CN107064648B - The detection device and method of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable - Google Patents
The detection device and method of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable Download PDFInfo
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- CN107064648B CN107064648B CN201710181491.8A CN201710181491A CN107064648B CN 107064648 B CN107064648 B CN 107064648B CN 201710181491 A CN201710181491 A CN 201710181491A CN 107064648 B CN107064648 B CN 107064648B
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- resistance
- frequency signal
- lead
- lightning
- blower fan
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/16—Measuring impedance of element or network through which a current is passing from another source, e.g. cable, power line
- G01R27/18—Measuring resistance to earth, i.e. line to ground
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/20—Measuring earth resistance; Measuring contact resistance, e.g. of earth connections, e.g. plates
- G01R27/205—Measuring contact resistance of connections, e.g. of earth connections
-
- 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
- Y02E10/72—Wind turbines with rotation axis in wind direction
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The invention discloses the lightning-arrest lead resistance value detection device of blower fan pylon and method based on leakage cable, the detection device includes: resistance measurement high-frequency signal generation module, leaky cable, signal reception transmission processing module；Resistance measurement high-frequency signal generation module is mounted on blower column overhead, and the internal signal wire of resistance measurement high-frequency signal generation module is connected by the starting point of conducting wire and ground lead；Leaky cable and signal processing sending module are arranged in blower tower tower bottom, wherein leakage cable is arranged in ground lead naked section and passes through in the field domain generated when high-frequency signal, signal, which receives, to be sent processing module electrical connection leaky cable and is also connected with ethernet communication network, the measuring system of blower fan pylon connects the ethernet communication network, and the data handled through the measuring system are sent to the host computer for observing and measuring room.
Description
Technical field
The present invention relates to the technical fields of wind-power electricity generation, more particularly to the lightning-arrest lead of blower fan pylon based on leakage cable
The detection device and method of resistance value.
Background technique
Existing wind power generating set is all mounted in the wide plains region in field, and wind power plant is up to tens meters very
To rice up to a hundred, causes it to be easily struck by lightning and be directly becoming thunder and lightning connects sudden strain of a muscle object.Since blower interior structure is very compact, no matter
Blade, cabin or empennage are struck by lightning, and the equipment such as electric-control system in cabin may all be struck back by the high potential of cabin.In
Power supply and control loop along pylon draw under way in, it is also possible to struck back by high potential.In fact, for high among wilderness
Object is alarmmed, no matter how to protect, is impossible to avoid being struck by lightning completely.Therefore, it for the lightning protection of wind power generating set, answers
This lays stress on by how lightning current to be introduced the earth rapidly when being struck by lightning, and is reduced as far as importing the electricity of equipment by thunder and lightning
Stream ensures the safety of equipment and personnel to the maximum extent, and loss is made to be reduced to the smallest degree.The measurement deposited now is lightning-arrest to draw
The method of line resistance value is mainly as follows:
The principle of three electrode method measurement of Grounding Resistance is to inject hand generator between electric current pole and tested grounding body to generate
Low-frequency ac electric current, it is tested between grounding body and voltage pole obtain voltage U, by the electric current and voltage value, according to ohm
Law can calculate the ground resistance of tested grounding body.Three-level method will make a call to two auxiliary electrodes when measuring every time, on the one hand increase
Add manpower, on the other hand some wind power plants may beat electrode without field condition, and manual operation link is relatively more, to result
It influences bigger.
It using split-core type meter method measurement pole tower ground resistance is improved greatly the one of conventional method, when outstanding advantages are measurements not
Electric current pole and voltage pole lead must be laid, as long as clamping overhead line structures down conductor with split-core type meter, so that it may ground resistance is surveyed, but
The signal that this method uses is in low-frequency range, is easy to generate interference with certain signals of blower fan pylon itself, causes precision low
Or result is invalid.
It can be with therefore, it is desirable to there is a kind of blower fan pylon based on leakage cable to take shelter from the thunder the detection device of lead resistance value and method
Solve the drawbacks described above of the prior art.
Summary of the invention
The purpose of the present invention is to provide a kind of detection devices of lightning-arrest lead resistance value of the blower fan pylon based on leakage cable
And method carries out precise measurement to blower fan pylon grounding resistance and realizes that remote online measures.
To achieve the above object, the present invention provides the lightning-arrest lead resistance value detection device of blower fan pylon based on leakage cable,
The detection device includes: that resistance measurement high-frequency signal generation module, leakage cable and signal receive transmission processing module；
Resistance measurement high-frequency signal generation module is mounted on blower column overhead, resistance measurement high-frequency signal generation module
Internal signal wire connected by the starting point of conducting wire and ground lead；
It reveals cable and signal receives and sends processing module setting in blower tower tower bottom, wherein leakage cable setting is being grounded
Lead naked section passes through in the field domain generated when high-frequency signal, and signal, which receives, to be sent processing module electrical connection leakage cable and go back
Ethernet communication network is connected, the measuring system of blower fan pylon connects the ethernet communication network, and will be through the measurement
The data of system processing are sent to the host computer for observing and measuring room.
Preferably, the power supply mode of the resistance measurement high-frequency signal generation module is self-powered power supply, the resistance
High-frequency signal generation module is measured according at the top of the blower fan pylon, and the resistance measurement high-frequency signal generation module is close
Encapsulation is closed, to reduce external interference.
The present invention also provides the detection methods of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable, including following step
It is rapid:
(1) measure resistance: measuring ground lead resistance using Ohm's law, in measurement, by high-precision constant pressure source and
Reference resistance links together with lightning-arrest lead, sample by the voltage value to reference resistance both ends and combines Ohm's law
It is analyzed, obtains the resistance performance state of ground lead；
(2) resistance is sent: the resistance value that resistance measurement high-frequency signal generation module is measured according to step (1), is generated different
The signal of frequency, while in order to avoid the low frequency signal of blower fan pylon itself generates interference to measurement, signal frequency is arranged in height
Frequently, i.e. MHz, the signal of generation enter ground lead after enhanced processing, and the frequency by reading the signal, which changes, to be connect
The resistance value of ground resistance；
(3) resistance receives: after the high-frequency signal that resistance measurement high-frequency signal generation module generates enters ground lead, connecing
The naked section of ground lead will form stable electromagnetic field, and leakage cable is placed in the field domain, realizes the reception of high-frequency signal,
The signal received is transferred in signal reception transmission processing module and is pre-processed；
(4) resistance is read: host computer reads the pretreated data of signal receiving processing module through each assembling, and right
Preprocessed data is further processed, the resistance value specifically measured.
Preferably, the reference resistance of the step (1) chooses high-accuracy standard for manual sampling resistance to guarantee enough measurement essences
Degree, resistance precision 0.01%.
Preferably, the resistance accuracy of the ground resistance of the step (2) is set as 0.1 Ω.
The detection device and method of the lightning-arrest lead resistance value of blower fan pylon proposed by the present invention based on leakage cable are utilized and are let out
Dew cable realizes that blower fan pylon grounding resistance precise measurement realizes simultaneously using simple device with cheap cost and remotely exists
Line measurement, can completely remove manpower, reduce the consumption of man power and material to greatest extent.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the detection device of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable.
Fig. 2 is the circuit connection diagram of resistance measuring module and high-frequency signal generation module.
Fig. 3 is the flow chart of the detection method of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable.
Fig. 4 is the communication network schematic diagram of the detection device of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable.
