CN207588441U - The judgment means of overvoltage in a kind of power grid - Google Patents
The judgment means of overvoltage in a kind of power grid Download PDFInfo
- Publication number
- CN207588441U CN207588441U CN201721628672.2U CN201721628672U CN207588441U CN 207588441 U CN207588441 U CN 207588441U CN 201721628672 U CN201721628672 U CN 201721628672U CN 207588441 U CN207588441 U CN 207588441U
- Authority
- CN
- China
- Prior art keywords
- measuring apparatus
- overvoltage
- control unit
- power grid
- described control
- 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.)
- Active
Links
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model discloses a kind of judgment means of overvoltage in power grid, include the earthed circuit of control unit, measuring apparatus, three phase network and three phase network ground connection, the measuring apparatus includes the first measuring apparatus, the second measuring apparatus, third measuring apparatus and the 4th measuring apparatus that are respectively arranged in the three phase network and earthed circuit；The current acquisition unit of detection measuring apparatus electric current is separately provided in first measuring apparatus, the second measuring apparatus, third measuring apparatus and the 4th measuring apparatus；The current acquisition unit is connect respectively with described control unit；Described control unit is used to compare the current value of current acquisition unit, and is judged.The utility model is simple in structure, and judgment mode is simple.
Description
Technical field
The utility model belongs to overvoltage judgment technology field in power grid, and in particular to the judgement of overvoltage in a kind of power grid
Device.
Background technology
At present, in the market overvoltage protection type is various, and multifarious, effect is undesirable, and function is not
Safe operation of electric network requirement can be met.
Overvoltage protection of the prior art, for the overvoltage such as switching overvoltage, resonance mistake of different types
There is the missing inspection from Microcomputer Protection, false retrieval, flase drop and leakage in voltage, single-phase intermittent arc earthing overvoltage, lightning surge etc.
The hidden danger such as report, misrepresent deliberately, reporting by mistake.
Meanwhile in the prior art, it is to judge for a long time, is determined as overvoltage phenomenon.This prolonged data judgement,
Time-consuming, meanwhile, find overvoltage evening, use is very inconvenient.
Invention content
The technical problem to be solved by the present invention is to provide a kind of judgment step it is few, take it is short, for the mistake in power grid
The judgment method and device of voltage.
In order to achieve the above objectives, the technical solution of the utility model is as follows：
The judgment means of overvoltage in a kind of power grid, including control unit, measuring apparatus, three phase network and three phase network
The earthed circuit of ground connection, the first measurement that the measuring apparatus includes being respectively arranged in the three phase network and earthed circuit are set
Standby, the second measuring apparatus, third measuring apparatus and the 4th measuring apparatus；First measuring apparatus, the second measuring apparatus, third
The current acquisition unit of detection measuring apparatus electric current is separately provided in measuring apparatus and the 4th measuring apparatus；The electric current
Collecting unit is connect respectively with described control unit；Described control unit is used to compare the current value of current acquisition unit, goes forward side by side
Row judges.
Further, the measuring apparatus is prepared by non-damping material.
Further, described control unit is connect with the current acquisition unit by isolating device.
Further, the isolating device includes the electricity being sequentially connected in series between current acquisition unit and described control unit
Resistance, diode rectifier bridge and capacitance, the resistance, diode rectifier bridge and capacitance are connect respectively with described control unit.
Further, described control unit is set in housing, and display device, interface, report are respectively equipped on the housing
Alert device and indicator light, described control unit are connect respectively with the display device, interface, alarm and indicator light.
Further, described control unit is also associated with module at GPS pairs.
Through the above technical solutions, the beneficial effects of the utility model are：
In the utility model, by acquiring the electric current passed through in electric current rather than circuit in measuring apparatus, measuring method
Simply, compared with deciding whether as overvoltage again after existing long-time judges, step is succinct, and speed is faster.
The utility model compared with prior art, solves in the prior art, it is impossible to the problem of judging instantaneous overvoltage, it is real
Real time monitoring is showed and has judged.
