CN107069805A - Wind power plant black starting-up system - Google Patents
Wind power plant black starting-up system Download PDFInfo
- Publication number
- CN107069805A CN107069805A CN201710172640.4A CN201710172640A CN107069805A CN 107069805 A CN107069805 A CN 107069805A CN 201710172640 A CN201710172640 A CN 201710172640A CN 107069805 A CN107069805 A CN 107069805A
- Authority
- CN
- China
- Prior art keywords
- module
- power plant
- wind power
- starting
- black starting
- 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
- 238000012545 processing Methods 0.000 claims abstract description 37
- 238000004891 communication Methods 0.000 claims abstract description 13
- 238000006243 chemical reaction Methods 0.000 claims abstract description 11
- 238000012544 monitoring process Methods 0.000 claims description 6
- 230000008859 change Effects 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 3
- 238000012546 transfer Methods 0.000 claims description 2
- 238000004088 simulation Methods 0.000 claims 1
- 230000007257 malfunction Effects 0.000 abstract description 5
- 238000005070 sampling Methods 0.000 abstract description 5
- 230000005856 abnormality Effects 0.000 abstract description 3
- 238000011161 development Methods 0.000 abstract description 2
- 230000009471 action Effects 0.000 description 10
- 238000012360 testing method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 230000005611 electricity Effects 0.000 description 5
- 238000012986 modification Methods 0.000 description 5
- 230000004048 modification Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 238000002955 isolation Methods 0.000 description 4
- 230000003993 interaction Effects 0.000 description 3
- 238000011017 operating method Methods 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000008034 disappearance Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000009897 systematic effect Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
-
- H02J3/386—
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
Abstract
A kind of wind power plant black starting-up system include power module, exchange conversion module, ac filter module, central processing system, Communication processing module, open into optically isolated module, central signal and starting module, outlet output module, man-machine interface processing module, backboard.The need for the wind power plant black starting-up system of the present invention has stronger adaptability, open and scalability, requirement and the power network development to adapt to difference in functionality；The system, which has, perfect prevents the functions such as measures, the abnormality alarming of malfunction and tripping, very strong interference free performance, it is ensured that the reliability of system acting；Host CPU uses 32 bit processing machines and multiple FPGA High speed logic chips of multi-disc ARM9 frameworks in simultaneity factor so that its speed faster, uses 16 A/D conversion chips on hardware, not only sampling precision is improved, sample rate is also faster, and with mass-memory unit, can record mass data.
Description
Technical field
The present invention relates to new energy wind power generation field, it particularly relates to the black starting-up system of wind power plant.
Background technology
With continuing to develop for Power System Interconnection and remote conveying power technology, large sized unit, extra-high tension unit, power electronics
Device and distributed generation technology etc. are largely introduced in power system, add expanding day by day for power system scale, system
Dynamic behaviour becomes to become increasingly complex, and service condition requires harsher, is more difficult to prediction, considerably increases and is triggered by local fault
The risk of electric power disaster.Under power network occurrence of large-area power-off condition, it is desirable to can quick-recovery power supply soon, if can not be short
Restored electricity within time, national economy will be made to take a bath.
After black starting-up (Black Start) refers to whole system because of fault outage, independent of other system help, by being
The startup with self-startup ability unit drives the unit of non self starting in system, gradually expands system power supply scope, finally
Realize the process that whole system is recovered.
The background of black starting-up is that system all has a power failure or large-area power-cuts, i.e. system are in major accident state, black starting-up
Process is a kind of extreme case of recovery process, it will be related in system operation generate electricity, the links of transmission and disttrbution.
How safety and system reconstructing is quickly completed after system large-area power-cuts, be all that power industry is urgently to be resolved hurrily all the time
Key issue, therefore, the research of black starting-up technology recovers to have great importance for the system under extreme case.
Wind-power electricity generation is as the recyclable new energy of cleaning, and China is actively promoting its application always.Cut-off 2014 12
Month, the wind-power electricity generation total amount of China reaches 62,730,000 kilowatts, ranked the first；2nd, 3 are 46,910,000 kilowatts of the U.S. and Germany respectively
29910000 kilowatts.Therefore the black starting-up system of research wind power plant has great importance for the environment and economy of China.
The content of the invention
Goal of the invention：Whether the technical problem to be solved in the present invention is, it is necessary to can to output of wind electric field during black starting-up
Meet its estimated as black starting-up Power Supplies Condition, during black starting-up important node electric voltage frequency and amplitude fluctuation whether
Be monitored beyond stability range, carry out extensive and high-frequency Load flow calculation, each power supply is exerted oneself to be scheduled, into
Hundred thousands of breakers carry out breaker tripping and closing operation.
Technical scheme：A kind of wind power plant black starting-up system, the system includes power module, exchange conversion module, exchange filter
Ripple module, central processing system, Communication processing module, open into optically isolated module, central signal and starting module, outlet output mould
Block, man-machine interface processing module, backboard, the power module are used for the 220/110V voltage for being converted into+5V ,+24V, give
Other module for power supply；The exchange conversion is used for the voltage signal being transformed into ac analog in AD input ranges, exchange filter
Ripple module is used to handle analog quantity；The central processing system receives ac filter module, Communications Processor Module and opened
Enter the data and information of optically isolated module transfer；The Communications Processor Module is used to realize that system and the data of the monitoring day after tomorrow are handed over
Change；Described open into optically isolated plug-in unit is opened into the central signal and starting module are to complete central signal to input light current
Output and enabling signal output function；Outlet output inserter is used for the output function for completing signal；At the man-machine interface
Managing module is used for interacting between people and machine, and backboard is connected to each functional module.
Further, the processing that the ac filter module is carried out to analog quantity includes filtering out high-frequency signal, level adjustment.
Further, the man-machine interface processing module includes touch-screen, keyboard, status indicator lamp and debugging mouth.
Further, the central processing system includes multi-disc ARM frameworks and multiple FPGA High speed logic chips.
Beneficial effect：
Wind power plant black starting-up system has stronger adaptability, open and scalability, to adapt to wanting for difference in functionality
The need for summation power network development；The system have it is perfect prevent the functions such as measures, the abnormality alarming of malfunction and tripping, very
Strong interference free performance, it is ensured that the reliability of action；In simultaneity factor host CPU using multi-disc ARM9 frameworks 32 bit processing machines and
Multiple FPGA High speed logic chips so that faster, using 16 A/D conversion chips on hardware, not only sampling precision is carried its speed
Height, sample rate is also faster, and with mass-memory unit, can record mass data.
Brief description of the drawings
Fig. 1 is system construction drawing；
Fig. 2 is exchange conversion module principle figure；
Fig. 3 is the system diagram of scheme 1；
Fig. 4 is the system diagram of scheme 2.
Embodiment
The present invention is further described below in conjunction with the accompanying drawings.
The wind power plant black starting-up TT＆C system of the present invention is used for permanent magnet direct-driven Wind turbines and showed as the black starting-up of power supply
Test monitoring, control and protect, the system, and can by collection voltages, electric current, frequency, local circuit breaker position quantity of state
Communicated with remote device, obtain Wind turbines work state information auxiliary itself and complete wind power plant black starting-up.
The present invention a kind of wind power plant black starting-up system, including power module, exchange conversion module, ac filter module,
Central processing system, Communication processing module, open into optically isolated module, central signal and starting module, outlet output module, man-machine
Interface processing module, backboard, the power module are used for the 220/110V voltage for being converted into+5V ,+24V, give other modules
Power supply；The exchange conversion is used for the voltage signal being transformed into ac analog in AD input ranges, and ac filter module is used
The tunnel analog quantitys of Yu Dui 12 are handled；The central processing system receives ac filter module, Communications Processor Module and opened into light
The data and information of isolation module transmission；The Communications Processor Module is used for the data exchange for realizing system and the monitoring day after tomorrow；Institute
State to open into optically isolated plug-in unit and opened to input light current into the output of the central signal and starting module to complete central signal
With the output function of enabling signal；Outlet output inserter is used for the output function for completing signal；The man-machine interface processing module
For interacting between people and machine, backboard is connected to each functional module.
Each functions of modules is described as follows：
1) power module
Power insert by external dc 220/110V power supplys through it is anti-interference electricity, power switch to internal DC/DC converters, it is defeated
Go out+5V ,+24V relay power gives other module for power supply by backboard, 24V power supplys are drawn additionally by back connection terminal,
When isolating with internal 24V for pulse pair.
2) exchange conversion module
12 road industrial frequency AC analog quantitys, voltage or current signal can at most be transformed into AD input ranges by the module
Voltage signal, voltage and current can be in any combination.For control source loop, anti-interference capacitor and magnetic are specially added
Ring, improves antijamming capability.
Because the PT and CT on exchange head can be with arbitrary dispositions, PT and CT number is not quite similar in Practical Project, position
Also it is incomplete same, therefore the external cabling of this module do not fix, with reference to concrete engineering drawing.
3) ac filter module
This module can be handled 12 tunnel analog quantitys, and its main function is：
A. high-frequency signal is filtered out；
B. level is adjusted；
C.AD samples；
D. calculating current, voltage effective value；
E. active power, reactive power, power-factor angle, phase angle are calculated；
F. recording.
This module is communicated by 2 road RS485 with center processing plug-in unit.
4) central processing system
Receive ac filter module, Communication processing module and open the data and information sent in module, synthesis is opened into grade letter
Breath, logic judgment determines central signal and trip signal and sends trip signal to give outlet mold part.By 2 tunnel optical-fibre channels, with
System swapping data, man-machine interface and monitoring system data are exchanged with Communication processing module, by externally debugging minUSB mouthfuls,
Logic testing and software download can be carried out.Simultaneously also 1 road pair when RS485 interfaces, opened during 1 road high-speed pulse pair into.
5) Communications Processor Module
This module has 3 road isolation RS 485s, 2 tunnels isolation RS232,2 road 10M/100M Ethernet RJ45 interfaces, 1 pair of investigation mission outside the city or town
MiniUSB mouthfuls of examination, interface at 1 pair standby GPS pairs.It is main to realize system and the data exchange of background monitoring, the work(such as print control
Can, while being also the bridge between human-computer interaction module and central processing module.
6) open into optically isolated module
This module uses CPLD and MCU.By CPLD, complete 20 road 24V light current of input and open into 2 tunnel one directions of output
RS485, gives the function of central processing module, and CAN and central processing module enter line number to MCU by 1 road RS485 and all the way simultaneously
According to exchange, checking and the self checking of plate level.
7) central signal and starting module
By CPLD, and central processing module output 2 tunnel one direction RS485, the output of 4 road central signals is completed, often
Road provides the function of the output of two pairs of idle contacts and 1 tunnel enabling signal, MCU simultaneously by 1 road RS485 and all the way CAN with it is central
Processing module carries out data exchange, checking and the self checking of plate level.
8) output module is exported
By CPLD, and central processing module output 2 tunnel one direction RS485, the work(that the output of signal is outputed on 5 roads is completed
Can, it is activated control positive supply, MCU by 1 road RS485 and all the way CAN and central processing module progress data exchange simultaneously are tested
The self checking of card and plate level.
9) man-machine interface processing module
Man-machine interface handles plug-in unit, mainly by touch-screen, keyboard and status indicator lamp and a few part compositions of debugging mouth, convenient
Interaction between people and machine.
10) backboard
Backboard is connected to each feature card, is the bridge between each module.
Present system definite value includes device parameter, controls definite value, exports configuration.Wherein systematic parameter definite value only has 1
Set, control definite value and outlet configuration tool can again be adjusted by possessing the user of authority by touch-screen.
System carries out man-machine interaction with menu mode by the liquid crystal of front panel, shows the survey of system in local operation
Measure result, definite value, logout, data record, action situation etc..Automatically into main menu after system is powered up or reset, directly
Touch HMI screen and complete operation.Fixed value modification is operated, and clicking on definite value in interface of main menu is set, and is needed to change fixed according to experiment
Value, checks whether fixed value modification is correct, after modification is finished, and returns to experiment menu.Black startup test, the examination of wind power plant black starting-up
Test and be divided into two kinds of automatic mode and manual mode.No matter which kind of test model, it is necessary to first according to testing program complete external cabling,
Fixed value adjusting.Under automatic mode, startup is clicked directly on.Operated under manual mode according to testing program.Event or number
Operated according to record queries, the action event and action recorder data of system record are that power down is not lost, can be at any time
It is queried.Have recorded the absolute time of system acting in logout, relative time, type of action, during action each analog quantity and
The data of switching value.
The system, which will be taken safety and stability control device, perfect prevents measures, the abnormality alarming of malfunction and tripping
Etc. function, very strong interference free performance, it is ensured that the reliability of device action.
A) capacitor-decoupling circuit is all used for the power connection part between each feature board in common-battery source；
B) prevent impulse disturbances from entering the influence of microcomputer loop or higher hamonic wave to correctness of sampling, except in ac input end
Plus outside anti-interference terminal, the AC analogue input circuit of system is equipped with LPF loop, and the high order for filtering out more than three times is humorous
Wave component；
C) to prevent input circuit and sampling circuit from malfunctioning, in addition to using redundancy processing on software, also using physical quantity
Result of calculation, such as power are total) proofreaded.Software has home loop self-diagnostic function simultaneously, when home loop failure,
Effectively locking it can export；
D) judgement and decision-making of any failure all use multiple different conditions, and multiple locking or two from three voting mechanism are determined
Determine the action behavior of system, effectively prevent malfunction；
E) hardware locking measure is used, is completely independent starting relay and exit relay, and constitute logical "and"
Relation.When breaking down, only open exit relay locking after starting relay action effectively prevents malfunction；
F) there is quick self-resetting bit function, if running into strong jamming makes CPU " walking dead ", hardware self-resetting circuit can guarantee that
CPU recovers normal operation completely within 10ms, and judgement and decision-making to accident have little to no effect；
G) all switching values introduced beyond system, first pass through the relay isolation of 110V/220V direct current forceful electric power loop,
Microcomputer loop, i.e. dual resisteance measure are just inputted after Phototube Coupling again；
H) the outlet action circuit of system is kept and electric current guard relay equipped with magnetic；
I) there is the alarm functions such as PT broken strings, CT open circuits, direct current disappearance, channel abnormal, self-inspection exception；
Energy automatic blocking outlet when j) setting definite value, carries out that correct password just effective, Ke Yiyou must be inputted during self-inspection
Effect prevents maloperation；
K) various simulated tests and anti-interference test are carried out before dispatching from the factory；
Three-phase alternating voltage U of the system to inputA、UB、UCWith three-phase alternating current IA、IB、ICSampled, sampling week
Phase is 0.833ms, i.e., one power frequency period is sampled 24 points.Frequency change rate is continuously entered using 100ms cycle (data window)
OK；Voltage change ratio uses 40ms cycle (data window).Formula is as follows：
dU/dt≌10·[Uk- U(k-0.04”)] %UN/s
df/dt≌10·[fk- f(k-0.1”)] Hz/s
Three phases active power is calculated again
By 90 degree of voltage phase shift in above-mentioned calculating active power formula, then idle algorithm is：
The system operation criterion mainly has basic electrical quantity, killer switch amount and operating states of the units totally 3 aspects.
When each step of operation progress judges, electrical quantity (voltage, electric current, frequency, power), which need to be met, presets rated value under respective step
During percentage, it is believed that electrical quantity criterion is qualified under the step.Each operation is performed, to all breakers, presetting needs what is closed
Breaker closing, the breaker for being not belonging to default closure disconnects, it is believed that circuit-breaker status criterion is qualified under the step.Similarly, exist
Under each execution step, the criterion of operating states of the units is also uniquely to meet.Only simultaneously when above-mentioned 3 criterions are met,
The step can be performed.
The present invention gives specific two schemes, Tables 1 and 2 is respectively the system diagram of scheme 1 and scheme 2, table 1 it is specific
Operating procedure corresponding diagram 3, the concrete operation step corresponding diagram 4 of table 2.
The operating procedure of 1 scheme of table 1
To prevent from causing misoperation under the abnormal conditions such as excitation surge current, higher hamonic wave, resonance, it can take and take following as follows
Scheme 2, starting step is as shown in Table.
The operating procedure of 2 scheme of table 2
Described above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications also should
It is considered as protection scope of the present invention.
Claims (4)
1. a kind of wind power plant black starting-up system, it is characterised in that the system includes power module, exchange conversion module, exchange filter
Ripple module, central processing system, Communication processing module, open into optically isolated module, central signal and starting module, outlet output mould
Block, man-machine interface processing module, backboard, the power module are used for the 220/110V voltage for being converted into+5V ,+24V, give
Other module for power supply；The exchange conversion is used for the voltage signal being transformed into ac analog in AD input ranges, exchange filter
Ripple module is used to handle analog quantity；The central processing system receives ac filter module, Communications Processor Module and opened
Enter the data and information of optically isolated module transfer；The Communications Processor Module is used to realize that system and the data of the monitoring day after tomorrow are handed over
Change；Described open into optically isolated plug-in unit is opened into the central signal and starting module are to complete central signal to input light current
Output and enabling signal output function；Outlet output inserter is used for the output function for completing signal；At the man-machine interface
Managing module is used for interacting between people and machine, and backboard is connected to each functional module.
