CN210982716U - Smart electric meter binding post contact failure detection circuitry and device - Google Patents
Smart electric meter binding post contact failure detection circuitry and device Download PDFInfo
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Abstract
The utility model discloses a smart electric meter binding post contact failure detection circuitry and device. The circuit comprises a current sampling circuit, a pre-detection circuit and a signal conditioning circuit, wherein the current sampling circuit is arranged between the wire inlet and outlet connecting terminals of the live wire and the zero line and is respectively connected with the pre-detection circuit and the signal conditioning circuit to collect a live wire current signal and a zero line current signal; the pre-detection circuit is connected with the detection chip and respectively acquires a first high-frequency signal from the zero line current signal and a second high-frequency signal from the live line current signal; the signal conditioning circuit is connected with the detection chip and is used for respectively adjusting the live wire current signal and the zero line current signal to obtain a corresponding first adjusting signal and a corresponding second adjusting signal; the detection chip determines whether a suspected arc exists according to the first high-frequency signal and the second high-frequency signal, and samples the first adjusting signal and the second adjusting signal respectively to judge whether the wiring terminal is in poor contact or not when the suspected arc exists, so that whether the terminal is loosened or not can be found in an early stage, and the detection sensitivity and the safety are improved.
Description
Technical Field
The utility model relates to an electrical detection technical field especially relates to a smart electric meter binding post contact failure detection circuitry and device.
Background
The cable connecting terminal is generally made of metal materials, is limited by factors such as climate change, processing technology, oxidation and the like in the using process, is easy to cause untight pressure connection and insufficient pressure at a connecting part, or causes contact resistance increase due to change of a contact part between contacts, is easy to cause arc discharge and the like, causes local temperature rise when equipment operates, and even causes fire and burnout of the equipment. Daily inspection cannot realize frequent opening of the wire box to detect whether the wiring terminal is loosened, so that loose contact of a cable head becomes a leak of power utilization protection.
At present, the online detection method for looseness of a wiring terminal in the industry mainly utilizes the characteristic that contact resistance between a loosened terminal and a cable is too large to easily cause heating of a contact part, whether the terminal is loosened or not is judged by detecting the temperature of the terminal, the technical realization difficulty and the cost of the mode are lower, but detection elements such as infrared or thermistor and the like need to be arranged under a cable wiring terminal, the processing and assembly process requirements are complex, insulation is strictly guaranteed, if a ceramic insulation shell of the thermistor is damaged by stress, systematic insulation damage can be caused, and electric shock danger is easily caused. Secondly, the temperature measurement mode is realized by setting a terminal over-temperature threshold which is a threshold which can cause the terminal to melt or cause fire, and the threshold represents long-term looseness and heating under large current, and is not easy to be found in the initial stage of the terminal looseness or the condition that the line current is not large, and the sensitivity is not high.
The above is only for the purpose of assisting understanding of the technical solutions of the present invention, and does not represent an admission that the above is the prior art.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a main aim at provides a smart electric meter binding post contact failure detection circuitry and device, aim at solving among the prior art to the not high technical problem of binding post on-line measuring sensitivity and security.
In order to achieve the purpose, the utility model provides a smart electric meter connecting terminal contact failure detection circuit, which comprises a current sampling circuit, a pre-detection circuit, a signal conditioning circuit and a detection chip; wherein,
the current sampling circuit is arranged between the incoming and outgoing line connecting terminals of the live line and between the incoming and outgoing line connecting terminals of the zero line and is respectively connected with the pre-detection circuit and the signal conditioning circuit, and the current sampling circuit is used for collecting a live line current signal and a zero line current signal and sending the live line current signal and the zero line current signal to the pre-detection circuit and the signal conditioning circuit;
the pre-detection circuit is connected with the detection chip and used for receiving the live wire current signal and the zero line current signal, respectively acquiring a first high-frequency signal with the frequency not less than a first preset threshold value from the zero line current signal and acquiring a second high-frequency signal with the frequency not less than the first preset threshold value from the live wire current signal, and sending the first high-frequency signal and the second high-frequency signal to the detection chip;
the signal conditioning circuit is connected with the detection chip and is used for respectively adjusting the live wire current signal and the zero wire current signal to obtain a corresponding first adjusting signal and a second adjusting signal and sending the first adjusting signal and the second adjusting signal to the detection chip;
the detection chip is used for determining whether a suspected arc exists according to the first high-frequency signal and the second high-frequency signal, respectively sampling the first adjusting signal and the second adjusting signal when the suspected arc exists, correspondingly obtaining a first current signal to be detected and a second current signal to be detected, and judging whether the wiring terminal is in poor contact or not according to the current signals to be detected.