In the utility model, pass through the electric current of measuring apparatus leakage, you can judge whether there is overvoltage, solve
The overvoltage of different types（Such as switching overvoltage, resonance overvoltage, single-phase intermittent arc earthing overvoltage, thunder and lightning mistake
Voltage etc.）Decision problem, fundamentally solve the missing inspection of previous Microcomputer Protection, false retrieval, flase drop and fail to report, misrepresent deliberately, report by mistake
Etc. hidden danger.It can not only monitor and can be uploaded to backstage on the spot concentrates inspection, effectively raises the safety coefficient of power grid, and
Power station staff can be reminded in time, is taken the necessary measures, prevents the generation of all kinds of Overvoltages, protected for electric power netting safe running
Drive convoy.
The judgment means of power network overvoltage in the utility model, can integral installation and dismounting, convenient for safeguard.Equipped with number
Formula instrument and electrification indicator light, facilitate staff's monitoring arrangement operating condition, device should be able to realize failure by acoustic optical devices
It alerts and records overvoltage action frequency.
For capacity current in the distribution network system of 100A, single-phase intermittent arc earthing event is occurring for the utility model
During barrier, effectively inhibit the generation of normal phase harmfulness overvoltage.
The utility model can monitor the operating status of power grid in real time, and the size of leakage current during overpressure situation occurs in display,
Failure phase when indicating that single-phase arc grounding failure occurs, and sound-light alarm is carried out, record overvoltage protection action frequency.
Description of the drawings
It in order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only
It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor
Under, it can also be obtained according to these attached drawings other attached drawings.
Fig. 1 is a kind of circuit diagram of electric network protection monitoring device provided by the utility model；
Fig. 2 is the circuit diagram of signal picker provided by the utility model；
Fig. 3 is a kind of circuit diagram of electric network protection monitoring device provided by the utility model；
Fig. 4 is the structure diagram of housing provided by the utility model；
Fig. 5 is the having a rest property arc grounding current recording of the monitoring device of electric network protection in the prior art provided by the utility model
Figure；
Fig. 6 is the having a rest property arc grounding current recording of the judgment means of overvoltage in a kind of power grid provided by the utility model
Figure；
In figure：
1st, the first measuring apparatus；2nd, the second measuring apparatus；3rd, third measuring apparatus；4th, the 4th measuring apparatus；5th, control is single
Member；6th, current acquisition unit；7th, isolating device；701st, resistance；702nd, diode rectifier bridge；703rd, capacitance；9th, housing；10th, it shows
Showing device；11st, interface；12nd, alarm；13rd, indicator light；14th, GPS pairs when module；16th, twin-core shielding line；17th, aviation socket；
18th, power grid；19th, shunt resistance.
Specific embodiment
In order to be easy to understand technical means, creative features, achievable purpose and effectiveness of the utility model, under
Face combines and is specifically illustrating, and the utility model is expanded on further.
With reference to shown in attached drawing 1-6, the judgment method of overvoltage, is mainly used in a kind of power grid 18 provided by the utility model
With national grid 18 when judgement when occurring with the overvoltage in three-phase circuit connecting, wherein, three-phase
The circuit that A.C.circuit is powered by three-phase alternating-current supply.Abbreviation three-phase circuit.Three-phase alternating-current supply refers to provide 3 frequencies
Rate is identical and voltage or the power supply of electric current that phase is different, and the most commonly used is threephase alternators.Each phase of threephase generator
120 ° of the phase mutual deviation of voltage.Each phase voltage is in advance between them or the order of lag is known as phase sequence.Threephase motor is in positive sequence
It is rotated forward during power voltage supply, is changed to then invert during negative sequence voltage power supply.It must be noted that its phase sequence when therefore, using three phase mains.One
A little production equipments for needing rotating can power phase sequence to control the rotating of threephase motor by change.Three-phase circuit is one
The special alternating current circuit of kind, is made of three phase mains, threephase load and three phase line.Electric system electrical energy production in the world
Power supply mode mostly uses three-phase system.