2. a kind of wind power plant black starting-up system as claimed in claim 1, it is characterised in that the ac filter module is to simulation
The processing that amount is carried out includes filtering out high-frequency signal, level adjustment.
3. a kind of wind power plant black starting-up system as claimed in claim 1, it is characterised in that the man-machine interface processing module bag
Include touch-screen, keyboard, status indicator lamp and debugging mouth.
4. a kind of wind power plant black starting-up system as claimed in claim 1, it is characterised in that the central processing system includes many
Piece ARM frameworks and multiple FPGA High speed logic chips.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710172640.4A CN107069805A (en) | 2017-03-21 | 2017-03-21 | Wind power plant black starting-up system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710172640.4A CN107069805A (en) | 2017-03-21 | 2017-03-21 | Wind power plant black starting-up system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107069805A true CN107069805A (en) | 2017-08-18 |
Family
ID=59620814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710172640.4A Pending CN107069805A (en) | 2017-03-21 | 2017-03-21 | Wind power plant black starting-up system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107069805A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109193951A (en) * | 2018-11-08 | 2019-01-11 | 南京国电南自维美德自动化有限公司 | A kind of intelligent operation box with surge suppression function |
| CN110165704A (en) * | 2019-05-29 | 2019-08-23 | 华润协鑫(北京)热电有限公司 | A kind of black-start method of power grid |
| US11434871B2 (en) | 2018-01-25 | 2022-09-06 | Vestas Wind Systems A/S | Black start restoration |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105633960A (en) * | 2016-03-09 | 2016-06-01 | 东南大学 | Multi-adaptive black-start apparatus |
-
2017
- 2017-03-21 CN CN201710172640.4A patent/CN107069805A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105633960A (en) * | 2016-03-09 | 2016-06-01 | 东南大学 | Multi-adaptive black-start apparatus |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11434871B2 (en) | 2018-01-25 | 2022-09-06 | Vestas Wind Systems A/S | Black start restoration |
| TWI791745B (en) * | 2018-01-25 | 2023-02-11 | 丹麥商維斯塔斯風力系統有限公司 | Method and system for performing black start operations, and wind turbine |
| CN109193951A (en) * | 2018-11-08 | 2019-01-11 | 南京国电南自维美德自动化有限公司 | A kind of intelligent operation box with surge suppression function |
| CN110165704A (en) * | 2019-05-29 | 2019-08-23 | 华润协鑫(北京)热电有限公司 | A kind of black-start method of power grid |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101777785B (en) | Uninterrupted power supply (UPS) electricity separating system and electricity separating method based on dynamic environment monitoring | |
| CN202948040U (en) | Intelligent electric energy meter having power failure monitoring and protection functions | |
| CN102842887B (en) | Anti-interference electricity protection method and anti-interference electricity protection device for electric equipment | |
| CN107069805A (en) | Wind power plant black starting-up system | |
| CN102437650A (en) | Intelligent electric power distribution system | |
| CN104779705A (en) | Line protection measurement and control method and device | |
| CN102590698B (en) | Small current grounding line selection device and control method of voltage disturbance locked line selection | |
| CN202475013U (en) | Intelligent power distribution device | |
| CN102290803B (en) | Micro-grid relaying protection method and device | |
| CN201278463Y (en) | Digital bus connection protection apparatus | |
| CN115498774B (en) | Microcomputer type distribution automation station terminal based on multi-line measurement and control | |
| CN205178643U (en) | Integrated device is observed and controled in protection | |
| CN203149045U (en) | Spare power supply auto-switching calibrator | |
| CN202260419U (en) | Digital type bus-bar protection device | |
| CN201860126U (en) | Monitoring protection comprehensive device of low voltage unit | |
| CN104022493A (en) | Portable temporary protection device for 220KV circuit | |
| CN201278459Y (en) | Digital transformer protection apparatus | |
| CN104901415B (en) | Dual power supply central control device | |
| CN109600116B (en) | Movable photovoltaic grid-connected detection system | |
| CN201260072Y (en) | Digital motor protection device | |
| CN112952984A (en) | Host, device and method for spare power automatic switching | |
| CN2569404Y (en) | Low voltage motor protective monitor for microprocessor | |
| CN207397088U (en) | A kind of universal protection supervisory equipment | |
| CN201260069Y (en) | Digital line protective device | |
| Bright et al. | Integrated monitoring, protection, and control systems for industrial and commercial power systems |
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 | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20170818 |