30 , the waveform discrimination unit 40 , the electric leakage detection unit 50 and the like as described above. Among them, the leakage level detection unit 80 includes at least the integral calculation unit 20 and the leakage detection unit 50 . When the leakage level detection unit 80 includes only the integral calculation unit 20 and the leakage detection unit 50 , the leakage detection unit 50 outputs a leakage detection signal based on the calculation result of the integration calculation unit 20 .

The second system includes an integrating unit 91 and a calculation result output unit 92 . The integrating unit 91 integrates the ZCT output voltage, and has the same configuration as the integrating unit 20 described above. The calculation result output unit 92 performs an output corresponding to the calculation result (integrated value) of the integrating unit 91 . The calculation result output unit 92 outputs various information through, for example, a display not shown, a speaker, and the like. Here, as the calculation result, for example, the effective value (effective value calculation result) of the ZCT output voltage obtained by the integral calculation and the average value (average value calculation result) of the ZCT output voltage obtained by the integral calculation as described above are output.

Here, the components of the first system and the second system are configured in one integrated circuit (one module). Therefore, by configuring the leakage detection device 100F in the same package in this way, cost reduction can be achieved. That is, leakage interruption and leakage display can be performed simultaneously with a simple and inexpensive structure.

In addition, as shown in FIG. 16 , the integration unit 91 may be used as the integration calculation unit 20 described in the first embodiment. That is, the leakage level detection unit 80 may not be provided with the integration calculation unit 20 , and the output of the integration unit 91 may be input from the integration value comparison unit 30 . In this way, cost reduction can be achieved by sharing the structure for performing integration. In addition, since the hardware such as the integral circuit is shared, it will not be affected by the difference in hardware and the calculation method used for the integral calculation, so there will be no difference between the level detection value used for leakage detection and the display value used to display the degree of leakage. An error occurs, so adjustments can be made in such a way that no contradiction occurs between the two.

In addition, the calculation result output unit 92 may output a value (average value) obtained by averaging the integrated values calculated by the integrating unit 91 . In addition, the integral value comparison unit 30 may compare a value (average value) obtained by averaging the integral values calculated by the integral calculation unit 20 with a predetermined value (integral value determination threshold th1). The average value means, for example, a time average. At this time, it is preferable that the period when the calculation result output unit 92 averages is longer than the period when the integral value comparison unit 30 performs the average. In addition, the integrating unit 91 may average the ZCT output voltages over a longer period than the integrating unit 20 to calculate the average value of the ZCT output voltage, and integrate the average value to obtain an integral value. Thereby, the integrated value (corresponding to the leakage current value) and the like can be accurately output without being affected by fluctuations in the ZCT output voltage due to noise such as a surge voltage.

In addition, although the average value has been described here, an effective value may be used instead of the average value.

In addition, the calculation result output unit 92 may output a warning signal (alarm) when the absolute value of the calculation result (integrated value) of the integrating unit 91 is greater than the threshold value th4, which is higher than the threshold value th4 in the leakage level detection unit 80. The leakage current detection threshold th2 for leakage detection is small (th2>th4>0). Regarding the warning signal here, a warning using sound information, a warning using display information, and the like can be considered. That is, the warning signal may be output when the calculation result of the integrating unit 91 is greater than the threshold value th2 used for determining whether to output the first signal by the integrated value comparing unit 30 . Accordingly, the user can recognize the state of the electric leakage before detecting the electric leakage to the extent that the AC circuit is cut off.

In addition, the calculation result output unit 92 may change the output method when outputting the warning signal based on the calculation result of the integrating unit 91 . In this case, for example, it is conceivable to turn on the LED when the absolute value of the calculation result of the integrating unit 91 exceeds 50% of the absolute value of the leakage current detection threshold th2, and to turn on the LED when it exceeds 80% of the absolute value of the leakage current detection threshold th2. In the case of %, an alarm sound is output. Thereby, the urgency (level) from earth leakage cutoff can be notified accurately, and the situation which suddenly causes earth leakage cutoff can be avoided.

In addition, as shown in FIG. 17 , the leakage detection device 100F may include a calculation result storage unit 93 that stores the calculation result of the integrating unit 91 . The calculation result storage unit 93 stores, for example, information on calculation results for a predetermined period of time (one week or the like). In this case, the information may be overwritten after a predetermined time elapses and rewritten. In addition, the information of the calculation result refers to the integrated value (effective value, average value) of the ZCT output voltage, and the like. Thereby, it becomes easy to identify the cause of a disconnection by memorizing the calculation result of the fixed time until earth-leakage disconnection.

In addition, as shown in FIG. 18 , the leakage detection device 100F may include an external terminal unit 94 for outputting information on the calculation result of the integrating unit 91 and information on the calculation result of the calculation result storage unit 93 through an external terminal. . The external terminal unit 94 is, for example, a USB (Universal Serial Bus: Universal Serial Bus) terminal or the like. By providing the external terminal part 94, the information of the calculation result can be output easily, and it becomes easy to identify the cause of disconnection.

In addition, as shown in FIG. 19 , the leakage detection device 100F may include an information output unit 95 that outputs information on the calculation results of the integrating unit 91 and information on the calculation results of the calculation result storage unit 93 to a storage medium. The storage medium is, for example, a USB memory, an SD card, or the like. Thereby, for example, by outputting the calculation result for a fixed period of time until the earth-leakage cutoff to the storage medium, data transfer becomes easy, and it becomes easy to identify the cause of the cutoff.

In addition, as shown in FIG. 20 , the leakage detection device 100F may include an information transmission unit 96 that transmits information on the calculation results of the integrating unit 91 and information on the calculation results of the calculation result storage unit 93 to an external server. Thus, for example, by outputting the calculation result of the fixed time until the leakage cutoff to an external server, the leakage state can be easily grasped by a remote sensor or the like, and the cause of the cutoff can be easily identified.

All the above-mentioned embodiments, the illustrative examples in the embodiments, and the modified examples can be used in combination with each other. Preferred embodiments of the present invention have been described above, but the present invention is not limited to these specific embodiments, and various changes and modifications can be made without departing from the scope of the claims, and these changes and modifications also belong to the scope of the present invention.

Claims (66)

1. A leakage detection device, comprising: A zero-phase converter, the AC circuit runs through the zero-phase converter; an integral operation unit, which integrates the output voltage of the above-mentioned zero-phase converter; an integral value comparison unit that outputs a first signal when the calculation result of the integral calculation unit is greater than a predetermined range; a waveform discrimination unit that detects and counts inflection points of the output voltage waveform of the zero-phase converter, and outputs a second signal when the number of inflection points reaches a predetermined number; and A leakage detection unit that outputs a leakage detection signal indicating that a leakage has occurred in the AC circuit when the first signal is output from the integral comparison unit and the second signal is output from the waveform determination unit. 2. The leakage detection device according to claim 1, characterized in that, The waveform discrimination unit starts detection of the inflection point when the output voltage of the zero-phase converter is a positive voltage or a negative voltage. 3. The leakage detection device according to claim 1 or 2, characterized in that, The said integral operation part obtains the effective value of the output voltage of the said zero-phase current transformer using an integral operation. 4. The leakage detection device according to claim 1 or 2, characterized in that, The said integral calculation part obtains the average value of the output voltage of the said zero-phase current transformer using integral calculation. 5. The leakage detection device according to any one of claims 1 to 4, characterized in that, The above-mentioned waveform discrimination unit has: a pulse generating unit that generates pulses based on the output voltage waveform of the zero-phase converter; and A pulse counting unit counts the number of pulses generated by the pulse generating unit, and outputs the second signal when the number of pulses reaches a predetermined number. 6. The leakage detection device according to claim 5, characterized in that, The said pulse generating part generates the said pulse when the output voltage of the said zero-phase converter exceeds a predetermined range. 7. The leakage detection device according to claim 6, characterized in that, The said pulse generation part generates the said pulse, when the state in which the output voltage of the said zero-phase converter exceeds a predetermined range continues for more than predetermined time. 8. The leakage detection device according to any one of claims 5 to 7, characterized in that, The said pulse generation part stops generation|generation of the said pulse, when the output voltage of the said zero-phase converter becomes lower than predetermined voltage after starting to generate|occur|produce the said pulse. 9. The leakage detection device according to any one of claims 5 to 7, characterized in that, The pulse generation unit stops generation of the pulse when a predetermined time has elapsed since generation of the pulse was started. 10. The leakage detection device according to any one of claims 5 to 9, characterized in that, The pulse generation unit stops generation of the second pulse before a predetermined time elapses from generation of the first pulse. 11. The leakage detection device according to any one of claims 5 to 10, characterized in that, The pulse counting unit counts the number of rising edges of the pulses generated by the pulse generating unit, and outputs the second signal when the number reaches a predetermined number. 12. The leakage detection device according to any one of claims 5 to 10, characterized in that, The pulse counting unit counts when the pulse width of the pulse generated by the pulse generating unit is equal to or greater than a predetermined width, and outputs the second signal when the number of pulses reaches a predetermined number. 13. The leakage detection device according to any one of claims 5 to 10, characterized in that, The pulse counting unit counts the number of falling edges of the pulses generated by the pulse generating unit, and outputs the second signal when the number reaches a predetermined number. 14. The leakage detection device according to any one of claims 5 to 13, characterized in that, The pulse counting unit stops counting the second pulse before a predetermined time elapses from counting the first pulse generated by the pulse generating unit. 15. The leakage detection device according to any one of claims 5 to 14, characterized in that, The waveform discrimination unit includes a count value changing unit that changes the count value counted by the pulse counting unit when a pulse output width based on a pulse generated by the pulse generating unit is equal to or greater than a predetermined width. . 16. The leakage detection device according to claim 15, characterized in that, The pulse output width is a time width from an output start time point to an output end time point of the pulse generated by the pulse generation unit. 17. The leakage detection device according to claim 15, characterized in that, The pulse output width is a time width from an output start time of a first pulse generated by the pulse generator to an output start time of a second pulse following the first pulse. 18. The leakage detection device according to claim 15, characterized in that, The pulse output width is a time width from an output end time of a first pulse generated by the pulse generating unit to an output end time of a second pulse following the first pulse. 19. The leakage detection device according to claim 15, characterized in that, The pulse output width is a time width from the output start time of the first pulse generated by the pulse generating unit to the end time of the second pulse output. 20. The leakage detection device according to any one of claims 5 to 19, characterized in that, A pulse generation condition changing unit is further provided which changes the pulse generation condition of the pulse generation unit based on the count value counted by the pulse count unit. 21. The leakage detection device according to claim 20, characterized in that, The pulse generating condition changing unit changes at least one of a voltage threshold and a pulse width threshold, wherein the voltage threshold is used when determining whether the pulse generating unit generates a pulse, and the pulse width threshold is used when determining whether the pulse is generated. used for counting. 22. The leakage detection device according to any one of claims 5 to 21, characterized in that, The above-mentioned pulse generator generates a positive-side pulse and a negative-side pulse, the positive-side pulse is a pulse based on the output voltage of the positive side of the above-mentioned zero-phase converter, and the negative-side pulse is based on the output voltage of the negative side of the above-mentioned zero-phase converter. output voltage pulses, The pulse counting unit counts the positive side pulses and the negative side pulses, and outputs the second signal when at least one of the number of the positive side pulses and the number of the negative side pulses is a predetermined number or more. 23. The leakage detection device according to any one of claims 5 to 22, characterized in that, A signal input unit for inputting a signal output instruction signal for causing the integral value comparing unit to output the first signal or for causing the waveform determining unit to output the second signal is further provided. 24. The leakage detection device according to claim 23, characterized in that, The signal input unit inputs the signal output instruction signal from an external resistor. 25. The leakage detection device according to any one of claims 1 to 24, further comprising: an integrating unit, which integrates the output voltage of the zero-phase converter; and an operation result output unit that performs an output corresponding to the operation result of the above-mentioned integrating unit, Wherein, the calculation result output unit and the electric leakage detection unit are constituted by one module. 26. The leakage detection device according to claim 25, characterized in that, The leakage detection unit uses the integration unit as the integration calculation unit. 27. The leakage detection device according to claim 25 or 26, characterized in that, The integration unit averages the output voltages of the zero-phase converters over a longer period than the integration calculation unit, calculates an average value, and integrates the average value. 28. The leakage detection device according to any one of claims 25 to 27, characterized in that, The calculation result output unit further outputs a warning signal when the calculation result of the integration unit is larger than a predetermined range narrower than a range of a lower voltage threshold that is determined by the integration value comparison unit to output the first signal is used. 29. The leakage detection device according to claim 28, characterized in that, The calculation result output unit changes an output method when outputting the warning signal based on the calculation result of the integration unit. 30. The leakage detection device according to any one of claims 25 to 29, characterized in that, It also includes a calculation result storage unit that stores information on the calculation results of the integrating unit for a predetermined amount of time. 31. The leakage detection device according to claim 30, characterized in that, An external terminal unit for outputting information on the calculation result stored in the calculation result storage unit is further provided. 32. The leakage detection device according to claim 30, characterized in that, An information output unit that outputs information on the calculation result stored in the calculation result storage unit to a storage medium is further provided. 33. The leakage detection device according to claim 30, characterized in that, It further includes an information transmission unit that transmits information on the calculation result stored in the calculation result storage unit to an external server. 34. A leakage detection device, comprising: A zero-phase converter, the AC circuit runs through the zero-phase converter; a first integral computing unit, which integrates the output voltage of the zero-phase converter; a leakage detection unit that outputs a leakage detection signal indicating that a leakage has occurred in the AC circuit based on the calculation result of the first integral calculation unit; a second integral computing unit, which integrates the output voltage of the zero-phase converter; and a calculation result output unit that outputs an output corresponding to the calculation result of the second integral calculation unit, Wherein, the above-mentioned operation result output unit and the above-mentioned electric leakage detection unit are constituted by one module. 35. The leakage detection device according to claim 34, characterized in that, The leakage detection unit uses the second integral calculation unit as the first integral calculation unit. 36. The leakage detection device according to claim 34 or 35, characterized in that, The second integral calculation unit averages the output voltages of the zero-phase converter over a longer period than the first integral calculation unit, calculates an average value, and integrates the average value. 37. The leakage detection device according to any one of claims 34 to 36, characterized in that, It also includes a calculation result storage unit that stores information on the calculation results of the second integral calculation unit for a predetermined period of time. 38. The leakage detection device according to claim 37, characterized in that, An external terminal unit for outputting information on the calculation result stored in the calculation result storage unit is further provided. 39. The leakage detection device according to claim 37, characterized in that, An information output unit that outputs information on the calculation result stored in the calculation result storage unit to a storage medium is further provided. 40. The leakage detection device according to claim 37, characterized in that, It further includes an information transmission unit that transmits information on the calculation result stored in the calculation result storage unit to an external server. 41. The leakage detection device according to any one of claims 34 to 36, characterized in that, further comprising an integral value comparison unit that outputs a first signal when the calculation result of the first integral calculation unit is greater than a predetermined range, The calculation result output unit outputs a warning signal when the calculation result of the second integral calculation unit is larger than a predetermined range narrower than a range of a lower voltage threshold that is determined by the integral value comparison unit to output the above-mentioned used for the first signal. 42. The leakage detection device according to claim 41, characterized in that, The calculation result output unit changes an output method when outputting the warning signal based on the calculation result of the second integral calculation unit. 43. The leakage detection device according to any one of claims 34 to 42, further comprising: an integral value comparison unit that outputs a first signal when the calculation result of the first integral calculation unit is greater than a predetermined range; and a waveform discrimination unit that detects and counts inflection points of the output voltage waveform of the zero-phase converter, and outputs a second signal when the number of inflection points reaches a predetermined number, Wherein, the electric leakage detection unit outputs the electric leakage detection signal when the first signal is output by the integral value comparison unit and the second signal is output by the waveform discrimination unit. 44. The leakage detection device according to claim 43, characterized in that, The waveform discrimination unit starts detection of the inflection point when the output voltage of the zero-phase converter is a positive voltage or a negative voltage. 45. The leakage detection device according to claim 43 or 44, characterized in that, The first integral calculation unit obtains an effective value of the output voltage of the zero-phase current transformer by using an integral calculation. 46. The leakage detection device according to claim 43 or 44, characterized in that, The said 1st integral calculation part calculates the average value of the output voltage of the said zero-phase current transformer using integral calculation. 47. The leakage detection device according to any one of claims 43 to 46, characterized in that, The above-mentioned waveform discrimination unit has: a pulse generating unit that generates pulses based on the output voltage waveform of the zero-phase converter; and A pulse counting unit counts the number of pulses generated by the pulse generating unit, and outputs the second signal when the number of pulses reaches a predetermined number. 48. The leakage detection device according to claim 47, characterized in that, The said pulse generating part generates the said pulse when the output voltage of the said zero-phase converter exceeds a predetermined range. 49. The leakage detection device according to claim 48, characterized in that, The said pulse generation part generates the said pulse, when the state in which the output voltage of the said zero-phase converter exceeds a predetermined range continues for more than predetermined time. 50. The leakage detection device according to any one of claims 47 to 49, characterized in that, The said pulse generation part stops generation|generation of the said pulse, when the output voltage of the said zero-phase converter becomes lower than predetermined voltage after starting to generate|occur|produce the said pulse. 51. The leakage detection device according to any one of claims 47 to 49, characterized in that, The pulse generation unit stops generation of the pulse when a predetermined time has elapsed since generation of the pulse was started. 52. The leakage detection device according to any one of claims 47 to 51, characterized in that, The pulse generation unit stops generation of the second pulse before a predetermined time elapses from generation of the first pulse. 53. The leakage detection device according to any one of claims 47 to 52, characterized in that, The pulse counting unit counts the number of rising edges of the pulses generated by the pulse generating unit, and outputs the second signal when the number reaches a predetermined number. 54. The leakage detection device according to any one of claims 47 to 52, characterized in that, The pulse counting unit counts when the pulse width of the pulse generated by the pulse generating unit is equal to or greater than a predetermined width, and outputs the second signal when the number of pulses reaches a predetermined number. 55. The leakage detection device according to any one of claims 47 to 52, characterized in that, The pulse counting unit counts the number of falling edges of the pulses generated by the pulse generating unit, and outputs the second signal when the number reaches a predetermined number. 56. The leakage detection device according to any one of claims 47 to 55, characterized in that, The pulse counting unit stops counting the second pulse before a predetermined time elapses from counting the first pulse generated by the pulse generating unit. 57. The leakage detection device according to any one of claims 47 to 56, characterized in that, The waveform discrimination unit includes a count value changing unit that changes the count value counted by the pulse counting unit when a pulse output width based on a pulse generated by the pulse generating unit is equal to or greater than a predetermined width. . 58. The leakage detection device according to claim 57, characterized in that, The pulse output width is a time width from an output start time point to an output end time point of the pulse generated by the pulse generation unit. 59. The leakage detection device according to claim 57, characterized in that, The pulse output width is a time width from an output start time of a first pulse generated by the pulse generator to an output start time of a second pulse following the first pulse. 60. The leakage detection device according to claim 57, characterized in that, The pulse output width is a time width from an output end time of a first pulse generated by the pulse generating unit to an output end time of a second pulse following the first pulse. 61. The leakage detection device according to claim 57, characterized in that, The pulse output width is a time width from the output start time of the first pulse generated by the pulse generating unit to the end time of the second pulse output. 62. The leakage detection device according to any one of claims 47 to 61, characterized in that, A pulse generation condition changing unit is further provided which changes the pulse generation condition of the pulse generation unit based on the count value counted by the pulse count unit. 63. The leakage detection device according to claim 62, characterized in that, The pulse generating condition changing unit changes at least one of a voltage threshold and a pulse width threshold, wherein the voltage threshold is used when determining whether the pulse generating unit generates a pulse, and the pulse width threshold is used when determining whether the pulse is generated. used for counting. 64. The leakage detection device according to any one of claims 47 to 63, characterized in that, The above-mentioned pulse generator generates a positive-side pulse and a negative-side pulse, the positive-side pulse is a pulse based on the output voltage of the positive side of the above-mentioned zero-phase converter, and the negative-side pulse is based on the output voltage of the negative side of the above-mentioned zero-phase converter. output voltage pulses, The pulse counting unit counts the positive side pulses and the negative side pulses, and outputs the second signal when at least one of the number of the positive side pulses and the number of the negative side pulses is a predetermined number or more. 65. The leakage detection device according to any one of claims 47 to 64, characterized in that, A signal input unit for inputting a signal output instruction signal for causing the integral value comparing unit to output the first signal or for causing the waveform determining unit to output the second signal is further provided. 66. The leakage detection device according to claim 65, characterized in that, The signal input unit inputs the signal output instruction signal from an external resistor.

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