JP2019039411A - Windmill having soundness detection system of down conductor - Google Patents

Abstract

To provide a windmill having a soundness detection system of a down conductor, capable of measuring a maximum temperature at a position of each down conductor for each lightning.SOLUTION: A windmill having a soundness detection system of a down conductor comprises a hub, a plurality of blades supported by the hub, a rotor shaft pivoting the hub, a nacelle storing the rotor shaft, and a tower supporting the nacelle, where each blade includes a sensor array comprising: a receptor; a down conductor provided across the receptor and the hub; and a plurality of temperature sensors parallely and continuously arranged over the substantially entire length of the down conductor.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a windmill having a soundness detection system, and more particularly to measures against lightning strikes on windmill blades (blades) having a soundness detection system for wind power generation facilities.

  In recent years, wind power generation facilities tend to increase the size of wind turbines having soundness detection systems in order to obtain large electric power. The height of the wind power generation equipment is 100 m or more at a high height even when constructed on the ground, and the diameter of the wind turbine blade (blade) having the soundness detection system is also 80 m or more. In the case of construction on the ocean, wind turbines with a height of 180 m or more have been developed.

  As the wind power generation facilities increase in size and the ground height (sea level) of a wind turbine having a soundness detection system increases, the damage ratio of lightning strikes on the blades increases.

  When a blade is subjected to lightning strikes, there is a direct impact on power generation, so it is necessary to take measures against lightning strikes on the blade. As measures against lightning strikes, a plurality of receptors are installed according to the size of the blade, and receptors are arranged at the tip and edge portions of the blade. And the down conductor (down conductor) of the equipment structure which can discharge the lightning current lightning received by this receptor to the earth safely is provided.

  In particular, when the down conductor does not function sufficiently, blades often cause serious accidents such as burnout and breakage, and it is important to grasp the soundness of the down conductor. However, there is no device that can directly grasp the soundness of the down conductor. About once a year, the surface of the blade is visually inspected by an aerial work vehicle, etc., and the blade is cut according to the situation to grasp the state of the down conductor. ing. For this reason, a device capable of grasping the soundness of the down conductor for each lightning strike is required.

  As an example of measures against lightning strikes on a blade, for example, in Patent Document 1, temperature sensors are provided at a plurality of locations of a blade composed of a conductive CFRP composite material, and a predetermined period of the blade (CFRP) is determined by each temperature sensor. When the temperature information is equal to or greater than the threshold value, the measured temperature information is compared with a threshold value (a value determined based on the temperature affected by the heat of the composite resin material). A device that determines that (blade) is damaged by a lightning strike.

  Further, as Patent Document 2, a conductive receptor provided at the tip of a blade and two down conductors connected to the receptor and guiding a lightning current temporarily generated by a lightning strike to a grounding part are provided. A soundness evaluation system is disclosed in which a pulse voltage is applied to the downconductor of each of the two conductors, and the normality, disconnection, and fusion of the downconductors are detected by an optical fiber current sensor provided on the two downconductors so as to improve the soundness of the downconductors. (Paragraph ~).

JP 2013-139734 A JP 2017-96193 A

  However, Patent Document 1 is a countermeasure against lightning strike of a blade made of a conductive CFRP composite material, and does not consider the soundness of the down conductor.

  Moreover, in patent document 2, the soundness evaluation which confirms the soundness of a down conductor to the fine position of a down conductor was not considered.

  An object of the present invention is to provide a wind turbine having a health detection system that can measure the maximum temperature at each position of the down conductor for each lightning strike and has a health detection system for the down conductor.

  Another object of the present invention is to provide a wind turbine having a down conductor soundness detection system that improves the maintainability of the down conductor.

  In order to solve the above-described problems, the present invention provides a wind turbine having the following down conductor soundness detection system. That is, as the first invention, each of the blades includes a hub, a plurality of blades supported by the hub, a rotor shaft that supports the hub, a nacelle that stores the rotor shaft, and a tower that supports the nacelle. Has a down conductor health detection system including a receptor, a down conductor provided from the receptor to the hub, and a sensor array including a plurality of temperature sensors arranged in parallel and continuously over substantially the entire length of the down conductor. Windmill (corresponding to claim 1).

  2. The down conductor health detection system according to claim 1, wherein each sensor of the sensor array of the down conductor health detection system uses a resistance wire for measurement for acquiring temperature information as a temperature sensor in addition to the feature. A windmill having the following structure (corresponding to claim 2).

  The wind turbine having the down-conductor health detection system according to claim 1 or 2, wherein the sensor array is housed in an insulating sheath in a blade.

  The wind turbine having the down conductor soundness detection system according to claim 3, wherein the insulating sheath is housed in a flexible metal hose in addition to the characteristics (corresponding to claim 4).

  In addition to the above features, the down-conductor soundness detection system acquires the resistance value information of the resistance wire for measurement in association with the position in the blade, and the position-based resistance value acquisition unit. The temperature change information recording part which records the temperature information based on the resistance value information performed as temperature change information which is the information linked | related with the said position and measurement time, It further has any 1 item | term of Claim 4 A wind turbine having a down conductor soundness detection system (corresponding to claim 5).

