CN111025006B - Non-contact voltage detection and phase recognition device - Google Patents
Non-contact voltage detection and phase recognition device Download PDFInfo
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- CN111025006B CN111025006B CN201911330581.4A CN201911330581A CN111025006B CN 111025006 B CN111025006 B CN 111025006B CN 201911330581 A CN201911330581 A CN 201911330581A CN 111025006 B CN111025006 B CN 111025006B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
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- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract
The invention relates to a non-contact voltage detection and phase recognition device, and belongs to the technical field of electric power engineering live detection and monitoring. The device comprises a sensor detection device, a bracket, a detector and a handheld rod; the detector is positioned right below the sensor detection device and is connected with the sensor detection device through a bracket; the detector is provided with an LED indicator light, a display screen, a switch, an instrument shell, a laser emission receiver, an audible alarm and a control circuit; the top end of the handheld rod is fixedly connected with the bottom of the detector; insulating rubber is sleeved outside the handheld rod. The invention adopts non-contact measurement, can calculate the voltage of the maintenance line, judges the electrified condition of each phase of power transmission line and gives sound-light alarm prompt. The device has the advantages of reliable electricity testing, safe operation and the like.
Description
Technical Field
The invention belongs to the technical field of electrified detection and monitoring of electric power engineering, and particularly relates to a non-contact voltage detection and phase recognition device.
Background
The high-voltage electroscope is widely applied to various high-voltage equipment in an electric power system, particularly, whether the high-voltage equipment is electrified or not directly affects the personal safety of operators, in order to prevent the misoperation of the operators from causing a series of safety problems, the electric power system strictly requires to accurately detect the high-voltage electrification condition, and the high-voltage electroscope plays an extremely important role in the safety production of the electric power industry.
The ordinary high-voltage electroscope is only used for warning and reminding maintainers of electrification of equipment. The common high-voltage electroscope is convenient to use, and only the handle of the electroscope is needed to be held by hand, and the contact of the electroscope is used for touching the electrified part of the high-voltage equipment. The existing contact type high-voltage electroscope in the market threatens the life safety of maintainers due to direct contact between the electroscope and a high-voltage line, possibly due to insulation aging of the electroscope, short circuit of elements and the like.
The voltage measurement type electroscope can measure the voltage of the high-voltage equipment, and is frequently used when faults are searched and the running condition of the equipment is detected. However, the current voltage measurement electroscope needs to be connected with a grounding wire when in use, and is not convenient to use like a high-voltage indication electroscope. The other type of voltage measurement electroscope does not need to be connected with a grounding wire, but needs to touch a low-voltage electrode in use, so that the electroscope is unsafe. Such electroscope is not in compliance with industry work safety regulations. In addition, no matter the current existing contact or non-contact electroscope, the phase can not be identified, so how to overcome the defects of the prior art is a problem to be solved urgently in the technical field of the current electric power engineering live detection and monitoring.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a non-contact voltage detection and phase identification device, which solves the problem that a contact electroscope threatens the safety of maintainers, adopts the electric field induction principle, does not contact a high-voltage line, remotely detects whether the line is electrified or not, and can identify the phase; meanwhile, the problem that the conventional high-voltage electroscope is inconvenient to adopt electroscope with the specification corresponding to the rated voltage of the circuit electroscope for different voltage grades is solved, and the high-voltage electroscope is easy to popularize and apply.
The non-contact voltage detection and phase recognition device comprises a sensor detection device, a bracket, a detector and a handheld rod;
the detector is positioned right below the sensor detection device and is connected with the sensor detection device through a bracket;
the sensor detection device comprises a device shell and a plurality of electric field induction sensors arranged in the device shell; the detector comprises an LED indicator light, a display screen, a switch, an instrument shell, a laser emission receiver, an audible alarm and a control circuit;
the LED indicator lamp, the display screen, the change-over switch, the laser emission receiver and the sound alarm are all arranged on the instrument shell, and the control circuit is positioned inside the instrument shell;
the top end of the handheld rod is fixedly connected with the bottom of the detector, a battery bin is arranged on the handheld rod, and a battery is mounted in the battery bin and used for supplying electric energy to the detector; insulating rubber is sleeved outside the handheld rod.
Further, preferably, the LED indicator, the display screen and the switch are all mounted on the upper surface of the instrument housing; the laser emitting receiver and the sound alarm are arranged on the lower surface of the instrument shell.
Further, preferably, the battery is a lithium battery.
Further, preferably, the control circuit comprises a voltage gear circuit, an amplifying and filtering circuit, a voltage boosting circuit, a bidirectional switch, an A/D module, a self-checking circuit, an alarm circuit, a voltage phase display circuit and a single chip microcomputer;
the electromagnetic field sensor is connected with the input end of the voltage gear circuit;
the voltage gear circuit, the amplifying and filtering circuit and the voltage boosting circuit are sequentially connected;
the voltage boosting circuit is respectively connected with the self-checking circuit and the A/D module through the bidirectional switch;
the A/D module is also connected with the singlechip and the laser transmitting and receiving device respectively;
the output end of the self-checking circuit is connected with the input end of the alarm circuit;
the single chip microcomputer is respectively connected with the input end of the alarm circuit and the input end of the voltage phase display circuit;
the output end of the alarm circuit is respectively connected with the sound alarm and the LED indicator light;
the output end of the voltage phase display circuit is connected with the display screen;
the battery is connected with the singlechip.
Further, preferably, the audible alarm is a buzzer.
Further, it is preferable that the number of the electric field induction sensors is 5 and is uniformly arranged.
The invention can select the self-checking mode and the electricity testing mode through the adjusting switch, thereby improving the electricity testing reliability.
The device can simultaneously measure five times below the power transmission line during measurement, the average value of the five times is compared, and the single chip automatically judges the electrification condition of each phase of the power transmission line according to the measurement result.
The device provided by the invention contains five sensors, can simultaneously measure the voltage value of a certain position of the power transmission line, and can record data corresponding to the position and the voltage value to the maximum extent.
The device is provided with a laser transmitting and receiving device, and the testing distance quantity is displayed on a display screen.
The principle of judging each phase of power transmission line by the device is as follows: firstly, MATLAB software is utilized to carry out simulation analysis on seven conditions of all electrification, two-phase conduction, one-phase conduction and the like to obtain a waveform, and a coding table is generated according to the waveform and a ratio rule. The generation rule of the coding table is that twenty-five points are averagely taken below the power transmission line, the average value of every five points is recorded as (I), (II), (III), (IV) and (V), if (I)/II is more than or equal to 1, the average value is recorded as (1), (I)/II)<1，Recording as 0, analogizing, sequentially judging the ratio to generate a four-digit binary code, and recording the voltage below the neutral line power transmission line as V0The maximum value of the measurement is denoted as VmaxIf V is0/VmaxIs more than or equal to 0.8, is marked as 1, if V0/Vmax<0.8, it is marked as 0 as a special bit. And keeping the measuring point at the same height according to the laser testing distance, measuring a voltage value below the power transmission line, and if the generated code value is the same as a code value prestored by the system, judging the electrification condition of each phase of line. Specifically, the results are shown in Table 1.
TABLE 1
The self-checking function of the invention is to check whether each branch circuit of the tester works normally, and the self-checking operation process is as follows: when the change-over switch is dialed to a 'TEST' gear, the audible alarm should be sounded, and the LED indicator light should be on, indicating that the device of the present invention is operating. If the beep is low and the LED indicator lights are dark, it may be that the battery is low.
Compared with the prior art, the invention has the beneficial effects that:
compared with the existing high-voltage electroscope, the device provided by the invention adopts non-contact electroscopy, can estimate the voltage value of the line, and judges the electrification condition of each phase, so that the line electroscopy is safer and more reliable. Different with traditional electroscope, it need not just can judge with high tension transmission line contact whether electrified in the testing process, can audio-visually display test result, and ungrounded line need not to measure the circuit height, does not consider test line sag influence, can provide different measuring voltage gears, and is more convenient than traditional electroscope during the use.
Drawings
FIG. 1 is a schematic structural diagram of a non-contact voltage detecting and phase identifying apparatus according to the present invention;
FIG. 2 is a schematic diagram of a control circuit;
FIG. 3 is an ABC three-phase full-live simulation diagram;
FIG. 4 is a two-phase power-on one-phase power-on simulation diagram;
FIG. 5 is a one-phase electrical two-phase charging simulation diagram.
Detailed Description
The present invention will be described in further detail with reference to examples.
It will be appreciated by those skilled in the art that the following examples are illustrative of the invention only and should not be taken as limiting the scope of the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The materials or equipment used are not indicated by manufacturers, and all are conventional products available by purchase.
As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.
In the description of the present invention, "a plurality" means two or more unless otherwise specified. The terms "inner," "upper," "lower," and the like, refer to an orientation or a state relationship based on that shown in the drawings, which is for convenience in describing and simplifying the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "provided" are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. To those of ordinary skill in the art, the specific meanings of the above terms in the present invention are understood according to specific situations.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
As shown in fig. 1 to 2, the non-contact voltage detection and phase recognition device includes a sensor detection device 1, a bracket 2, a detector 9 and a handheld rod 5;
the detector 9 is positioned right below the sensor detection device 1 and is connected with the sensor detection device 1 through the bracket 2;
the sensor detection device 1 comprises a device shell 10 and a plurality of electric field induction sensors 11, preferably 5 electric field induction sensors, which are uniformly distributed and used for space positioning, wherein the electric field induction sensors 11 are arranged in the device shell 10; the detector 9 comprises an LED indicator lamp 3, a display screen 4, a switch 6, an instrument shell 7, a laser transmitting receiver 8, an audible alarm 12 and a control circuit;
the LED indicator lamp 3, the display screen 4, the change-over switch 6, the laser transmitting receiver 8 and the sound alarm 12 are all arranged on the instrument shell 7, and the control circuit is positioned inside the instrument shell 7;
the top end of the handheld rod 5 is fixedly connected with the bottom of the detector 9, a battery compartment 13 is arranged on the handheld rod 5, and a battery is arranged in the battery compartment 13 and used for supplying electric energy to the detector 9; insulating rubber is sleeved outside the handheld rod 5.
The LED indicator lamp 3, the display screen 4 and the switch 6 are all arranged on the upper surface of the instrument shell 7; laser emission receiver 8, audible alarm 12 install in the lower surface of instrument casing 7, are convenient for examine electric during operation staff in time and discover alarm information.
Preferably, the audible alarm 12 is a buzzer. The battery is a 5V lithium battery.
The control circuit comprises a voltage gear circuit, an amplifying and filtering circuit, a voltage boosting circuit, a two-way switch, an A/D module, a self-checking circuit, an alarm circuit, a voltage phase display circuit and a single chip microcomputer;
the electromagnetic field sensor 11 is connected with the input end of the voltage gear circuit;
the voltage gear circuit, the amplifying and filtering circuit and the voltage boosting circuit are sequentially connected;
the voltage boosting circuit is respectively connected with the self-checking circuit and the A/D module through the bidirectional switch;
the A/D module is also connected with the singlechip and the laser transmitting and receiving device respectively;
the output end of the self-checking circuit is connected with the input end of the alarm circuit;
the single chip microcomputer is respectively connected with the input end of the alarm circuit and the input end of the voltage phase display circuit;
the output end of the alarm circuit is respectively connected with the sound alarm 12 and the LED indicator lamp 3;
the output end of the voltage phase display circuit is connected with the display screen 4;
the battery is connected with the singlechip and used for driving the singlechip so as to start the device.
The voltage gear circuit can obtain line voltage according to the signal that electromagnetic field sensor 11 gathered, later select different voltage gears according to line voltage grade to measure, avoids the trouble of changing electroscope, convenient to use, safe and reliable and work efficiency height.
The amplifying and filtering circuit is used for carrying out voltage amplification on the acquired voltage signals and filtering out high-frequency interference except 50 Hz;
the voltage boosting circuit converts signals acquired by the sensor into direct current signals so as to be identified by the A/D module;
the A/D module converts the acquired voltage into high-precision reference voltage;
the bidirectional switch is used for selecting an electricity testing mode and a self-checking mode according to requirements;
the self-checking circuit is to add an induction voltage outside the electric field sensor to observe whether the function of sending the sound and light alarm is normal;
the single chip microcomputer samples the processed voltage signals through the A/D module, and the single chip microcomputer adopts an stm32 single chip microcomputer with sampling precision meeting requirements. The power supply adopts a 5V storage battery for power supply. According to the bidirectional switch, a self-checking mode and an electricity testing mode can be selected. The signal received by the laser transmitter-receiver is sampled to the singlechip through the A/D module, the height from the ground is displayed on a display screen through the processing of the singlechip, whether the line is electrified or not is judged through the singlechip during measurement, and the display screen displays the electrification condition and the line voltage value of each phase; if the LED lamp is electrified, the alarm circuit is triggered, then the LED lamp is turned on, and the sound alarm gives an alarm.
Under normal illumination and background noise of the alarm circuit, the device gives clear and easily-distinguished visual and auditory indications after the starting voltage is reached;
the voltage phase display circuit displays corresponding data by using a display screen;
the display screen of the present invention may be a digital display screen, but is not limited thereto.
The device of the invention realizes the functions of voltage phase measurement, display and alarm prompt based on the single chip microcomputer.
In the embodiment shown in fig. 3, 4, and 5, the electrified condition of each phase of power transmission line under the simulated power transmission line is calculated by using a 220kV high-voltage power transmission line, the wire uses LGJ-300/40, the power transmission line is a single-circuit three-phase power transmission line with the same tower, the three-phase power transmission line is horizontally arranged, the wire phase distance L is 5m, the ground height H of the middle phase wire sag is 10m, and the phase a, the phase B, and the phase C are sequentially arranged from left to right. The equivalent radius of the three-phase power conductors is about 0.012 m.
Preferably, the laser transmitter-receiver has a self-calibration function. The laser emitting receiver emits laser during measurement, the height of a measuring point from the ground is locked, and a ranging result can be displayed on the display screen, so that the height of the measuring point from the ground is guaranteed, a voltage value of a certain height under a detection power transmission line is sent to the single chip microcomputer, and through a coding table judgment mechanism in the system, the electrification condition and the voltage value of each phase of the power transmission line can be accurately judged and displayed on the display screen.
The device of the invention needs five times of detection during detection, records data in the single chip microcomputer, compares the average value of each measurement, then codes, and the codes of special bits also compare the voltage value below the midline of the measurement data and the maximum value of the measurement voltage, and the five times of measurement totals twenty-five data, thus ensuring the accuracy of the measurement.
The instrument shell is of a round table structure, shielding materials are selected to prevent surrounding electromagnetic fields from interfering the device to collect voltage, the device can measure a line to be tested within 15 degrees of inclination according to the testing distance and the national anti-interference standard, and the sensitivity of electroscope electroscopy is improved.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (5)
1. The non-contact voltage detection and phase identification device is characterized by comprising a sensor detection device (1), a bracket (2), a detector (9) and a handheld rod (5);
the detector (9) is positioned right below the sensor detection device (1) and is connected with the sensor detection device (1) through the bracket (2);
the sensor detection device (1) comprises a device shell (10) and a plurality of electric field induction sensors (11) arranged inside the device shell (10); the detector (9) comprises an LED indicator lamp (3), a display screen (4), a change-over switch (6), an instrument shell (7), a laser emission receiver (8), an audible alarm (12) and a control circuit;
the LED indicating lamp (3), the display screen (4), the change-over switch (6), the laser emission receiver (8) and the sound alarm (12) are all arranged on the instrument shell (7), and the control circuit is positioned inside the instrument shell (7);
the top end of the handheld rod (5) is fixedly connected with the bottom of the detector (9), a battery bin (13) is arranged on the handheld rod (5), a battery is mounted in the battery bin (13), and the battery is used for supplying electric energy to the detector (9); insulating rubber is sleeved outside the handheld rod (5);
the control circuit comprises a voltage gear circuit, an amplifying and filtering circuit, a voltage boosting circuit, a two-way switch, an A/D module, a self-checking circuit, an alarm circuit, a voltage phase display circuit and a single chip microcomputer;
the electric field induction sensor (11) is connected with the input end of the voltage gear circuit;
the voltage gear circuit, the amplifying and filtering circuit and the voltage boosting circuit are sequentially connected;
the voltage boosting circuit is respectively connected with the self-checking circuit and the A/D module through the bidirectional switch;
the A/D module is also connected with the singlechip and the laser transmitting and receiving device respectively;
the output end of the self-checking circuit is connected with the input end of the alarm circuit;
the single chip microcomputer is respectively connected with the input end of the alarm circuit and the input end of the voltage phase display circuit;
the output end of the alarm circuit is respectively connected with the sound alarm (12) and the LED indicating lamp (3);
the output end of the voltage phase display circuit is connected with the display screen (4);
the battery is connected with the singlechip;
twenty-five points are averagely taken below the power transmission line, and the average value of every five points is recorded as (i), (ii), (iii), (iv) and (v), if (i)/ii is more than or equal to 1, the average value is recorded as (1), (i)/ii)<1, recording as 0, analogizing, sequentially judging the ratio to generate a four-digit binary code, and recording the voltage below the neutral line power transmission line as V0The maximum value of the measurement is denoted as VmaxIf V is0/VmaxIs more than or equal to 0.8, is marked as 1, if V0/Vmax＜0.8，Then it is marked as 0 as the special bit; keeping the measuring point at the same height according to the laser testing distance, measuring a voltage value below the power transmission line, and if the generated code value is the same as a code value prestored by a system, judging the electrification condition of each phase of line; as shown in table 1;
TABLE 1
2. The non-contact voltage detection and phase identification device according to claim 1, wherein the LED indicator lamp (3), the display screen (4) and the change-over switch (6) are all arranged on the upper surface of the instrument shell (7); the laser emitting receiver (8) and the sound alarm (12) are both arranged on the lower surface of the instrument shell (7).
3. The apparatus according to claim 1, wherein the battery is a 5V lithium battery.
4. The apparatus for non-contact voltage detection and phase identification as claimed in claim 1, wherein the audible alarm (12) is a buzzer.
5. The non-contact voltage detecting and phase discriminating device as claimed in claim 1, wherein the number of the electric field induction sensors (11) is 5 and is uniformly arranged.
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| CN201911330581.4A CN111025006B (en) | 2019-12-20 | 2019-12-20 | Non-contact voltage detection and phase recognition device |
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| CN201911330581.4A CN111025006B (en) | 2019-12-20 | 2019-12-20 | Non-contact voltage detection and phase recognition device |
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| CN111766434A (en) * | 2020-08-06 | 2020-10-13 | 苏州康力丰纳米科技有限公司 | High-voltage safety indicating device based on nematic polymer polarization and application method |
| CN112362969B (en) * | 2020-10-15 | 2024-01-12 | 国网江苏省电力有限公司江阴市供电分公司 | Phase detection method |
| CN114113756A (en) * | 2021-10-12 | 2022-03-01 | 广西电网有限责任公司桂林供电局 | Intelligent visualized voltage device and method for switch cabinet sensor |
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| CN101487858B (en) * | 2009-02-20 | 2010-11-10 | 国网电力科学研究院 | 1000kV extra-high voltage AC non-contact type electricity checking method and apparatus |
| CN201562007U (en) * | 2009-12-08 | 2010-08-25 | 武汉大学 | Intelligent non-contact type high-voltage electroscope |
| KR101180237B1 (en) * | 2010-12-28 | 2012-09-05 | 인천대학교 산학협력단 | The live line electroscope which uses the magnetic field |
| CN102645573B (en) * | 2012-05-11 | 2015-05-13 | 西安电子科技大学 | Noncontact ultrahigh voltage electricity detector |
| US20160209454A1 (en) * | 2015-01-19 | 2016-07-21 | Patrick McCammon | Wireless Power Line Sensor |
| CN105137161A (en) * | 2015-07-17 | 2015-12-09 | 恒同(中国)有限公司 | Digital composite functional high-voltage electroscope |
| CN205263180U (en) * | 2015-12-09 | 2016-05-25 | 福建爱迪生科技有限公司 | Electroscope for electrical power rush -repair |
| US10352967B2 (en) * | 2016-11-11 | 2019-07-16 | Fluke Corporation | Non-contact electrical parameter measurement systems |
| CN107741521B (en) * | 2017-11-30 | 2023-06-09 | 福州大学 | Three-phase system non-contact high-voltage electrification judging and indicating device and method thereof |
| CN208013284U (en) * | 2018-03-20 | 2018-10-26 | 云南电网有限责任公司西双版纳供电局 | A kind of Adjustable device formula high voltage electroscope |
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