Specific embodiment
To keep the purposes, technical schemes and advantages of the invention implemented clearer, below in conjunction in the embodiment of the present invention
Attached drawing, technical solution in the embodiment of the present invention is further described in more detail.In the accompanying drawings, identical from beginning to end or class
As label indicate same or similar element or element with the same or similar functions.Described embodiment is the present invention
A part of the embodiment, instead of all the embodiments.The embodiments described below with reference to the accompanying drawings are exemplary, it is intended to use
It is of the invention in explaining, and be not considered as limiting the invention.Based on the embodiments of the present invention, ordinary skill people
Member's every other embodiment obtained without creative efforts, shall fall within the protection scope of the present invention.Under
Face is described in detail the embodiment of the present invention in conjunction with attached drawing.
As shown in Figure 1, fan blade and wheel hub, which are mounted on the equipment above blower fan pylon, connecting wire, these conducting wires
It is merged at the total meeting point 5 of starting point, ground lead ground resistance refers to the resistance from starting point to earthing or grounding means, resistance measurement
High-frequency signal generation module 1 is mounted on tower top, and internal signal wire is connected to by the starting point of common conducting wire and ground lead
Together, the power supply mode of resistance measurement high-frequency signal generation module 1 chooses self-powered power supply, can according to need and is mounted on wind
Any appropriate position of machine tower top, and the module uses closed processes, reduces external interference to the greatest extent；
Signal, which receives, to be sent processing module 2 and reveals the bottom end that cable 3 is mounted on blower fan pylon, wherein leakage cable 3 is set
Set in the field domain generated when ground lead naked section 4 passes through high-frequency signal, signal receive send processing module 2 on the one hand will be with
It reveals cable 3 to connect, on the other hand to access in entire ethernet communication network；Entire Ethernet connects each blower fan pylon
Measuring system, and they are pooled to and is observed and measured in indoor host computer.
As shown in Figures 2 and 3, Rx indicates that the ground resistance of lightning conductor, R indicate the reference electricity of the access system in test
Resistance, FR indicate isolation relay, the connection when system starts test, while can protect test module under non-test state
From the damage of lightning stroke.K1, k2 indicate controllable switch, with the carry out on-off of testing process when test.Exposed ground section indicates
At blower fan pylon Bottom ground conducting wire exposed a bit of (also referred to as grounding rod).
It is as follows to measuring principle and process description in conjunction with the flow chart of figure three:
System start-up phase: after connecting FR, system starts；
The measuring phases of ground lead resistance value: the present invention measures resistance using Ohm's law, k1 closure, and k2 is disconnected
It opens, constant pressure source and sample circuit and system are connected, and constant pressure source internal resistance can be ignored systematic influence, and constant source voltage value is
U, sampled point measure reference resistance (resistance value R) both end voltage be U1, then the resistance value for needing to measure can calculate it is as follows:
To guarantee measurement accuracy, the error of single measurement is avoided, repeatedly measurement is needed to take mean value；
Signal generate the stage: after the completion of resistance measurement, disconnect k1, connect k2, signal generator according to measurement resistance not
The signal of different frequency is generated with situation.The signal enters in ground lead after amplifying unit；In order to effective earth's surface
Show the size of ground lead resistance value, this patent is compiled using the high-frequency signal for choosing two different frequencies using serial binary
Code format re-sends to ground lead after being arranged, and pre-sets the corresponding ground lead resistance of various coded formats
It is worth size, and number of encoding bits are more, it will be able to which the more accurate resistance for indicating ground lead, binding test use-case are had
Body is described as follows:
In testing choose two kinds of frequency signals of 30MHz and 35MHz, need to indicate in the measurements section [1 Ω, 11 Ω)
Resistance value, and it is 0.1 Ω that the progressive value of resistance value (resistance value span), which is arranged, needs 100 kinds of binary coded values altogether, so setting is serial
Binary coding digit is 7, total to generate 27=128 kinds as a result, choose 100 kinds of possible situations and by various situations with
The resistance value situation that can be measured that corresponds, such as in testing shown in the following table of expression situation of 4.0 Ω:
In this 100 kinds of coding situations, it may appear that adjacent two or the identical situation of a few bit frequencies, when resistance value judges
It can be identified according to every duration.
Thereby realize the downward transmitting of specific resistance value.
Signal receive and transmission phase: the stage is illustrated in two kinds of situation: the first situation be ground lead
Any signal will not be sensed through because failure disconnects, revealing cable in this case；Another situation is that leakage cable energy
It enough senses high-frequency signal, illustrates ground lead at least without disconnection, signal, which receives, sends processing module 2 to the signal received
It is pre-processed, host computer is then sent it to by Ethernet；
Signal differentiates the stage: host computer receives the signal that each Fans are sent, preceding in advance according to measurement is started
The serial frequency coded meanings of the different frequency composition of setting carry out identification to the resistance value of ground lead and show, complete primary survey
Amount.
As shown in figure 4, whole system applies the structural schematic diagram in wind power plant, signal, which receives, sends processing module 2 in advance
Signal after processing is sent to host computer by ethernet communication module after A/D conversion.
The detection device and method of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable of the invention have with following
Beneficial effect:
1. can quickly detect that blower fan pylon is taken shelter from the thunder wire ground resistance size in real time.
2. hardware has carried out calculation process to signal, the utilization rate of equipment is improved.
3. software can be installed on the indoor computer of master control to be shown, conveniently to check, reduction is unnecessary to hurry back and forth,
Not spending can be observed under blower fan pylon.
4. hardware configuration is simple, it is easily installed, blower groundwork will not be impacted, while controllability is good.
5. having good ductility, multiple blower fan pylons can be monitored simultaneously.
6. good modularization feature allows the invention to be well embedded in other blower fan pylon equipment, have fine
Compatibility, bring great convenience for the work of Field Force.
Finally it is noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations.To the greatest extent
Present invention has been described in detail with reference to the aforementioned embodiments for pipe, those skilled in the art should understand that: it is still
It is possible to modify the technical solutions described in the foregoing embodiments, or part of technical characteristic is equally replaced
It changes；And these are modified or replaceed, the essence for technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution
Mind and range.
Claims (5)
- The lead resistance value detection device 1. the blower fan pylon based on leakage cable is taken shelter from the thunder, which is characterized in that the detection device includes: Resistance measurement high-frequency signal generation module, leakage cable and signal, which receive, sends processing module；Resistance measurement high-frequency signal generation module is mounted on blower column overhead, resistance measurement high-frequency signal generation module it is interior Portion's signal wire is connect by conducting wire with the starting point of lightning-arrest lead；It reveals cable and signal receives and sends processing module setting in blower tower tower bottom, wherein leakage cable is arranged in lightning-arrest lead Naked section passes through in the field domain generated when high-frequency signal, and signal, which receives, to be sent processing module electrical connection leakage cable and be also connected with Ethernet communication network, the measuring system of blower fan pylon connect the ethernet communication network, and will be through the measuring system at The data of reason are sent to the host computer for observing and measuring room.
- The lead resistance value detection device 2. the blower fan pylon as described in claim 1 based on leakage cable is taken shelter from the thunder, it is characterised in that: The power supply mode of the resistance measurement high-frequency signal generation module is self-powered power supply, and the resistance measurement high-frequency signal generates Module is mounted at the top of the blower fan pylon, and the resistance measurement high-frequency signal generation module enclosed package, outer to reduce Boundary's interference.
- The detection method of lead resistance value 3. the blower fan pylon based on leakage cable is taken shelter from the thunder, which comprises the following steps:(1) it measures resistance: the resistance of lightning-arrest lead is measured using Ohm's law, in measurement, by high-precision constant pressure source and ginseng Resistance is examined to link together with lightning-arrest lead, by the voltage value to reference resistance both ends carry out sample and combine Ohm's law into Row analysis obtains the resistance of lightning-arrest lead；(2) resistance is sent: the resistance value that resistance measurement high-frequency signal generation module is measured according to step (1) generates different frequency Signal, while in order to avoid the low frequency signal of blower fan pylon itself generates interference to measurement, in high frequency, i.e., signal frequency is arranged MHz, the signal of generation enter lightning-arrest lead after enhanced processing, and the electricity of lightning-arrest lead is obtained by the frequency variation of the signal Resistance；(3) resistance receives: lightning-arrest to draw after the high-frequency signal that resistance measurement high-frequency signal generation module generates enters lightning-arrest lead The naked section of line will form stable electromagnetic field, and leakage cable is placed in the field domain, realizes the reception of high-frequency signal, is received To signal be transferred to signal receive send processing module in pre-processed；(4) resistance is read: host computer reads the pretreated data of signal receiving processing module through each assembling, and to pre- place Reason data are further processed, the resistance specifically measured.
- The detection method of lead resistance value 4. the blower fan pylon as claimed in claim 3 based on leakage cable is taken shelter from the thunder, feature exist In: the reference resistance of the step (1) chooses high-accuracy standard for manual sampling resistance to guarantee enough measurement accuracy, resistance precision 0.01%.
- The detection method of lead resistance value 5. the blower fan pylon as claimed in claim 3 based on leakage cable is taken shelter from the thunder, feature exist In: the resistance precision of the ground lead of the step (2) is set as 0.1 Ω.
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| CN201710181491.8A CN107064648B (en) | 2017-03-24 | 2017-03-24 | The detection device and method of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable |
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| CN201710181491.8A CN107064648B (en) | 2017-03-24 | 2017-03-24 | The detection device and method of the lightning-arrest lead resistance value of blower fan pylon based on leakage cable |
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| CN107064648A CN107064648A (en) | 2017-08-18 |
| CN107064648B true CN107064648B (en) | 2019-11-29 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| EP3626965A1 (en) * | 2018-09-21 | 2020-03-25 | Siemens Gamesa Renewable Energy A/S | Object position and/or speed and/or size and/or direction detection device for a wind turbine |
| EP3719475A1 (en) * | 2019-04-01 | 2020-10-07 | Siemens Gamesa Renewable Energy A/S | Method and apparatus for performing measurements and monitoring of an object |
| EP3719309A1 (en) * | 2019-04-01 | 2020-10-07 | Siemens Gamesa Renewable Energy A/S | Apparatus for and method of detecting one or more properties of a rotor blade during operation of a wind turbine |
| EP3719307A1 (en) * | 2019-04-01 | 2020-10-07 | Siemens Gamesa Renewable Energy A/S | Distributed system for and method of detecting position and/or speed of a rotor blade during operation of a wind turbine |
| EP3719303A1 (en) * | 2019-04-01 | 2020-10-07 | Siemens Gamesa Renewable Energy A/S | Electromagnetic measurements for a wind turbine |
| EP3719528A1 (en) * | 2019-04-01 | 2020-10-07 | Siemens Gamesa Renewable Energy A/S | Detecting properties of a moving object at a wind turbine site using a beam forming arrangement of leaky feeders |
| CN112904085B (en) * | 2021-01-15 | 2022-07-08 | 江苏双瑞风电叶片有限公司 | Device and method for automatically measuring resistance value of lightning protection system of wind power blade |
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| JPH0632257B2 (en) * | 1988-04-21 | 1994-04-27 | 株式会社東芝 | Deterioration detection device for lightning arrester |
| CN100397087C (en) * | 2006-02-21 | 2008-06-25 | 武汉高压研究所 | Pole tower earthing resistance quick testing method without unfastening wire and device |
| CN103954843B (en) * | 2014-05-21 | 2016-06-15 | 重庆大学 | One does not disconnect ground lead pole tower ground resistance and measures injection power frequency method of determining range |
| CN205751108U (en) * | 2016-06-24 | 2016-11-30 | 乌鲁木齐经济技术开发区有线电视网络传输有限公司 | A kind of safety defense monitoring system |
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