CN110618311A - Direct current ammeter based on electric wire netting detects direct current system ground fault - Google Patents
Direct current ammeter based on electric wire netting detects direct current system ground fault Download PDFInfo
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- CN110618311A CN110618311A CN201911047839.XA CN201911047839A CN110618311A CN 110618311 A CN110618311 A CN 110618311A CN 201911047839 A CN201911047839 A CN 201911047839A CN 110618311 A CN110618311 A CN 110618311A
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- module
- direct current
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- unit
- detecting
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- 238000001514 detection method Methods 0.000 claims abstract description 28
- 238000006243 chemical reaction Methods 0.000 claims abstract description 22
- 230000000087 stabilizing effect Effects 0.000 claims description 19
- 230000008878 coupling Effects 0.000 claims description 12
- 238000010168 coupling process Methods 0.000 claims description 12
- 238000005859 coupling reaction Methods 0.000 claims description 12
- 238000002955 isolation Methods 0.000 claims description 9
- 238000010586 diagram Methods 0.000 description 9
- 230000006641 stabilisation Effects 0.000 description 5
- 238000011105 stabilization Methods 0.000 description 5
- 238000005259 measurement Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 230000005693 optoelectronics Effects 0.000 description 2
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 1
- 101000983338 Solanum commersonii Osmotin-like protein OSML15 Proteins 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 229910001416 lithium ion Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000013024 troubleshooting Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
- Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
- Y04S10/00—Systems supporting electrical power generation, transmission or distribution
- Y04S10/50—Systems or methods supporting the power network operation or management, involving a certain degree of interaction with the load-side end user applications
- Y04S10/52—Outage or fault management, e.g. fault detection or location
Abstract
The invention discloses a direct current ammeter for detecting a ground fault of a direct current system based on a power grid, which comprises an MCU module, an analog-to-digital conversion module, a current detection module, a display module and a power supply module, wherein the signal output end of the MCU module is respectively connected with the signal input ends of the current detection module and the display module; above-mentioned direct current ammeter sets up through the cooperation of MCU module, analog-to-digital conversion module, current detection module, display module, power module, can use this direct current ammeter to replace the function of universal meter electric current shelves, can reduce operating time by a wide margin, reduces the risk of misuse with universal meter resistance shelves in the work, simultaneously, can alone operate, improves work efficiency, increases economic benefits.
Description
Technical Field
The invention relates to the technical field of direct current meters, in particular to a direct current meter for detecting a ground fault of a direct current system based on a power grid.
Background
The direct current system is an ungrounded system, and once the direct current system is grounded, the risk of equipment misoperation and device failure can occur, which can cause serious economic loss of a power grid. Due to the fact that the insulation of cable equipment and the like is aged or the local water inflow of equipment in rainy seasons causes nonreactive factors such as poor insulation, and the like, direct current grounding inevitably occurs.
At present, when a direct-current grounding fault occurs in an operating transformer substation, when a related grounding position range is determined, and specific cables are searched behind a protection screen, a measurement and control screen and a mechanism terminal box, no matter the conventional disconnecting and checking multimeter is used for measurement, or a direct-current grounding finder is used for searching a loop or is grounded at multiple points, the disconnecting and checking must be carried out on a signal line or a power supply public end. At this moment, the direct current power supply in the screen inner box has no power failure, so when the work of removing the stitches and troubleshooting is carried out, the wiring and binding are needed to be removed by one person, the current is measured by a universal meter, and whether the current is normal or not is needed to be observed by the universal meter. The method is time-consuming and labor-consuming to implement, inconvenient to operate and has the risk of equipment tripping and easy accidental touch caused by misusing the resistance gear of the multimeter.
Disclosure of Invention
Based on the technical scheme, the invention provides the direct current ammeter for detecting the ground fault of the direct current system based on the power grid.
The utility model provides a direct current ammeter based on electric wire netting detects direct current system ground fault, includes MCU module, analog-to-digital conversion module, current detection module, display module, power module, the signal output part of MCU module is connected with current detection module and display module's signal input part respectively, analog-to-digital conversion module's signal output part is connected with MCU module's signal input part, and current detection module's signal output part is connected with analog-to-digital conversion module's signal input part, power module provides the electric energy for MCU module, analog-to-digital conversion module, current detection module, display module respectively.
One embodiment is that the power module includes a power supply unit, a charging unit, a first voltage stabilization unit, a second voltage stabilization unit, and an isolation power supply, wherein a signal output terminal of the power supply unit is connected to a signal input terminal of the charging unit, a signal output terminal of the charging unit is connected to a signal input terminal of the first voltage stabilization unit, and a signal output terminal of the first voltage stabilization unit is connected to signal input terminals of the second voltage stabilization unit and the isolation power supply, respectively.
In one embodiment, the dc current meter for detecting the ground fault of the dc system based on the power grid further includes a photoelectric coupling control module, a signal input end of the photoelectric coupling control module is connected with a signal output end of the MCU module, and a signal output end of the photoelectric coupling control module is connected with a signal input end of the current detection module.
One embodiment of the invention is that the direct current ammeter for detecting the ground fault of the direct current system based on the power grid further comprises a lamp control module, wherein the lamp control module comprises a lighting unit and an indicator light unit, and signal input ends of the lighting unit and the indicator light unit are respectively connected with a signal output end of the MCU module.
In one embodiment, the power module further includes a power switch unit for turning on and off the circuit.
One embodiment is that the chip model of the MCU module is STM32F030K6T 6.
In one embodiment, the chip model of the second voltage stabilizing unit is LD1117 ASTR.
In one embodiment, the analog-to-digital conversion module has a chip model of ADC 1118.
In one embodiment, the chip model of the charging unit is TP 4056.
Above-mentioned direct current ammeter based on electric wire netting detects direct current system ground fault sets up through the cooperation of MCU module, analog-to-digital conversion module, current detection module, display module, power module, can use this direct current ammeter to replace the function of universal meter electric current shelves, can reduce operating time by a wide margin, reduces the risk that the misuse was used universal meter resistance shelves in the work, simultaneously, can alone operate, improves work efficiency, increases economic benefits.
Drawings
Fig. 1 is a schematic structural diagram of a dc ammeter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention;
fig. 2 is a circuit diagram of an MCU module of a dc current meter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 3 is a circuit diagram of an analog-to-digital conversion module of a dc current meter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 4 is a circuit diagram of a current detection module of a dc current meter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 5 is a circuit diagram of a display module of a dc current meter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 6 is a circuit diagram of a power module of a dc current meter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 7 is a circuit diagram of a photoelectric coupling control module of a dc ammeter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 8 is a circuit diagram of a lamp control module of a dc current meter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1;
fig. 9 is a thin film key circuit diagram of a dc ammeter for detecting a ground fault of a dc system based on a power grid according to an embodiment of the present invention in fig. 1.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. 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. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.
Unless defined otherwise, all 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. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
As shown in fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, a dc ammeter for detecting a ground fault of a dc system based on a power grid includes an MCU module 10, an analog-to-digital conversion module 20, a current detection module 30, a display module 40, and a power module 50, wherein a signal output end of the MCU module 10 is connected to signal input ends of the current detection module 30 and the display module 40, a signal output end of the analog-to-digital conversion module 20 is connected to a signal input end of the MCU module 10, a signal output end of the current detection module 30 is connected to a signal input end of the analog-to-digital conversion module 20, and the power module 50 provides electric energy to the MCU module 10, the analog-to-digital conversion module 20, the current detection module 30.
When the current detection is performed on the load, the current detection module 30 is connected in series with one end of the load, and the other end of the load is connected to the anode of the external power supply through the telescopic wire. The current detection module 30 detects a current value of the load and then transmits the current value to the analog-to-digital conversion module 20, the analog-to-digital conversion module 20 converts the received analog signal into a digital signal and then transmits the digital signal to the MCU module 10, and the MCU module 10 controls the display module 40 to display a specific numerical value to complete the measurement.
Like this, a direct current ammeter based on electric wire netting detects direct current system ground fault sets up through MCU module 10, analog-to-digital conversion module 20, current detection module 30, display module 40, power module 50's cooperation, can use this direct current ammeter to replace the function of universal meter electric current shelves, can reduce operating time by a wide margin, reduces the risk of misuse universal meter resistance shelves in the work, simultaneously, can alone operate, improves work efficiency, increases economic benefits.
As shown in fig. 6, further, in order to ensure that the dc current table supplies power to different modules, the power module 50 includes a power supply unit 51, a charging unit 52, a first voltage stabilizing unit 53, a second voltage stabilizing unit 54, and an isolation power supply 55, wherein a signal output terminal of the power supply unit 51 is connected to a signal input terminal of the charging unit 52, a signal output terminal of the charging unit 52 is connected to a signal input terminal of the first voltage stabilizing unit 53, and a signal output terminal of the first voltage stabilizing unit 53 is connected to signal input terminals of the second voltage stabilizing unit 54 and the isolation power supply 55, respectively.
The power supply unit 51 is a USB charging interface, outputs a voltage of 5V, and is connected to one end of a resistor R31 of the charging unit 52, an ISET pin of the charging unit 52 is connected to one end of a resistor R6, one end of a capacitor C18 is connected to an IN + pin of the first voltage stabilizing unit 53, and an OUT + pin is connected to an IN pin of the second voltage stabilizing unit 54 and a VIN + pin of the isolation power supply 55, respectively.
Like this, the USB interface output that charges is after 5V voltage, send behind charging unit 52 for first voltage stabilizing unit 53 steady voltage be 5V voltage, give the MCU module power supply after converting 5V voltage into 3.3V voltage through second voltage stabilizing unit 54 again, first voltage stabilizing unit 53 converts voltage into 12V voltage through isolation power supply 55 and gives other module power supplies, has guaranteed to supply power for a plurality of modules simultaneously, simple structure, convenient to use.
As shown in fig. 7, further, in order to avoid signal transmission from being interfered and protect the single chip microcomputer, the dc current meter for detecting the ground fault of the dc system based on the power grid further includes a photocoupler/switch control module 60, a signal input end of the photocoupler control module 60 is connected with a signal output end of the MCU module 10, and a signal output end is connected with a signal input end of the current detection module 30.
One end of a resistor R18 of the photoelectric coupling control module 60 is connected with a PA8 pin of the MCU module 10, and a drain electrode of FT1 of the photoelectric coupling control module 60 is connected with a FILTREP pin of the current detection module 30.
Like this, through the setting of optoelectronic coupling control module 60, MCU module 10 controls through optoelectronic coupling control module 60 and measures the electric current of load, owing to do not have direct and load to be connected, so both the coupling has transmitted the signal, has played the effect of keeping apart the interference again.
As shown in fig. 8, further, the dc current meter for detecting a ground fault of the dc system based on the power grid further includes a lamp control module 70, where the lamp control module 70 includes a lighting unit 71 and an indicator light unit 72, and signal input ends of the lighting unit 71 and the indicator light unit 72 are respectively connected to a signal output end of the MCU module 10.
One ends of resistors R33, R34, R35 and R29 of the indicator light unit 72 are respectively connected with pins PA15, PB3, PB4 and PB5 of the MCU module 10; one end of the resistor R29 of the lighting unit 71 is connected to the pin PB5 of the MCU module 10, respectively.
Therefore, when the ammeter is used in a dark environment, the illuminating unit 71 can play a good illuminating role, so that the cable plate or the terminal strip can be quickly checked, and convenience is provided for current detection; when the load is overloaded, the red lamp of the indicator lamp unit 72 is on, the green lamp is on in a normal state, and the blue lamp is on when the main control chip of the circuit board is overheated, so that a good warning effect can be achieved.
Further, in order to make the applicability of the dc ammeter wider, the power module 50 further includes a power switch unit 56 for turning on and off the circuit.
The signal input terminal of the selection switch unit 56 is connected to the pin IN + of the first voltage stabilizing unit 53, and the output terminal is connected to the EN pin of the first voltage stabilizing unit 53.
Thus, the charging unit 52 is connected to the external battery through the pin BAT. When power is supplied by the USB power source, the external battery can be charged, and whether power is supplied to the ammeter is controlled by turning on and off the switch unit 56. When the external connection can not be supplied with power by the USB power supply, the external battery is controlled to supply power by the on and off of the switch unit 56, so that the direct current ammeter can be used in the power supply environment without a fixed power supply, and the application range of the direct current ammeter is wider.
Further, the chip model of the MCU module 10 is STM32F030K6T 6.
Further, the chip model of the second voltage regulation unit 54 is LD1117 ASTR.
Further, the chip model of the analog-to-digital conversion module 20 is ADC 1118.
Further, the chip model of the charging unit 52 is TP 4056.
TP4056 is a complete single-section lithium ion battery linear charger adopting constant current/constant voltage. The SOP8 package with heat sink at the bottom and the small number of external components make TP4056 a desirable choice for portable applications. The TP4056 may be adapted to operate with USB power supplies and adapter power supplies.
Because an internal PMOSFET architecture is adopted and a reverse charging prevention circuit is added, an external isolation diode is not needed. The thermal feedback allows for automatic adjustment of the charging current to limit the chip temperature under high power operation or high ambient temperature conditions. The charging voltage is fixed at 4.2V and the charging current can be set externally by a resistor. TP4056 will automatically terminate the charging cycle when the charging current drops to set point 1/10 after the final float voltage is reached.
When the input voltage (ac adapter or USB power supply) is removed, TP4056 automatically enters a low current state, reducing the battery leakage current to below 2 uA. TP4056 may also be placed in a shutdown mode when power is available to reduce the supply current to 55 uA. Other features of the TP4056 include battery temperature detection, under-voltage lockout, automatic recharging, and two LED status pins to indicate charging, and termination.
As shown in fig. 9, further, the dc current meter for detecting a ground fault of the dc system based on the power grid further includes a membrane key 80, and a signal output end of the membrane key 80 is connected to a signal input end of the MCU module 10.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (9)
1. The utility model provides a direct current ampere meter based on electric wire netting detects direct current system ground fault which characterized in that: the current detection device comprises an MCU module, an analog-to-digital conversion module, a current detection module, a display module and a power module, wherein the signal output end of the MCU module is respectively connected with the signal input ends of the current detection module and the display module, the signal output end of the analog-to-digital conversion module is connected with the signal input end of the MCU module, the signal output end of the current detection module is connected with the signal input end of the analog-to-digital conversion module, and the power module respectively provides electric energy for the MCU module, the analog-to-digital conversion module, the current detection module and the display module.
2. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 1, wherein: the power module comprises a power supply unit, a charging unit, a first voltage stabilizing unit, a second voltage stabilizing unit and an isolation power supply, wherein the signal output end of the power supply unit is connected with the signal input end of the charging unit, the signal output end of the charging unit is connected with the signal input end of the first voltage stabilizing unit, and the signal output end of the first voltage stabilizing unit is respectively connected with the signal input ends of the second voltage stabilizing unit and the isolation power supply.
3. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 1, wherein: the direct current ammeter for detecting the ground fault of the direct current system based on the power grid further comprises a photoelectric coupling control module, wherein a signal input end of the photoelectric coupling control module is connected with a signal output end of the MCU module, and a signal output end of the photoelectric coupling control module is connected with a signal input end of the current detection module.
4. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 1, wherein: the direct current ammeter for detecting the ground fault of the direct current system based on the power grid further comprises a lamp control module, the lamp control module comprises a lighting unit and an indicator light unit, and the signal input ends of the lighting unit and the indicator light unit are respectively connected with the signal output end of the MCU module.
5. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 2, wherein: the power supply module also comprises a power supply switch unit for opening and closing the circuit.
6. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 1, wherein: the chip model of the MCU module is STM32F030K6T 6.
7. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 2, wherein: the chip model of the second voltage stabilizing unit is LD1117 ASTR.
8. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 1, wherein: the analog-to-digital conversion module has a chip model of an ADC 1118.
9. The direct current ammeter for detecting the direct current system ground fault based on the power grid as claimed in claim 2, wherein: the chip model of the charging unit is TP 4056.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911047839.XA CN110618311A (en) | 2019-10-30 | 2019-10-30 | Direct current ammeter based on electric wire netting detects direct current system ground fault |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911047839.XA CN110618311A (en) | 2019-10-30 | 2019-10-30 | Direct current ammeter based on electric wire netting detects direct current system ground fault |
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| CN110618311A true CN110618311A (en) | 2019-12-27 |
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| CN201911047839.XA Pending CN110618311A (en) | 2019-10-30 | 2019-10-30 | Direct current ammeter based on electric wire netting detects direct current system ground fault |
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| CN208076601U (en) * | 2018-03-28 | 2018-11-09 | 杭州超耐德科技有限公司 | A kind of zero-sequence current table |
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| CN210954163U (en) * | 2019-10-30 | 2020-07-07 | 广东省高级技工学校 | Direct current ammeter based on electric wire netting detects direct current system ground fault |
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2019
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203232121U (en) * | 2013-03-11 | 2013-10-09 | 李社勇 | Secondary neutral point multipoint grounding monitoring device for voltage transformer of transformer substation |
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