CN117452144A - Quick detection device for line faults behind meter - Google Patents
Quick detection device for line faults behind meter Download PDFInfo
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- CN117452144A CN117452144A CN202311598230.8A CN202311598230A CN117452144A CN 117452144 A CN117452144 A CN 117452144A CN 202311598230 A CN202311598230 A CN 202311598230A CN 117452144 A CN117452144 A CN 117452144A
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- 238000001514 detection method Methods 0.000 title claims abstract description 22
- 238000005070 sampling Methods 0.000 claims abstract description 79
- 238000006243 chemical reaction Methods 0.000 claims abstract description 6
- 238000000034 method Methods 0.000 claims description 10
- 238000001914 filtration Methods 0.000 claims description 4
- 238000007781 pre-processing Methods 0.000 claims description 4
- 230000010354 integration Effects 0.000 claims description 3
- 230000000737 periodic effect Effects 0.000 claims description 3
- 230000008439 repair process Effects 0.000 description 5
- 238000011835 investigation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
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- 238000010586 diagram Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/088—Aspects of digital computing
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- Measurement Of Current Or Voltage (AREA)
Abstract
The invention provides a fast detection device for line faults after a meter, which comprises the following components: the sampling module is used for respectively sampling alternating voltage signals at a front section line switch of the electric meter and a rear section line switch of the electric meter by utilizing an alternating voltage amplitude detection algorithm to obtain a front voltage signal of the electric meter and a rear voltage signal of the electric meter, and performing analog-to-digital conversion on the front voltage signal of the electric meter and the rear voltage signal of the electric meter to obtain a front digital sampling signal of the electric meter and a rear digital sampling signal of the electric meter; the fault judgment algorithm module is used for respectively calculating a front signal peak value of the ammeter and a rear signal peak value of the ammeter according to the front digital sampling signal of the ammeter and the rear digital sampling signal of the ammeter, generating a fault signal and sending the fault signal to the user interface module; the user interface module is used for displaying fault judgment results according to the received different fault signals; the user interface module is also used for triggering the operation sampling module and the fault judging algorithm module to acquire fault signals. The invention is convenient for a user to judge whether the fault section is in the working range of the power supply personnel.
Description
Technical Field
The invention relates to the technical field of post-meter line fault detection, in particular to a rapid post-meter line fault detection device.
Background
The phenomenon generally exists in the distribution network fault rush repair work, and a user cannot conduct self-check when encountering a power failure in the home, and the phenomenon is completely dependent on power supply staff. When the fault occurs, the power supply emergency repair call is first selected, the power distribution emergency repair personnel responds rapidly to the user home, the user home needs to be frequently accessed for investigation, whether the fault section is in the working range of the power supply personnel or not is judged by measuring the voltage and the current of an asset demarcation point (namely, the position of a line switch at the rear section of the ammeter), but the judgment result is that the user equipment is always in fault, the user is required to contact with the electrician by himself, unnecessary power supply personnel to work is caused, and manpower and material resources and the working time of the power supply personnel are consumed.
Disclosure of Invention
Aiming at the defects of the prior art, the invention is convenient for a user to judge whether the fault section is in the working range of the power supply personnel or not, and the user can contact the electrician by himself or herself to solve the problem when judging that the fault section is out of the working range of the power supply personnel, and the user can contact the power supply personnel to solve the problem when the fault section is out of the working range of the power supply personnel, thereby saving manpower, material resources and working time of the power supply personnel.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the invention relates to a fast detection device for line faults after a meter, which comprises the following components:
the sampling module is used for respectively sampling alternating voltage signals at a front section line switch of the electric meter and a rear section line switch of the electric meter by utilizing an alternating voltage amplitude detection algorithm to obtain a front voltage signal of the electric meter and a rear voltage signal of the electric meter, and performing analog-to-digital conversion on the front voltage signal of the electric meter and the rear voltage signal of the electric meter to obtain a front digital sampling signal of the electric meter and a rear digital sampling signal of the electric meter;
the fault judgment algorithm module is used for presetting an ammeter front-stage voltage range under the normal voltage of the ammeter front-stage and an ammeter rear-stage voltage range under the normal voltage of the ammeter rear-stage; respectively calculating a front signal peak value and a rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter; comparing the peak value of the front signal of the ammeter with the front-stage voltage range of the ammeter, and if the peak value of the front signal of the ammeter is not in the front-stage voltage range of the ammeter, generating a fault signal of a fault outside the power supply network and sending the fault signal to the user interface module; comparing the peak value of the post-ammeter signal with the voltage range of the post-ammeter section, and if the peak value of the post-ammeter signal is not in the voltage range of the post-ammeter section, generating a fault signal of a fault in the power supply network and sending the fault signal to the user interface module;
the user interface module is used for displaying fault judgment results according to the received different fault signals; the user interface module is also used for triggering the operation sampling module and the fault judging algorithm module to acquire a fault signal; the fault judging result comprises no fault, an internal power supply network fault, an external power supply network fault and an internal power supply network fault, wherein the no fault is a result of not receiving a fault signal of the internal power supply network fault and a fault signal of the external power supply network fault, the internal power supply network fault is a result of only receiving a fault signal of the internal power supply network fault, the external power supply network fault is a result of only receiving a fault signal of the external power supply network fault, and the internal power supply network fault and the external power supply network fault are a result of simultaneously receiving the fault signals of the internal power supply network fault and the external power supply network fault.
Further, the sampling module comprises a voltage sensor for acquiring an alternating voltage signal and an analog-to-digital converter capable of performing analog-to-digital conversion on the voltage signal.
Further, the alternating voltage amplitude detection algorithm comprises a periodic integration method, a fast FFT algorithm and a DQ algorithm.
The system further comprises a data acquisition and processing module which is arranged between the sampling module and the fault judgment algorithm module and is used for filtering, calibrating and preprocessing the digital sampling signal before the ammeter and the digital sampling signal after the ammeter and inputting the filtered, calibrated and preprocessed digital sampling signal into the fault judgment algorithm module.
Further, the user interface module comprises buttons and a display screen; the button is used for triggering the operation sampling module and the fault judgment algorithm module to acquire a fault signal; the display screen is used for displaying a fault judgment result according to the received fault signal.
Further, the user interface module further comprises an indicator light; the indicator light is used for indicating the state of the device.
Further, the specific methods for respectively calculating the front signal peak value and the rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter are as follows:
three times of digital sampling signals are continuously obtained under the preset sampling frequency through a sampling module, and the signal peak value can be obtained through the following steps:
where U represents a signal peak, U (k 1) represents a first digital sampling signal, U (k 2) represents a second digital sampling signal, U (k 3) represents a third digital sampling signal, and N represents the number of samples in one power frequency cycle.
The method for rapidly detecting the line fault by using the rapid detection device after the meter is as follows:
triggering an operation sampling module and a fault judging algorithm module to acquire a fault signal through a user interface module under the condition that a user encounters power supply interruption;
the fault judgment algorithm module is preset with an ammeter front-stage voltage range under the ammeter front-stage normal voltage and an ammeter rear-stage voltage range under the ammeter rear-stage normal voltage; respectively calculating a front signal peak value and a rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter; comparing the peak value of the front signal of the ammeter with the front-stage voltage range of the ammeter, and if the peak value of the front signal of the ammeter is not in the front-stage voltage range of the ammeter, generating a fault signal of a fault outside the power supply network and sending the fault signal to the user interface module; comparing the peak value of the post-ammeter signal with the voltage range of the post-ammeter section, and if the peak value of the post-ammeter signal is not in the voltage range of the post-ammeter section, generating a fault signal of a fault in the power supply network and sending the fault signal to the user interface module;
and the user interface module displays a fault judgment result according to the received different fault signals.
Compared with the prior art, the invention has the beneficial effects that:
(1) The invention saves time and resources: by avoiding unnecessary power supply personnel from going out, the invention reduces the rush repair process caused by the faults of the user equipment, thereby saving a great deal of time and resources.
(2) The invention improves the rush-repair efficiency: the power supply personnel no longer need to frequently go to the user's home for investigation, and the power supply personnel can be used for handling real power supply network fault with more time to the whole rush repair efficiency has been improved.
(3) The invention optimizes the user experience: the user can obtain the fault judgment result through the intuitive and simple interface, long-time waiting or self-checking is not needed, and the user experience and satisfaction are greatly improved.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the invention, and that other drawings can be obtained according to these drawings without inventive faculty for a person skilled in the art.
Fig. 1 is an overall structural diagram of an embodiment of the present invention.
In the figure: 1. a display screen; 2. a button.
Detailed Description
Embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.
Other advantages and effects of the present disclosure will become readily apparent to those skilled in the art from the following disclosure, which is a description of the embodiments given by way of specific examples. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. All other embodiments, which can be made by one of ordinary skill in the art without inventive effort, based on the embodiments in this disclosure are intended to be within the scope of this disclosure.
As shown in fig. 1, the fast detecting device for post-meter line faults of the present embodiment includes:
the sampling module is used for respectively sampling alternating voltage signals at the front section line switch of the electric meter and the rear section line switch of the electric meter by utilizing an alternating voltage amplitude detection algorithm to obtain a front voltage signal of the electric meter and a rear voltage signal of the electric meter, and performing analog-to-digital conversion on the front voltage signal of the electric meter and the rear voltage signal of the electric meter to obtain a front digital sampling signal of the electric meter and a rear digital sampling signal of the electric meter. The sampling module comprises a voltage sensor for acquiring an alternating voltage signal and an analog-to-digital converter capable of performing analog-to-digital conversion on the voltage signal. The alternating voltage amplitude detection algorithm comprises a periodic integration method, a fast FFT algorithm and a DQ algorithm.
The data acquisition and processing module is arranged between the sampling module and the fault judgment algorithm module and is used for filtering, calibrating and preprocessing the digital sampling signal before the ammeter and the digital sampling signal after the ammeter and then inputting the filtered and calibrated digital sampling signal into the fault judgment algorithm module.
The fault judgment algorithm module is used for presetting an ammeter front-stage voltage range under the normal voltage of the ammeter front-stage and an ammeter rear-stage voltage range under the normal voltage of the ammeter rear-stage; respectively calculating a front signal peak value and a rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter; comparing the peak value of the front signal of the ammeter with the front-stage voltage range of the ammeter, and if the peak value of the front signal of the ammeter is not in the front-stage voltage range of the ammeter, generating a fault signal of a fault outside the power supply network and sending the fault signal to the user interface module; and comparing the peak value of the post-ammeter signal with the voltage range of the post-ammeter section, and if the peak value of the post-ammeter signal is not in the voltage range of the post-ammeter section, generating a fault signal of a fault in the power supply network and sending the fault signal to the user interface module. The specific methods for respectively calculating the front signal peak value and the rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter are as follows:
three times of digital sampling signals are continuously obtained under the preset sampling frequency through a sampling module, and the signal peak value can be obtained through the following steps:
where U represents a signal peak, U (k 1) represents a first digital sampling signal, U (k 2) represents a second digital sampling signal, U (k 3) represents a third digital sampling signal, and N represents the number of samples in one power frequency cycle.
The user interface module is used for displaying fault judgment results according to the received different fault signals; the user interface module is also used for triggering the operation sampling module and the fault judging algorithm module to acquire a fault signal; the fault judging result comprises no fault, an internal power supply network fault, an external power supply network fault and an internal power supply network fault, wherein the no fault is a result of not receiving a fault signal of the internal power supply network fault and a fault signal of the external power supply network fault, the internal power supply network fault is a result of only receiving a fault signal of the internal power supply network fault, the external power supply network fault is a result of only receiving a fault signal of the external power supply network fault, and the internal power supply network fault and the external power supply network fault are a result of simultaneously receiving the fault signals of the internal power supply network fault and the external power supply network fault. The user interface module comprises buttons 2 and a display screen 1. The button 1 is used for triggering the operation sampling module and the fault judgment algorithm module to acquire a fault signal. The display screen 2 is used for displaying a fault judgment result according to the received fault signal. The user interface module further comprises an indicator light; the indicator light is used for indicating the state of the device.
User power failure: the user encounters a power outage situation at home, and the power supply is interrupted, possibly due to a grid fault or a user equipment fault.
User operation device: the user presses the "debug" button on the device, triggering the fault determination process.
Data acquisition and processing: the voltage sensor and the current sensor are respectively used for measuring voltage and current values, sampling alternating voltage signals at the front section line switch of the ammeter and the rear section line switch of the ammeter to obtain a front ammeter voltage signal and a rear ammeter voltage signal, and converting the analog signals into digital signals. The data acquisition and processing module performs filtering, calibration and preprocessing to obtain accurate voltage and current data.
And (3) analyzing a fault judgment algorithm: the fault judgment algorithm module uses real-time voltage and current data to preset an ammeter front-stage voltage range under the normal voltage of the ammeter front-stage and an ammeter rear-stage voltage range under the normal voltage of the ammeter rear-stage; respectively calculating a front signal peak value and a rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter; comparing the peak value of the front signal of the ammeter with the front-stage voltage range of the ammeter, and if the peak value of the front signal of the ammeter is not in the front-stage voltage range of the ammeter, generating a fault signal of a fault outside the power supply network and sending the fault signal to the user interface module; and comparing the peak value of the post-ammeter signal with the voltage range of the post-ammeter section, and if the peak value of the post-ammeter signal is not in the voltage range of the post-ammeter section, generating a fault signal of a fault in the power supply network and sending the fault signal to the user interface module.
And (3) judging results show that: the judging result is displayed on the display screen 1 through the user interface module, and data such as the voltage before the meter, the current before the meter, the voltage after the meter, the current after the meter and the like can be displayed. The result indicates clearly whether the fault is within the power supply range.
User decision: the user decides the next action according to the displayed judging result. If the device judges that the fault is not in the power supply network, the user can select to contact the professional electrician for fault treatment; if the fault is within the power supply network, the user may choose to contact the power supply personnel.
The foregoing has described in detail the device for quickly detecting a post-meter line fault provided by the present invention, and specific examples have been applied herein to illustrate the principles and embodiments of the present invention, and the above description of the examples is only for helping to understand the method and core idea of the present invention; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present invention, the present description should not be construed as limiting the present invention in view of the above.
Claims (8)
1. Quick detection device of circuit trouble behind table, its characterized in that includes:
the sampling module is used for respectively sampling alternating voltage signals at a front section line switch of the electric meter and a rear section line switch of the electric meter by utilizing an alternating voltage amplitude detection algorithm to obtain a front voltage signal of the electric meter and a rear voltage signal of the electric meter, and performing analog-to-digital conversion on the front voltage signal of the electric meter and the rear voltage signal of the electric meter to obtain a front digital sampling signal of the electric meter and a rear digital sampling signal of the electric meter;
the fault judgment algorithm module is used for presetting an ammeter front-stage voltage range under the normal voltage of the ammeter front-stage and an ammeter rear-stage voltage range under the normal voltage of the ammeter rear-stage; respectively calculating a front signal peak value and a rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter; comparing the peak value of the front signal of the ammeter with the front-stage voltage range of the ammeter, and if the peak value of the front signal of the ammeter is not in the front-stage voltage range of the ammeter, generating a fault signal of a fault outside the power supply network and sending the fault signal to the user interface module; comparing the peak value of the post-ammeter signal with the voltage range of the post-ammeter section, and if the peak value of the post-ammeter signal is not in the voltage range of the post-ammeter section, generating a fault signal of a fault in the power supply network and sending the fault signal to the user interface module;
the user interface module is used for displaying fault judgment results according to the received different fault signals; the user interface module is also used for triggering the operation sampling module and the fault judging algorithm module to acquire a fault signal; the fault judging result comprises no fault, an internal power supply network fault, an external power supply network fault and an internal power supply network fault, wherein the no fault is a result of not receiving a fault signal of the internal power supply network fault and a fault signal of the external power supply network fault, the internal power supply network fault is a result of only receiving a fault signal of the internal power supply network fault, the external power supply network fault is a result of only receiving a fault signal of the external power supply network fault, and the internal power supply network fault and the external power supply network fault are a result of simultaneously receiving the fault signals of the internal power supply network fault and the external power supply network fault.
2. The post-meter line fault quick detection device of claim 1, wherein the sampling module comprises a voltage sensor that obtains an ac voltage signal and an analog-to-digital converter that is capable of analog-to-digital converting the voltage signal.
3. The fast post-meter line fault detection device of claim 1, wherein the ac voltage magnitude detection algorithm comprises a periodic integration method, a fast FFT algorithm, a DQ algorithm.
4. The device for quickly detecting the line fault after the meter according to claim 1, further comprising a data acquisition and processing module, which is arranged between the sampling module and the fault judging algorithm module and is used for filtering, calibrating and preprocessing the digital sampling signals before the meter and the digital sampling signals after the meter and then inputting the filtered and calibrated digital sampling signals into the fault judging algorithm module.
5. The rapid detection apparatus for post-meter line faults of claim 1, wherein said user interface module comprises a button and a display screen; the button is used for triggering the operation sampling module and the fault judgment algorithm module to acquire a fault signal; the display screen is used for displaying a fault judgment result according to the received fault signal.
6. The rapid detection apparatus for post-meter line faults of claim 1, wherein said user interface module further comprises an indicator light; the indicator light is used for indicating the state of the device.
7. The rapid line fault detection device according to claim 1, wherein the specific methods for calculating the pre-meter signal peak value and the post-meter signal peak value according to the pre-meter digital sampling signal and the post-meter digital sampling signal respectively are:
three times of digital sampling signals are continuously obtained under the preset sampling frequency through a sampling module, and the signal peak value can be obtained through the following steps:
where U represents a signal peak, U (k 1) represents a first digital sampling signal, U (k 2) represents a second digital sampling signal, U (k 3) represents a third digital sampling signal, and N represents the number of samples in one power frequency cycle.
8. The method of rapid detection using the rapid detection apparatus of any one of claims 1 to 7 is as follows:
triggering an operation sampling module and a fault judging algorithm module to acquire a fault signal through a user interface module under the condition that a user encounters power supply interruption;
the fault judgment algorithm module is preset with an ammeter front-stage voltage range under the ammeter front-stage normal voltage and an ammeter rear-stage voltage range under the ammeter rear-stage normal voltage; respectively calculating a front signal peak value and a rear signal peak value of the ammeter according to the front digital sampling signal and the rear digital sampling signal of the ammeter; comparing the peak value of the front signal of the ammeter with the front-stage voltage range of the ammeter, and if the peak value of the front signal of the ammeter is not in the front-stage voltage range of the ammeter, generating a fault signal of a fault outside the power supply network and sending the fault signal to the user interface module; comparing the peak value of the post-ammeter signal with the voltage range of the post-ammeter section, and if the peak value of the post-ammeter signal is not in the voltage range of the post-ammeter section, generating a fault signal of a fault in the power supply network and sending the fault signal to the user interface module;
and the user interface module displays a fault judgment result according to the received different fault signals.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311598230.8A CN117452144A (en) | 2023-11-28 | 2023-11-28 | Quick detection device for line faults behind meter |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311598230.8A CN117452144A (en) | 2023-11-28 | 2023-11-28 | Quick detection device for line faults behind meter |
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| CN117452144A true CN117452144A (en) | 2024-01-26 |
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| CN202311598230.8A Pending CN117452144A (en) | 2023-11-28 | 2023-11-28 | Quick detection device for line faults behind meter |
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- 2023-11-28 CN CN202311598230.8A patent/CN117452144A/en active Pending
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