CN103235174A - Voltage online monitoring device for power system - Google Patents
Voltage online monitoring device for power system Download PDFInfo
- Publication number
- CN103235174A CN103235174A CN201310149093XA CN201310149093A CN103235174A CN 103235174 A CN103235174 A CN 103235174A CN 201310149093X A CN201310149093X A CN 201310149093XA CN 201310149093 A CN201310149093 A CN 201310149093A CN 103235174 A CN103235174 A CN 103235174A
- Authority
- CN
- China
- Prior art keywords
- voltage
- divider
- buffer area
- power system
- data
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Measurement Of Current Or Voltage (AREA)
Abstract
The invention discloses a voltage online monitoring device for a power system. A high-voltage capacitive voltage divider is connected with a bus-bar and operated in the grid to divide the voltage of the bus-bar for the first time, a low voltage arm signal is transmitted to a secondary resistance-capacitance divider through a first coaxial cable, the secondary resistance-capacitance divider carries out secondary voltage division on the low voltage arm signal, the voltage signal at the low voltage side is transmitted to a high-speed data acquisition card to be subjected to A/D conversion through a second coaxial cable, and then the obtained digital signal is transmitted to an industrial personal computer to be judged, stored and analyzed; the high-voltage capacitive voltage divider, the secondary resistance-capacitance divider, the high-speed data acquisition card and the industrial personal computer are respectively grounded. The voltage online monitoring device for the power system can reach the sampling rate per channel of 7.5 MS/s, can run in the grid for long time, is low in power consumption and convenient to maintain, can track and record various over-voltage and voltage dip waveforms in an online manner, has various analysis and waveform processing functions, and provides scientific basis for the safe and reliable running of the power system.
Description
Technical field
The present invention relates to electric system on-line monitoring field, specifically is a kind of power system voltage on-Line Monitor Device based on the PCI-1714UL high-speed data acquisition card, is used for monitoring, record and analyzes all kinds of electro-magnetic transient faults of electric system.
Background technology
Operating experience shows that in the 10kV electric system, all kinds of voltages comprise internal overvoltage and lightning surge, and accident rate is higher, and various superpotential duration, amplitude, waveform, generation reason and the effect of insulation also had nothing in common with each other.Although a large amount of overvoltage protections such as lightning arrester have been installed in practice; but when the superpotential accident appears in system; owing to there is not monitoring device; be difficult to determine that the reason of accident is because superpotential amplitude or steepness surpass the holding capacity of equipment; still the reduction of the dielectric level of equipment or protective device have problem; also be difficult to determine because the fault that Past Voltage within Power System causes, the still damage that causes owing to exterior overvoltage.
In addition, along with computing machine and all kinds of susceptibility load based on microprocessor extensively are applied the voltage dip paid more and more attention.In fact, because the frequent generation of short trouble and big dynamo-electric starting, voltage dip is the power quality problem that the power consumer to the power distribution network terminal has the greatest impact.In IEEE and IEC standard, voltage dip temporary range of decrease value commonly used and duration two indexs are estimated.
On-line monitoring technique is development in recent years emerging technology very rapidly, in electric system, be used widely, but the present domestic and international all kinds of voltage on-Line Monitor Device of developing, generally all can only monitor Past Voltage within Power System, perhaps monitoring sampling rate, not reach every passage 7.5MS/s so high, and the existing apparatus function singleness, incomplete.
Summary of the invention
The objective of the invention is to overcome the deficiency of above-mentioned existing voltage on-Line Monitor Device, a kind of power system voltage on-Line Monitor Device is provided, realize improving sampling rate, the fault that online detection simultaneously, record and all kinds of superpotential of analysis electric system, voltage dip and harmonic wave cause, and can carry out frequency analysis by timing acquiring system voltage signal.
The technical solution used in the present invention is: a kind of power system voltage on-Line Monitor Device, comprise high-voltage capacitive divider, the secondary RC divider, high-speed data acquisition card and industrial computer, high-voltage capacitive divider is connected hanging net operation on the bus, voltage on the bus is carried out the dividing potential drop first time, by first concentric cable low-voltage arm signal is transferred to the secondary RC divider, the secondary RC divider is carried out second divided voltage to the low-voltage arm signal, and by second concentric cable voltage signal of low-pressure side is sent into high-speed data acquisition card and carry out the A/D conversion, again the digital data transmission that obtains is judged to industrial computer, store and analyze; High-voltage capacitive divider, secondary RC divider, high-speed data acquisition card and industrial computer be ground connection respectively.
Described secondary RC divider comprises first resistance, second resistance, first electric capacity and second electric capacity, first resistance is connected with signal input part with second resistance series connection back, first electric capacity is in parallel with first resistance, second electric capacity is in parallel with second resistance, and the two ends of second electric capacity are connected with signal output part.
Described high-speed data acquisition card is the PCI-1714UL high-speed data acquisition card.
The monitoring method of described power system voltage on-Line Monitor Device may further comprise the steps:
(1) high-voltage capacitive divider is carried out the dividing potential drop first time with the voltage on the bus, by first concentric cable low-voltage arm signal is transferred to the secondary RC divider;
(2) the secondary RC divider is carried out second divided voltage to the low-voltage arm signal, and by second concentric cable voltage signal of low-pressure side is sent into high-speed data acquisition card and carry out the A/D conversion, and deposits data in buffer area;
(3) industrial computer reads data and base value comparison from buffer area, has judged whether superpotential, voltage dip or harmonic wave order, when superpotential, voltage dip or harmonic wave order, automatically the data in the buffer area is deposited in the specified folder;
(4) superpotential and the voltage dip data that will deposit in the specified folder of the data analysis unit in the industrial computer access, and it is carried out waveform show; Access the harmonic wave order in the specified folder, and it is carried out phase analysis and frequency analysis.
Buffer area in the described step (2) comprises first buffer area and second buffer area, when data deposit in, deposits first buffer area earlier in, begins to deposit in second buffer area after first buffer area is filled with again, simultaneously the data of first buffer area is called away; After second buffer area is filled with, deposit first buffer area again in, simultaneously the data of second buffer area are called away.
The present invention compared with prior art has following beneficial effect:
(1) multiple functional, can the on-line monitoring Past Voltage within Power System, lightning surge and system voltage fall temporarily, can also carry out frequency analysis by the timing acquiring system voltage; By three passages while image data of PCI-1714UL capture card, sampling rate reaches every passage 7.5MS/s, can selective dilution store data; After the data acquisition storage is finished, can carry out waveform and show, analyze and transmission and printing.
(2) hanging net operation for a long time, power attenuation is little, and is easy to maintenance, can all kinds of superpotential of online tracing record electrical network and voltage dip waveform, and have various analyses and waveform processing function, can provide scientific basis for security of system, reliability service.
(3) access the data of storing in the database by the industrial computer data analysis unit, can carry out waveform and show, the superpotential data are amplified, can observe superpotential wave head time, amplitude and duration; Access harmonic data and can carry out frequency analysis, higher harmonics arrives 50 times.
(4) high-voltage capacitive divider adopts the silicon rubber oversheath, compact conformation, be pure electric capacity original paper, dielectric loss and inductance value are all very little, secondary RC divider transient characterisitics are good, have enough wide amplitude range of adjustment and frequency range, quickly response speed, the high value and constant input impedance, possesses the stable dividing potential drop coefficient of low-and high-frequency compatibility.
Description of drawings
Fig. 1 is structural representation of the present invention.
Fig. 2 is the circuit diagram of secondary RC divider of the present invention.
Fig. 3 is general structure schematic diagram of the present invention.
Fig. 4 is data acquisition flow figure of the present invention.
Fig. 5 is data analysis process flow diagram of the present invention.
Embodiment
Be described further below in conjunction with the technical scheme of drawings and Examples to invention.
As shown in Figure 1, a kind of power system voltage on-Line Monitor Device, comprise high-voltage capacitive divider, the secondary RC divider, PCI-1714UL high-speed data acquisition card and industrial computer, high-voltage capacitive divider is connected hanging net operation on the bus, voltage on the bus is carried out the dividing potential drop first time, by first concentric cable low-voltage arm signal is transferred to the secondary RC divider, the secondary RC divider is carried out second divided voltage to the low-voltage arm signal, and by second concentric cable voltage signal of low-pressure side is sent into the PCI-1714UL high-speed data acquisition card and carry out the A/D conversion, again the digital data transmission that obtains is judged to industrial computer, store and analyze; High-voltage capacitive divider, secondary RC divider, PCI-1714UL high-speed data acquisition card and industrial computer be ground connection respectively.
High-voltage capacitive divider adopts the silicon rubber oversheath, and compact conformation is pure electric capacity original paper, and dielectric loss and inductance value are all very little, can ignore substantially.Low-voltage arm is a very crucial part that influences the high-voltage capacitive divider performance, is following coaxial arrangement in principle, and capacity cell can make current path be evenly distributed in each element, reduces the influence of inductance as far as possible.Based on the basic demand to high-voltage capacitive divider, the high-pressure side of high-voltage capacitive divider and the dielectric between neutral terminal can bear industrial frequency AC and the DC voltage of certain amplitude.The technical parameter of the high-voltage capacitive divider that the present invention adopts is: the specified phase voltage of capacitor: 10/kV; Maximum working voltage: 12kV; The specified intrinsic standoff ratio 405:1 of voltage divider.The low-voltage arm rated capacity is 0.816; High-voltage arm electric capacity is: 2020.
As shown in Figure 2, the secondary RC divider comprises first resistance R
1, second resistance R
2, first capacitor C
1With second capacitor C
2, first resistance R
1With second resistance R
2Series connection back and signal input part U
InConnect first capacitor C
1With first resistance R
1Parallel connection, second capacitor C
2With second resistance R
2Parallel connection, second capacitor C
2Two ends and signal output part U
OutConnect.
Secondary RC divider intrinsic standoff ratio is 44:1, first capacitor C
1With first resistance R
1Be respectively 500pF and 220k Ω, second capacitor C
2With second resistance R
2Be respectively 22nF and 5k Ω.Secondary RC divider transient characterisitics are good, and wide amplitude range of adjustment and frequency range are arranged enough, and response speed, possesses the stable dividing potential drop coefficient of low-and high-frequency compatibility at high the value and constant input impedance faster.Secondary RC divider of the present invention meets the following conditions, and is undistorted in the time of can guaranteeing the circulation of power frequency and high-frequency signal:
Initial time U
Out(0
+)=C
l/ (C
1+ C
2) U
In(0
+)
Stable state is U constantly
Out(∞)==U
In(∞)
Initial time and stable state intrinsic standoff ratio constantly is equal, then:
C
l/(C
1+C
2)=R
2/(R
1+R
2)
That is: R
lC
l=R
2C
2
In the formula, U
OutRepresent output end voltage, U
InRepresent input terminal voltage, R
1Represent the resistance of first resistance, R
2Represent the resistance of second resistance, C
1Represent the electric capacity of first electric capacity, C
2Represent the electric capacity of second electric capacity.When parameter is chosen as C
1=500pF, C
2=22nF, R
1=220k Ω, R
2=5k Ω, can satisfy the lightning surge Testing requirement at this dividing potential drop current-responsive time.
As shown in Figure 3, high-voltage capacitive divider is carried out the dividing potential drop first time with the voltage on the bus, by first concentric cable low-voltage arm signal is transferred to the secondary RC divider; The secondary RC divider is carried out second divided voltage to the low-voltage arm signal, the primary voltage signal is through after twice dividing potential drop, drop to the scope that the PCI-1714UL high-speed data acquisition card can be gathered, in the dividing potential drop process, adopt high-voltage capacitive divider and secondary RC divider to keep waveform and steepness constant as far as possible, only reduce amplitude.Data are carried out the A/D conversion after entering the PCI-1714UL high-speed data acquisition card, judged, store and analyzed by corresponding proprietary software program again.
As shown in Figure 4, after data entered PCI-1714UL high-speed data acquisition card A/D conversion, thread 1 continuous image data also deposited buffer memory in.Because the data sampling frequency is higher, in order to satisfy the needs of high speed data transfer, avoids loss of data simultaneously, the FIFO(First Input First Output that the PCI-1714UL high-speed data acquisition card provides plate to carry each passage 8k) and the DMA data-transmission mode.Among the present invention, every channel sample rate is 32 7.5MHz, and the per second data volume is 720Mbps, and the speed of pci bus is 33MHz, and highway width 32bit, its peak transfer rate are 1056Mbps, and the clock zone difference must use FIFO to cushion.FIFO is divided into the two parts of reaching the standard grade, and equal and opposite in direction is called first buffer area and second buffer area.Earlier begin to write data from first buffer area, write full first buffer area after, beginning is write data to second buffer area.In this time, routine call function DRV_CheckEvent inquires about the state of FIFO, and in time call function DRV_FAITranster takes the data of first buffer area away then.Second buffer area is write when full, begins again to write data to first buffer area top, and at this moment, routine call function DRV_CheckEvent inquires about the state of FIFO, and in time call function DRV_FAITranster takes the data of second buffer area away then.So circulation.When the voltage magnitude of collection surpassed the base value of setting in the thread 2, thread 2 judged that superpotential is arranged, and extracts the superpotential data, and deposited with the form of " superpotential _ time .dat ".When data enter thread 3, adopt the monobasic multipoint method to judge whether to occur voltage dip, as voltage dip, extract the voltage dip data, and deposit with the form of " voltage dip _ time .dat ".For fear of the influence of disturbing, get 4 result of calculations in apparatus of the present invention as criterion, if continuous 4 times all show voltage dip, can voltage dip take place the judgement system so, start the record ripple.When needs carried out frequency analysis to system voltage, by the software setting, the voltage data in 20 cycles of timing acquiring system carried out frequency analysis.
The high sampling rate of PCI-1714UL high-speed data acquisition card is every passage 7.5MS/s, totally four passages.The present invention only uses wherein three passages, and designs and develops by software, makes this device data acquiring frequency adjustable, the highlyest is set to every passage 7.5MHz/s.When the voltage accident occurring, automatically in preceding 2 cycles of storage voltage accident, the accident 150 and the data in 18 cycles afterwards.The data in 18 cycles dilution storage is 100Ks/s after preceding 2 cycles of accident and the accident.
As shown in Figure 5, after data acquisition program deposits casualty data and harmonic data in database, can call data by data analysis software and carry out waveform demonstration, frequency analysis and phase analysis.For superpotential and voltage dip data, call in after the data analysis software, can carry out waveform to it and show, and mark it and exceed voltage magnitude most, multiple.HFS can locally amplify, and checks and analyzes the wave head duration.For harmonic data, call in after the data analysis software, can carry out phase analysis, frequency analysis, higher harmonics number of times reaches 50 times.
Claims (5)
1. power system voltage on-Line Monitor Device, it is characterized in that, comprise high-voltage capacitive divider, the secondary RC divider, high-speed data acquisition card and industrial computer, high-voltage capacitive divider is connected hanging net operation on the bus, voltage on the bus is carried out the dividing potential drop first time, by first concentric cable low-voltage arm signal is transferred to the secondary RC divider, the secondary RC divider is carried out second divided voltage to the low-voltage arm signal, and by second concentric cable voltage signal of low-pressure side is sent into high-speed data acquisition card and carry out the A/D conversion, again the digital data transmission that obtains is judged to industrial computer, store and analyze; High-voltage capacitive divider, secondary RC divider, high-speed data acquisition card and industrial computer be ground connection respectively.
2. power system voltage on-Line Monitor Device according to claim 1, it is characterized in that, described secondary RC divider comprises first resistance, second resistance, first electric capacity and second electric capacity, first resistance is connected with signal input part with second resistance series connection back, first electric capacity is in parallel with first resistance, second electric capacity is in parallel with second resistance, and the two ends of second electric capacity are connected with signal output part.
3. power system voltage on-Line Monitor Device according to claim 2 is characterized in that, described high-speed data acquisition card is the PCI-1714UL high-speed data acquisition card.
4. a monitoring method that is applicable to each described power system voltage on-Line Monitor Device among the claim 1-3 is characterized in that, may further comprise the steps:
(1) high-voltage capacitive divider is carried out the dividing potential drop first time with the voltage on the bus, by first concentric cable low-voltage arm signal is transferred to the secondary RC divider;
(2) the secondary RC divider is carried out second divided voltage to the low-voltage arm signal, and by second concentric cable voltage signal of low-pressure side is sent into high-speed data acquisition card and carry out the A/D conversion, and deposits data in buffer area;
(3) industrial computer reads data and base value comparison from buffer area, has judged whether superpotential, voltage dip or harmonic wave order, when superpotential, voltage dip or harmonic wave order, automatically the data in the buffer area is deposited in the specified folder;
(4) data analysis unit in the industrial computer accesses superpotential and the voltage dip data that deposit in the specified folder, and it is carried out the waveform demonstration; Access the harmonic wave order in the specified folder, and it is carried out phase analysis and frequency analysis.
5. according to the monitoring method of the power system voltage on-Line Monitor Device described in the claim 4, it is characterized in that, the described buffer area of step (2) comprises first buffer area and second buffer area, when data deposit in, deposit first buffer area earlier in, begin to deposit in second buffer area after first buffer area is filled with again, simultaneously the data of first buffer area are called away; First buffer area of restoring after second buffer area is filled with is called the data of second buffer area away simultaneously.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310149093XA CN103235174A (en) | 2013-04-26 | 2013-04-26 | Voltage online monitoring device for power system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310149093XA CN103235174A (en) | 2013-04-26 | 2013-04-26 | Voltage online monitoring device for power system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103235174A true CN103235174A (en) | 2013-08-07 |
Family
ID=48883225
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310149093XA Pending CN103235174A (en) | 2013-04-26 | 2013-04-26 | Voltage online monitoring device for power system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103235174A (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103558484A (en) * | 2013-11-16 | 2014-02-05 | 沈阳工业大学 | Substation cable lightning strike interference detecting device and method |
| CN104764915A (en) * | 2015-03-16 | 2015-07-08 | 中国计量学院 | Electronic type voltage transformer based on capacitor and resistance-capacitance voltage divider parallel connection |
| CN105137158A (en) * | 2015-07-24 | 2015-12-09 | 上海君世电气科技有限公司 | Power system temporary overvoltage monitoring system |
| CN105137164A (en) * | 2015-08-06 | 2015-12-09 | 江苏省电力公司苏州供电公司 | Voltage sag on-line monitoring device applied in power system |
| CN106771521A (en) * | 2016-12-15 | 2017-05-31 | 重庆大学 | A kind of substation equipment overvoltage aggregation of data acquisition system and method |
| CN109239447A (en) * | 2018-08-21 | 2019-01-18 | 上海赛璞乐电力科技有限公司 | A kind of power distribution network transient overvoltage monitoring system |
| CN112362956A (en) * | 2020-11-23 | 2021-02-12 | 云南电网有限责任公司临沧供电局 | Overvoltage detection method and system for metal oxide arrester based on three-level voltage division |
| CN112925293A (en) * | 2021-01-25 | 2021-06-08 | 东风电子科技股份有限公司 | Method, system, device, processor and storage medium for realizing detection aiming at different load feedback waveforms of BCM (binary coded modulation) |
| CN114509592A (en) * | 2022-04-20 | 2022-05-17 | 山东泰开互感器有限公司 | Capacitor voltage transformer with electric energy quality monitoring function |
| CN117650490A (en) * | 2023-11-22 | 2024-03-05 | 国网经济技术研究院有限公司 | Test system and method suitable for direct current operation control and protection system hanging net |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1434050A (en) * | 1972-09-07 | 1976-04-28 | Tokyo Electric Power Co | Electric power system supervisory control system comprising a/d converters at various points of the power system |
| CN1683936A (en) * | 2005-03-14 | 2005-10-19 | 西安交通大学 | On-line detecting method and its device for multiple path transient wave form over voltage of power system |
| CN102435814A (en) * | 2011-09-30 | 2012-05-02 | 中国电力科学研究院 | Device for measuring arc voltage of direct current circuit breaker |
-
2013
- 2013-04-26 CN CN201310149093XA patent/CN103235174A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1434050A (en) * | 1972-09-07 | 1976-04-28 | Tokyo Electric Power Co | Electric power system supervisory control system comprising a/d converters at various points of the power system |
| DE2365793A1 (en) * | 1972-09-07 | 1976-05-13 | Tokyo Electric Power Co | MEASURING VALUE RECORDERS AND CONVERTERS FOR CURRENT IN POWER SUPPLY LINES |
| CN1683936A (en) * | 2005-03-14 | 2005-10-19 | 西安交通大学 | On-line detecting method and its device for multiple path transient wave form over voltage of power system |
| CN102435814A (en) * | 2011-09-30 | 2012-05-02 | 中国电力科学研究院 | Device for measuring arc voltage of direct current circuit breaker |
Non-Patent Citations (1)
| Title |
|---|
| 黄涛等: "配网暂态过电压在线监测装置的研制", 《高电压技术》, vol. 34, no. 10, 31 October 2008 (2008-10-31), pages 2249 - 2252 * |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103558484A (en) * | 2013-11-16 | 2014-02-05 | 沈阳工业大学 | Substation cable lightning strike interference detecting device and method |
| CN104764915A (en) * | 2015-03-16 | 2015-07-08 | 中国计量学院 | Electronic type voltage transformer based on capacitor and resistance-capacitance voltage divider parallel connection |
| CN104764915B (en) * | 2015-03-16 | 2018-01-16 | 中国计量学院 | Based on the electric capacity electronic type voltage transformer in parallel with RC divider |
| CN105137158A (en) * | 2015-07-24 | 2015-12-09 | 上海君世电气科技有限公司 | Power system temporary overvoltage monitoring system |
| CN105137164A (en) * | 2015-08-06 | 2015-12-09 | 江苏省电力公司苏州供电公司 | Voltage sag on-line monitoring device applied in power system |
| CN106771521A (en) * | 2016-12-15 | 2017-05-31 | 重庆大学 | A kind of substation equipment overvoltage aggregation of data acquisition system and method |
| CN109239447A (en) * | 2018-08-21 | 2019-01-18 | 上海赛璞乐电力科技有限公司 | A kind of power distribution network transient overvoltage monitoring system |
| CN112362956A (en) * | 2020-11-23 | 2021-02-12 | 云南电网有限责任公司临沧供电局 | Overvoltage detection method and system for metal oxide arrester based on three-level voltage division |
| CN112925293A (en) * | 2021-01-25 | 2021-06-08 | 东风电子科技股份有限公司 | Method, system, device, processor and storage medium for realizing detection aiming at different load feedback waveforms of BCM (binary coded modulation) |
| CN112925293B (en) * | 2021-01-25 | 2022-09-06 | 东风电子科技股份有限公司 | Method, system, device, processor and storage medium for realizing detection aiming at different load feedback waveforms of BCM (binary coded modulation) |
| CN114509592A (en) * | 2022-04-20 | 2022-05-17 | 山东泰开互感器有限公司 | Capacitor voltage transformer with electric energy quality monitoring function |
| CN117650490A (en) * | 2023-11-22 | 2024-03-05 | 国网经济技术研究院有限公司 | Test system and method suitable for direct current operation control and protection system hanging net |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103235174A (en) | Voltage online monitoring device for power system | |
| CN101373197B (en) | Method and apparatus for on-line monitoring over voltage | |
| CN103424669A (en) | Route selection method for analyzing first principal component by utilizing principal component of zero-sequence current matrix of faulty feeder line | |
| CN101666826B (en) | Overvoltage online monitoring device based on dual time base sampling technology | |
| CN107621595A (en) | A kind of Condition assessment of insulation device and method of power cable | |
| CN101408565B (en) | 35KV power distribution station internal and external over voltage monitoring method based on voltage mutual inductor sampling | |
| CN101957396B (en) | On-line monitoring device and method for voltage quality of electric power system | |
| CN103344821A (en) | Transient overvoltage on-line monitoring system based on CVT and provided with built-in low-voltage capacitor | |
| CN105137158A (en) | Power system temporary overvoltage monitoring system | |
| CN201302591Y (en) | Over-voltage online monitoring device | |
| CN113109680B (en) | Partial discharge analysis system for stator winding of large-sized hydraulic generator | |
| CN101685108B (en) | Internal overvoltage online monitoring method for electric power system | |
| CN105527549A (en) | Partial discharge data collection circuit and detection system | |
| CN103712551A (en) | Power distribution network transformer low-voltage winding deformation on-line monitoring device and method | |
| CN105606955B (en) | A kind of faulty line method of discrimination based on numerical differentiation and empirical mode decomposition | |
| CN202649370U (en) | PT (potential transformer) secondary loop multipoint grounding online monitor | |
| CN202486278U (en) | Power distribution network cable insulation detection system | |
| CN202305704U (en) | Running state monitoring device of zinc oxide arrester | |
| CN102879710B (en) | System and method for detecting single-phase ground fault point of power distribution line | |
| CN102565592B (en) | A kind of technology-systematization verification short-circuit test method for intelligent substation | |
| CN100394201C (en) | Overvoltage on-line sampler for 6-35 KV electric power system | |
| CN104360145A (en) | Data acquisition card based voltage sag monitoring device | |
| Shu et al. | MMC-HVDC line fault identification scheme based on single-ended transient voltage information entropy | |
| CN205229398U (en) | Partial discharge data acquisition circuit and detecting system | |
| CN203224561U (en) | Online monitoring device for transient overvoltage of power distribution network |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20130807 |