CN109490811A - A kind of oil pressure monitoring method of inverted type current transformer - Google Patents
A kind of oil pressure monitoring method of inverted type current transformer Download PDFInfo
- Publication number
- CN109490811A CN109490811A CN201811405190.XA CN201811405190A CN109490811A CN 109490811 A CN109490811 A CN 109490811A CN 201811405190 A CN201811405190 A CN 201811405190A CN 109490811 A CN109490811 A CN 109490811A
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- mutual inductor
- oil pressure
- monitor device
- line monitor
- current transformer
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/02—Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
- G01L19/08—Means for indicating or recording, e.g. for remote indication
- G01L19/12—Alarms or signals
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Housings And Mounting Of Transformers (AREA)
Abstract
The present invention relates to transformer technical fields, specifically disclose a kind of oil pressure monitoring method of inverted type current transformer, detect oil pressure by pressure sensor, transfer data to mutual inductor on-Line Monitor Device；Mutual inductor on-Line Monitor Device shows data, and is analyzed and determined；Alarm is issued when mutual inductor on-Line Monitor Device detects that pressure is more than upper limit oil pressure value；Alarm is also issued when mutual inductor on-Line Monitor Device detects pressure lower than lower limit oil pressure value；The numerical value of acquisition and judging result are transmitted to host computer simultaneously by mutual inductor on-Line Monitor Device.The oil pressure monitoring method of oil pressure mutual inductor of the present invention is used to monitor the pressure of oil pressure in body in the bottom of mutual inductor setting pressure sensor, and pressure value is transmitted to mutual inductor on-Line Monitor Device and is analyzed, unusual condition is issued and is alarmed, it reminds substation inspection personnel to pay close attention in real time, is abnormal to prevent mutual inductor and causes electric power system fault.
Description
Technical field
The present invention relates to mutual inductor monitoring technical fields, and in particular to a kind of oil pressure monitoring side of inverted type current transformer
Method.
Background technique
Oil-immersed inverted current transformer is small in size, light-weight, good appearance, and the spy strong with resistance to dynamic and thermal stability ability
Point, has a vast market foreground.Oil-immersed inverted current transformer is paper oil insulation current transformer, and secondary coil passes through gold
Belong to shielding case package, be placed in the top of product, secondary coil introduces low-voltage side outlet box by an aluminum pipe, and shielding case and aluminum pipe are all
It is surrounded by capacitor type insulating, can effectively improve the field distribution in the entire short transverse in insulating sleeve surface.Due to oil immersion product
Electric discharge exception occurs for inside, and internal transformer oil, which can crack, generates the failure gas such as hydrogen, methane, and interiors of products oil pressure is caused to be sent out
Changing issues early warning in time, current transformer is avoided to send out so needing in real time to be monitored the oil pressure in current transformer
Raw exception causes electric power system fault.
Summary of the invention
The technical problem to be solved by the present invention is in view of the deficiencies of the prior art, provide a kind of inverted oil pressure mutual inductor
Oil pressure monitoring method, in the bottom of mutual inductor, setting pressure sensor is used to monitor the pressure of oil pressure in product, and by pressure
Value is transmitted to mutual inductor on-Line Monitor Device and is analyzed, and issues and alarms to unusual condition, reminds operator to pay close attention in real time, subtracts
Less since oil pressure problem causes to damage to mutual inductor.
In order to solve the above technical problems, the present invention provides a kind of oil pressure monitoring method of inverted type current transformer, it will
Pressure sensor is mounted on the fuel outlet valve of current transformer bottom, and specific monitoring process is as follows:
S1, the oil pressure in current transformer is detected by pressure sensor, and transfers data to mutual inductor on-line monitoring dress
It sets；
S2, mutual inductor on-Line Monitor Device show data, and are analyzed and determined；
S3, detect that the incoming mutual inductor internal oil pressure of pressure sensor is more than normal work when mutual inductor on-Line Monitor Device
Make mutual inductor on-Line Monitor Device when the upper limit oil pressure value of state and issues alarm；When mutual inductor on-Line Monitor Device detects pressure
When the incoming mutual inductor internal oil pressure of sensor is lower than the lower limit oil pressure value of normal operating conditions, mutual inductor on-Line Monitor Device hair
It alarms out；
The numerical value of acquisition and judging result are transmitted to host computer simultaneously by S4, mutual inductor on-Line Monitor Device, and host computer is protected
It deposits the data received and carries out real-time display, the real-time monitoring signal that host computer processing mutual inductor on-Line Monitor Device issues is gone forward side by side
Row comprehensive analysis and processing judge mutual inductor internal pressure variation tendency, and it is concurrent to carry out trending early warning to mutual inductor abnormality
Pre-warning signal reminds fortune inspection personnel out.
Further, the host computer includes facility information module, data disaply moudle, parameter setting module and history number
According to enquiry module,
Facility information module: the basic information of equipment is established；
Data disaply moudle: receive voltage data, matched curve slope, and carry out real-time display；
Parameter setting module: parameter setting window, device address, sampling interval, alarming threshold value parameter setting are provided；
The inquiry of historical data module: according to date or equipment id enquiry of historical data, data variation tendency information.
Further, the pressure sensor is mounted on the bottom of current transformer by three-way connection.
Further, the upper limit oil pressure value is 0.02MPa, and the lower limit oil pressure value is -0.02MPa.
Specifically, the mutual inductor on-Line Monitor Device monitors several current transformers simultaneously.
Further, the mutual inductor on-Line Monitor Device also has same set product pressure warning function, and the pressure is pre-
Alert function is to sample according to setting sample frequency to the current transformer of same group of operation, and be transferred to host computer, host computer
It finds out and judges that the pressure fitting a straight line in period obtains its slope, to corresponding electric current after being compared and analyzed to same group of slope
Mutual inductor issues abnormity early warning.
The beneficial effects of the present invention are: the oil pressure monitoring method of oil pressure mutual inductor of the present invention is easy to operate, essence in real time is monitored
Standard, high degree of automation, in the bottom of mutual inductor, setting pressure sensor is used to monitor the pressure of oil pressure in mutual inductor, and will pressure
Force value is transmitted to mutual inductor on-Line Monitor Device and is analyzed, and issues and alarms to unusual condition, reminds substation inspection personnel real
When pay close attention to, be abnormal to prevent mutual inductor and cause electric power system fault；The pressure sensor measurement used in oil pressure monitoring apparatus
Range is wide, and test error is small, and test repeatability is good, ensure that the accuracy of oily pressure monitoring system work.
Detailed description of the invention
It, below will be to required in embodiment or description of the prior art in order to illustrate more clearly of technical solution of the present invention
The attached drawing used is briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, right
For those of ordinary skill in the art, without creative efforts, it can also be obtained according to these attached drawings
Its attached drawing.
Fig. 1 is the method flow diagram of oil pressure monitoring method of the present invention；
Fig. 2 is the detection device scheme of installation of oil pressure monitoring method of the present invention.
Specific embodiment
Below in conjunction with Figure of description, technical scheme in the embodiment of the invention is clearly and completely described, shows
So, described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based on the reality in the present invention
Apply example, those of ordinary skill in the art's every other embodiment obtained without creative labor, all
Belong to the scope of protection of the invention.
In a specific embodiment of the present invention, as shown in Figure 1 to Figure 2, the invention particularly discloses a kind of inverted electric currents
The oil pressure monitoring method of mutual inductor, pressure sensor is mounted on the fuel outlet valve of current transformer bottom, the pressure sensing
Device is mounted on fuel outlet valve by three-way connection, and the measurement range of the preferred pressure sensor of the present invention is 0.05MPa~0.3MPa,
Measurement error is och0.5%, and test data relative standard deviation RSD < 2%, this sensor measurement range is wide, and test error is small,
Test repeatability is good, ensure that the accuracy of oily pressure monitoring system work.
The specific monitoring process of oil pressure monitoring method is as follows:
S1, the oil pressure in current transformer is detected by pressure sensor, and transfers data to mutual inductor on-line monitoring dress
It sets；
S2, mutual inductor on-Line Monitor Device show to data, and are analyzed and determined that preferably mutual inductor is monitored on-line
Device is main by sensing unit, power supply unit, central processing unit, data acquisition unit, data transmission unit and monitoring unit
Component composition；
S3, detect that the incoming mutual inductor internal oil pressure of pressure sensor is more than normal work when mutual inductor on-Line Monitor Device
When making the upper limit oil pressure value of state, mutual inductor on-Line Monitor Device issues alarm, and Field Force is reminded to further confirm that product shape
State, and real-time tracking product pressure situation；Preferably upper limit oil pressure value is 0.02MPa；When mutual inductor on-Line Monitor Device detects
When the mutual inductor internal oil pressure being passed to pressure sensor is lower than the lower limit oil pressure value of normal operating conditions, mutual inductor on-line monitoring
Device issues alarm, reminds Field Force to check that product whether there is leakage of oil problem, preferred lower limit oil pressure value is -0.02MPa；
The numerical value of acquisition and judging result are transmitted to host computer simultaneously by S4, mutual inductor on-Line Monitor Device, and host computer is protected
It deposits the data received and carries out real-time display, the real-time monitoring signal that host computer processing mutual inductor on-Line Monitor Device issues is gone forward side by side
Row comprehensive analysis and processing judge mutual inductor internal pressure variation tendency, and it is concurrent to carry out trending early warning to mutual inductor abnormality
Pre-warning signal reminds fortune inspection personnel out.
The host computer includes facility information module, data disaply moudle, parameter setting module and the inquiry of historical data mould
Block,
Facility information module: establishing the basic information of equipment, according to user's needs, establishes the relevant information of each equipment；
Data disaply moudle: receive voltage data, matched curve slope, and carry out real-time display, if any data over run report
It is alert then shown with red display and yellow early warning；
Parameter setting module: parameter setting window, device address, sampling interval, alarming threshold value parameter setting are provided；
The inquiry of historical data module: according to date or equipment id enquiry of historical data, data variation tendency information.
The mutual inductor on-Line Monitor Device can monitor the oil pressure of several current transformers simultaneously, and preferably three are one
Group, the bottom of three current transformers are respectively equipped with pressure sensor, and it is online that three pressure sensors are connected to mutual inductor simultaneously
Monitoring device.
The mutual inductor on-Line Monitor Device also has same set product (3 current transformers) pressure warning function, described
Pressure warning function is to sample according to setting sample frequency to the current transformer of same group of operation, and be transferred to host computer,
Host computer, which is found out, judges that the pressure fitting a straight line in period obtains its slope, and after comparing and analyzing to same group of slope, to institute
Corresponding current transformer issues abnormity early warning.
Slope intermediate value is specially chosen as benchmark is judged, and (there may be internal low energy to discharge for the maximum product of slope value
The case where failure, transformer oil cracks, there may be the failures of oil leak for the smallest product of slope value, therefore choose slope intermediate value most
It is reliable).If 2 times of gradient maxima >=slope intermediate value, system issues product corresponding to gradient maxima abnormal pre-
It is alert, remind operation maintenance personnel to check Product Status；If 0.5 times of slope minimum value≤slope intermediate value, system is to slope minimum value
Corresponding product issues abnormity early warning, and operation maintenance personnel is reminded to check Product Status.
The beneficial effects of the present invention are: the oil pressure monitoring method of oil pressure mutual inductor of the present invention is easy to operate, essence in real time is monitored
Standard, high degree of automation, in the bottom of mutual inductor, setting pressure sensor is used to monitor the pressure of oil pressure in mutual inductor, and will pressure
Force value is transmitted to mutual inductor on-Line Monitor Device and is analyzed, and issues and alarms to unusual condition, reminds substation inspection personnel real
When pay close attention to, be abnormal to prevent mutual inductor and cause electric power system fault；The pressure sensor measurement used in oil pressure monitoring apparatus
Range is wide, and test error is small, and test repeatability is good, ensure that the accuracy of oily pressure monitoring system work.
The above is a preferred embodiment of the present invention, it is noted that for those skilled in the art
For, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also considered as
Protection scope of the present invention.
Claims (6)
1. pressure sensor is mounted on putting for current transformer bottom by a kind of oil pressure monitoring method of inverted type current transformer
On oil valve, which is characterized in that specific monitoring process is as follows:
S1, the oil pressure in current transformer is detected by pressure sensor, and transfers data to mutual inductor on-Line Monitor Device；
S2, mutual inductor on-Line Monitor Device show data, and are analyzed and determined；
S3, detect that the incoming mutual inductor internal oil pressure of pressure sensor is more than to work normally shape when mutual inductor on-Line Monitor Device
Mutual inductor on-Line Monitor Device issues alarm when the upper limit oil pressure value of state；When mutual inductor on-Line Monitor Device detects pressure sensing
When the incoming mutual inductor internal oil pressure of device is lower than the lower limit oil pressure value of normal operating conditions, mutual inductor on-Line Monitor Device issues report
It is alert；
The numerical value of acquisition and judging result are transmitted to host computer simultaneously by S4, mutual inductor on-Line Monitor Device, and host computer preservation connects
The data being subject to carry out real-time display, and the real-time monitoring signal that host computer processing mutual inductor on-Line Monitor Device issues simultaneously carries out comprehensive
Analysis and processing are closed, judges mutual inductor internal pressure variation tendency, trending early warning is carried out to mutual inductor abnormality and is issued pre-
Alert signal reminds fortune inspection personnel.
2. a kind of oil pressure monitoring method of inverted type current transformer according to claim 1, which is characterized in that on described
Position machine includes facility information module, data disaply moudle, parameter setting module and the inquiry of historical data module,
Facility information module: the basic information of equipment is established；
Data disaply moudle: receive voltage data, matched curve slope, and carry out real-time display；
Parameter setting module: parameter setting window, device address, sampling interval, alarming threshold value parameter setting are provided；
The inquiry of historical data module: according to date or equipment id enquiry of historical data, data variation tendency information.
3. a kind of oil pressure monitoring method of inverted type current transformer according to claim 1, which is characterized in that the pressure
Force snesor is mounted on the bottom of current transformer by three-way connection.
4. a kind of oil pressure monitoring method of inverted type current transformer according to claim 1, which is characterized in that on described
Limit oil pressure value is 0.02MPa, and the lower limit oil pressure value is -0.02MPa.
5. a kind of oil pressure monitoring method of inverted type current transformer according to claim 1, which is characterized in that described mutual
Sensor on-Line Monitor Device monitors several current transformers simultaneously.
6. a kind of oil pressure monitoring method of inverted type current transformer according to claim 5, which is characterized in that described mutual
Sensor on-Line Monitor Device also has same set product pressure warning function, and the pressure warning function is according to setting sample frequency
The current transformer of same group of operation is sampled, and is transferred to host computer, host computer, which is found out, judges that the pressure fitting in period is straight
Line obtains its slope, issues abnormity early warning to corresponding current transformer after comparing and analyzing to same group of slope.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811405190.XA CN109490811B (en) | 2018-11-23 | 2018-11-23 | Oil pressure monitoring method of inverted current transformer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811405190.XA CN109490811B (en) | 2018-11-23 | 2018-11-23 | Oil pressure monitoring method of inverted current transformer |
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| CN109490811A true CN109490811A (en) | 2019-03-19 |
| CN109490811B CN109490811B (en) | 2021-08-13 |
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| CN201811405190.XA Active CN109490811B (en) | 2018-11-23 | 2018-11-23 | Oil pressure monitoring method of inverted current transformer |
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Cited By (5)
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| CN110060858A (en) * | 2019-04-11 | 2019-07-26 | 国网辽宁省电力有限公司电力科学研究院 | Oil-immersed current transformer internal abnormality judgment means based on accurate oil pressure acquisition method |
| CN110609126A (en) * | 2019-11-01 | 2019-12-24 | 国网江苏省电力有限公司电力科学研究院 | Online monitoring system for hydrogen in mutual inductor and method for judging internal fault of mutual inductor |
| CN110631762A (en) * | 2019-11-01 | 2019-12-31 | 国网江苏省电力有限公司电力科学研究院 | Method for determining internal pressure criterion for mutual inductor fault early warning |
| CN112285631A (en) * | 2020-09-29 | 2021-01-29 | 上海许继电气有限公司 | Judgment method and system for active early warning of current transformer |
| CN112649040A (en) * | 2020-11-23 | 2021-04-13 | 中国电力科学研究院有限公司武汉分院 | Device and method for monitoring state of oil-immersed inverted current transformer |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110060858A (en) * | 2019-04-11 | 2019-07-26 | 国网辽宁省电力有限公司电力科学研究院 | Oil-immersed current transformer internal abnormality judgment means based on accurate oil pressure acquisition method |
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| CN112649040A (en) * | 2020-11-23 | 2021-04-13 | 中国电力科学研究院有限公司武汉分院 | Device and method for monitoring state of oil-immersed inverted current transformer |
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