  In addition to the above feature, the down-conductor health detection system is a lightning strike position information which is information relating a lightning strike to a blade or an image or / and video of a wound caused by a lightning strike to a blade and time information. A windmill having the down-conductor soundness detection system according to any one of claims 2 to 5, further comprising a lightning position information acquisition unit for acquiring the lightning position information acquisition unit (corresponding to claim 6).

  In addition to the above features, the down-conductor health detection system further includes a time information input unit, and an observation information output unit that outputs observation information including temperature change information and lightning position information based on the input time information. A wind turbine having the down conductor soundness detection system according to claim 6 (corresponding to claim 7).

  A down conductor soundness detection system according to claim 1 (corresponding to claim 8).

  According to the configuration described above, it is possible to provide a wind turbine having a down conductor soundness detection system that can measure the maximum temperature at each position of the down conductor for each lightning strike. In addition, it is possible to provide a wind turbine having a down conductor soundness detection system that improves the maintainability of the down conductor.

Conceptual diagram of a windmill (wind power generation facility) having the soundness detection system of the present embodiment Functional block diagram of a wind turbine having the soundness detection system of Embodiment 1 Functional block diagram of a wind turbine having the soundness detection system of Embodiment 1 Arrangement diagram of temperature sensor array (resistance wire for measurement) in blade of windmill having soundness detection system of embodiment 1 The figure for demonstrating fusing of a down conductor when a lightning strike (lightning strike) is received by the down conductor of the braid | blade of Embodiment 1. The figure which shows the temperature change in the position in a braid | blade when the lightning strike of Embodiment 1 is received. Configuration diagram of down conductor soundness detection system according to Embodiment 1 The figure for demonstrating arrangement | positioning of a soundness detection system to Embodiment 1. FIG. (A) (b) The figure which shows the example which used the Wheatstone bridge for the lightning strike measurement of a soundness detection system The figure for demonstrating the temperature measurement of the temperature sensor array in Embodiment 1. Conceptual diagram of lightning strike measurement by Wheatstone bridge of health detection system of embodiment 1 The figure which shows the other example (series connection) which used the Wheatstone bridge for the lightning strike measurement of the soundness detection system of Embodiment 1. The figure which shows the example of accommodation of the insulating sheath of the sensor array of Embodiment 1. The figure which shows the flexible metal hose accommodation example of the insulating sheath of Embodiment 1. Functional block diagram of a wind turbine having the soundness detection system of the second embodiment Functional block diagram of a wind turbine having the soundness detection system of the second embodiment Functional block diagram of optical space communication of acquired information acquired in the blade in the embodiment Functional block diagram of optical space communication of acquired information acquired in the blade in the embodiment The figure which shows the example of an interface of the resistance value acquisition part with a position of Embodiment 2. The figure which shows the example of an interface of the temperature change information recording part of Embodiment 2. Functional block diagram of a windmill having the soundness detection system of Embodiment 3 Functional block diagram of a windmill having the soundness detection system of Embodiment 3 The figure which shows the example of the furniture which accommodated the windmill which has the imaging | photography soundness detection system of the braid | blade by the infrared camera of Embodiment 3. The figure which shows the example of an interface of the lightning strike position information acquisition part of Embodiment 3. The figure which shows the other example of the interface of the lightning strike position information acquisition part of Embodiment 3. Functional block diagram of a wind turbine having the soundness detection system of Embodiment 4 Functional block diagram of a wind turbine having the soundness detection system of Embodiment 4 The figure which shows the example of an interface of the observation information output part of Embodiment 4.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to these embodiments, and can be implemented in various modes without departing from the spirit of the present invention.
<Embodiment 1>
<Overview of Embodiment 1>

The present invention is a system for detecting the soundness of a down conductor for grounding a lightning current such as a large windmill. Specifically, a large number of temperature detection sensors are provided according to each position along the down conductor of each blade. By arranging them, it is possible to grasp the damage state of the down conductor due to lightning over the entire length of the down conductor.
<Configuration of Embodiment 1>

As shown in FIG. 1, the windmill is configured. First, the whole structure of a windmill is demonstrated as a premise which demonstrates this invention. A windmill having a health detection system according to the first embodiment includes, for example, a windmill blade having a health detection system including three blades 0101 in a wind power generation facility 0100, a tip hub 0102 provided at the rotation center of the blade 0101, The rotor shaft 0103 is provided with a speed increaser 0104, a brake device 0105, and a generator 0106 through a power transmission shaft 0112. Here, the nacelle 0107 includes a rotor shaft 0103, a power transmission shaft 0112, a speed increaser 0104, a brake device 0105, and a generator 0106. When wind hits the blade portion of the blade 0103, the blade rotates, the rotation speed is increased by the gear of the gearbox 0104, the rotation speed is increased, and the generator 0106 generates power. The generated electricity is boosted by the transformer 0109 through the tower 0108, and electricity (electric power) is supplied from the grid connection protection device 0110 and the power system 0111 through the transmission line and the distribution line.
In the following description, the length of the blade is assumed to be about 40 m, but this is of course not limited.

  FIG. 2 is a functional block diagram of the present invention. As shown in FIG. 2, the wind turbine 0200 having the down-conductor health detection system of Embodiment 1 includes a hub 0203, a plurality of blades 0201, 0202, a rotor shaft 0205, a nacelle 0204, and a tower 0206. The blades 0201 and 0202 are provided with receptors 0207 and 0208, down conductors 0211 and 0221, and sensor arrays 0212 and 0222 each including a plurality of temperature sensors. The portion provided in the blade mainly constitutes the down conductor soundness detection system 0210. The temperature sensor may be a measurement resistance wire. The change in temperature is measured by the change in resistance value.

FIG. 3 shows this, but the difference is that the temperature sensor array provided in the blade is specifically a resistance wire for measurement, and the other points are the same as those in FIG. is there. In the following description of the configuration, description will be made with reference to FIG. 2 as appropriate, with reference to the measurement resistance wire 0312 in FIG. 3 as appropriate.
<Description of Configuration of Embodiment 1>
<Embodiment 1 Configuration Overall Hub>

The “hub” 0203 includes a signal aggregation device connected to a sensor array including a plurality of temperature sensors. This is because the number of sensors in the sensor array reaches several tens even with one blade, and it is complicated to wire each wiring from the hub into the nacelle. The signal aggregating apparatus may be a semiconductor electric circuit changeover switch or a switch circuit configured on a printed circuit board, and corresponds to, for example, a multiplexer, but is not limited thereto. Moreover, it is preferable that the hub has an analog-digital conversion circuit for digitizing a signal in addition to an electric circuit changeover switch. The analog signal is preferably converted into temperature information by an element provided in the hub. As an example, it is conceivable to use a Wheatstone bridge, but the present invention is not limited to this.
<Embodiment 1 Configuration Blade>

  “Blades” 0201 and 0202 are blades supported by the hub 0203 and play a role of converting wind force into rotational force. The blade is generally configured so that the angle of attack can be changed in accordance with the strength of the wind, and many ideas are made to effectively convert the force of the wind into a rotational force. The surface material of the blade is reinforced plastic or the like and is a non-conductive material. Further, the blade is structurally strong because it receives a large stress, and is reinforced with carbon fiber or glass fiber.

    The problem with blades is that they are vulnerable to lightning strikes, and usually down conductors are incorporated along the length of the blades to ground the lightning current. The material is a material having good conductivity, and a copper alloy is generally used. As for the structure of the copper alloy, in a region where lightning strikes frequently, the specification is such that the charge amount can withstand 300 clones. However, because of its good electrical conductivity, its melting point is low, and there is always a risk of structural weakening due to the temperature rise of lightning.

The down conductor is electrically connected to a part called a receptor for intentionally guiding lightning strikes, thereby reducing the probability of lightning strikes to the surface of the non-conductive material of the blade. In addition, this receptor is generally disposed at the tip portion of the blade, but there are also cases where it is disposed at a middle portion other than the tip of the blade with the intention of reducing lightning strike to the non-conductive surface as much as possible.
<Embodiment 1 Configuration Hub Down conductor soundness system part>
<Sensor array>

  As shown in FIG. 4, each blade includes a sensor array including the above-described receptor, a down conductor provided from the receptor to the hub, and a plurality of temperature sensors arranged in parallel and continuously over substantially the entire length of the down conductor. I have. The sensor array is provided so that each sensor array can be identified one by one on which position the sensor array is on the signal processing side. For example, signal processing is performed so that it can be understood how many meters from the tip position of the blade the sensor is provided.

  The down conductor and the sensor array are configured in an insulated state. This is because the sensor array is configured to avoid lightning current intrusion as much as possible.

Various sensors can be used in the sensor array, one of which is a resistance wire for measurement. In addition, various temperature sensors such as a thermocouple sensor, a semiconductor temperature sensor, and an infrared image utilizing type temperature sensor can be used. The sensor array can be formed separately from the down conductor along the down conductor. However, it is also conceivable to provide a pipe line in the down conductor and insulate it there. This is because if the lightning strike is not on the down conductor side but on the sensor array side, the sensor array itself may be damaged because the heat capacity is small.
<Embodiment 1 Configuration Rotor shaft>

A “rotor shaft” 0205 supports the hub 0203, and outputs rotational energy for generating electricity through power transmission to a generator or the like (not shown) disposed in the nacelle 0204 with the rotation of the blade. Blade temperature information signal-processed in the hub may be guided into the nacelle by a different path from the rotor shaft, but in some cases, a pipe line is provided in the rotor shaft and guided into the nacelle through the rotor shaft. You may comprise as follows. In general, the rotor shaft receives a large stress from the blade and transmits it to the generator to convert it into electric power, so it must be made structurally strong, such as stainless steel, reinforced stainless steel, etc. Used. When the blade length is about 40 meters, the rotor shaft diameter ranges from 50 centimeters to about 70 centimeters. It is also possible to configure the previous pipe line by hollowing out the inside of this diameter.
<Embodiment 1 Configuration Nacelle>

“Nacelle” 0204 stores the rotor shaft. When the wind turbine is a wind power generation facility, the nacelle 0204 stores a speed increaser, a brake device, a generator, and the like in addition to the rotor shaft. At the time of maintenance of the windmill 0200, the worker climbs from the tower 0206 to the nacelle and performs work such as repair and inspection in the nacelle. For example, the height of the nacelle is 70 m or more in the case of a ground windmill. In the nacelle, a signal processing result acquisition device for acquiring a result of processing a signal from the sensor array is installed. The data of the down conductor soundness detection system is not used by the windmill itself but information used by the management base via the network, and is preferably converted into a stronger signal structure in the nacelle. In other words, this down conductor soundness system is particularly useful in extremely poor communication environments such as lightning strikes, so it must be multiplexed and redundant so that no missing information is caused by large current noise. Is preferred. The processing is preferably performed as close to the signal source as possible from the viewpoint of noise risk. Therefore, it is preferable that the signal is converted into a strong structure in the hub or the nacelle. In the nacelle, it is preferable to provide an accumulator for accumulating temperature information acquired by the sensor array as a measure for fail-safe. This is to make it possible to use data stored in the storage unit even if information from the sensor array is lost during transmission. Data can be stored using a hard disk drive, a ROM device, a DVD recording device, or the like. The information from the sensor array is used not only for checking the soundness of the down conductor, but also for checking the safety of the windmill itself. For example, it is preferable to configure to detect the occurrence of a fire, the collapse of a blade, or the like using information processing. Such information is used for an emergency stop of the windmill.
<Embodiment 1 Other Information transmission structure between hub and nacelle>

  As shown in FIG. 16, information transmission between the hub and the nacelle is preferably performed by optical transmission. In this case, it is difficult to use optical couplers or optical couplers because they are in a rotational relationship with each other. Therefore, it is conceivable to perform transmission using a surface light source. On the hub side, a circular or donut-shaped light transmission surface is provided around the hub rotation center, and the light transmission surface is configured to always output the temperature sensor signals and information of all blades. However, the light receiving surface is provided so as to always receive an optical signal from a part of the circular or donut-shaped hub side surface light source.

  <Embodiment 1 Configuration Tower>

The “tower” 0206 supports the nacelle 0204. There are also 60-70m or more. In the down-conductor health detection system, the collected temperature information can be transmitted from the nacelle through the tower to the ground control room near the tower or a remote operation management center. The optical fiber is used because the optical fiber transmission is resistant to electromagnetic noise generated by lightning.
<Embodiment 2 Outline Sensor = Resistance wire for measurement>

The second embodiment is based on the first embodiment. Each sensor of the sensor array of the down conductor soundness detection system uses a resistance wire for measurement for acquiring temperature information as a temperature sensor. For example, a nichrome wire generally used for a heating wire or the like can be used. Other materials may be used. For example, a material having a melting temperature higher than at least the melting temperature of the down conductor is preferable. Moreover, the resistance wire for measurement is preferably configured in a spring shape. This is because a spring-like configuration can flexibly cope with thermal deformation, thereby reducing the risk of disconnection at a stretch.
<Embodiment 3 Outline Sensor array IN Insulating sheath>

  The down conductor soundness detection system of the third embodiment is based on the first and second embodiments.

As shown in FIG. 13, the sensor array is housed in insulating sheaths 1301 and 1302 in the blade. This is because the sensor array transmits temperature information by an electrical signal, so that electrical contact with the outside causes information deterioration. It is preferable that the insulating sheath is a substance with little thermal deformation, and glass fiber, paper phenol material, paper epoxy material, glass composite material, glass epoxy material, Teflon (registered trademark) material, Teflon (registered trademark) composite material (Teflon) (Registered trademark) and glass, Teflon (registered trademark) and epoxy, etc.) Alumina (ceramics) material (material obtained by impregnating alumina powder into paper) and the like can be used.
<Embodiment 4 Outline Insulating sheath IN Flexible metal hose>

  The down conductor soundness detection system of the fourth embodiment is based on the third embodiment.

  As shown in FIG. 14, the insulating sheath is preferably housed in a flexible metal hose 1401. The shape of the blade and the shape of the down conductor are not necessarily composed of only a straight line, but a gentle curve may be drawn. In this case, the blade is properly arranged along the down conductor and external noise is shielded by a metal material. It is to do. Therefore, it is preferable to be configured to be installed on a flexible metal hose. In place of this flexible metal hose, a hollow down conductor can be used as described above. Even in this case, an insulating sheath is essential.

  <Details of Embodiment 5 Soundness Detection System of Down Conductor>

  <Embodiment 5 Detailed configuration>

  As shown in FIG. 15, the down conductor soundness detection system of the fifth embodiment is based on the first to fourth embodiments. The detailed configuration of the down-conductor soundness detection system further includes a positioned resistance value acquisition unit 1531 and a temperature change information recording unit 1532. The position-added resistance value acquisition unit 1531 and the temperature change information recording unit 1532 are provided in a computer 1507 disposed inside the hub 1503.

  <Embodiment 5 Detailed configuration Positioned resistance value acquisition unit>

  As shown in FIG. 17, the “positioned resistance value acquisition unit” 1531 arranges the resistance value within the blades 1501 and 1502 of the resistance value when each sensor of the sensor array is the measurement resistance line 1512. Acquired in association with the position. For acquisition, it is necessary to configure so that the both-end signal acquisition line of each measurement resistance line is distinguished at the time of the signal line aggregation processing at which position of which blade. That is, the signal lines aggregated from the blades 1501 and 1502 are arranged so as to determine in advance which position the measurement resistance line belongs to. In actuality, when switching which measurement signal line is activated, the signal of the measurement signal line is processed in association with the position information of the sensor. For example, the resistance value of the number 1 measuring resistance wire, the resistance value of the number 2 measuring resistance wire, the resistance value of the number 3 measuring resistance wire, etc. The position is located on the connecting side of the blade and hub 10 cm from the receptor at the blade tip. The position of the number 2 measuring resistance line is further from the position of the number 1 measuring resistance line to the connecting side of the blade and hub. Information such as the position of the number 3 measuring resistance wire located at the position of 10 centimeters is further located at the position of 10 centimeters from the position of the number 2 measuring resistance wire to the connection side of the blade and the hub. The resistance value acquisition unit with a position is stored in advance, and the resistance measured by using the identification information (for example, number 1, number 2, number 3,...) Of the resistance wire for measurement. And values can be processed in association with measurement position where the resistance value is outputted. Basically, it is preferable that the physical constants of all the sensors in the sensor array are constant in order to simplify the calculation process for converting to a later temperature or the like. For example, when the sensor is a resistance wire for measurement, it is preferable that the resistance value is all constant. For example, the resistance value of the measuring resistance wire of one sensor is 1.08 plus or minus 0.05 micro ohm meter (volume resistivity), and the resistance temperature count is 140 between 20 degrees Celsius and 1000 degrees Celsius. (X10 minus 6 / ° C). Furthermore, the thermal expansion coefficient is 18 (× 10 minus 6 / ° C.), the melting point is 1400 ° C., and the density is 8.41 (gram · cubic centimeter). This is a case where a nickel chromium (nichrome) wire is used. When a nickel chromium wire is used, the coefficient of resistance increase with temperature is 1.00 at 20 ° C, 1.009 at 100 ° C, 1.009 at 200 ° C, 1.024 at 200 ° C, 1. 039, 1.056 at 400 ° C, 1.056 at 500 ° C, 1.070 at 600 ° C, 1.068 at 700 ° C, 1.062 at 800 ° C, 1.060 at 800 ° C, 1 at 900 ° C 0.063 at 1000 ° C, 1.070 at 1100 ° C, 1.080 at 1200 ° C, and preferably about 1.093 at 1200 ° C. The resistance wire for measurement may be a resistance wire having a circular cross section, or may be a strip-shaped resistance wire having a rectangular cross section.

The interface of the resistance value acquisition unit with position 1531 in FIG. 17 will be described. The acquisition information of the position-attached resistance value acquisition unit is composed of “position in blade” and “resistance value information of resistance wire for measurement”. The positioned resistance value acquired by the positioned resistance value acquisition unit may be an absolute value of the resistance value of the resistance wire for measurement or a difference from the resistance value at room temperature. “Acquisition of resistance value information” means to acquire a voltage value for a constant current and to acquire a current value for a constant voltage value. The current value and voltage value acquired in this form are included. Is substantially defined as obtaining a resistance value.
One technique for grasping the change in resistance value as a difference from the resistance value at normal temperature is to connect a measuring resistance wire, which is a sensor, to a Wheatstone bridge to detect the potential of the bridge portion. In this case, of the four resistors of the Wheatstone bridge, three are resistors having a resistance value equivalent to that of the measurement resistance wire in the normal temperature state, and the remaining one is the resistance of the blade sensor. In this case, the increment of the resistance value of the sensor is grasped as the detection potential of the bridge portion, and this increment becomes the resistance value information of the resistance wire for measurement. The resistance value information may include a difference from the resistance value at normal temperature.
In the figure, the resistance value from normal temperature indicates the change (ΔT), and the temperature information also indicates the change (ΔT). “1” in the blade position indicates, for example, the position farthest from the hub (blade tip) and is numbered in order. The resistance value “0” indicates that the temperature is normal temperature, which is 30 ° C. or more in the summer, and different depending on the location in the winter, for example, a negative value should be entered. However, the problem with the present invention is to know the soundness of the down conductor. The temperature information at the time of lightning strike is important, and there is no problem with the information at normal temperature. Therefore, the resistance value data at room temperature is set to “0”. The temperature information “0” indicates that the temperature information during lightning strike (lightning strike) is zero. That is, no lightning strikes have occurred and no lightning strikes have been received. The range of temperature information to be actively collected is 200 degrees to 600 degrees. When the wind turbine according to the fifth embodiment is applied to a wind power generation facility, for example, continuous operation is possible at 200 degrees, operation equipment needs to be checked at 300 degrees, and emergency use of information such as an emergency stop is performed at 600 degrees. Can be considered.

  The acquired information is recorded in a non-volatile recording medium such as a hard disk of the computer 1507, and the computer is batch-processed for a predetermined period (1 second, 1 minute, 1 hour, 1 day, 1 week, 1 month, every 6 months). An optical space transmission unit (not shown) to which 1507 is connected is transmitted to an optical space reception unit 1508 in the nacelle, and is transmitted to a control station (operation monitoring center) or the like via an optical communication cable. Also good. In the nacelle, a maintenance worker may connect an optical USB memory or the like to the optical space receiving unit 1508, download the data of the computer 1507, import the data into a maintenance personal computer, and use it for analysis. In addition to periodic batch processing, information may be transmitted in real time when it is determined that a lightning strike has occurred, that is, when the resistance value of the sensor has suddenly increased. The same applies to temperature change information recorded in a temperature change information recording section described later, as well as to the resistance value information with position.

  FIGS. 16A and 16B are schematic configuration diagrams of the optical space communication system. As shown in FIG. 16 (a), three optical signal irradiation surfaces of the optical space transmission unit arranged in three spaces on the rotor on the blade rotating body side are arranged, and each outputs all the information on the three blades. Is configured to do. As shown in FIG. 16B, each optical signal irradiation surface is configured so that information can be optically transmitted in real time in synchronization with the rotation of the blade, and the light receiving side has a light receiving surface that does not cover the entire circumference in the nacelle. is set up. Since the lightning strike information is important for the momentary light, it is desirable to adopt a configuration capable of such optical space communication. Conversely, a donut-shaped light receiving surface may be provided on the rotor side, and a light irradiation surface that does not cover the entire circumference may be provided on the transmission side of the hub.

  <Embodiment 5 Detailed Configuration Temperature Change Information Recording Unit>

As shown in FIG. 18, the “temperature change information recording unit” 1532 is temperature change information that associates temperature information with the position and measurement time based on the resistance value information acquired from the resistance value acquisition unit 1531 with position. Record.
As the “temperature information”, a difference from a normal temperature measurement value (measurement value before temperature rise by lightning strike: measurement value before lightning strike) of the same sensor (for example, resistance wire for measurement) is used. The measured values before the lightning strike are different in spring, summer, autumn, and winter, but by using the measured values closest to the lightning strike, it is possible to eliminate seasonal fluctuations and time fluctuation errors of the room temperature measured values. Alternatively, calibration information indicating the relationship between the temperature and the resistance value is held, and the difference between the resistance values is calculated using the resistance value when there is no lightning strike at the time of the lightning strike from an external thermometer and used. You may comprise as follows. Lightning strikes are often accompanied by sudden changes in the weather, and sudden changes in the weather can cause sudden changes in the outside air temperature and thus the resistance value of the resistance wire for measurement. Also, if the resistance values and physical properties of all the sensors of all blades are the same, the blades without lightning strikes or the sensor parts without lightning strikes are detected from the blades, and the resistance values of the sensors in those parts are detected at room temperature. It is conceivable to use it as a resistance value. Blades without lightning strikes and sensors without lightning strikes are selected by analyzing resistance changes over time. Alternatively, the resistance values of all the sensors can be collected and the largest resistance value can be selected as the resistance value at room temperature.
The recorded temperature change information may be sent to the monitoring system via the network at all times, or has a separate criterion for determining whether the temperature change information indicates lightning strikes, in light of that criterion. You may comprise so that temperature change information may be transmitted via a network only when it is judged that there was a lightning strike. In this case, it is preferable that the transmission is performed including not only the information after the lightning strike but also the information before the lightning strike. Further, the determination criterion is not limited to a lightning strike, but a lightning strike sign may be judged, and when there is a lightning strike sign, temperature change information of the surrounding time may be transmitted via the network. Note that the time resolution of the temperature change information is preferably about 0.1 to 1 second. This is because lightning strikes occur instantaneously, so accurate down conductor analysis is difficult unless time resolution is high.

  The interface of the temperature change information recording unit 1532 in FIG. 18 will be described. The recording information of the temperature change information recording unit is composed of “date”, “measurement time”, “position in blade”, and “temperature information”. Lightning strike information undergoes a sudden change in temperature information when a lightning strike occurs, and then gradually becomes gentle with time. The temperature change information can be used for the analysis of lightning strike information by recording the information before and after (up and down) at the same time.

<Sixth Embodiment Down Conduct Soundness Detection System Use of Image>
<Embodiment 6 Image Usage Configuration>

  As illustrated in FIG. 19, the down conductor soundness detection system according to the sixth embodiment further includes a “lightning position information acquisition unit” 1933 based on the first to fifth embodiments. The lightning strike position information acquisition unit 1933 is provided in a computer 1907 disposed on the back of the hub 1903.

  <Sixth Embodiment Use of Image Lightning Position Information Acquisition Unit>

  The “lightning position information acquisition unit” 1933 is information associating time information with an image or / and video of a lightning strike on the blade or a wound caused by a lightning strike on the blade, as shown in FIGS. It is configured to obtain lightning position information. This image information is acquired by a camera attached to the upper part, side part, or lower part of the nacelle (attached to the upper part of the nacelle in FIG. 20), or acquired by a camera installed on the ground or on a ground structure different from the windmill. Is done. The camera is preferably configured to always acquire images of all blades, but may be configured to periodically acquire images of each blade. However, it is preferable that the interval time is short. The camera is configured to project the entire image of the blade within the angle of view. This camera is preferably configured so that a clear image can be acquired by changing the aperture or changing the image sensitivity electronically between daytime and night. This camera captures the moment of lightning strikes and, in combination with temperature information, makes it possible to understand the effects of lightning strikes more accurately. This image information may be a moving image, or may be a still image when the interval is short. The image information may be configured to be transmitted to an external monitoring base via a network at all times, or configured to be transmitted only when it is determined that a lightning strike has occurred from temperature information or image information. Also good. Further, it may be designed to perform image analysis. Image analysis is to determine the size, time, current amount, etc. of lightning strikes by image analysis.

The interface of the lightning strike position information acquisition unit 1933 will be described with reference to FIGS. As shown in FIG. 21, the acquisition information of the lightning position information acquisition unit is composed of “blade No.”, “time information”, “scratch image (file name)”, “thumbnail”, or in addition to FIG. It consists of “scratch video (file name)” and its “thumbnail”. As a file format format of the wound image (still image), general standards such as JPEG, Exif, and GIF can be used. As the file format of the wound video (moving image), general standard standards such as MOV, motion JPEG, JPEG2000, MPEG4, MPEG2 and NTSC can be used.
<Embodiment 7 Down conductor soundness detection system Transmission of temperature information and mix information of image information>
<Embodiment 7 Configuration for using mix information>

  As shown in FIG. 23, the down conductor soundness detection system according to the seventh embodiment further includes an “observation information output unit” 2342 based on the first to sixth embodiments.

  <Embodiment 7 Use of mix information Observation information output unit>

  The “observation information output unit” 2342 is configured to output time information input unit 2341 and observation information (FIG. 24) including temperature change information and lightning strike position information based on the input time information. Observation information is used to transmit temperature change information and lightning position information on a common time axis, and since image information and temperature change information with position can be used, more detailed down conductor soundness can be obtained. Can be analyzed.

Here, the observation information output unit 2342 and the time information input unit 2341 constitute an observation unit 2340. The observation unit 2340 is installed in a remote monitoring center 2344 via a control room or network 2343 near or inside the tower. Alternatively, the case where the worker downloads the recording data of the computer 2307 in the nacelle and analyzes it with a maintenance personal computer during maintenance is also included.
<Lightning strike measurement>

  Lightning strike measurement when a lightning strike occurs is described.

  As shown in FIG. 5 (a), during a lightning strike on the blade, a lightning path is connected to the down conductor from the blade surface through the FRP of the blade material. A local temperature rise occurs due to a large current of lightning strike return. FIG. 5B shows a state in which the blade is instantaneously generated during a lightning strike on the blade.

Then, as shown in FIGS. 6A, 6B, and 6C, the local high temperature causes the down-conductor to linearly decrease in the down conductor with time, and the nearby temperature becomes uniform.
<Down conductor soundness detection system>

  As shown in FIG. 7, temperature sensors 0701, 0702, 0703, 0704, 0705, 0706... Are provided along the down conductor, and the temperature sensors are arranged at intervals of 0.5 m, for example. These temperature sensors are provided over substantially the entire length along the down conductor. If one blade is 40 m, if a temperature sensor is arranged every 0.5 m, a measurement position of 80 channels can be secured. However, lightning strikes often hit the tip of the blade. For example, if the blade has a diameter of 40 m, a 10 m temperature sensor array (measurement resistance wire) is used within a quarter of the blade tip. If a temperature sensor is arranged every 0.5 m, 20 channel measurement positions may be secured. In addition, when a plurality of receptors such as the blade tip and the middle are arranged, a temperature sensor is arranged from the receptor and measurement is performed. A line drawn from between the terminals of the temperature sensor is connected to the multiplexer 0710 to form a Wheatstone bridge circuit 0711, and the temperature is measured by switching for each channel of the multiplexer under the control of the computer 0712. These measured temperatures are recorded for each hard disk of the computer. Since the hard disk may crash, it may be stored in another non-volatile memory.

  As shown in FIG. 8, the actual windmill has three blades, and a down conductor soundness detection system is arranged for each blade. For example, in the blade 0801, the down conductor soundness detection system includes a temperature sensor array (measurement resistance line) 0805, a multiplexer 0807, a Wheatstone bridge circuit 0807, and a computer 0808. In the drawing of FIG. 8, the computer 0808 is disposed on the back of the hub. It is pulled out for convenience. Similarly, the blade 802 includes a down-conductor health detection system including a temperature sensor array (measurement resistance line) 0809, a multiplexer 0810, a Wheatstone bridge circuit 0811, and a common computer 0808.

  Further, the blade 803 includes a down-conductor soundness detection system including a temperature sensor array (measurement resistance line) 0812, a multiplexer 0813, a Wheatstone bridge circuit 0814, and a common computer 0808.

  <Temperature measurement method>

  Hereinafter, a method of measuring the temperature by connecting the temperature sensor array in parallel to the down conductor and switching the multiplexer will be described.

  As shown in FIG. 9A, the Wheatstone bridge circuit includes a down conductor (1), a temperature sensor terminal (2), temperature compensation lead terminals (3) and (4), a measurement detection operation amplifier, a driving power source, And a minute change in current is managed by a measured temperature calculation processing / management device (computer).

  As shown in FIG. 9B, a nichrome wire temperature sensor array is connected in parallel to the down conductor, and between the down conductor temperature sensor terminals ((1) to (1) ′ + (2) to (2 The length of) ′) and the length of the temperature compensation lead wire terminals ((3) to (4)) are kept the same for temperature compensation.

  The temperature measurement operation of this parallel system with a temperature sensor array connected in parallel to the down conductor will be described.

As shown in FIG. 10, it is assumed that the measurement is started at T0 = 16: 43: 24: 000. The number of measurements is assumed to scan at T0 = 10 msec intervals.
When T1 = 0 at the first measurement, the rightmost temperature sensor is switched on by switching the multiplexer, and the temperature is measured. The temperature sensors are sequentially shifted one by one, and the temperature measurement is executed in units of 10 msec with T2, T3, T4, T5, and T6.

  Hereinafter, a method of measuring the temperature by connecting the temperature sensor array in series to the down conductor and switching by the multiplexer will be described.

  FIG. 11 is a conceptual diagram of an experimental circuit for temperature measurement of a Nichrome wire temperature sensor array connected in series by combining a Wheatstone bridge circuit and a multiplexer. In the present embodiment, a down conductor soundness detection system is configured with such a simple circuit configuration.

  As shown in FIG. 11, the resistors R1 and R2 have known resistances, the nichrome wire temperature sensor arrays H1, H2, H3... To be measured, and the same length as the conductors between the nichrome wire temperature sensor arrays l1 and l2. The temperature compensating lead wire l1'-l2 'is used. The material of the compensating lead wire is the same as the nichrome wire of the nichrome wire temperature sensor array. Here, using the multiplexers MPX1 and MPX2, the nichrome wire temperature sensor arrays H1, H2, and H3 are sequentially switched to perform temperature measurement. For example, when the length of the blade is 40 m and the measurement range is 1/4 from the tip of the blade (position farthest from the hub), the nichrome wire temperature sensor array is arranged 10 m. If the basic unit length of one array is 0.5 m, the sensor array becomes 20 arrays, and 20 channels of measurement points (positions) can be measured. That is, 20 lightning strike points can be identified by this temperature measurement. Then, the lightning strike location of the blade can be finely positioned, and it is sufficient to cut the blade at the minimum necessary for the maintenance such as determination of the loss level (loss state) and repair / replacement, thereby improving the maintainability of the operator. Further, it is possible to predict or prevent mechanical damage in the windmill blade. In the example described above, 20 channels (locations) are measured at 10 m, but the basic unit length of the sensor array is set to 1 m, 0.4 m, 0.3 m, 0 depending on the lightning characteristics at the installation location of the windmill. .2m, 0, 1m, etc. may be selected arbitrarily.

  Specifically, as shown in FIG. 12, the multiplexer MPX2 of the same type as the 8-channel multiplexer MPX1 has a 16-channel configuration. Channels 0 to 7 correspond to switches 0 to 7 of one multiplexer. Nichrome wire sensor arrays H1, H2, H3, H4, H5, H6, and H7 used a 100 W type, and a temperature measurement test was conducted with an experimental circuit having a DC resistance value of about 100 ohms. In this example, similarly to FIG. 11, a temperature compensating lead wire having the same length as that of the nichrome wire temperature sensor array is used, and the material of the temperature compensating lead wire is also a nichrome wire.

  First, temperature measurement of the nichrome wire sensor arrays H1, H2, and H3 will be described. When the temperature of H1 is measured, it can be measured by turning on CH0 of multiplexer MPX1 and turning on CH1 of multiplexer MPX2. In the case of H2 and H3, measurement can be performed by sequentially switching these two multiplexers. These multiplexers MPX1 and MPX2 are connected to the A6C operation surface, and the temperature can be measured by the operator operating the A6C operation surface.

  As described above, it is possible to perform temperature measurement even if the nichrome wire temperature sensor array is constituted by a series circuit or a parallel circuit with respect to the down conductor.

  For example, when a lightning strike occurs, the maximum temperature at each position of the down conductor can be measured for each lightning strike, so mechanical damage damage prediction using position information can be performed, realizing a down conductor soundness detection system it can. By applying such a soundness detection system to a wind turbine blade, when the wind turbine is used in a wind power generation facility, it is possible to contribute to the safety of the power generation apparatus and the improvement of the operating rate of the wind power generation facility.

  As described above, according to the first to eighth embodiments, it is possible to provide the wind turbine having the down conductor soundness detection system that can measure the maximum temperature at each position of the down conductor for each lightning strike. In addition, it is possible to provide a wind turbine having a down conductor soundness detection system that improves the maintainability of the down conductor.

Claims (8)

A hub,
Multiple blades supported by a hub;
A rotor shaft that pivotally supports the hub;
A nacelle for storing the rotor shaft,
A tower that supports the nacelle,
Consists of
For each blade,
A receptor, and a down conductor provided from the receptor to the hub;
A wind turbine having a down conductor health detection system including a sensor array including a plurality of temperature sensors arranged in parallel and continuously over substantially the entire length of the down conductor. The wind turbine having the down-conductor health detection system according to claim 1, wherein each sensor of the sensor array of the down-conductor health detection system uses a resistance wire for measurement for acquiring temperature information as a temperature sensor. The wind turbine having the down conductor soundness detection system according to claim 1 or 2, wherein the sensor array is housed in an insulating sheath in a blade. The wind turbine having the down conductor soundness detection system according to claim 3, wherein the insulating sheath is housed in a flexible metal hose. The down conductor health detection system includes:
Positioned resistance value acquisition unit that acquires the resistance value information of the resistance wire for measurement in association with the position in the blade, and temperature information based on the resistance value information acquired from the positioned resistance value acquisition unit, the position and the measurement time The windmill which has a down conductor soundness detection system as described in any one of Claim 2 to 4 which further has a temperature change information recording part recorded as temperature change information which is the information linked | related to (5). The down conductor health detection system includes:
3. A lightning strike position information acquisition unit for acquiring lightning strike position information, which is information associating a lightning strike on the blade or an image or / and video of a wound caused by a lightning strike on the blade with time information. A wind turbine having the down conductor soundness detection system according to claim 5. The down conductor health detection system includes:
The down-conductor health detection system according to claim 6, further comprising: a time information input unit; and an observation information output unit that outputs observation information including temperature change information and lightning strike position information based on the input time information. Having a windmill.   The down conductor soundness detection system according to claim 1.

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