CN204241571U - A kind of hyperchannel grounded screen branch impedance measurement mechanism based on radio communication - Google Patents
A kind of hyperchannel grounded screen branch impedance measurement mechanism based on radio communication Download PDFInfo
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- CN204241571U CN204241571U CN201420806739.7U CN201420806739U CN204241571U CN 204241571 U CN204241571 U CN 204241571U CN 201420806739 U CN201420806739 U CN 201420806739U CN 204241571 U CN204241571 U CN 204241571U
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Abstract
The utility model discloses a kind of hyperchannel grounded screen branch impedance measurement mechanism based on radio communication.The output channel of current excitation current source mostly is single channel, and in measuring process, continuous manual line changes the position that pulse current injectingt flows out node location and DATA REASONING node, measures loaded down with trivial details, easily anti-raw mistake.Of the present utility modelly be characterised in that, exciting current source module produces constant or AC signal under the control of micro controller module; Current switching module switches inflow and the outflow port of current signal under the control of micro controller module; The inflow of current switching module is connected with hyperchannel junction block with outflow port; Voltage switching module switches the input port of voltage signal under the control of micro controller module; The input port of voltage switching module is connected with hyperchannel junction block.The utility model can be grounded the measurement of net impedance, and Measurement channel is many, and automatization level is high simultaneously, reduces the workload of measurement.
Description
Technical field
The utility model relates to grounded screen branch impedance measurement mechanism, particularly a kind of hyperchannel grounded screen branch impedance measurement mechanism based on radio communication.
Background technology
Grounded screen is the important guarantee that substation safety runs, its ground connection performance is subject to the attention of production run department always, the standard of Grounding performance is that its integral ground resistance can not be above standard setting, therefore need regularly to measure the stake resistance of grounded screen, current power department regularly detects grounding net of transformer substation entirety.The be above standard reason of value of grounded screen overall electrical resistance is all that therefore the branch impedance of measurement grounded screen has great significance to electric system because indivedual branch impedance increases due to reasons such as corrosion.
Along with modern bulk power grid is to UHV (ultra-high voltage), Large Copacity and remote future development, to power system security, stable and economical operation requirement is more and more higher, run in order to ensure power system safety and stability and improve power supply reliability, just must ensure that earthing device has excellent performance.But the grounded screen be embedded in for a long time in soil is easily corroded, its main cause has: the first, and due to China's economic condition restriction, early stage most of transformer station all selects the steel more cheap than copper as grounded screen material.Show according to correlative study, faster than copper 3 ~ 4 times of the corrosion rate of common band steel in soil.Second, metal erosion is also relevant with factors such as weather conditions, soil resistivity, P in soil H value, soil saliferous water cut, soil oxygen level and microorganisms, China's area is wide, weather conditions are complicated, particularly environment in recent years is destroyed serious, acid rain has even been descended in some places, and this just accelerates the corrosion speed of grounded screen.3rd, unreasonable owing to designing, do not select suitable conductor material, do not take necessary anti-corrosion measure, the human factors such as failure welding, solder skip, rosin joint are also the major reasons causing grounding grids to corrode.Finally, As time goes on, conductor resistance constantly increases, and when having lightning current or dash current flows through grounded screen, grounding grids may be caused to rupture because of heating or large-current electric power.
Show according to domestic and international fact-finding organ in recent years, grounding grids annual corrosion rate in the soil that corrosivity is stronger can reach 2.0 millimeters; In the soil that corrosivity is strong, its annual corrosion rate can reach 3.4 millimeters; In the soil that corrosivity is extremely strong, within its year, corrosion rate even can reach 8.0 millimeters.China is investigated some local grounding net of transformer substation, during 1981 ~ 1985 years, Guangdong Province's electric power experiment al research institute the has run the more than ten years within the border transformer station of 130 35 kilovolts to 220 kilovolts to Guangdong Province excavates, found that and probably have the grounded screen in half transformer station to have corrosion phenomenon to a certain degree, in the middle of run eastern pier 110 kv substation of 16 years, the band steel grounded screen of its 12*4 specification has been corroded about 80%, has more seriously had ten many places fractures; Ping Fu hilllock 110 kv substation to have run 21 years, to be round steel diameter be its material that the grounded screen of 9 millimeters has been etched into slice.Therefore, corrosion can cause the increase of Resistance of Grounding Grids, and finally makes earthing device degradation.
Once earthing device degradation; probably cause the phenomenons such as such as grounded screen potential anomalies increase, step voltage and touch voltage rising, the partial potential difference of grounded screen own; just probably there is ground short circuit fault in electric system; this not only crisis can ensure the life security of operations staff; also secondary circuit superpotential may be caused; and cause secondary circuit some protection element and device damage; more seriously cause opertaing device malfunction or be failure to actuate; make fault spread, bring huge economy and property loss to society and country.
Mostly adopt existing laboratory equipment to grounded screen fault measuring now, the output channel of excitation current source mostly is single channel, measuring voltage data acquisition digital multimeter or digital oscilloscope.In whole measuring process, whether the contact of probe is good has a huge impact measurement result.In measuring process, continuous manual line changes the position that pulse current injectingt flows out node location and DATA REASONING node simultaneously, measures loaded down with trivial details, easily anti-raw mistake.
Utility model content
Technical problem to be solved in the utility model is the defect overcoming the existence of above-mentioned prior art, a kind of hyperchannel grounded screen branch impedance measurement mechanism based on radio communication is provided, its excitation current source and voltage measurement port are all hyperchannel, and outflow port and voltage data measurement port can be injected by programming Control stream, it is convenient to measure, little labor intensive, should not make a mistake simultaneously.
For achieving the above object, the technical solution adopted in the utility model is as follows: a kind of hyperchannel grounded screen branch impedance measurement mechanism based on radio communication, comprise micro controller module, exciting current source module, signal processing module, current switching module, voltage switching module, data memory module, data communication module, Independent keys module, LCD MODULE and hyperchannel junction block, it is characterized in that
Described micro controller module is responsible for the process of the control and measurement data of whole measurement mechanism; Exciting current source module produces constant or AC signal under the control of micro controller module; Current switching module switches inflow and the outflow port of current signal under the control of micro controller module; The inflow of current switching module is connected with hyperchannel junction block with outflow port; Voltage switching module switches the input port of voltage signal under the control of micro controller module; The input port of voltage switching module is connected with hyperchannel junction block;
Described signal processing module carries out signal filtering to voltage switching module output voltage signal under the control of micro controller module, signal amplifies and A/D conversion; Digital value corresponding for sampled voltage signal is delivered to micro controller module by signal processing module; The data of collection are stored into data memory module by micro controller module; Micro controller module is communicated with a host computer by data communication module; LCD MODULE is display measurement interface under micro controller module controls; Independent keys module communicates with micro controller module, allocating and measuring parameter, control survey process; Described hyperchannel junction block is connected by wire with the accessible node of grounded screen.
Further, in described micro controller module, microcontroller adopts single-chip microcomputer, ARM, programmable logic device FPGA or CPLD.
Further, described data communication module adopts RS232, RS485, USB, wireless communication module or SD card.
Further, described data memory module adopts the outer NOR FLASH of sheet or NAND FLASH memory.
Further, the data of collection are first stored into high-speed memory in microcontroller by described micro controller module, then are stored into data memory module.
Further, the constant signal of excitation current source module output current to be amplitude be 0-10A or frequency are 20-2000Hz, amplitude is the stable sinusoidal signal of 0-10A.
Further, the inflow of described current switching module and outflow port are first linked in sequence with the input port of voltage switching module, then are linked in sequence with hyperchannel junction block.
Further, described current switching module adopts relay as change-over switch.
Further, described voltage switching module adopts analog switch selector switch as change-over switch.
Further, described Independent keys module adopts I
2the button of C interface keyboard driver identification input.
The utility model can be grounded the Quick Measurement of net branch impedance, and Measurement channel is many, and automatization level is high simultaneously, reduces the workload of measurement; The impedance magnitude between any two Measurement channel of Measurement accuracy can be realized, for Fault Diagnosis for Grounding Grids provides reference data; Measurement data is stored into the data memory module in device simultaneously, ensures the safety of image data; Transfer data to host computer by data communication module, host computer calculates the resistance value of each branch road.
Accompanying drawing explanation
Fig. 1 is structured flowchart of the present utility model.
Fig. 2 is excitation current source module principle figure of the present utility model.
Embodiment
Below in conjunction with specification drawings and specific embodiments, the utility model is further described.
Be made up of micro controller module 1, exciting current source module 2, signal processing module 3, current switching module 4, voltage switching module 5, data memory module 6, data communication module 7, Independent keys module 8, LCD MODULE 10 and hyperchannel junction block 9 see the measurement mechanism in accompanying drawing 1, figure.
Micro controller module 1 is responsible for the process of the control and measurement data of whole measurement mechanism; Exciting current source module 2 produces constant or AC signal under the control of micro controller module 1; Current switching module 4 switches inflow and the outflow port of current signal under the control of micro controller module 1; The inflow of current switching module 4 is connected with hyperchannel junction block 9 with outflow port; Voltage switching module 5 switches the input port of voltage signal under the control of micro controller module 1; The input port of voltage switching module 5 is connected with hyperchannel junction block 9; Signal processing module 3 carries out signal filtering to voltage switching module 5 output voltage signal under the control of micro controller module 1, signal amplifies, A/D conversion; Digital value corresponding for sampled voltage signal is delivered to micro controller module 1 by signal processing module 3; The data of collection are stored into data memory module 6 by micro controller module 1; Micro controller module 1 is communicated with host computer 11 by data communication module 7; LCD MODULE 10 is display measurement interface under micro controller module 1 controls; Independent keys module 8 communicates with micro controller module 1, allocating and measuring parameter, control survey process; Hyperchannel junction block 9 is connected by wire with the accessible node of grounded screen.
In micro controller module 1, microcontroller adopts single-chip microcomputer, ARM, programmable logic device FPGA or CPLD.Data communication module 7 adopts RS232, RS485, USB, wireless communication module or SD card.Data memory module 6 adopts outer NOR FLASH, NAND FLASH memory of sheet.The data of collection are first stored into high-speed memory in microcontroller by micro controller module 1, then are stored into data memory module 6.The stable sinusoidal signal that constant signal or the frequency of exciting current source module 2 output current to be amplitude be 0-10A are 20-2000Hz, amplitude is 0-10A.The inflow of current switching module 4 and outflow port are first linked in sequence with the input port of voltage switching module 5, then are linked in sequence with hyperchannel junction block 9.Current switching module 4 adopts relay as change-over switch.Voltage switching module 5 adopts analog switch selector switch as change-over switch.Independent keys module 8 adopts I
2the button of C interface keyboard driver identification input.
In the present embodiment, micro controller module 1 adopts the 32 bit processor STM32F103ZE with ARM Cortex-M3 kernel, has abundant Peripheral Interface, convenient and other module communications.
The physical circuit figure of exciting current source module 2 is represented see accompanying drawing 2.In the present embodiment, exciting current source module 2 utilizes a high input impedance, the operational amplifier of high gain amplifier forms a positive-feedback circuit, is indirectly carried on power resistor by the controllable voltage that D/A converter exports.In circuit, MCP6402 is the operational amplifier of a single-ended power, quiescent current 45uA, gain wide-band 1MHz, input impedance 1013 ohm.TIP121 is the Darlington thyristor of a NPN type, can bear maximum shutoff voltage 80V, maximum continuous current 5A, peak power 65W.
In the present embodiment, signal processing module 3 adopts 24 A/D converter ADS1241.Inside carries programmable amplifier and FIR (Finite Impulse Response) wave filter, and gain margin is 1-128 times, the undesired signal of 50Hz and 60Hz of filtering simultaneously.ADS1241 image data can be communicated in 8 bit data modes with microprocessor by spi bus.
In the present embodiment, voltage switching module 5 is selected with two 16 tunnels analogy switches as passage bridge switch, and ADG1206 selected by analog switch.It has the binary address end A0 ~ A4 of an Enable Pin and 4, have that conduction impedance is low, leakage current is little, the response time is short, power supply voltage range is wide, low in energy consumption, encapsulate the advantages such as little.
In the present embodiment, current switching module 4 selects the G6K-2F-Y relay of Omron Corp as selector switch.It is two-way single-pole double-throw switch (SPDT), its rated operational voltage 4.5V, rated operational current 23.2mA, switch contact impedance 100m Ω, and the switching manipulation time is maximum is no more than 3ms.
In the present embodiment, the Measurement channel of grounded screen fault measurement mechanism is 16 passages.
Claims (10)
1. the hyperchannel grounded screen branch impedance measurement mechanism based on radio communication, comprise micro controller module (1), exciting current source module (2), signal processing module (3), current switching module (4), voltage switching module (5), data memory module (6), data communication module (7), Independent keys module (8), LCD MODULE (10) and hyperchannel junction block (9), it is characterized in that
Described micro controller module (1) is responsible for the process of the control and measurement data of whole measurement mechanism; Exciting current source module (2) produces constant or AC signal under the control of micro controller module (1); Current switching module (4) switches inflow and the outflow port of current signal under the control of micro controller module (1); The inflow of current switching module (4) is connected with hyperchannel junction block (9) with outflow port; Voltage switching module (5) switches the input port of voltage signal under the control of micro controller module (1); The input port of voltage switching module (5) is connected with hyperchannel junction block (9);
Described signal processing module (3) carries out signal filtering to voltage switching module (5) output voltage signal under the control of micro controller module (1), signal amplifies and A/D conversion; Digital value corresponding for sampled voltage signal is delivered to micro controller module (1) by signal processing module (3); The data of collection are stored into data memory module (6) by micro controller module (1); Micro controller module (1) is communicated with a host computer (11) by data communication module (7); LCD MODULE (10) is display measurement interface under micro controller module (1) controls; Independent keys module (8) communicates with micro controller module (1), allocating and measuring parameter, control survey process; Described hyperchannel junction block (9) is connected by wire with the accessible node of grounded screen.
2. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 1, it is characterized in that, in described micro controller module (1), microcontroller adopts single-chip microcomputer, ARM, programmable logic device FPGA or CPLD.
3. hyperchannel grounded screen branch impedance measurement mechanism according to claim 1, is characterized in that, described data communication module (7) adopts RS232, RS485, USB, wireless communication module or SD card.
4. hyperchannel grounded screen branch impedance measurement mechanism according to claim 1, is characterized in that, described data memory module (6) adopts the outer NOR FLASH of sheet or NAND FLASH memory.
5. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 4, it is characterized in that, the data of collection are first stored into high-speed memory in microcontroller by described micro controller module (1), then are stored into data memory module (6).
6. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 1, it is characterized in that, constant signal or the frequency of exciting current source module (2) output current to be amplitude be 0-10A be 20-2000Hz, stable sinusoidal signal that amplitude is 0-10A.
7. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 1, it is characterized in that, the inflow of described current switching module (4) and outflow port are first linked in sequence with the input port of voltage switching module (5), then are linked in sequence with hyperchannel junction block (9).
8. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 1, it is characterized in that, described current switching module (4) adopts relay as change-over switch.
9. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 1, it is characterized in that, described voltage switching module (5) adopts analog switch selector switch as change-over switch.
10. according to the hyperchannel grounded screen branch impedance measurement mechanism described in claim 1, it is characterized in that, described Independent keys module (8) adopts I
2the button of C interface keyboard driver identification input.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104655983A (en) * | 2014-12-17 | 2015-05-27 | 国家电网公司 | Multi-channel grounding grid fault measuring device and method based on wireless communication |
| CN105785135A (en) * | 2016-04-11 | 2016-07-20 | 国网安徽省电力公司电力科学研究院 | Frequency conversion ground impedometer |
| CN109580722A (en) * | 2018-12-25 | 2019-04-05 | 国网陕西省电力公司电力科学研究院 | A kind of ground net corrosion monitoring method and device based on AC admittance method |
| CN110082633A (en) * | 2019-04-23 | 2019-08-02 | 史磊 | A kind of grounding net of transformer substation on-line monitoring system and method |
-
2014
- 2014-12-17 CN CN201420806739.7U patent/CN204241571U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104655983A (en) * | 2014-12-17 | 2015-05-27 | 国家电网公司 | Multi-channel grounding grid fault measuring device and method based on wireless communication |
| CN105785135A (en) * | 2016-04-11 | 2016-07-20 | 国网安徽省电力公司电力科学研究院 | Frequency conversion ground impedometer |
| CN109580722A (en) * | 2018-12-25 | 2019-04-05 | 国网陕西省电力公司电力科学研究院 | A kind of ground net corrosion monitoring method and device based on AC admittance method |
| CN109580722B (en) * | 2018-12-25 | 2021-07-06 | 国网陕西省电力公司电力科学研究院 | Grounding grid corrosion monitoring method and device based on alternating current admittance method |
| CN110082633A (en) * | 2019-04-23 | 2019-08-02 | 史磊 | A kind of grounding net of transformer substation on-line monitoring system and method |
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