Preferably, the current sampling circuit includes a first current sampling unit and a second current sampling unit, the pre-detection circuit includes a first pre-detection unit and a second pre-detection unit, and the signal conditioning circuit includes a first signal conditioning unit and a second signal conditioning unit; wherein,
the first current sampling unit is arranged between an incoming and outgoing wiring terminal of a zero line and is respectively connected with the first pre-detection unit and the first signal conditioning unit;
the first pre-detection unit and the first signal conditioning unit are respectively connected with the detection chip;
the second current sampling unit is arranged between an incoming and outgoing wiring terminal of the live wire and is respectively connected with the second pre-detection unit and the second signal conditioning unit;
the second pre-detection unit and the second signal conditioning unit are respectively connected with the detection chip.
Preferably, the detection chip comprises a first analog-to-digital converter, a first counter, a second analog-to-digital converter, a second counter, an or gate and a microcontroller; wherein,
the first analog-to-digital converter is respectively connected with the first signal conditioning unit, the output end of the OR gate and the microcontroller;
the first counter is respectively connected with the first pre-detection unit and the input end of the OR gate;
the second analog-to-digital converter is respectively connected with the second signal conditioning unit, the output end of the OR gate and the microcontroller;
and the second counter is respectively connected with the second pre-detection unit and the input end of the OR gate.
Preferably, the first current sampling unit comprises a first rogowski coil, and the second current sampling unit comprises a second rogowski coil; the first Rogowski coil penetrates through a zero line, and the second Rogowski coil penetrates through a fire line.
Preferably, the first signal conditioning circuit includes a first auxiliary integrating unit and a first signal amplifying unit, and the second signal conditioning circuit includes a second auxiliary integrating unit and a second signal amplifying unit; wherein,
the first auxiliary integration unit is respectively connected with the first Rogowski coil and the first auxiliary integration unit;
the first signal amplifying unit is respectively connected with the first auxiliary integrating unit and the first analog-to-digital converter;
the second auxiliary integration unit is respectively connected with the second Rogowski coil and the second auxiliary integration unit;
the second signal amplifying unit is respectively connected with the second auxiliary integrating unit and the second analog-to-digital converter.
Preferably, the first current sampling unit is a first sampling resistor, the second current sampling unit is a second sampling resistor, the first sampling resistor is connected with a zero line, and the second sampling resistor is connected with a live wire.
Preferably, the first signal conditioning circuit includes a first boost amplifying unit, and the second signal conditioning circuit includes a second boost amplifying unit; wherein,
the first boost amplifying unit is respectively connected with the first sampling resistor and the first analog-to-digital converter;
the second boost amplifying unit is respectively connected with the second sampling resistor and the second analog-to-digital converter.
Preferably, the first pre-detection unit comprises a first high-pass filter and a first comparator; the first high-pass filter is respectively connected with the first sampling unit, the first signal conditioning unit and the first comparator, and the first comparator is connected with the first counter.
Preferably, the second pre-detection unit comprises a second high-pass filter and a second comparator; the second high-pass filter is respectively connected with the second sampling unit, the second signal conditioning unit and the second comparator, and the second comparator is connected with the second counter.
The utility model also provides a smart electric meter binding post contact failure detection device, smart electric meter binding post contact failure detection device include as above smart electric meter binding post contact failure detection circuitry.
The utility model discloses a smart electric meter binding post contact failure detection circuitry includes current sampling circuit, sets up between the business turn over line binding post of live wire and zero line, and is connected with preliminary examination circuit and signal conditioning circuit respectively, gathers live wire current signal and zero line current signal; the pre-detection circuit is connected with the detection chip and respectively acquires a first high-frequency signal from the zero line current signal and a second high-frequency signal from the live line current signal; the signal conditioning circuit is connected with the detection chip and is used for respectively adjusting the live wire current signal and the zero line current signal to obtain a corresponding first adjusting signal and a corresponding second adjusting signal; the detection chip determines whether a suspected arc exists according to the first high-frequency signal and the second high-frequency signal, and samples the first adjusting signal and the second adjusting signal respectively to judge whether the wiring terminal is in poor contact or not when the suspected arc exists, so that whether the terminal is loosened or not can be found in an early stage, and the detection sensitivity and the safety are improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.
Fig. 1 is a functional block diagram of an embodiment of a contact failure detection circuit of a smart meter terminal of the present invention;
fig. 2 is a schematic view of an application scenario of an embodiment of the contact failure detection circuit of the smart meter terminal of the present invention;
fig. 3 is a schematic structural diagram of an embodiment of a contact failure detection circuit of a terminal of the smart meter according to the present invention;
fig. 4 is the utility model discloses smart electric meter binding post contact failure detection circuitry is applied to smart electric meter's the schematic diagram of arranging.
The reference numbers illustrate:
| reference numerals | Name (R) | Reference numerals | Name (R) |
| 100 | Current sampling circuit | 1 | Live line |
| 200 | |
2 | Live line L outgoing line (service line) |
| 300 | |
3 | Zero line N inlet wire |
| IC | Detection chip | 4 | Zero line N outgoing line (service line) |
| 110 | First |
5 | Live line L (service line) |
| 120 | Second |
6 | Zero line N (service wire) |
| 210 | First |
7 | Relay with a |
| 220 | Second preliminary inspection unit | 8 | Watch case |
The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
It should be noted that, if directional indications (such as upper, lower, left, right, front and rear … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.
In addition, if there is a description relating to "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.
The utility model provides a smart electric meter binding post contact failure detection circuitry.
Referring to fig. 1, in an embodiment, the circuit includes a current sampling circuit 100, a pre-detection circuit 200, a signal conditioning circuit 300 and a detection chip IC, wherein the current sampling circuit 100 is disposed between an incoming and outgoing wiring terminal of a live wire L and between an incoming and outgoing wiring terminal of a zero line N and is respectively connected to the pre-detection circuit 200 and the signal conditioning circuit 300, the current sampling circuit 100 is configured to collect a live wire current signal and a zero line current signal and send the live wire current signal and the zero line current signal to the pre-detection circuit 200 and the signal conditioning circuit 300, the pre-detection circuit 200 is connected to the detection chip IC and is configured to receive the live wire current signal and the zero line current signal and respectively obtain a first high-frequency signal having a frequency not less than a first preset threshold from the live wire current signal and a second high-frequency signal having a frequency not less than a first preset threshold from the zero line current signal and send the first high-frequency signal and the second high-frequency signal to the detection chip IC, the signal conditioning circuit 300 is connected to the live wire current signal and is configured to obtain a second high-frequency signal to adjust the live wire current signal and to the second high-frequency signal and to determine whether the second high-frequency signal and the second high-frequency signal to be detected when the live wire signal and the second high-frequency signal are respectively detected and the arc signal, and the second high-frequency signal to be detected.
It should be noted that, the loosening of the electric meter terminal is roughly divided into two scenarios: one is that the terminal loosens, and the terminal and the cable arc through an air gap; the second is that the contact resistance is too large, especially under the condition of point contact, the contact point is easy to melt under large current to form an air gap, thereby generating arc discharge. The present embodiment uses the presence or absence of a suspected arc in the line as a prerequisite for determining terminal loosening.
It is easy to understand that suspected arcs can be classified into 3 categories, and can occur in 5 locations, namely, an arc (an electricity meter live wire L terminal, an electricity meter zero wire N terminal), an indoor arc (an indoor line, an indoor equipment terminal), and indoor harmonic interference (no arc), wherein, an entrance line from an electricity meter to an indoor is long, although the arc is likely to occur, the material and the arrangement pipeline of the entrance line have strict requirements, the probability of causing the arc is extremely low, and therefore the arc is not considered here.
An effective means of detecting arcing is to use the high frequency part characteristics of the current. Because the electric arc is generated in the line, not necessarily generated on the electric meter connecting terminal, the electric arc can be generated when any point on the subscriber line is loosened and is superposed on the whole loop, and how to distinguish the electric arc is a difficult problem.
The circuit for detecting the looseness of the wiring terminal on line does not need to use a thermistor in the circuit, so that electric shock danger caused by damage of a thermistor shell can be avoided, meanwhile, according to the principle that the farther a fault point is, the more serious the attenuation of high-frequency characteristics of an electric arc is, the fault point is on the wiring terminal of an electric meter, and the high-frequency characteristics of the electric arc are high, the current sampling circuit 100 is arranged on a group of loop starting and stopping terminals (for example, L and N are single-phase electric meters), if the electric arc occurs on a certain terminal, high-frequency signals in a live line current signal and a zero line current signal are completely different, and a detection chip IC judges whether the wiring terminal is in poor contact or not according to the characteristics of the current signals.
Specifically, a pair of current sensors with the same characteristics can be arranged at the electric meter terminal (taking a single-phase electric meter as an example, the live wire L and the zero wire N), whether an electric arc exists on the line is judged through the high-frequency characteristics of the current, then, the high-frequency energy of the electric arc current is divided according to the frequency interval, the live wire L and the zero wire N respectively obtain a group of eigenvectors, and whether the terminal is an electric arc can be identified through further analyzing the eigenvectors, namely, whether a loosening event occurs on the terminal is determined.
In the specific scenario shown in fig. 2, the present embodiment can obtain better effects, that is: the device carrying the circuit is arranged on a general loop of the line, the service line of the device is long, and the possibility of electric arc generation of the service line is extremely low, so that the electric arc is generally generated at an electric meter and in a household room once the electric arc is detected; because of the suppression effect of the line impedance on the high-frequency signal, the present embodiment utilizes the difference in the reaction conditions of the high-frequency characteristics of the current when the arc occurs between the household and the electricity meter as the judgment basis.
The circuit comprises a current sampling circuit, a pre-detection circuit and a signal conditioning circuit, wherein the current sampling circuit is arranged between an incoming line terminal and an outgoing line terminal of a live line and a zero line and is respectively connected with the pre-detection circuit and the signal conditioning circuit to collect a live line current signal and a zero line current signal; the pre-detection circuit is connected with the detection chip and respectively acquires a first high-frequency signal from the zero line current signal and a second high-frequency signal from the live line current signal; the signal conditioning circuit is connected with the detection chip and is used for respectively adjusting the live wire current signal and the zero line current signal to obtain a corresponding first adjusting signal and a corresponding second adjusting signal; the detection chip determines whether a suspected arc exists according to the first high-frequency signal and the second high-frequency signal, and samples the first adjusting signal and the second adjusting signal respectively to judge whether the wiring terminal is in poor contact or not when the suspected arc exists, so that whether the terminal is loosened or not can be found in an early stage, and the detection sensitivity and the safety are improved.
Referring to fig. 1 and 3 together, although some components are not labeled, the connection relationship between the components can be accurately and unambiguously determined from fig. 3.
In this embodiment, the current sampling circuit 100 includes a first current sampling unit 110 and a second current sampling unit 120, the pre-test circuit 200 includes a first pre-test unit 210 and a second pre-test unit 220, the signal conditioning circuit 300 includes a first signal conditioning unit (not labeled) and a second signal conditioning unit (not labeled), wherein the first current sampling unit 110 is disposed between the wire connection terminals of the zero line N and is connected to the first pre-test unit 210 and the first signal conditioning unit, the first pre-test unit 210 and the first signal conditioning unit are connected to the detection chip IC, the second current sampling unit 120 is disposed between the wire connection terminals of the live line L and is connected to the second pre-test unit 220 and the second conditioning unit, and the second pre-test unit 220 and the second signal conditioning unit are connected to the detection chip IC.
In a specific implementation, the first current sampling unit 110 and the second current sampling unit 120 are a pair of current sensors with the same characteristics, the arrangement diagram of the two current sensors in the electric meter can refer to fig. 4, and the live line L (house lead) current sensor 5 and the zero line N (house lead) current sensor are respectively disposed between the live line L incoming line 1 and the live line L outgoing line 2 and between the zero line N incoming line 3 and the zero line N outgoing line 4.
Further, the detection chip IC includes a first analog-to-digital converter (not labeled), a first counter (not labeled), a second analog-to-digital converter (not labeled), a second counter (not labeled), an or gate (not labeled), and a microcontroller (not labeled); the first analog-to-digital converter is respectively connected with the first signal conditioning unit, the output end of the OR gate and the microcontroller; the first counter is respectively connected with the first pre-detection unit 210 and the input end of the or gate; the second analog-to-digital converter is respectively connected with the second signal conditioning unit, the output end of the OR gate and the microcontroller; the second counter is connected to the second pre-inspection unit 220 and the input terminal of the or gate, respectively.
It should be understood that the first counter and the second counter can count the first high frequency pulse number in the first high frequency signal and the second high frequency pulse number in the second high frequency signal respectively within a first preset time; and when the first high-frequency pulse number or the second high-frequency pulse number is larger than a second preset threshold value, judging that the suspected arc exists.
It should be noted that the bandwidth of the current sensor can be selected between 10-20 MHz, preferably 20MHz, to capture more high frequency components of the arc. The sampling rate of the first analog-to-digital converter and the second analog-to-digital converter is at least 2 times of the bandwidth, namely 20-40 MSPS (sampling million times per second). Because the probability of the occurrence of the fault arc is low, the first analog-to-digital converter and the second analog-to-digital converter continuously work in a high-speed state, and both the memory resource and the processor power consumption are very large expenses, therefore, the embodiment designs the pre-detection circuit 200 to judge whether the circuit is suspected to have the arc, and simultaneously, the counter outputs a control signal to the analog-to-digital converter, and the analog-to-digital converter starts sampling to reduce the resource consumption.
It is easy to understand that when at least one of the live current signal or the neutral current signal detects a suspected arc, the first analog-to-digital converter and the second analog-to-digital converter are simultaneously started for sampling.
It should be particularly noted that the present embodiment has a gain effect: after the suspected arc is detected, it is not necessary to further verify whether the arc really occurs (i.e. it is not necessary to distinguish the interference caused by the arc and the indoor impact load, which requires extra hardware and software resource expenditure), but after the suspected arc is located and analyzed by the microcontroller, if the suspected arc is on the electric meter side, it is determined that the arc occurs and is caused by the terminal loosening.
When the rogowski coil is adopted, the first signal conditioning circuit comprises a first auxiliary integrating unit (not marked) and a first signal amplifying unit (not marked), and the second signal conditioning circuit comprises a second auxiliary integrating unit (not marked) and a second signal amplifying unit (not marked); the first auxiliary integration unit is respectively connected with the first Rogowski coil and the first auxiliary integration unit; the first signal amplifying unit is respectively connected with the first auxiliary integrating unit and the first analog-to-digital converter; the second auxiliary integration unit is respectively connected with the second Rogowski coil and the second auxiliary integration unit; the second signal amplifying unit is respectively connected with the second auxiliary integrating unit and the second analog-to-digital converter.
As another embodiment, when a sampling resistor is used, the first signal conditioning circuit includes a first boost amplifying unit (not shown), and the second signal conditioning circuit includes a second boost amplifying unit (not shown); the first boost amplifying unit is respectively connected with the first sampling resistor and the first analog-to-digital converter; the second boost amplifying unit is respectively connected with the second sampling resistor and the second analog-to-digital converter.
Further, the first pre-detection unit 210 includes a first high-pass filter (not shown) and a first comparator (not shown); the first high-pass filter is respectively connected with the first sampling unit, the first signal conditioning unit and the first comparator, and the first comparator is connected with the first counter. The second pre-detection unit 220 comprises a second high-pass filter (not shown) and a second comparator (not shown); the second high-pass filter is respectively connected with the second sampling unit, the second signal conditioning unit and the second comparator, and the second comparator is connected with the second counter.
According to the method, a high-precision time measuring module is not needed, the line positioning is performed by hundreds of meters, and the problems of positioning precision and application cost of the time domain reflection fault arc positioning method applied to an ammeter scene in the prior art are solved.
The utility model also provides a smart electric meter binding post contact failure detection device, the smart electric meter binding post contact failure detection device includes as above-mentioned smart electric meter binding post contact failure detection circuit, the circuit structure of the smart electric meter binding post contact failure detection circuit of the smart electric meter binding post contact failure detection device can refer to the above-mentioned embodiment, and no further description is given here; it can be understood that, because the technical scheme of the above-mentioned smart electric meter binding post contact failure detection circuit is adopted to the smart electric meter binding post contact failure detection device of this embodiment, therefore the smart electric meter binding post contact failure detection device has all the above-mentioned beneficial effects.
The above is only the preferred embodiment of the present invention, and not the scope of the present invention, all the equivalent structures or equivalent flow changes made by the contents of the specification and the drawings or the direct or indirect application in other related technical fields are included in the patent protection scope of the present invention.
Claims (10)
1. A smart electric meter wiring terminal contact failure detection circuit is characterized by comprising a current sampling circuit, a pre-detection circuit, a signal conditioning circuit and a detection chip; wherein,
the current sampling circuit is arranged between the incoming and outgoing line connecting terminals of the live line and between the incoming and outgoing line connecting terminals of the zero line and is respectively connected with the pre-detection circuit and the signal conditioning circuit, and the current sampling circuit is used for collecting a live line current signal and a zero line current signal and sending the live line current signal and the zero line current signal to the pre-detection circuit and the signal conditioning circuit;
the pre-detection circuit is connected with the detection chip and used for receiving the live wire current signal and the zero line current signal, respectively acquiring a first high-frequency signal with the frequency not less than a first preset threshold value from the zero line current signal and acquiring a second high-frequency signal with the frequency not less than the first preset threshold value from the live wire current signal, and sending the first high-frequency signal and the second high-frequency signal to the detection chip;
the signal conditioning circuit is connected with the detection chip and is used for respectively adjusting the live wire current signal and the zero wire current signal to obtain a corresponding first adjusting signal and a second adjusting signal and sending the first adjusting signal and the second adjusting signal to the detection chip;
the detection chip is used for determining whether a suspected arc exists according to the first high-frequency signal and the second high-frequency signal, respectively sampling the first adjusting signal and the second adjusting signal when the suspected arc exists, correspondingly obtaining a first current signal to be detected and a second current signal to be detected, and judging whether the wiring terminal is in poor contact or not according to the current signals to be detected.
2. The contact failure detection circuit of the connection terminal of the smart meter according to claim 1, wherein the current sampling circuit comprises a first current sampling unit and a second current sampling unit, the pre-detection circuit comprises a first pre-detection unit and a second pre-detection unit, and the signal conditioning circuit comprises a first signal conditioning unit and a second signal conditioning unit; wherein,
the first current sampling unit is arranged between an incoming and outgoing wiring terminal of a zero line and is respectively connected with the first pre-detection unit and the first signal conditioning unit;
the first pre-detection unit and the first signal conditioning unit are respectively connected with the detection chip;
the second current sampling unit is arranged between an incoming and outgoing wiring terminal of the live wire and is respectively connected with the second pre-detection unit and the second signal conditioning unit;
the second pre-detection unit and the second signal conditioning unit are respectively connected with the detection chip.
3. The contact failure detection circuit of the connection terminal of the smart meter according to claim 2, wherein the detection chip comprises a first analog-to-digital converter, a first counter, a second analog-to-digital converter, a second counter, an OR gate and a microcontroller; wherein,
the first analog-to-digital converter is respectively connected with the first signal conditioning unit, the output end of the OR gate and the microcontroller;
the first counter is respectively connected with the first pre-detection unit and the input end of the OR gate;
the second analog-to-digital converter is respectively connected with the second signal conditioning unit, the output end of the OR gate and the microcontroller;
and the second counter is respectively connected with the second pre-detection unit and the input end of the OR gate.
4. The smart meter terminal contact failure detection circuit as recited in claim 3, wherein the first current sampling unit comprises a first rogowski coil and the second current sampling unit comprises a second rogowski coil; the first Rogowski coil penetrates through a zero line, and the second Rogowski coil penetrates through a fire line.
5. The contact failure detection circuit of the connection terminal of the smart meter according to claim 4, wherein the first signal conditioning circuit comprises a first auxiliary integrating unit and a first signal amplifying unit, and the second signal conditioning circuit comprises a second auxiliary integrating unit and a second signal amplifying unit; wherein,
the first auxiliary integration unit is respectively connected with the first Rogowski coil and the first auxiliary integration unit;
the first signal amplifying unit is respectively connected with the first auxiliary integrating unit and the first analog-to-digital converter;
the second auxiliary integration unit is respectively connected with the second Rogowski coil and the second auxiliary integration unit;
the second signal amplifying unit is respectively connected with the second auxiliary integrating unit and the second analog-to-digital converter.
6. The contact failure detection circuit of the connection terminal of the smart meter according to claim 3, wherein the first current sampling unit is a first sampling resistor, the second current sampling unit is a second sampling resistor, the first sampling resistor is connected with a zero line, and the second sampling resistor is connected with a live line.
7. The contact failure detection circuit of the connection terminal of the smart meter according to claim 6, wherein the first signal conditioning circuit comprises a first boost amplifying unit, and the second signal conditioning circuit comprises a second boost amplifying unit; wherein,
the first boost amplifying unit is respectively connected with the first sampling resistor and the first analog-to-digital converter;
the second boost amplifying unit is respectively connected with the second sampling resistor and the second analog-to-digital converter.
8. The contact failure detection circuit of the connection terminal of the smart meter according to any one of claims 3 to 7, wherein the first pre-detection unit comprises a first high-pass filter and a first comparator; the first high-pass filter is respectively connected with the first current sampling unit, the first signal conditioning unit and the first comparator, and the first comparator is connected with the first counter.
9. The contact failure detection circuit of the connection terminal of the intelligent electric meter according to claim 8, wherein the second pre-detection unit comprises a second high-pass filter and a second comparator; the second high-pass filter is respectively connected with the second current sampling unit, the second signal conditioning unit and the second comparator, and the second comparator is connected with the second counter.
10. A smart meter terminal contact failure detection device, comprising the smart meter terminal contact failure detection circuit according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921701516.3U CN210982716U (en) | 2019-10-11 | 2019-10-11 | Smart electric meter binding post contact failure detection circuitry and device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921701516.3U CN210982716U (en) | 2019-10-11 | 2019-10-11 | Smart electric meter binding post contact failure detection circuitry and device |
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| CN210982716U true CN210982716U (en) | 2020-07-10 |
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| CN201921701516.3U Active CN210982716U (en) | 2019-10-11 | 2019-10-11 | Smart electric meter binding post contact failure detection circuitry and device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110632550A (en) * | 2019-10-11 | 2019-12-31 | 威胜集团有限公司 | Method, circuit and device for detecting poor contact of terminals of smart electric meter |
| CN112180135A (en) * | 2020-10-26 | 2021-01-05 | 杭州海兴电力科技股份有限公司 | Zero line interference preventing electric energy meter adjusting method and electric energy meter |
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2019
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110632550A (en) * | 2019-10-11 | 2019-12-31 | 威胜集团有限公司 | Method, circuit and device for detecting poor contact of terminals of smart electric meter |
| CN110632550B (en) * | 2019-10-11 | 2025-02-14 | 威胜集团有限公司 | Method, circuit and device for detecting poor contact of smart meter terminal blocks |
| CN112180135A (en) * | 2020-10-26 | 2021-01-05 | 杭州海兴电力科技股份有限公司 | Zero line interference preventing electric energy meter adjusting method and electric energy meter |
| CN112180135B (en) * | 2020-10-26 | 2023-11-07 | 杭州海兴电力科技股份有限公司 | An electric energy meter adjustment method to prevent zero line interference and the electric energy meter thereof |
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