The judgment method of the utility model, specifically includes following steps：
The setting of measuring apparatus：Setting measures three phase informations and ground connection in real time respectively in three-phase circuit and earthed circuit
The measuring apparatus of circuit information, respectively the first measuring apparatus 1, the second measuring apparatus 2, third measuring apparatus 3 and the 4th measure
Equipment 4；Wherein, the first measuring apparatus 1, the second measuring apparatus 2 and third measuring apparatus 3 are respectively used to measure every in three-phase circuit
The data information of phase, the 4th measuring apparatus 4 are used to measure the data acquisition in earthed circuit.
Data acquire：Acquisition is by first measuring apparatus 1 respectively, the second measuring apparatus 2, third measuring apparatus 3 and the
Electric current in four measuring apparatus 4, specific use obtain Ia, Ib, Ic and Io；Compared with prior art, the utility model passes through inspection
The electric current passed through in measuring apparatus is surveyed, variability is more sensitive, meanwhile, the current value measured is relatively small, more pacifies
Entirely.Compared with the electric current passed through in other direct measuring circuits, use, more securely and reliably.
The judgement of overvoltage：According to the comparison of the same time numerical value of Ia, Ib, Ic and Io, determine whether that overvoltage shows
As.
Specifically, the judgement of overvoltage phenomenon and the judgement of overvoltage type be：
Then it is Lightning Over-voltage as Io≤1A；
Work as 16mA<Io<1A, and be then list when the electric current same time of at least two is more than 10mA in Ia, Ib and Ic
Phase grounding surge；
Then it is behaviour when the electric current same time of at least two is more than 50mA as Io≤16mA, and in Ia, Ib and Ic
Work/retention overvoltage.
Specifically, the measuring apparatus is current measure device or voltage measuring apparatus.
More specifically, after the data collection steps, data isolation step is further included.
The utility model discloses a kind of judgment means of overvoltage in power grid 18, including control unit 5, measuring apparatus,
The earthed circuit that three phase network 18 and three phase network 18 are grounded, the measuring apparatus include being respectively arranged on the three phase network 18
And the first measuring apparatus 1, the second measuring apparatus 2,3 and the 4th measuring apparatus 4 of third measuring apparatus in earthed circuit；Wherein,
First measuring apparatus 1, the second measuring apparatus 2 are separately provided for detecting in 3 and the 4th measuring apparatus 4 of third measuring apparatus
The current acquisition unit 6 of measuring apparatus electric current；The current acquisition unit 6 is four, and four current acquisition units 6 are respectively with the
One measuring apparatus 1, the second measuring apparatus 2,3 and the 4th measuring apparatus 4 of third measuring apparatus connect.Four current acquisition lists
Member 6 is connect respectively with described control unit 5；Described control unit 5 is used to compare the current value of current acquisition unit, and is sentenced
It is disconnected.
In the utility model, the measuring apparatus is prepared by non-damping material.
In the utility model, employ special material, non-damper assembly, from source solve common copper, zinc, chromium,
The problem of technology requirement is not achieved in the materials such as nickel（Measuring unit of the prior art is mostly the materials such as copper, zinc, chromium, nickel）.Its
In, non-damper assembly is a kind of special material, its feature, structure, and parameter etc. and the materials such as existing copper zinc chrome nickel have this
The difference of matter, it is the nonlinear wind vibration using non-damper assembly, under the action of voltage, plays the role of aerial drainage.
Non- damper assembly in the utility model can effectively solve the various overvoltage problems in 18 field of power distribution network, prevent
The generation of single-phase intermittence arc grounding over-voltage damps climbing and amplitude that simultaneously transient suppression restores voltage, prevents
Cut-off overvoltage；Its energy effective damping simultaneously inhibits resonance overvoltage between phase and phase to be reached with switching overvoltage using material property
To protection purpose.
Non- damper assembly can substitute arc suppression coil, grounding transformer, overvoltage protection cabinet in 18 system of power grid completely
（Device）, the devices such as arrester, and overcome the principle defect of above device, the application of product can make the fortune of power distribution network 18
One class of row security improvement.
In order to realize the isolation of data in the transmission, in the utility model, control unit 5 and current acquisition unit 6 it
Between set isolating device 7.
Further, isolating device 7 includes being sequentially connected in series between current acquisition unit 4 and described control unit 5
Resistance 701, diode rectifier bridge 702 and capacitance 703, the resistance 701, diode rectifier bridge 702 and capacitance 703 respectively with institute
Control unit 5 is stated to connect.At this point, the purpose of resistance 701 is current limliting, increases and directly react；And diode rectifier bridge 702 is exchange
Electricity becomes direct current, i.e., using the unilateral conduction of diode, the convert alternating current of direction alternately variation into single direction
Rectified alternating current.The effect of shunt capacitance 703 is exactly to filter, that is, is exactly to be acted on using the charge and discharge of capacitance, becomes output voltage
Smoothly, i.e., AC compounent is filtered, it is only DC voltage to make output voltage.By isolating device 7, the data of acquisition are done whole
Stream, filtering, etc. processing, be sent to control unit 5 with by data such as waveforms, convenient for breakdown judge use.
Further, pressure regulator can also be increased on power grid 18, pressure regulator is used to adjust the voltage exported in power grid 18
Size.For the ease of detecting different size of voltage, embodiment adds pressure regulators.
In the utility model, control unit 5 is set in housing 9, while display device is respectively equipped on housing 9
10th, interface 11, alarm 12 and indicator light 13, control unit 5 respectively with the display device 10, interface 11, alarm 12 and
Indicator light 13 connects.
In use, when having measured overvoltage phenomenon, the size of Leakage Current, report can be shown by display device 10
Alert device 12 is for alarming, and indicator light 13 is also alarm function.
Further, the control unit of the utility model is also associated with module 14 at GPS pairs.
During due to electric current by preparing the nonlinear dampling material in measuring apparatus, most electric current can be through oversampling circuit stream
Go out, and sub-fraction, it can be leaked in equipment, after testing the size of this part of Leakage Current, and then judge whether had
The generation of voltage phenomenon.
With traditional arc suppression coil, grounding transformer, overvoltage protection cabinet（Device）, the devices such as arrester carry out Zenith tracking
It compares, the nonlinear dampling material in the application, when there is overvoltage problem, single-phase intermittence arc grounding over-voltage can be prevented
Generation, damp and transient suppression restore voltage climbing and amplitude, prevent cut-off overvoltage；Its energy effective damping is simultaneously
Resonance overvoltage between phase and phase is inhibited to reach protection purpose using material property with switching overvoltage.
In the utility model, the isolating device 7 is isolating transformer, and the isolating transformer acquires for protective current
Unit 6.
Isolating transformer in the utility model, primary coil are wound on an iron core, and secondary coil is wound on another iron
On core, realize most intuitive isolation by distance and theoretic electrical isolation, finally further through poured with epoxy resin, fundamentally protect
The converse of secondary power supply is demonstrate,proved, ensures the operational safety of power grid 18.
Further, it is also being equipped with twin-core shielding line 16 and aviation successively between current acquisition unit 6 and isolating device 7
Socket 17.Wherein, twin-core shielding line 16 has been exactly shielding action, does not make the distorted signals of acquisition.The effect of aviation socket 17 is just
It is to play excessive, connection, conversion, because general control unit is cabinet, and cabinet is fixed, and handcart is living
Dynamic, it needs to realize by aviation socket.
The having a rest property arc light it is found that when attached drawing 5 is the device without increasing non-damping and amortization material preparation is compared with reference to attached drawing 5-6
Earth current recording figure, when individual event intermittent arc grounding occurs for power grid 18 at this time, it is impossible to inhibit the generation of overvoltage in time.
With reference to attached drawing 6, having a rest property arc grounding current recording figure during device to increase non-damping and amortization material preparation, at this time
It can effectively inhibit the generation of normal phase harmfulness overvoltage, really when single-phase intermittent arc earthing occurs for power grid 18
Accomplish to ban arc suppression coil, prevent the breakdown of weak isolating electrical equipment, power system security is maintained reliably to run.
Non- damper assembly in the utility model has following characteristic:
1) every millimeter of variation is 20 volts,
2）In communication function, can on send action message.Stipulations are often used using electric power.
3）Crash analysis, can accurately reflect be that type overvoltage（It is switching overvoltage, resonance overvoltage, single-phase
Intermittent arc grounding overvoltage, lightning surge）, overvoltage actuation time is generally 2ms, reacts overvoltage actuation time,
Operation voltage value.
4）React overvoltage actuation time, operation voltage value.
The utility model can reflect that is mutually grounded and earth current size, and sends out alarm.When earth current is more than
Alarm signal can be sent out during 15mA.Digital ＆ analog signal access and on give, show busbar voltage and the information such as inlet wire current and alarm.It is comprehensive
It closes protective device main interface and shows primary system figure.
Previous Microcomputer Protection is using photoisolator, and the application, using isolating transformer, this is other
Microcomputer Protection does not all adopt used new technology.The overvoltage of different types can be accurately reflected：Switching overvoltage, resonance are excessively electric
Pressure, single-phase intermittent arc earthing overvoltage, lightning surge make high-low voltage obtain effective isolation, remove a hidden danger.
In the utility model, shunt resistance 19 is additionally provided between three phase network and earthed circuit, primarily to protecting
Protect power grid.
The operation principle of the utility model is：It is used for acquiring 4 tunnels in cabinet in high tension loop in General Electric Network 182
（General power grid 18 is three phase network 18, there is three tunnels；The terminal of three-phase converges becomes artificial neutral point together, in addition front three
Road forms thinking at this time）In measuring unit by electric current, by current acquisition unit and a whole set of electronic component, to signal
Do rectification, filtering, etc. processing amplification, by the main display of monitoring device can record, show each road waveform, judge three
Phase power line singlephase earth fault, record nearest 50 failures and pass through network interface, RS485 interfaces send background management system to.
The characteristics of the utility model：Data acquisition is not a single data acquisition module, it is a complete acquisition
System is made of a lot of electronic components, its picking rate is fast, and accurate, 4 channel highests 500K sampled point per second.
In the utility model, the principle of current collector is：Apply a different voltage in the line, signal is through sensing
Device and a whole set of electronic component, will obtain different current values in milliammeter, then by signal is done rectification, filtering, etc.
Processing amplification, records in the main display of integrated protection observing and controlling cabinet measure and control device, shows each road waveform, so as to judge three-phase electricity
The failures such as line of force road single-phase earthing, nearest 50 failures and pass through network interface, RS485 interfaces send background management system to.
In the utility model, by being detected in real time through the electric current in measuring apparatus, directly judged whether according to its numerical value
For overvoltage, method is simple, and the device needed is simple, more convenient to use.
The basic principle of the utility model and main feature and the advantages of the utility model has been shown and described above.One's own profession
The technical staff of industry is it should be appreciated that the present utility model is not limited to the above embodiments, described in above embodiments and description
Only illustrate the principle of the utility model, on the premise of not departing from the spirit and scope of the utility model, the utility model is also
Various changes and modifications are had, these various changes and improvements fall within the scope of the claimed invention.The utility model
Claimed range is defined by the appending claims and its equivalent thereof.
Claims (6)
1. a kind of judgment means of overvoltage in power grid, which is characterized in that including control unit, measuring apparatus, three phase network with
And the earthed circuit of three phase network ground connection, the measuring apparatus include being respectively arranged on the in the three phase network and earthed circuit
One measuring apparatus, the second measuring apparatus, third measuring apparatus and the 4th measuring apparatus；First measuring apparatus, second measure
The current acquisition list of detection measuring apparatus electric current is separately provided in equipment, third measuring apparatus and the 4th measuring apparatus
Member；The current acquisition unit is connect respectively with described control unit；Described control unit is used to compare current acquisition unit
Current value, and judged.
2. the judgment means of overvoltage in a kind of power grid according to claim 1, which is characterized in that the measuring apparatus is led to
Non- damping material is crossed to be prepared.
3. the judgment means of overvoltage in a kind of power grid according to claim 1, which is characterized in that described control unit with
The current acquisition unit is connected by isolating device.
4. the judgment means of overvoltage in a kind of power grid according to claim 3, which is characterized in that the isolating device packet
Include the resistance being sequentially connected in series between current acquisition unit and described control unit, diode rectifier bridge and capacitance, the resistance,
Diode rectifier bridge and capacitance are connect respectively with described control unit.
5. the judgment means of overvoltage in a kind of power grid according to claim 1, which is characterized in that described control unit is set
Be placed in housing, be respectively equipped with display device, interface, alarm and indicator light on the housing, described control unit respectively with
The display device, interface, alarm are connected with indicator light.
6. the judgment means of overvoltage in a kind of power grid according to claim 1, which is characterized in that described control unit is also
Module when being connected with GPS pairs.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721628672.2U CN207588441U (en) | 2017-11-29 | 2017-11-29 | The judgment means of overvoltage in a kind of power grid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721628672.2U CN207588441U (en) | 2017-11-29 | 2017-11-29 | The judgment means of overvoltage in a kind of power grid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207588441U true CN207588441U (en) | 2018-07-06 |
Family
ID=62734181
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721628672.2U Active CN207588441U (en) | 2017-11-29 | 2017-11-29 | The judgment means of overvoltage in a kind of power grid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207588441U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107769175A (en) * | 2017-11-29 | 2018-03-06 | 西安华桑科技发展有限公司 | The determination methods and device of overvoltage in a kind of power network |
-
2017
- 2017-11-29 CN CN201721628672.2U patent/CN207588441U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107769175A (en) * | 2017-11-29 | 2018-03-06 | 西安华桑科技发展有限公司 | The determination methods and device of overvoltage in a kind of power network |
| CN107769175B (en) * | 2017-11-29 | 2024-03-29 | 西安华桑科技发展有限公司 | Method and device for judging overvoltage in power grid |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103454517B (en) | Capacitance type potential transformer on-line monitoring method | |
| CN101571563B (en) | Integrative electric energy quality monitoring terminal | |
| CN105548814B (en) | A kind of distribution line ground fault judgment method and system | |
| JP6547217B2 (en) | Capacitor-type instrument transformer for transient overvoltage monitoring system | |
| CN205920158U (en) | DC power supply AC ripple monitoring devices | |
| CN104865489A (en) | System and method for overhead line fault location and monitoring | |
| CN102879667A (en) | Lightning protection device on-line remote monitoring recorder | |
| CN204142870U (en) | A kind of lightning arrester total current and action frequency wireless monitoring device | |
| CN206114790U (en) | Zinc oxide arrester on -line monitoring device | |
| CN204758748U (en) | Cubical switchboard intelligent integrated monitoring devices | |
| CN203026928U (en) | Separated type intelligent lightening protection system for wireless communication base station | |
| CN213986651U (en) | Multi-state online monitoring system for lightning arrester | |
| CN107247204A (en) | The condition monitoring system and monitoring method of voltage limiter in super, extra-high voltage series compensation device | |
| CN103698590A (en) | Real-time voltage monitor device of 10KV power distribution network | |
| CN104330615A (en) | Multi-phase measuring device of lightning arrester and transformer based on FFT algorithm and method thereof | |
| CN207588441U (en) | The judgment means of overvoltage in a kind of power grid | |
| CN202676797U (en) | Arc extinction resonance extinction and overvoltage protection device on-line monitoring system | |
| CN108089082A (en) | High voltage direct current neutral bus arrester performance on-line monitoring system and method | |
| CN107769175B (en) | Method and device for judging overvoltage in power grid | |
| CN202814597U (en) | High-voltage power transmission line temperature measuring system | |
| CN201237622Y (en) | On-line monitoring device for three-phase arrester in cabinet | |
| CN208672733U (en) | A kind of monitoring system based on SPD | |
| CN208654255U (en) | A kind of multi-functional Reactor Fault on-Line Monitor Device | |
| CN207798969U (en) | High voltage direct current neutral bus arrester performance on-line monitoring system | |
| CN203350385U (en) | Direct current system parasitic circuit on-line detection apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |