CN110071481A - A kind of digital gaseous shield of power transformer and method - Google Patents
A kind of digital gaseous shield of power transformer and method Download PDFInfo
- Publication number
- CN110071481A CN110071481A CN201910375867.8A CN201910375867A CN110071481A CN 110071481 A CN110071481 A CN 110071481A CN 201910375867 A CN201910375867 A CN 201910375867A CN 110071481 A CN110071481 A CN 110071481A
- Authority
- CN
- China
- Prior art keywords
- module
- digital
- signal
- oil stream
- transient state
- 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.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/40—Structural association with built-in electric component, e.g. fuse
- H01F27/402—Association of measuring or protective means
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/04—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Housings And Mounting Of Transformers (AREA)
Abstract
A kind of digital gaseous shield of power transformer and method, including transient state oil stream feature measurement module, switching input module, signal condition and acquisition module, digital core module, external communication interface module, human-computer dialogue module and switching value output module；Transient state oil stream feature measurement module is connected with signal condition with acquisition module, and signal condition is connected with digital core module with acquisition module, switching input module, external communication interface module, human-computer dialogue module and switching value output module.The present invention obtains transient state oil stream digital information inside conservator connecting tube in real time; operation obtains the oil stream actuating quantity of characterization oil flow surge intensity; protection philosophy and criterion are constructed using significant difference existing for the actuating quantity under transformer difference service condition; it realizes reliable, quick, the sensitive examination and excision to oil tank of transformer internal fault, and is not influenced by excitation surge current.
Description
Technical field
The invention belongs to field of power system, it is related to a kind of digital gaseous shield of power transformer and method, uses
In reliable, quick, sensitive examination oil-immersed power transformer oil tank internal fault.
Background technique
As a kind of main apparatus of key, transformer occupies very important status in the power system, it steady
Fixed operation is to guarantee entire electric system electric energy reliable transmission, flexible allocation, the important prerequisite of safe handling.When transformer occurs
When internal fault, if protective relaying device tripping or cannot act in time, transformer body may be because of internal fault pressure
It impacts and is damaged, or even cause explosion, fire accident；On the other hand, once protective device is under the conditions of non-internal fault
It malfunctions, because economic loss caused by having a power failure will be inevitable.Particularly with voltage levels, the hinge transformation of large capacity
Device, is involved great expense, structure is complicated due to itself, and has a large amount of loads, and relay fail or malfunction no matter occurs, all will be serious
Influence the safe and stable operation of electric system.Therefore, study and explore the transformation of high reliablity, quick action and high sensitivity
Device protection has a very important significance.
Power transformer interior fault process is with there are three main features: phase current increases, spill current increases and failure gas
The generation of body.For these three notable features, relay protection workers devise overcurrent protection, differential protection and non-electrical
Amount protection etc..The non-electrical measure feature such as inside transformer oil stream, temperature, pressure changes therewith during failure gas generates is
Failure electric energy is converted into the specific manifestation of the other forms energy such as interior energy, kinetic energy, potential energy.Failure weak for inside transformer and
Speech, since fault power is smaller, is only often difficult to sensitive examination with electric quantity protective.But the fault energy for passing through a period of time
Accumulation, the non-electrical measure feature changes such as more apparent oil flow surge will occur in oil tank of transformer inside, temperature increases, pressure increases
Change.Therefore, often there is higher sensitivity compared with electrical quantity protection using non electrical quantity feature construction tranformer protection.In addition, making
For lumped elements important in electric system, power transformer is that collection winding, iron core, insulation, fuel tank, switch, cooler etc. are more
The expensive device that a component is integrated.Its failure mode often shows as each component and Superheated steam drier occurs: such as electrical steel piece
Between overheat, winding is blown, tapping switch contact melts or burns；Or there are mechanical faults: core construction loosening, coiling machine
Tool deformation or collapsing, oil tank of transformer cracking oil leak etc..When facing non-electrical network failure, electrical quantity protection is often difficult to can
By screening, and based on the features non-ionizing energy loss such as flow velocity, temperature, pressure then can more fully, directly react on transformer
Malfunction.
Therefore, early in nineteen twenty-one, German transformer expert Max Buchholz has just invented Buchholz relay, and is pacified
In connecting tube between transformer main fuel tank and conservator, it is primarily adapted for use in conservator and top of oil-tank is without the gas compartment
Large Oil immersion transformer makes up electrical quantity protection to protect various types of internal faults outside electrical quantity protection sensitive volume
Existing deficiency.The existing think of of relay protection research has been widened based on the gaseous shield that power transformer interior fault gas generates
Road is widely used in oil-immersed power transformer by sensitivity advantage.Regulation " relay protection of power equipment and automatic device
Design specification " clear stipulaties: capacity is oil-immersed transformer in the workshop of 0.4MVA or more, capacity is 0.8MVA's or more
The oil-filled tap changer of oil-immersed transformer and on-load adjustable transformer should all install protection, when shell internal fault produces
When raw slight gas or pasta decline, answer snap action in signal；When generating a large amount of gas, should act each in disconnecting transformer
Side breaker.
Now widely used Buchholz relay still continues to use the basic principle and machinery of Buchholz relay before a century
Structure, but with the high speed development of electric system for decades, existing machinery formula protection be increasingly difficult to meet large capacity,
Requirements at the higher level of the voltage levels power transformer to its protective value.The transformer to take place frequently in recent years is quick-fried because of internal fault generation
Fried, fire accident occurs malfunction trip accident because of external short circuit failure and shows that tradition machinery formula protection is primarily present
Principle defect, the problems such as taking threshold value and mechanical structure action performance low by rule of thumb, protective value be increasingly difficult to
Meet the requirements at the higher level of current large capacity, voltage levels power transformer.Tradition machinery formula protection utilizes floating ball, bullet
The mechanical structures such as spring, baffle incude gas generation and oil flow surge, are primarily present two aspect problems: first, spring mechanism is only capable of
The size of oil stream flow velocity is reacted, once being more than that preset threshold issues trip signal, do not measure, analyze oil flow surge variation spy
Reference breath, therefore protection reliability is lower；Second, mechanical structure long period of soaking is in insulating oil, oxide shedding and insulation
The greasy filth that oil is deteriorated and generated will be attached on the mechanical components such as relay baffle, float or spring, seriously affect its movement
Accuracy and sensitivity.Therefore, there is an urgent need to develop a kind of digital gaseous shield, will in the past by rule of thumb with feel structure
At mechanical protection be increased to quantitative analysis, high reliability determines, new stage of Digital Realization.
Summary of the invention
The object of the present invention is to provide a kind of digital gaseous shield of power transformer and methods, can be reliable, fast
Fast, sensitive examination oil-immersed power transformer oil tank internal fault.
To achieve the above object, the present invention adopts the following technical scheme that:
A kind of digital gaseous shield of power transformer, comprising: transient state oil stream feature measurement module, switching value are defeated
Enter module, signal condition and acquisition module and digital core module；Wherein, transient state oil stream feature measurement module and signal tune
Reason is connected with acquisition module, and signal condition is connected with digital core module with acquisition module and switching input module；
Transient state oil stream feature measurement module becomes for transient state oil stream inside real time high-speed measuring transformer conservator connecting tube
Change feature, and exports corresponding analog voltage/current signal；Transient state oil stream feature measurement module is by outer bundle type high frequency
Ultrasonic flowmeter, flowmeter transmitters and communications cable composition；
The analog voltage/current that signal condition and acquisition module are used to receive the output of transient state oil stream feature measurement module is believed
Number, and it is converted into the standardized digital signal that digital core module can identify, then outputting standard digital signal；
Switching input module is used to acquire the related switch amount signal that knows of needs, and output it as high level 1 or
Low level 0, the input digital quantity as digital core module；
After digital core module is for receiving input digital quantity and standardized digital signal, protection operation is executed, number is completed
Signal processing tasks, and then realize relay protection function.
A further improvement of the present invention lies in that outer bundle type high frequency ultrasound wave flowmeter is mounted on installation for transformer connecting tube
On, outer bundle type high frequency ultrasound wave flowmeter is connected with flowmeter transmitters, and flowmeter transmitters are connected with the communications cable.
A further improvement of the present invention lies in that the measurement frequency of outer bundle type high frequency ultrasound wave flowmeter is 100Hz or more, survey
Error is measured less than 1%, operating temperature is -30~80 DEG C, and flow velocity range is -20~20m/s.
A further improvement of the present invention lies in that signal condition and acquisition module are by connecting terminal, signal conditioning circuit, low pass
Filter, signal sample circuit and modulus A/D conversion circuit composition；Connecting terminal is connected with signal conditioning circuit, signal tune
Reason circuit is connected with low-pass filter, and low-pass filter is connected with signal sample circuit, and signal sample circuit and modulus A/D are converted
Circuit is connected, and modulus A/D conversion circuit is connected with digital core module；Connecting terminal is also connected with the communications cable.
A further improvement of the present invention lies in that digital core module by bus, central processing unit, timer/counter, with
Machine memory, read-only memory and control circuit composition；Bus includes data/address bus, address bus and control bus, reality
Existing data exchange and operation control；Central processing unit utilizes chip microprocessor, general purpose microprocessor or digital signal processor
Realize Digital Signal Processing；Timer/counter is used to provide timing sampling trigger signal, is formed and interrupt, protect deferred action
Timing；Random access memory is for keeping in ephemeral data, data information, calculation processing including signal condition and acquisition module input
The intermediate result of process；It is read-only memory for saving data；Control circuit can by Complex Programmable Logic Devices or scene
Programming gate array realizes the connection and co-ordination of entire digital circuit.
A further improvement of the present invention lies in that further including the external communication interface module being connected with digital core module, people
Machine session module and switching value output module；
External communication interface module is to provide the information channel with computer communication network and telecommunicatio network；
Human-computer dialogue module is used for the informational linkage established between digital protection equipment and user；
Switching value output module controls the on-off for executing trip(ping) circuit for 0 or 1 state by output.
A further improvement of the present invention lies in that human-computer dialogue module includes compact keyboard, display screen, indicator light, button, beats
Print machine interface and debugging communication interface；Switching value output module is made of photoelectric isolating device and exit relay, photoelectricity
Isolating device is connected with exit relay.
A kind of guard method based on the above-mentioned digital gaseous shield of power transformer, comprising the following steps:
1. transient state oil stream variation characteristic inside transient state oil stream feature measurement module real-time measurement installation for transformer connecting tube,
And export corresponding analog voltage/current signal；Signal condition and acquisition module receive transient state oil stream feature measurement
The analog voltage/current signal of module output, and it is converted into the standardized digital signal that digital core module can identify, then
Outputting standard digital signal；After digital core module receives input digital quantity and standardized digital signal, temporary blocking defencive function,
Sampled data buffer area is waited to have the data of one or two cycle, then open and protection function；
2. more current t moment oil stream flow velocity vms(t) with starting threshold vstBetween amplitude size relation, i.e., by sentencing
Whether whether disconnected formula (1) start at the digital protection of Rob Roy decision, if formula (1) is set up, active flag set is entered step
③；
vms(t)-vst≥0 (1)
3. calculating the oil stream actuating quantity v of current t moment using formula (2)op(t), compare oil stream actuating quantity vop(t) it and protects
Threshold value vthBetween amplitude size relation, that is, judge formula (3) whether at Rob Roy screen oil tank of transformer internal fault；If formula
(3) it sets up, then issues trip signal, the whole series protection involution waits manual reset；
In formula (2), T is data window length, and f is the signal sampling frequencies of acquisition module；
vop(t)/kre≥vth (3)
In formula (3), kreTo protect safety factor；vthFor digital protection threshold value.
A further improvement of the present invention lies in that starting threshold v in formula (1)stFor 0.2~0.4m/s.
A further improvement of the present invention lies in that protecting safety factor k in formula (3)reIt is 1.2.
Compared with prior art, the invention has the benefit that
The present invention is using external clamping high frequency ultrasound wave flowmeter under the premise of not destroying transformer existing structure integrality
Realize the digital real-time measurement to oil stream inside conservator connecting tube.Compared to the spring knot of tradition machinery formula Buchholz relay
Structure long period of soaking is in insulating oil, and ultrasonic flowmeter is not contacted with insulating oil directly in the present invention, on the one hand, indirect type is surveyed
Amount mode not will cause the loss of flow velocity kinetic energy；On the other hand, the greasy filth that oxide shedding and insulating oil are deteriorated and generated will
Without being adhered in measuring device, therefore apparatus of the present invention have higher flow velocity measurement accuracy, induction sensitivity and long-term
Operational reliability and stability.The present invention overcomes tradition machinery formula non-ionizing energy loss using in last 100 years in the prior art
Although successfully protecting ten hundreds of oil-immersed transformers in journey, due to there are theoretical modeling difficulty, principle defect, with
Experience takes the problems such as threshold value and insufficient mechanical structure action performance, is increasingly difficult to meet current large capacity, high voltage etc.
The problem of requirements at the higher level of grade power transformer.Simultaneously because of system blackout, Explosion of Transformer caused by relay fail, maloperation
Accident happens occasionally, and seriously affects the safe and reliable operation of electric system, seriously threatens substation operation personnel and people around
The problem of people's masses' security of the lives and property.
The present invention is realized pair by high frequency ultrasound wave flowmeter under the premise of not destroying transformer existing structure integrality
The real-time measurement of oil stream inside conservator connecting tube.Protective device of the invention independently of electric power networks, the measurement of oil stream feature and
Signal transmission be disturbed it is smaller, also not to electric system harmonic；Data acquisition element, oil stream operational analysis element are complete
It can satisfy requirement that is quick, handling multi-path, high-frequency data in real time.
Further, the present invention is 100Hz or more by using measurement frequency, and measurement error is less than 1%, operating temperature
It is -30~80 DEG C, flow velocity range is that the flowmeter of -20~20m/s measures, and outer bundle type high frequency ultrasound wave flowmeter can be
Do not destroy the real-time measurement realized under the premise of installation for transformer connecting pipe structure integrality to oil stream flow velocity, meanwhile, no matter from
Precision or use scope high frequency ultrasound wave flowmeter can meet power transformer ontology high temperature, strong electromagnetic environmental requirement.
The present invention is devised comprising transient state oil stream feature measurement module, switching input module, signal condition and acquisition
The digital gaseous shield of module, digital core module, controls hardware system according to protection philosophy and functional requirement
System, to protective device monitoring, troubleshooting, human-computer dialogue, communication, self-test, accident record and analysis report and debugging function,
Using oil stream inside conservator connecting tube transient changing information and at different operating conditions the flow velocity difference that occurs realizes pair
Quick, sensitive, the reliable examination of oil tank of transformer internal fault, and do not influenced by excitation surge current.The principle of the invention is simple, device
It is easily achieved, mechanical watt will constituted by rule of thumb with feeling in the past under the premise of not destroying transformer existing structure integrality
This protection is increased to quantitative analysis, high reliability determines, the new stage of Digital Realization, to adapt to current and future great Rong
Amount, requirement of the voltage levels power transformer to protection " four property ".The present invention overcomes traditional Buchholz relays can only
Flow velocity size is incuded by mechanical spring arrangement and can only export switching value information, and single flow velocity amplitude often can not be distinguished correctly
Area's internal and external fault of transformer, the problem of so as to cause false protection or tripping.
Detailed description of the invention
Fig. 1 is system structure schematic diagram of the invention.
Fig. 2 is flow chart of the invention.
Fig. 3 is the digital gaseous shield field demonstration result of power transformer.
Specific embodiment
Present invention will now be described in detail with reference to the accompanying drawings..
Bundle type high frequency ultrasound wave flowmeter in China and foreign countries' of the present invention is also referred to as external clamping high frequency ultrasound wave flowmeter.
Referring to Fig. 1, a kind of digital gaseous shield of power transformer, comprising: transient state oil stream feature measurement module,
Switching input module, signal condition and acquisition module, digital core module, external communication interface module, human-computer dialogue module
And switching value output module.Wherein, transient state oil stream feature measurement module and signal condition are connected with acquisition module, signal tune
It manages equal with acquisition module, switching input module, external communication interface module, human-computer dialogue module and switching value output module
It is connected with digital core module；
Transient state oil stream feature measurement module becomes for transient state oil stream inside real time high-speed measuring transformer conservator connecting tube
Change feature, and exports corresponding analog voltage/current signal；
Transient state oil stream feature measurement module is by outer bundle type high frequency ultrasound wave flowmeter, flowmeter transmitters and communication line
Cable composition, outer bundle type high frequency ultrasound wave flowmeter are mounted in installation for transformer connecting tube, outer bundle type high frequency ultrasound wave flowmeter
It is connected with flowmeter transmitters, flowmeter transmitters are connected with the communications cable.It is real-time using outer bundle type high frequency ultrasound wave flowmeter
Transient state oil stream variation characteristic inside high speed measuring transformer conservator connecting tube, using flowmeter transmitters and communications cable output with
Corresponding analog voltage/current signal.For reliability, quick-action and the sensitivity for guaranteeing protective device, high frequency ultrasound
The measurement frequency of wave flowmeter need to reach 100Hz or more, and measurement error need to be less than 1%, and operating temperature need to reach -30~80 DEG C,
Flow velocity range need to reach -20~20m/s.
The related switch amount signal that switching input module acquisition needs to know, and output it by photoelectric isolating device
Input digital quantity for high level " 1 " or low level " 0 ", as digital core module.
Signal condition and acquisition module by connecting terminal, signal conditioning circuit, low-pass filter, signal sample circuit and
Modulus (A/D) conversion circuit composition.Connecting terminal is connected with signal conditioning circuit, signal conditioning circuit and low-pass filter phase
Even, low-pass filter is connected with signal sample circuit, and signal sample circuit is connected with modulus (A/D) conversion circuit, and modulus A/D turns
Circuit is changed to be connected with digital core module；Connecting terminal is also connected with the communications cable.Signal condition is with acquisition module for receiving
The analog voltage/current signal of transient state oil stream feature measurement module output, and be converted into digital core module and can know
Other standardized digital signal, then outputting standard digital signal.
Digital core module is by bus, central processing unit (CPU), timer/counter, random access memory (RAM), read-only
Memory (ROM) and control circuit composition.Bus includes data/address bus, address bus and control bus, realizes that data are handed over
Change and operate control etc..Central processing unit (CPU) is commander's maincenter of digital core module, can use chip microprocessor,
The devices such as general purpose microprocessor and digital signal processor (DSP) realize Digital Signal Processing real-time, quickly.Timer/counting
Device is used to provide timing sampling trigger signal, is formed and interrupt, protect the functions such as deferred action exact timing.Random access memory
(RAM) for the temporary a large amount of ephemeral datas for needing fast exchange, the data information inputted including signal condition and acquisition module,
The intermediate result etc. of calculation processes.Read-only memory (ROM) is for saving data；Control circuit can be compiled by complexity
The effective connection and coordination work of the entire digital circuit of the realizations such as journey logical device (CPLD) or field programmable gate array (FPGA)
Make.
Digital core module completes number letter for executing protection operation after receiving input digital quantity and standardized digital signal
Number processing task, commands the normal operation of adjacent modules, realizes data exchange and operation control, and then realize relay protection function
Energy.
External communication interface module is made of computer network communication interface and defencive function private communication interface, to mention
For the information channel with computer communication network and telecommunicatio network, realize information exchange, data sharing, remote operation and
The functions such as remote maintenance.
Human-computer dialogue module includes compact keyboard, display screen, indicator light, printer interface and debugging communication interface etc..
For establishing the informational linkage between digital protection equipment and user, so that operations staff is to the artificial behaviour of protective device
Make, debug and obtain information feedback etc..
Switching value output module is made of photoelectric isolating device and exit relay, passes through " 0 " of output or one state
Come control execute trip(ping) circuit " logical " or " disconnected ", realize the action message of protection.
Referring to fig. 2, the guard method based on above-mentioned protective device, according to protection philosophy and functional requirement to monitoring device into
Row control, data acquisition, PERCOM peripheral communication, digital operation, logic judgment and action command execution etc. are every in an orderly manner grasps
Make, the specific steps are as follows:
1. it is initial that system is first carried out after power turn-on (referred to as powering on) or hardware reset (referred to as resetting) in protective device
Change, device is made to be in normal operating conditions.
2. executing comprehensive self-test after powering on, correctness, integrity detection are carried out to itself working condition, if discovery device
Defect then issues alarm signal and is latched whole device, waits technical staff's debugging, manual reset.
3. if data acquisition initialization is executed, and start timing sampling interruption, by self-test to save hits to circulation
Address distribution is carried out according to buffer area, setting indicates the dynamic address pointer of current latest data, then by the sampling period to control
The Abort Timer assignment of circulating sampling simultaneously enables its starting, open Sampling interrupt；
4. transient state oil stream variation inside transient state oil stream feature measurement module real time high-speed measuring transformer conservator connecting tube
Feature, and export corresponding analog voltage/current signal；Signal condition and acquisition module receive transient state oil stream characteristic quantity
The analog voltage/current signal of measurement module output, and it is converted into the standard digital letter that digital core module can identify
Number, then outputting standard digital signal；After digital core module receives input digital quantity and standardized digital signal, temporary blocking protection
Function waits sampled data buffer area to have enough data (data of one or two cycle), then open and protection function；
5. whole group initializes, operation self-test is carried out, device under operating status is detected, is sent out if finding device defect
Alarm signal and it is latched whole device out, waits technical staff's debugging, manual reset.
6. executing communication task processing if without failure, carry out data preparation is sent and received for information.
7. executing man-machine dialog process, it is scanned keyboard, control button, shows the tasks such as data in display screen, and is right
Various operational orders explain and classify, and deliver corresponding task by task category and handle.
8. judging whether protective device is in working operating mode.If not working operating mode then carries out at debugging task
Reason, return step is 5. after the completion of debugging task；If being in working operating mode, enter step 9..
9. differentiate active flag whether set, illustrate that protective device is having detected that possible accident before if set
Disturbance, enters step；Otherwise it enters step 10..
10. more current t moment oil stream flow velocity vms(t) with starting threshold vstBetween amplitude size relation, i.e., by sentencing
Whether whether disconnected formula (1) start at the digital protection of Rob Roy decision, if formula (1) is invalid, return step is 5.；If formula (1)
It sets up, active flag set enters step。
vms(t)-vst≥0 (1)
In formula (1), start threshold vstIt can be selected in 0.2~0.4m/s flow rates according to the caliber size of conservator connecting tube
It takes.
The oil stream actuating quantity v of current t moment is calculated using formula (2)op(t).Compare vop(t) with protection threshold value vthIt
Between amplitude size relation, that is, judge formula (3) whether at Rob Roy screen oil tank of transformer internal fault.If formula (3) is set up, send out
Trip signal out, the whole series protection involution, waits manual reset；Otherwise return step is 5..
In formula (2), T is data window length.F is the signal sampling frequencies of acquisition module.
vop(t)/kre≥vth (3)
In formula (3), kreTo protect safety factor, 1.2 are usually taken.vthIt, can be according to oil for digital protection threshold value
It rests the head on country that the caliber size of connecting tube is protected referring to mechanical Buchholz relay grave gas or professional standard is chosen.
The present invention is by transient state oil stream feature measurement module, switching input module, signal condition and acquisition module, number
Nucleus module, external communication interface module, human-computer dialogue module and switching value output module.It is wanted according to protection philosophy and function
It asks and protective device is controlled, realize to the system monitoring of protective device, troubleshooting, human-computer dialogue, communication, self-test, thing
Therefore record and analysis report and debugging function.
The present invention is by external clamping high frequency ultrasound wave flowmeter under the premise of not destroying transformer existing structure integrality
It realizes and real-time measurement is carried out to conservator connecting tube interior oil stream.External clamping high frequency ultrasound wave flowmeter is independently of electric power networks, oil
Flow feature measurement and signal transmission be disturbed it is smaller, also not to electric system harmonic；Data acquisition element, oil stream fortune
It calculates analysis element and is fully able to meet the requirement for handling multi-path, high-frequency data quickly, in real time.Further, the present invention uses
Measurement frequency is 100Hz or more, and for measurement error less than 1%, operating temperature is -30~80 DEG C, and flow velocity range is -20~20m/s
Outer bundle type high frequency ultrasound wave flowmeter, no matter outer bundle type high frequency ultrasound wave flowmeter can meet from precision or use scope
Power transformer internal high temperature, greasy dirt, strong electromagnetic environmental requirement.
The present invention utilizes the transient changing feature of oil stream and the stream occurred at different operating conditions inside conservator connecting tube
The mechanical protection constituted by rule of thumb with feeling in the past is increased to quantitative by the different examination oil tank of transformer internal fault of speed difference
Analysis, high reliability determine, new stage of Digital Realization, to adapt to current and future large capacity, voltage levels electric power
Requirement of the transformer to protection " four property ", has no correlative study, report and product at home, outside.
Field test is carried out by test platform of SFSZ8-40000/110 three-phase three-winding transformer, illustrates effect of the present invention
Fruit, the main geometry of type transformer and nameplate parameter are as shown in table 1.As shown in figure 3, (the t when the transformer operates normally
< 0ms), there are not significant changes in installation for transformer connecting tube inside oil stream, the instantaneous velocity that present apparatus measurement at this time obtains
vmsLess than starting threshold vst, this protective device do not start.When transformer happens suddenly interior unit cell model at the t=0ms moment, due to
The injection of fault energy, failure gas generation lead to the raw directed flow of conservator connecting tube built-in electrical insulation fry dried food ingredients.When t=64.27ms,
The oil stream actuating quantity v that apparatus of the present invention operation result of measurement obtainsopGreater than protection deliberate action threshold value vth, this protective device at this time
It is determined as power transformer interior fault and issues trip signal, cuts off failure transformer.Fieldtesting results show: present invention dress
It sets, oil stream Characteristics of Mutation inside oil-immersed power transformer conservator connecting tube can be captured in a very short period of time, and pass through meter
The oil stream actuating quantity for obtaining to characterize inside transformer oil flow surge intensity is calculated, is compared according to default Protection criteria,
It is correct to screen inside transformer arc fault, it is reliable, sensitive, quickly cut off failure.
The main geometry of 1 SFSZ8-40000/110 type transformer of table and nameplate parameter
The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be said that
A specific embodiment of the invention is only limitted to this, for those of ordinary skill in the art to which the present invention belongs, is not taking off
Under the premise of from present inventive concept, several simple deduction or replace can also be made, all shall be regarded as belonging to the present invention by institute
Claims of submission determine scope of patent protection.
Claims (10)
1. a kind of digital gaseous shield of power transformer characterized by comprising transient state oil stream feature measurement mould
Block, switching input module, signal condition and acquisition module and digital core module；Wherein, transient state oil stream feature measurement
Module is connected with signal condition with acquisition module, signal condition and acquisition module and switching input module with digital core mould
Block is connected；
Transient state oil stream feature measurement module is special for transient state oil stream variation inside real time high-speed measuring transformer conservator connecting tube
Sign, and export corresponding analog voltage/current signal；Transient state oil stream feature measurement module is by outer bundle type high frequency ultrasound
Wave flowmeter, flowmeter transmitters and communications cable composition；
Signal condition and acquisition module are used to receive the analog voltage/current signal of transient state oil stream feature measurement module output,
And it is converted into the standardized digital signal that digital core module can identify, then outputting standard digital signal；
Switching input module is used to acquire the related switch amount signal for needing to know, and outputs it as high level 1 or low electricity
Flat 0, the input digital quantity as digital core module；
After digital core module is for receiving input digital quantity and standardized digital signal, protection operation is executed, digital signal is completed
Processing task, and then realize relay protection function.
2. the digital gaseous shield of a kind of power transformer according to claim 1, which is characterized in that outer bundle type is high
Frequency ultrasonic flowmeter is mounted in installation for transformer connecting tube, outer bundle type high frequency ultrasound wave flowmeter and flowmeter transmitters phase
Even, flowmeter transmitters are connected with the communications cable.
3. the digital gaseous shield of a kind of power transformer according to claim 2, which is characterized in that outer bundle type is high
The measurement frequency of frequency ultrasonic flowmeter is 100Hz or more, and measurement error is less than 1%, and operating temperature is -30~80 DEG C, flow velocity
Range is -20~20m/s.
4. the digital gaseous shield of a kind of power transformer according to claim 2, which is characterized in that signal condition
With acquisition module by connecting terminal, signal conditioning circuit, low-pass filter, signal sample circuit and modulus A/D conversion circuit
Composition；Connecting terminal is connected with signal conditioning circuit, and signal conditioning circuit is connected with low-pass filter, low-pass filter and signal
Sample circuit is connected, and signal sample circuit is connected with modulus A/D conversion circuit, modulus A/D conversion circuit and digital core module
It is connected；Connecting terminal is also connected with the communications cable.
5. the digital gaseous shield of a kind of power transformer according to claim 1, which is characterized in that digital core
Module is made of bus, central processing unit, timer/counter, random access memory, read-only memory and control circuit；Always
Line includes data/address bus, address bus and control bus, realizes data exchange and operation control；Central processing unit utilizes monolithic
Microprocessor, general purpose microprocessor or digital signal processor realize Digital Signal Processing；It is fixed that timer/counter is used to provide
When sampling trigger signal, formed interrupt, protection deferred action timing；Random access memory is for keeping in ephemeral data, including signal
Conditioning and the data information of acquisition module input, the intermediate result of calculation processes；It is read-only memory for saving data；Control
Circuit processed realizes the connection of entire digital circuit by Complex Programmable Logic Devices or field programmable gate array and coordinates work
Make.
6. the digital gaseous shield of a kind of power transformer according to claim 1, which is characterized in that further include with
Digital core module connected external communication interface module, human-computer dialogue module and switching value output module；
External communication interface module is to provide the information channel with computer communication network and telecommunicatio network；
Human-computer dialogue module is used for the informational linkage established between digital protection equipment and user；
Switching value output module controls the on-off for executing trip(ping) circuit for 0 or 1 state by output.
7. the digital gaseous shield of a kind of power transformer according to claim 6, which is characterized in that human-computer dialogue
Module includes compact keyboard, display screen, indicator light, button, printer interface and debugging communication interface；Switching value output module
It is made of photoelectric isolating device and exit relay, photoelectric isolating device is connected with exit relay.
8. a kind of protection side based on the digital gaseous shield of power transformer described in any one of claim 1-7
Method, which comprises the following steps:
1. transient state oil stream variation characteristic inside transient state oil stream feature measurement module real-time measurement installation for transformer connecting tube, and it is defeated
Corresponding analog voltage/current signal out；Signal condition and acquisition module receive transient state oil stream feature measurement module
The analog voltage/current signal of output, and it is converted into the standardized digital signal that digital core module can identify, then export
Standardized digital signal；After digital core module receives input digital quantity and standardized digital signal, temporary blocking defencive function is waited
There are the data of one or two cycle sampled data buffer area, then open and protection function；
2. more current t moment oil stream flow velocity vms(t) with starting threshold vstBetween amplitude size relation, that is, pass through judgement formula
(1) whether start at the digital protection of Rob Roy decision, if formula (1) is set up, 3. active flag set enters step；
vms(t)-vst≥0 (1)
3. calculating the oil stream actuating quantity v of current t moment using formula (2)op(t), compare oil stream actuating quantity vop(t) with protection threshold value
vthBetween amplitude size relation, that is, judge formula (3) whether at Rob Roy screen oil tank of transformer internal fault；If formula (3) is set up,
Trip signal is then issued, the whole series protection involution waits manual reset；
In formula (2), T is data window length, and f is the signal sampling frequencies of acquisition module；
vop(t)/kre≥vth (3)
In formula (3), kreTo protect safety factor；vthFor digital protection threshold value.
9. guard method according to claim 8, which is characterized in that in formula (1), start threshold vstFor 0.2~0.4m/s.
10. guard method according to claim 8, which is characterized in that in formula (3), protect safety factor kreIt is 1.2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910375867.8A CN110071481B (en) | 2019-05-07 | 2019-05-07 | Digital gas protection device and method for power transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910375867.8A CN110071481B (en) | 2019-05-07 | 2019-05-07 | Digital gas protection device and method for power transformer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110071481A true CN110071481A (en) | 2019-07-30 |
| CN110071481B CN110071481B (en) | 2021-08-13 |
Family
ID=67370142
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910375867.8A Active CN110071481B (en) | 2019-05-07 | 2019-05-07 | Digital gas protection device and method for power transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110071481B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020224536A1 (en) * | 2019-05-07 | 2020-11-12 | 北京中瑞和电气有限公司 | Transformer digital gas protection and oil flow surge monitoring integrated device and method |
| CN112928741A (en) * | 2021-02-08 | 2021-06-08 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Heavy gas protection locking method for tap switch based on oil pressure fluctuation of converter transformer |
| CN113078615A (en) * | 2021-02-25 | 2021-07-06 | 国电南瑞科技股份有限公司 | Active protection method and device for large power transformer |
| CN114661014A (en) * | 2022-04-27 | 2022-06-24 | 西安热工研究院有限公司 | Switching value control method and system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101551440A (en) * | 2009-05-15 | 2009-10-07 | 东北大学 | Generator transformer unit faults recorder analysis device |
| CN102810843A (en) * | 2011-06-02 | 2012-12-05 | 北京纳森新能源技术有限公司 | Protective measuring and monitoring device for box-type transformer of wind driven generator |
| US20140375463A1 (en) * | 2013-06-20 | 2014-12-25 | Siemens Aktiengesellschaft | Functional monitoring of an electrolytic gas sensor having three electrodes, and hazard alarm and gas measuring device |
| CN105301281A (en) * | 2014-05-28 | 2016-02-03 | 国网山西省电力公司电力科学研究院 | Monitoring method and device for flowing speed of transformer oil flow |
| CN206250017U (en) * | 2016-11-24 | 2017-06-13 | 中国西电电气股份有限公司 | A kind of transformer intelligent water cooler |
-
2019
- 2019-05-07 CN CN201910375867.8A patent/CN110071481B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101551440A (en) * | 2009-05-15 | 2009-10-07 | 东北大学 | Generator transformer unit faults recorder analysis device |
| CN102810843A (en) * | 2011-06-02 | 2012-12-05 | 北京纳森新能源技术有限公司 | Protective measuring and monitoring device for box-type transformer of wind driven generator |
| US20140375463A1 (en) * | 2013-06-20 | 2014-12-25 | Siemens Aktiengesellschaft | Functional monitoring of an electrolytic gas sensor having three electrodes, and hazard alarm and gas measuring device |
| CN105301281A (en) * | 2014-05-28 | 2016-02-03 | 国网山西省电力公司电力科学研究院 | Monitoring method and device for flowing speed of transformer oil flow |
| CN206250017U (en) * | 2016-11-24 | 2017-06-13 | 中国西电电气股份有限公司 | A kind of transformer intelligent water cooler |
Non-Patent Citations (1)
| Title |
|---|
| 闫晨光 等: "基于压力特征的变压器数字式保护研究", 《中国电机工程学报》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020224536A1 (en) * | 2019-05-07 | 2020-11-12 | 北京中瑞和电气有限公司 | Transformer digital gas protection and oil flow surge monitoring integrated device and method |
| CN112928741A (en) * | 2021-02-08 | 2021-06-08 | 中国南方电网有限责任公司超高压输电公司检修试验中心 | Heavy gas protection locking method for tap switch based on oil pressure fluctuation of converter transformer |
| CN113078615A (en) * | 2021-02-25 | 2021-07-06 | 国电南瑞科技股份有限公司 | Active protection method and device for large power transformer |
| CN113078615B (en) * | 2021-02-25 | 2022-11-22 | 国电南瑞科技股份有限公司 | Active protection method and device for large power transformer |
| CN114661014A (en) * | 2022-04-27 | 2022-06-24 | 西安热工研究院有限公司 | Switching value control method and system |
| CN114661014B (en) * | 2022-04-27 | 2023-07-25 | 西安热工研究院有限公司 | Switching value control method and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110071481B (en) | 2021-08-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110071481A (en) | A kind of digital gaseous shield of power transformer and method | |
| CN111784178B (en) | Distribution transformer state evaluation method based on multi-source information fusion | |
| CN110061473B (en) | Digital protection device and method for transformer based on pressure single quantity information | |
| CN110165778A (en) | A kind of oil-immersed power transformer non-ionizing energy loss fault wave recording device and method | |
| CN109980602B (en) | Digital self-adaptive protection device and method for transformer based on pressure characteristics | |
| CN104635128B (en) | Arc fault recognition capability analysis of experiments device and its test analysis method | |
| CN103234576A (en) | State monitoring system for power devices in intelligent substations | |
| CN103364641B (en) | A kind of transformer station's transient state electromagnetic environment test method | |
| CN110086257A (en) | The digital protection of transformer and oil flow surge monitoring integration device and method | |
| CN107884645A (en) | Based on voltage ratio compared with power capacitor method for monitoring operation states | |
| CN104181427A (en) | Online monitoring system of intelligent substation transformer | |
| CN106410739A (en) | Arc protection device and fault diagnosis method thereof | |
| CN103884953A (en) | Damping loop fault diagnosis system of capacitor voltage transformer | |
| CN203164360U (en) | Transformer device insulation online monitoring system | |
| CN105634123A (en) | Automatic low-voltage circuit breaker control apparatus with remote monitoring function and application therefor | |
| CN107703406A (en) | A kind of power transformer iron core grounding monitor method and system | |
| CN110112706B (en) | Transformer digital protection device and method based on pressure full information | |
| CN102983550B (en) | Transformer interturn short circuit protection method based on current ratio variable quantity | |
| CN110161357A (en) | A kind of oil-immersed power transformer pressure relief valve fault wave recording device and method | |
| Jia et al. | Research on characteristics and calibration method of gas relay of power transformer in power grid | |
| CN204947719U (en) | A kind of automatic low-voltage circuit breaker control device with remote monitoring function | |
| CN110231523A (en) | A kind of oil-immersed power transformer protection fault wave recording device and method | |
| CN203849352U (en) | Apparatus for diagnosing fault of damping loop of capacitor voltage transformer | |
| CN112151337B (en) | Circuit breaker with at least two poles | |
| CN109600116B (en) | Movable photovoltaic grid-connected detection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |