CN102707167B - State monitoring system for grounding grid based on industrial personal computer - Google Patents
State monitoring system for grounding grid based on industrial personal computer Download PDFInfo
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Abstract
The invention discloses a state monitoring system for a grounding grid based on an industrial personal computer. The state monitoring system comprises a ground impedance tester which is used for receiving a test command from a central processor and measuring the power frequency alternating-current parameters of the grounding grid, a direct-current on-resistance tester which is used for receiving a test command from the central processor and measuring the direct-current on-resistance among grounding wires, and the central processor which is used for sending test commands to the ground impedance tester and the direct-current on-resistance tester based on the development of the industrial personal computer, statistically analyzing the measured power frequency alternating-current parameters and the direct-current on-resistance in time and location and evaluating the operating condition of the grounding grid. Based on a grounding grid intelligent measurement system developed by the industrial personal computer, the state monitoring system for the grounding grid based on the industrial personal computer, disclosed by the invention, can test the electrical parameters of the grounding grid in standardization and intellectualization manner, and can collect and analyze the electrical parameters and evaluate the operating condition, so as to effectively reduce errors generated during the measurement and improve the efficiency for the field test.
Description
Technical field
The present invention relates to electric system grounded screen safe operation field, more specifically, relate to the Receive Ground Mat State Monitoring System based on industrial computer.
Background technology
Grounded screen is one of important measures ensureing power system security reliability service.When overcurrent appears in electric system, good ground connection can make electric current spill in the earth fast, ensures the safety of power equipment and staff.But grounded screen is embedded in underground for a long time, by the impact of earth current, easily there is soil electrochemistry corrosion, break down or rupture, affecting its diffusing ability, harm power system security.Therefore, the running status of monitoring grounding net is most important.
Disclose a kind of grounded screen wireless detection device in Chinese utility model patent instructions CN201035712, radio magnetic wave can be utilized to be grounded the measurement of impedance; Disclose a kind of Anomalous frequency test system for ground resistance of grounded screen in Chinese utility model patent instructions CN201229381, realized the facilitation operation of test by single-chip microcomputer and touch-screen.
The above-mentioned method and apparatus for grounded screen measurement of electric parameter, in measuring process, all needs the manual record test data of tester, and finishing analysis, workload is huge, is difficult to validity and the standardization of guaranteeing test data; And be accustomed to difference because different testers records, detecting information incomplete recording may cause occurring error to test result analysis, reduces the reliability of test.
Summary of the invention
The object of the present invention is to provide a kind of Receive Ground Mat State Monitoring System based on industrial computer, the measurement of the earth mat electric parameter that can full automaticly achieve a butt joint, and state analysis and assessment.
Based on the Receive Ground Mat State Monitoring System of industrial computer, comprising:
Earth loop impedance test instrument, is connected with center processor, and for the test command of receiving center processor, the voltage and current signal of measurement & characterization grounded screen industrial frequency AC parameter is also fed back to center processor;
Direct current continuity test instrument, is connected with center processor, and for the test command of receiving center processor, the voltage and current signal of the direct current conducting resistance between measurement & characterization down conductor is also fed back to center processor;
Center processor, develop based on industrial computer, for sending test command to earth loop impedance test instrument and direct current continuity test instrument, receive the voltage and current signal of earth loop impedance test instrument and direct current continuity test instrument feedback, industrial frequency AC parameter and direct current conducting resistance is calculated according to voltage and current signal, and time and geographic statistical study are carried out to industrial frequency AC parameter and direct current conducting resistance, and comprehensive assessment is carried out to the running status of grounded screen.
Further, described center processor comprises information acquisition and administration module, data analysis module, state estimation module and information derive module;
Information acquisition and administration module, test condition is set for user, corresponding test command is sent to earth loop impedance test instrument and direct current continuity test instrument according to test condition, receive electric current and the voltage signal of two tester feedbacks, each electric parameter and industrial frequency AC parameter and direct current conducting resistance is calculated according to electric current and voltage signal, by each electric parameter and corresponding test condition association store, and do bookkeeping for user;
Data analysis module, electric parameter for storing data analysis module carries out time and geographic statistical study, so that user grasps the geographic distribution statistical information of the every electric parameter of grounded screen trend and test point corresponding to electric parameter over time;
State estimation module, carries out comprehensive assessment for the electric parameter stored according to data analysis module to grounded screen running status;
Information derives module, optionally reads electric parameter, data results and condition evaluation results, and generate test report or/and form for imposing a condition according to user from information acquisition and administration module, data analysis module and state estimation module.
Further, described earth loop impedance test instrument comprises alien frequencies constant-current supply, current sensor, voltage sensor, Current amplifier and filtering circuit, voltage amplification and filtering circuit, an A/D transducer, DSP, the first serial communication interface; Current sensor connects Current amplifier and filtering circuit, voltage sensor connects voltage amplification and filtering circuit, Current amplifier is connected an A/D transducer with filtering circuit and voltage amplification respectively with filtering circuit, one A/D transducer connects DSP, DSP connects center processor by the first serial communication interface, and DSP also connects alien frequencies constant-current supply.
Further, described continuity test circuit comprises DC constant flowing power, current sampling circuit, current amplifier, voltage sampling circuit, voltage amplifier, the 2nd A/D transducer, microprocessor, the second serial communication interface; Current sampling circuit connects the 2nd A/D transducer by current amplifier, and voltage sampling circuit connects the 2nd A/D transducer by voltage amplifier, and the 2nd A/D transducer connects microprocessor, and microprocessor connects industrial computer by the second serial communication interface.
The present invention compared to existing technology tool has the following advantages:
1) standardization, the intelligent test of grounded screen electric parameter can be completed based on the grounded screen intelligent measuring systems of industrial computer platform development; Autostore test data, and carry out finishing analysis, test result is shown with patterned form, more visual and clear; Effectively can reduce the mistake in measuring process, improve the efficiency of field experiment.Meanwhile, to the standardization Acquire and process of detecting information, perfect production management, serves positive effect to the management of earth mat and monitoring.
2) can according to the parameter measuring gained, the running status current to grounded screen carries out intelligentized objective, comprehensive, scientifical, comprehensive evaluation, and provides the comments with actual directive significance.
Accompanying drawing explanation
Fig. 1 is overall technological scheme figure of the present invention.
Fig. 2 is the circuit block diagram of earth loop impedance test instrument in the present invention.
Fig. 3 is the circuit block diagram of continuity test instrument in the present invention.
Fig. 4 is the schematic diagram of embodiment graphical data display.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further details:
As shown in Figure 1, the Receive Ground Mat State Monitoring System based on industrial computer comprises center processor, earth loop impedance test instrument and direct current continuity test instrument.Center processor is developed based on industrial computer, test command is sent to earth loop impedance test instrument and direct current continuity test instrument, earth loop impedance test instrument and direct current continuity test instrument are tested the direct current conducting resistance between the industrial frequency AC parameter of grounded screen and down conductor respectively and feed back to center processor, and center processor carries out statistical study to the data that two testers feed back and assesses the running status of grounded screen.
Earth loop impedance test instrument is grounded the measurement of the industrial frequency AC parameters such as impedance, soil resistivity, step voltage, touch voltage, place surface potential distribution.As shown in Figure 2, earth loop impedance test instrument comprises alien frequencies constant-current supply, current sensor, voltage sensor, Current amplifier and filtering circuit, voltage amplification and filtering circuit, A/D transducer, DSP, serial communication interface.Current sensor connects Current amplifier and filtering circuit, voltage sensor connects voltage amplification and filtering circuit, Current amplifier is connected A/D transducer with filtering circuit and voltage amplification respectively with filtering circuit, A/D transducer connects DSP, DSP connects industrial computer by serial communication interface, and DSP also connects alien frequencies constant-current supply.DSP receives the test command of industrial computer by serial communication interface, controls according to test command the measuring current that alien frequencies constant-current supply exports corresponding size and frequency.Alien frequencies constant-current supply is an interchange constant-current supply, and output waveform is sinusoidal wave, and output frequency can be set as 45Hz and 55Hz by dsp chip; Output current is also controlled by dsp chip, maximumly reaches 3A; Export and export external measuring circuit to, for external loop provides power supply by C1-AC and C2-AC two terminals after isolation.Alien frequencies constant-current supply adopts ripe SPWM switch power technology, and to reach, output waveform distortion is little, the advantage of small in volume.The current sensor of C1-AC and C2-AC end and Current Mutual Inductance coil gather the current signal in external measuring circuit, remove through Current amplifier and filtering circuit and on-the-spot disturb that (centre frequency is 45Hz or 55Hz, have employed high precision and high stability electronic component, so centre frequency has very high precision, there is very high Q value simultaneously) and after amplifying, enter AD converter (at a high speed 12 modulus conversion chips).Use the voltage signal of the voltage sensor of P1-AC and P2-AC (can sampling resistor be adopted) collecting test point simultaneously, after amplification, filtering circuit, enter AD converter.AD converter to dsp chip, and sends by real time communication through COMs the information feed back that gathers to industrial computer.
Direct current continuity test instrument is for measuring the direct current conducting resistance between down conductor.As shown in Figure 3, continuity test circuit comprises DC constant flowing power, current sampling circuit, current amplifier, voltage sampling circuit, voltage amplifier, A/D transducer, microprocessor, serial communication interface.Current sampling circuit connects A/D transducer by current amplifier, and voltage sampling circuit connects A/D transducer by voltage amplifier, and A/D transducer connects microprocessor, and microprocessor connects industrial computer by serial communication interface; Microprocessor also can connect peripheral hardware, such as display screen, keyboard etc.Microprocessor receives the test command of industrial computer by serial communication interface, controls according to test command the measuring current that DC constant flowing power exports corresponding size.DC constant flowing power provides the D.C. high-current needed for test according to user's request, maximumly reaches 10A.Electric current exports external measuring circuit to by C1-DC and C2-DC two terminals after isolation, connects measuring resistance sampled current signals with P1-DC and P2-DC two terminals.The electric current that current sensor and voltage sensor gather and voltage signal, after corresponding amplifying circuit, enter A/D converter, finally enter microprocessor.Microprocessor can directly process data, also data can be delivered in industrial computer by real time communication through COMs and carry out unifying process.
Center processor is based on industrial computer platform development, realizes graphical, the facilitation of information acquisition, the intellectuality of data management and analysis, for user offers convenience.Center processor comprises four large functional modules: information acquisition and administration module, data analysis module, state estimation module and information derive module.
Information acquisition and administration module are grounded management, the collection of net relevant information, adopt dialog box and tabular mode comprehensively to realize, make metrical information very clear while simple operation.Information acquisition and administration module set test condition for user and comprise the information such as measuring current size, test frequency, test point position, test environment (temperature, humidity, weather conditions), foundation test condition sends test command to the tester of bottom, and test command comprises measuring current size and/or test frequency information.Information acquisition and administration module receive electric current and the voltage signal of bottom two tester, various electric parameter is calculated according to electric current and voltage signal, by each electric parameter and corresponding test condition association store, and check for user, edit, the bookkeeping such as sequence.
Data analysis module electrically carries out time, geographic statistics, analysis, drawing to the parameter that information acquisition and administration module store, adopt flat distribution map and curve map display, be convenient to the geographic distribution statistical information that user grasps the every electric parameter of grounded screen trend and test point corresponding to electric parameter over time more easily.
State estimation module carries out comprehensive assessment according to detecting information to the diffusing ability of grounded screen running status and grounded screen, ducting capacity, structural intergrity and the degree etc. that is corroded, and provides valuable comments.Its core is grounded screen hierarchy algorithm.The impedance ground that this algorithm utilizes systematic survey to obtain, step voltage, touch voltage, conducting resistance quadrinomial parameter, in conjunction with the initial designs information of earth mat, according to fuzzy hierarchy Assessment theory, carry out the overall evaluation to the running status of earth mat.And according to evaluation result, in conjunction with the correlation experience of grounding net of transformer substation site test, provide the comments with actual directive significance.Concrete implementation can see " Zhang Penghe etc. adopt the grounded screen state evaluation studies of Fuzzy AHP, " electrical measurement and instrument " the 48th volume the 12nd phase in 2011 ".
Information derives module and imposes a condition according to user, optionally read electric parameter, data results and condition evaluation results automatically generate and export test report, testing journal sheet etc., make grounded screen detecting information can intelligent, normalized management, enhance productivity.Impose a condition for ease of user, the test report that can prestore in information derivation module and report form template are selected for user.
Embodiment:
For taking into account the needs of the communication of bottom test circuit and data management analysis, industrial computer selects PCM-LX main frame, 3.5 cun of embedded main boards, and AMD LX800 processor, meets RoHs standard, supports windows XP/CE/XPe system.Software, based on Winxp operating system, adopts .NETFramework 4.0 to develop.
When measuring grounded screen alternating electric parameter, lead-out terminal C1-AC, C2-AC, P1-AC, the P2-AC of the earth loop impedance test instrument in the present invention are connected on ground stud, test condition are set being loaded in the software systems on industrial computer, send test command; System can automatic collecting test data record detecting information.
The method measuring DC electrical parameter is similar to the above, only earth loop impedance test instrument need be changed into direct current continuity test instrument.
After having tested, the software in industrial computer has collected whole detecting informations.User can inquire about and edit whole data in data management module; Then as required, select specific data group to carry out adding up, the analysis such as drawing.Fig. 4 is the schematic diagram of this instance data graphic software platform.When assessing grounded screen running status, only need select test duration section, evaluation module understands automatic screening and the total data processed in this time period, runs assessment algorithm, carries out the comprehensive assessment of grounded screen running status, and export comments.Table 1 is the condition evaluation results of embodiment.
The condition evaluation results of table 1 embodiment
When user needs to generate test report and testing journal sheet, the information that directly enters derives module, and select corresponding template, click information derives.
Claims (3)
1., based on the Receive Ground Mat State Monitoring System of industrial computer, comprising:
Earth loop impedance test instrument, is connected with center processor, and for the test command of receiving center processor, the voltage and current signal of measurement & characterization grounded screen industrial frequency AC parameter is also fed back to center processor;
Direct current continuity test instrument, is connected with center processor, and for the test command of receiving center processor, the voltage and current signal of the direct current conducting resistance between measurement & characterization down conductor is also fed back to center processor;
Center processor, develop based on industrial computer, for sending test command to earth loop impedance test instrument and direct current continuity test instrument, receive the voltage and current signal of earth loop impedance test instrument and direct current continuity test instrument feedback, industrial frequency AC parameter and direct current conducting resistance is calculated according to voltage and current signal, and time and geographic statistical study are carried out to industrial frequency AC parameter and direct current conducting resistance, and comprehensive assessment is carried out to the running status of grounded screen;
Described center processor comprises information acquisition and administration module, data analysis module, state estimation module and information derive module;
Information acquisition and administration module, test condition is set for user, corresponding test command is sent to earth loop impedance test instrument and direct current continuity test instrument according to test condition, receive electric current and the voltage signal of two tester feedbacks, each electric parameter and industrial frequency AC parameter and direct current conducting resistance is calculated according to electric current and voltage signal, by each electric parameter and corresponding test condition association store, and do bookkeeping for user;
Data analysis module, electric parameter for storing data analysis module carries out time and geographic statistical study, so that user grasps the geographic distribution statistical information of the every electric parameter of grounded screen trend and test point corresponding to electric parameter over time;
State estimation module, carries out comprehensive assessment for the electric parameter stored according to data analysis module to grounded screen running status;
Information derives module, optionally reads electric parameter, data results and condition evaluation results, and generate test report or/and form for imposing a condition according to user from information acquisition and administration module, data analysis module and state estimation module.
2. the Receive Ground Mat State Monitoring System based on industrial computer according to claim 1, it is characterized in that, described earth loop impedance test instrument comprises alien frequencies constant-current supply, current sensor, voltage sensor, Current amplifier and filtering circuit, voltage amplification and filtering circuit, an A/D transducer, DSP, the first serial communication interface; Current sensor connects Current amplifier and filtering circuit, voltage sensor connects voltage amplification and filtering circuit, Current amplifier is connected an A/D transducer with filtering circuit and voltage amplification respectively with filtering circuit, one A/D transducer connects DSP, DSP connects center processor by the first serial communication interface, and DSP also connects alien frequencies constant-current supply.
3. the Receive Ground Mat State Monitoring System based on industrial computer according to claim 1, it is characterized in that, described continuity test circuit comprises DC constant flowing power, current sampling circuit, current amplifier, voltage sampling circuit, voltage amplifier, the 2nd A/D transducer, microprocessor, the second serial communication interface; Current sampling circuit connects the 2nd A/D transducer by current amplifier, and voltage sampling circuit connects the 2nd A/D transducer by voltage amplifier, and the 2nd A/D transducer connects microprocessor, and microprocessor connects industrial computer by the second serial communication interface.
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| CN104678246B (en) * | 2015-02-03 | 2017-10-27 | 国网上海市电力公司 | A kind of grounding net of transformer substation etch state appraisal procedure and its system |
| US9977066B2 (en) * | 2015-04-15 | 2018-05-22 | Cooper Technologies Company | Systems, methods, and devices for diagnosing integrity of electrical conductor-carrying systems |
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| CN105842576B (en) * | 2016-03-23 | 2018-06-15 | 国网山东省电力公司潍坊供电公司 | Earth-continuity remote-controlled test device |
| CN107290592A (en) * | 2017-07-04 | 2017-10-24 | 河南天通电力有限公司 | Grounded screen electric resistance on-line monitoring system |
| CN108711938A (en) * | 2018-06-06 | 2018-10-26 | 珠海金华辰机电科技有限公司 | A kind of intelligent monitor system of traction institute earth mat |
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| CN108931691A (en) * | 2018-09-05 | 2018-12-04 | 贵州南源电力科技股份有限公司 | A kind of grounded screen impedance short distance on-line monitoring system |
| CN110265906B (en) * | 2019-06-26 | 2021-08-13 | 国网上海市电力公司 | Transformer substation grounding grid state evaluation method and computer system |
| CN110736889A (en) * | 2019-10-28 | 2020-01-31 | 海风电气(江苏)有限公司 | underwater equipment electrical performance detection system and test method |
| CN112098730A (en) * | 2020-09-15 | 2020-12-18 | 广东电网有限责任公司 | Ground impedance measurement system and method |
| CN113687146B (en) * | 2021-08-13 | 2023-11-24 | 国网河北省电力有限公司检修分公司 | Grounding grid down lead testing device based on wireless transmission |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2514353Y (en) * | 2001-09-28 | 2002-10-02 | 国家电力公司华中公司技术中心 | Measurer for grounding resistance of grounded counterpoise |
| CN2849736Y (en) * | 2005-08-02 | 2006-12-20 | 高政 | System for detecting large grounding network of power plant and transformer substation |
| CN101246199A (en) * | 2007-02-14 | 2008-08-20 | 高政 | Method and device for wirelessly detecting grounded screen fault |
| CN201508392U (en) * | 2009-07-16 | 2010-06-16 | 福建省普华电子科技有限公司 | Frequency-conversion grounding resistance measuring instrument |
| CN102095999A (en) * | 2010-12-14 | 2011-06-15 | 重庆大学 | Measuring device for diagnosing connecting state of grounding network |
| CN202614865U (en) * | 2012-05-18 | 2012-12-19 | 华中科技大学 | Grounding grid state monitoring device based on industrial control computer |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102360058A (en) * | 2011-10-20 | 2012-02-22 | 湖南省电力公司科学研究院 | Method for discriminating operation fault of transmission line tower grounding network |
-
2012
- 2012-05-18 CN CN201210154829.8A patent/CN102707167B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2514353Y (en) * | 2001-09-28 | 2002-10-02 | 国家电力公司华中公司技术中心 | Measurer for grounding resistance of grounded counterpoise |
| CN2849736Y (en) * | 2005-08-02 | 2006-12-20 | 高政 | System for detecting large grounding network of power plant and transformer substation |
| CN101246199A (en) * | 2007-02-14 | 2008-08-20 | 高政 | Method and device for wirelessly detecting grounded screen fault |
| CN201508392U (en) * | 2009-07-16 | 2010-06-16 | 福建省普华电子科技有限公司 | Frequency-conversion grounding resistance measuring instrument |
| CN102095999A (en) * | 2010-12-14 | 2011-06-15 | 重庆大学 | Measuring device for diagnosing connecting state of grounding network |
| CN202614865U (en) * | 2012-05-18 | 2012-12-19 | 华中科技大学 | Grounding grid state monitoring device based on industrial control computer |
Non-Patent Citations (2)
| Title |
|---|
| 变电站接地网实时监测系统的开发与应用;王萍、刘浔、陈爱文、李清波;《电工技术》;20060331(第3期);第16页第2、6段和第17页图2 * |
| 大型厂、站接地网状态监测与故障诊断系统研究;陈雷;《工程科技Ⅱ辑》;20090215(第02期);第13-14页 * |
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