CN216870659U - Intelligent ammeter capable of preventing electricity stealing and electricity stealing prevention system - Google Patents
Intelligent ammeter capable of preventing electricity stealing and electricity stealing prevention system Download PDFInfo
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- CN216870659U CN216870659U CN202122998064.3U CN202122998064U CN216870659U CN 216870659 U CN216870659 U CN 216870659U CN 202122998064 U CN202122998064 U CN 202122998064U CN 216870659 U CN216870659 U CN 216870659U
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Abstract
The utility model relates to an electricity stealing prevention intelligent ammeter and an electricity stealing prevention system, wherein the intelligent ammeter comprises an electric quantity metering unit U, a relay K1, a processor and a voltage signal sampling circuit, wherein the electric quantity metering unit U is provided with a live wire input end and a live wire output end; relay K1 has the first end that links to each other with electric quantity measurement unit U's live wire output and is used for connecting the second end of external load's live wire input, electric quantity measurement unit U is connected to the treater, electric quantity measurement unit U's live wire output is connected to this voltage signal sampling circuit's first signal sampling end, this smart electric meter's zero line input is connected to voltage signal sampling circuit's second signal sampling end, voltage signal sampling circuit connection treater, thereby two voltage signal that detect after relay disconnection in smart electric meter through this voltage signal sampling circuit and the judgement between the corresponding threshold value, with judge whether the bypass electricity stealing has taken place, thereby realize accurate the detection to the bypass electricity stealing behavior.
Description
Technical Field
The utility model relates to the field of electricity stealing prevention, in particular to an intelligent ammeter and an electricity stealing prevention system for preventing electricity stealing.
Background
Currently, smart meters are widely used in the field of electric power. However, during the normal operation of the power system, there still exists the occurrence of electricity stealing behavior against the power grid, which seriously interferes with the normal operation of the power grid, and brings great loss to economic development.
Currently, the main electricity stealing behavior for the power grid is bypass electricity stealing. Referring to fig. 1, for load management reasons, the power management part usually makes the relay K1 in the electric energy meter in an open (i.e. open) state, so that the rear-end electrical appliance cannot work normally, thereby achieving the effect of opening and limiting the power. However, if an illegal person short-circuits the terminal P1 and the terminal P2 on the live wire of the electric energy meter with a conductive wire, the electric appliance at the rear end can still be normally powered and continue to work, and the electric energy meter cannot measure the energy consumption of the electric appliance generated by the electricity stealing behavior, so that the normal electricity utilization order is seriously disturbed, and the normal management and monitoring of the power supply of the power grid are not facilitated.
SUMMERY OF THE UTILITY MODEL
The first technical problem to be solved by the present invention is to provide an electricity stealing prevention smart meter for accurately detecting the bypass electricity stealing behavior in view of the above prior art.
The second technical problem to be solved by the utility model is to provide an electricity stealing prevention system applying the intelligent ammeter for preventing electricity stealing.
The third technical problem to be solved by the utility model is to provide another electricity stealing prevention system applying the intelligent ammeter for preventing electricity stealing.
The technical scheme adopted by the utility model for solving the first technical problem is as follows: anti-electricity-theft smart electric meter includes:
the electric quantity metering unit U is provided with a live wire input end and a live wire output end;
the relay K1 is provided with a first end connected with the live wire output end of the electric quantity metering unit U and a second end connected with the live wire input end of an external load;
the processor is connected with the electric quantity metering unit U;
the intelligent electric meter is characterized by further comprising a voltage signal sampling circuit, wherein a first signal sampling end of the voltage signal sampling circuit is connected with a live wire output end of the electric quantity metering unit U, a second signal sampling end of the voltage signal sampling circuit is connected with a zero line input end of the intelligent electric meter, and the voltage signal sampling circuit is connected with the processor.
As a first implementation manner of the voltage signal sampling circuit, in this utility model, the voltage signal sampling circuit includes:
a first end of the first voltage dividing resistor R1 is connected with a live wire output end of the electric quantity metering unit U;
a first end of the second voltage-dividing resistor R2 is connected with a second end of the first voltage-dividing resistor R1, and a second end of the second voltage-dividing resistor R2 is connected with a zero line input end of the intelligent electric meter;
and the anode of the capacitor C1 is connected with the first end of the second voltage-dividing resistor R2, and the cathode of the capacitor C1 is connected with the second end and connected with the zero line input end of the intelligent electric meter.
In this embodiment, the voltage signal sampling circuit includes:
a first end of the first voltage dividing resistor R1 is connected with a live wire output end of the electric quantity metering unit U;
a first end of the second voltage-dividing resistor R2 is connected with a second end of the first voltage-dividing resistor R1, and a second end of the second voltage-dividing resistor R2 is connected with a zero line input end of the intelligent electric meter;
the positive electrode of the capacitor C1 is connected with the first end of the second voltage-dividing resistor R2, and the negative electrode of the capacitor C1 is connected with the second end and connected with the zero line input end of the intelligent electric meter;
and a transistor Q having a base connected to the positive electrode of the capacitor C1, a collector connected to the voltage Vcc, and an emitter connected to the ground.
The technical scheme adopted by the utility model for solving the second technical problem is as follows: the electricity stealing prevention system is characterized in that the intelligent ammeter for preventing electricity stealing is applied.
In this utility model, the anti-electricity-theft system further includes:
the live wire L is connected with the live wire input end of the electric quantity metering unit U;
the zero line N is connected with the zero line input end of the intelligent ammeter;
and the load M is provided with a live wire input end and a zero wire input end, the live wire input end of the load M is connected with the second end of the relay K1, and the zero wire input end of the load M is connected with the zero wire output end of the intelligent electric meter.
In order to facilitate the monitoring of the far-end to the electricity stealing behavior event, the utility model provides an improved electricity stealing prevention system still includes the monitor terminal who is located the far-end, and this monitor terminal connects smart electric meter.
The technical scheme adopted by the utility model for solving the third technical problem is as follows: the electricity stealing prevention system is characterized in that the intelligent ammeter for preventing electricity stealing is applied.
In this utility model, the anti-electricity-theft system further includes:
the live wire L is connected with the live wire input end of the electric quantity metering unit U;
the zero line N is connected with the zero line input end of the intelligent ammeter;
and the load M is provided with a live wire input end and a zero wire input end, the live wire input end of the load M is connected with the second end of the relay K1, and the zero wire input end of the load M is connected with the zero wire output end of the intelligent electric meter.
In order to facilitate the monitoring of the far-end to the electricity stealing behavior event, the utility model provides an improved electricity stealing prevention system still includes the monitor terminal who is located the far-end, and this monitor terminal connects smart electric meter.
Compared with the prior art, the utility model has the advantages that: the utility model discloses a set up voltage signal sampling circuit through increasing in smart electric meter, and make this voltage signal sampling circuit's a signal sampling end connect smart electric meter inner electricity metering unit U's live wire output, this smart electric meter's zero line input is connected to this voltage signal sampling circuit's another signal sampling end, thereby two voltage signal that detect after the relay switching-off in smart electric meter through this voltage signal sampling circuit and the judgement between the corresponding threshold value, with the bypass electricity stealing that has judged whether has taken place, thereby realize accurate the detection to the bypass electricity stealing action.
Drawings
FIG. 1 is a schematic circuit diagram illustrating a bypass electricity stealing situation in an existing power grid;
FIG. 2 is a schematic diagram of an electricity stealing prevention smart meter according to an embodiment of the utility model;
fig. 3 is a schematic diagram of an electricity stealing prevention system according to a first embodiment of the utility model;
FIG. 4 is a schematic flow chart illustrating an electricity stealing prevention detection method according to a first embodiment of the present invention;
FIG. 5 is a schematic diagram of an electricity stealing prevention system in a second embodiment of the utility model;
fig. 6 is a schematic flow chart of an electricity larceny prevention detection method in the second embodiment of the present invention.
Detailed Description
The utility model is described in further detail below with reference to the accompanying examples.
Example one
As shown in fig. 2, the present embodiment provides an electricity stealing prevention smart meter. Specifically, the electricity larceny prevention smart meter of the embodiment includes an electricity metering unit U, a relay K1, a processor (not shown in the figure) and a voltage signal sampling circuit, wherein the electricity metering unit U has a live wire input end and a live wire output end; the relay K1 is provided with a first end connected with the live wire output end of the electric quantity metering unit U and a second end connected with the live wire input end of an external load; the processor is connected with the electric quantity metering unit U; the first signal sampling end of the voltage signal sampling circuit is connected with the live wire output end of the electric quantity metering unit U, the second signal sampling end of the voltage signal sampling circuit is connected with the zero line input end of the intelligent electric meter, and the voltage signal sampling circuit is connected with the processor. Wherein, this smart electric meter's live wire input is connected to electric quantity metering unit U's live wire input, and this smart electric meter's live wire output is connected to relay K1's second end.
Specifically, the voltage signal sampling circuit of this embodiment includes a first voltage-dividing resistor R1, a second voltage-dividing resistor R2, and a capacitor C1, where a first end of the first voltage-dividing resistor R1 is connected to the live line output end of the electricity metering unit U, a first end of the second voltage-dividing resistor R2 is connected to a second end of the first voltage-dividing resistor R1, and a second end of the second voltage-dividing resistor R2 is connected to the neutral line input end of the smart meter; the positive electrode of the capacitor C1 is connected with the first end of the second voltage-dividing resistor R2, and the negative electrode of the capacitor C1 is connected with the second end and connected with the zero line input end of the intelligent electric meter. The terminal point P3 represents a neutral line input end of the intelligent electric meter, the terminal point P4 represents a neutral line output end of the intelligent electric meter, and VCC represents a voltage end. It should be noted that, the first voltage dividing resistor R1 and the second voltage dividing resistor R2 are used for resistance voltage division, the commercial power voltage signal is reduced by a certain proportion and then filtered, and is input to the AD for sampling, and finally, a voltage effective value is output, and then whether a voltage signal exists between the live wire output end of the electric quantity metering unit U and the zero line input end of the smart meter is judged according to the voltage effective value. The voltage signal sampling circuit of the embodiment can determine the value of the voltage signal, and is less affected by the amplitude and the frequency of the mains voltage.
The smart meter of the embodiment is connected to a power grid to form an electricity larceny prevention system. Specifically, referring to fig. 3, the electricity larceny prevention system of this embodiment includes not only the above-mentioned intelligent electric meter for preventing electricity larceny, but also includes a live wire L, a null wire N and an electricity-consuming load M of the commercial power, where the live wire L is connected to the live wire input end of the electricity metering unit U, the null wire N is connected to the null wire input end of the intelligent electric meter, the load M has a live wire input end and a null wire input end, the live wire input end of the load M is connected to the second end of the relay K1, and the null wire input end of the load M is connected to the null wire output end of the intelligent electric meter.
In order to facilitate the remote monitoring of the electricity stealing behavior event, the electricity stealing prevention system of the embodiment further comprises a monitoring terminal located at the remote end, and the monitoring terminal is connected with the intelligent electric meter. For example, the monitoring terminal is connected with the intelligent electric meter in a wireless mode.
The following describes a situation of a method for detecting fraudulent use of electricity in a fraudulent use prevention system in this embodiment with reference to fig. 4. The electricity larceny prevention detection method of the electricity larceny prevention system comprises the following steps:
step S1, detecting the switching-off state of a relay K1 in the intelligent electric meter;
step S2, a judgment process is made according to the detection result for the relay K1:
when the relay K1 is in the switching-off state, judging that bypass electricity stealing does not occur, and switching to the step S1 to continuously detect the switching-off state of the relay K1 in the intelligent electric meter; otherwise, go to step S3;
step S3, detecting the voltage of the live wire output end of the electric quantity metering unit U;
step S4, determining according to the detected voltage at the live wire output terminal:
when the effective voltage value of the live wire output end is larger than a preset voltage threshold value, judging that bypass electricity stealing occurs, and executing a countermeasure aiming at the occurrence of an electricity stealing event, for example, triggering the report of the electricity stealing event; otherwise, it indicates that bypass electricity stealing does not occur currently, and the process goes to step S3 to continue detecting the voltage at the live wire output end of the electricity metering unit U.
In order to perform tracing processing on the starting time and the ending time of the electricity stealing event under the condition of accurately detecting the electricity stealing event, as an improvement, the electricity stealing prevention detection method of the electricity stealing system in the embodiment further comprises the following steps:
step S41, counting the duration that the effective voltage value of the live wire output end is greater than a preset voltage threshold;
step S42, making judgment processing according to the counted duration:
when the duration is greater than the preset duration threshold, for example, the preset duration threshold is set to 3 seconds, it is determined that the bypass electricity stealing behavior is occurring, and the process goes to step S43; otherwise, go to step S41;
step S43, obtaining the counted starting time and ending time of the duration, and using the starting time as the starting time of the bypass electricity stealing event and the ending time as the ending time of the bypass electricity stealing event.
Example two
As shown in fig. 5, the second embodiment provides another smart meter for preventing electricity theft. Specifically, the electricity larceny prevention smart meter of the embodiment includes an electricity metering unit U, a relay K1, a processor (not shown in the figure) and a voltage signal sampling circuit, wherein the electricity metering unit U has a live wire input end and a live wire output end; the relay K1 is provided with a first end connected with the live wire output end of the electric quantity metering unit U and a second end connected with the live wire input end of an external load; the processor is connected with the electric quantity metering unit U; the first signal sampling end of the voltage signal sampling circuit is connected with the live wire output end of the electric quantity metering unit U, the second signal sampling end of the voltage signal sampling circuit is connected with the zero line input end of the intelligent electric meter, and the voltage signal sampling circuit is connected with the processor. Wherein, this smart electric meter's live wire input is connected to electric quantity metering unit U's live wire input, and this smart electric meter's live wire output is connected to relay K1's second end.
Specifically, the voltage signal sampling circuit of this embodiment includes a first voltage-dividing resistor R1, a second voltage-dividing resistor R2, a capacitor C1, and a transistor Q, where a first end of the first voltage-dividing resistor R1 is connected to a live wire output end of the electricity metering unit U; the first end of the second voltage-dividing resistor R2 is connected with the second end of the first voltage-dividing resistor R1, and the second end of the second voltage-dividing resistor R2 is connected with the zero line input end of the intelligent electric meter; the positive electrode of the capacitor C1 is connected with the first end of the second voltage-dividing resistor R2, and the negative electrode of the capacitor C1 is connected with the second end and connected with the zero line input end of the intelligent electric meter; the base of the triode Q is connected with the anode of the capacitor C1, the collector of the triode Q is connected with the voltage Vcc, and the emitter of the triode Q is connected with the ground terminal. It should be noted that, the first voltage dividing resistor R1 and the second voltage dividing resistor R2 are used for resistance voltage division, the commercial power voltage signal is reduced by a certain proportion and then filtered, and is input to the triode Q, and finally, a square wave signal is output, and whether a voltage signal exists between the live wire output end of the electric quantity metering unit U and the zero line input end of the smart meter is judged according to the square wave signal. The voltage signal sampling circuit of the embodiment only needs a common IO port, and has low requirement on hardware.
The intelligent electric meter of the second embodiment is connected to a power grid to form an electricity larceny prevention system. Specifically, referring to fig. 5, the electricity larceny prevention system of this embodiment includes not only the above-mentioned intelligent electric meter for preventing electricity larceny, but also includes a live wire L, a null wire N and an electricity-consuming load M of the commercial power, where the live wire L is connected to the live wire input end of the electricity metering unit U, the null wire N is connected to the null wire input end of the intelligent electric meter, the load M has a live wire input end and a null wire input end, the live wire input end of the load M is connected to the second end of the relay K1, and the null wire input end of the load M is connected to the null wire output end of the intelligent electric meter.
In order to facilitate the remote monitoring of the electricity stealing behavior event, the electricity stealing prevention system of the embodiment further comprises a monitoring terminal located at the remote end, and the monitoring terminal is connected with the intelligent electric meter. For example, the monitoring terminal is connected with the intelligent electric meter in a wireless mode.
The following describes a situation of a method for detecting fraudulent use of electricity in a fraudulent use prevention system in this embodiment with reference to fig. 4. The electricity larceny prevention detection method of the electricity larceny prevention system comprises the following steps:
step a1, detecting the switching-off state of a relay K1 in the intelligent electric meter;
step a2, according to the detection result of relay K1, judging:
when the relay K1 is in the switching-off state, judging that bypass electricity stealing does not occur, and switching to a step a1 to continuously detect the switching-off state of the relay K1 in the intelligent electric meter; otherwise, go to step a 3;
a3, detecting the pulse width of the voltage waveform output by the live wire output end of the electric quantity metering unit U;
step a4, making judgment according to the detected pulse width of the voltage waveform output by the live wire output end:
when the pulse width of the voltage waveform output by the live wire output end is larger than a preset pulse width threshold value, judging that bypass electricity stealing occurs, and executing a countermeasure aiming at the bypass electricity stealing event, for example, triggering the report of the electricity stealing event; otherwise, it indicates that bypass electricity stealing does not occur currently, and the process goes to step a3 to continue to detect the pulse width of the voltage waveform output by the live wire output end of the electricity metering unit U.
In order to perform tracing processing on the starting time and the ending time of the electricity stealing event under the condition of accurately detecting the electricity stealing event, as an improvement, the electricity stealing prevention detection method of the electricity stealing system in the embodiment further comprises the following steps:
step a41, counting the duration of the voltage waveform output by the live wire output end with the pulse width greater than a preset pulse width threshold;
step a42, making judgment according to the counted duration:
when the duration is greater than the preset duration threshold, for example, the preset duration threshold is set to 3 seconds, it is determined that the bypass electricity stealing behavior is occurring, and the step a43 is performed; otherwise, go to step a 41;
step a43, obtaining the start time and the end time of the duration of the statistics, and taking the start time as the start time of the bypass electricity stealing event, and taking the end time as the end time of the bypass electricity stealing event.
Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that modifications and variations of the present invention are possible to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. Anti-electricity-theft's smart electric meter includes:
the electric quantity metering unit U is provided with a live wire input end and a live wire output end;
the relay K1 is provided with a first end connected with the live wire output end of the electric quantity metering unit U and a second end connected with the live wire input end of an external load;
the processor is connected with the electric quantity metering unit U;
the intelligent electric meter is characterized by further comprising a voltage signal sampling circuit, wherein a first signal sampling end of the voltage signal sampling circuit is connected with a live wire output end of the electric quantity metering unit U, a second signal sampling end of the voltage signal sampling circuit is connected with a zero line input end of the intelligent electric meter, and the voltage signal sampling circuit is connected with the processor.
2. The electricity stealing prevention smart meter of claim 1, wherein the voltage signal sampling circuit comprises:
a first end of the first voltage dividing resistor R1 is connected with a live wire output end of the electric quantity metering unit U;
a first end of the second voltage-dividing resistor R2 is connected with a second end of the first voltage-dividing resistor R1, and a second end of the second voltage-dividing resistor R2 is connected with a zero line input end of the intelligent electric meter;
and the anode of the capacitor C1 is connected with the first end of the second voltage-dividing resistor R2, and the cathode of the capacitor C1 is connected with the second end and connected with the zero line input end of the intelligent electric meter.
3. The electricity stealing prevention smart meter of claim 1, wherein the voltage signal sampling circuit comprises:
a first end of the first voltage dividing resistor R1 is connected with a live wire output end of the electric quantity metering unit U;
a first end of the second voltage-dividing resistor R2 is connected with a second end of the first voltage-dividing resistor R1, and a second end of the second voltage-dividing resistor R2 is connected with a zero line input end of the intelligent electric meter;
the positive electrode of the capacitor C1 is connected with the first end of the second voltage-dividing resistor R2, and the negative electrode of the capacitor C1 is connected with the second end and connected with the zero line input end of the intelligent electric meter;
and a transistor Q having a base connected to the positive electrode of the capacitor C1, a collector connected to the voltage Vcc, and an emitter connected to the ground.
4. Electricity stealing prevention system, characterized in that a smart meter for preventing electricity stealing according to claim 2 is applied.
5. An anti-electricity-theft system according to claim 4, further comprising:
the live wire L is connected with the live wire input end of the electric quantity metering unit U;
the zero line N is connected with a zero line input end of the intelligent ammeter;
and the load M is provided with a live wire input end and a zero wire input end, the live wire input end of the load M is connected with the second end of the relay K1, and the zero wire input end of the load M is connected with the zero wire output end of the intelligent electric meter.
6. An anti-electricity-theft system according to claim 4 or 5, further comprising a monitoring terminal at a remote location, the monitoring terminal being connected to the smart meter.
7. Electricity stealing prevention system, characterized in that a smart meter for preventing electricity stealing according to claim 3 is applied.
8. An anti-theft system according to claim 7, further comprising:
the live wire L is connected with the live wire input end of the electric quantity metering unit U;
the zero line N is connected with a zero line input end of the intelligent ammeter;
and the load M is provided with a live wire input end and a zero wire input end, the live wire input end of the load M is connected with the second end of the relay K1, and the zero wire input end of the load M is connected with the zero wire output end of the intelligent electric meter.
9. An anti-electricity-theft system according to claim 7 or 8, further comprising a monitoring terminal at a remote location, the monitoring terminal being connected to the smart meter.
10. The system for avoiding electric larceny as claimed in claim 9, wherein the monitoring terminal is connected with the smart meter in a wireless manner.
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| CN114217125A (en) * | 2021-11-30 | 2022-03-22 | 宁波三星智能电气有限公司 | Intelligent ammeter capable of preventing electricity theft, electricity theft prevention system and electricity theft prevention detection method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114217125A (en) * | 2021-11-30 | 2022-03-22 | 宁波三星智能电气有限公司 | Intelligent ammeter capable of preventing electricity theft, electricity theft prevention system and electricity theft prevention detection method thereof |
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