JP2012164446A - Lightning damage countermeasure device of high-rise building structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel lightning damage countermeasure device of a wind-force power generation facility capable of predicting lightning before generation of thunder and reducing probability of direct hit of the lightning to windmill blades.SOLUTION: The device includes: a polarity detection means detecting polarity of thunder cloud; a voltage application means applying voltage with the polarity same as that of the thunder cloud onto windmill blades constituting part of the wind-force power generation facility; and a voltage inversion means reversing the polarity of the voltage applied to the windmill blades within 100 ms after lightning discharge.

Description

  The present invention relates to a lightning damage countermeasure device for a high-rise building, and more particularly to a lightning damage countermeasure device for a wind power generation facility.

  In recent years, wind power generators have increased in size and capacity, and the ground clearance has reached 100 m or more. There are reports of lightning strikes on wind power generator blades around the world. The main damage is windmill blade breakage, generator and gearbox damage. As measures against this, development of a technique for receiving lightning with a windmill blade and flowing it to the ground, analysis of lightning strikes on the windmill blade, and improvement of grounding are performed (for example, see Patent Document 1). .

  As a conventional lightning damage countermeasure, for example, a method is known in which a lightning rod is installed in a wind power generator, and lightning is received by the lightning rod and discharged to the ground through the main pillar. However, since the windmill blade protrudes above the lightning rod, there is a problem that lightning strikes the blade frequently. There is also known a method in which a metal circular plate is arranged as a receptor near the tip of the windmill blade, and light is received by the receptor and discharged to the ground through the main pillar. However, there was a risk of the gearbox and generator being destroyed by a large current of lightning. Further, since the receptor is damaged by lightning, there is a drawback that it is necessary to replace the receptor.

  In general, countermeasures against lightning strikes are effective as countermeasures against lightning strikes, as well as countermeasures for lightning strikes as described above. Conventionally, the occurrence of lightning has been observed by lightning strikes such as satellite images, and lightning predictions have been made in each region based on the speed of thunderclouds. However, the possibility of lightning strikes differs depending on the terrain and the type and size of buildings, and there is a problem that lightning strikes cannot be predicted unless lightning occurs.

JP 2010-223148 A

  Therefore, the present invention provides a lightning damage countermeasure device for a new wind power generation facility that solves the above problems, predicts lightning strikes before lightning occurs, and can reduce the probability of direct lightning strikes on windmill blades. It is an object of the present invention to provide a lightning damage countermeasure device for a general high-rise building that is not limited to wind power generation facilities and is easily damaged by lightning.

  A lightning damage countermeasure device for a high-rise building according to claim 1 of the present invention applies polarity detection means for detecting the polarity of a thundercloud and a voltage having the same polarity as that of a thundercloud to a structure constituting a part of the high-rise building. It is characterized by comprising voltage applying means and voltage inverting means for inverting the polarity of the voltage applied to the structure within 100 ms after lightning discharge.

  The lightning damage countermeasure device for a high-rise building according to claim 2 of the present invention is the wind power generation facility according to claim 1, wherein the high-rise building is a wind turbine blade, a generator, a wind turbine main pillar, and the structure is It is a windmill blade, This windmill blade is electrically insulated from the said generator, It is characterized by the above-mentioned.

  The lightning damage countermeasure device for a high-rise building according to claim 3 of the present invention is the lightning damage countermeasure device according to claim 2, wherein the polarity detecting means measures a potential difference between the ground surface and a tip portion of the wind turbine main pillar, and the voltage applying means is The voltage difference is applied when the potential difference exceeds a predetermined value.

  According to the lightning damage countermeasure device for a high-rise building according to claim 1 of the present invention, the polarity of the thundercloud is detected by the polarity detection means, and the structure constituting a part of the high-rise building is the same as the thundercloud by the voltage application means. By applying a voltage of polarity, the probability of a direct lightning strike to the structure can be reduced. In addition, by reversing the polarity of the voltage applied to the structure by the voltage inverting means within 100 ms after the lightning discharge, it is possible to cope with the return lightning strike.

  According to the lightning damage countermeasure device for a high-rise building according to claim 2 of the present invention, it is possible to reduce the probability of a direct lightning strike to the windmill blade of the wind power generator.

  According to the lightning damage countermeasure device for a high-rise building according to claim 3 of the present invention, by applying a voltage when the potential difference between the ground surface and the tip of the wind turbine main column exceeds a predetermined value, lightning can be generated. Lightning strikes can be predicted before they occur, reducing the probability of direct lightning strikes on windmill blades.

  The lightning damage countermeasure device for a high-rise building of the present invention will be described below by taking a lightning damage countermeasure device for a wind power generation facility as an example. In addition, this invention is not limited to a following example, A various deformation | transformation implementation is possible.

  The lightning damage countermeasure device of the wind power generation facility of this embodiment performs shielding (electric field relaxation) against lightning by applying a voltage having the same polarity as the thundercloud to the windmill blade of the wind power generation device, and lightning strikes to the wind power generation device. It is a device for reducing the direct hit probability. And the lightning damage countermeasure device of the wind power generation facility of the present embodiment, the polarity detection means for detecting the polarity of the thundercloud, and the voltage application for applying the same polarity voltage as the thundercloud to the windmill blade constituting a part of the wind power generation device And voltage inversion means for inverting the polarity of the voltage applied to the windmill blade within 100 ms after lightning discharge.

  The wind turbine generator in which the lightning damage countermeasure device of the wind turbine generator according to this embodiment is installed includes a wind turbine blade, a generator, and a wind turbine main pillar. A generator is provided at the tip of the wind turbine support, and the rotational force generated by the wind turbine blades receiving the wind is transmitted to the generator to generate power. In addition, since it is necessary to apply a voltage to the windmill blade, the windmill blade is electrically insulated from the generator by arranging a gear or a gear made of an insulating material such as ceramics at a connection portion between the windmill blade and the generator. Has been.

  The polarity detection means measures the potential difference between the ground surface and the tip of the wind turbine main column, and the voltage application means applies a voltage to the wind turbine blade when the potential difference exceeds a predetermined value, and the wind turbine blade is the same as the thunder cloud. It is comprised so that it may charge to polarity. When the voltage applied to the windmill blade is too high, a corona discharge is generated and a local discharge is likely to occur. Therefore, a potential of about 4 to 6 kV DC is generated at the tip of the windmill blade. It is preferable to apply. By applying a voltage when the potential difference between the ground surface and the tip of the wind turbine main column exceeds a predetermined value, a lightning strike is predicted before lightning occurs, and the direct lightning strike probability to the windmill blade is determined. It can be reduced. On the other hand, no voltage is applied when the potential difference between the ground surface and the tip of the wind turbine main column is not more than a predetermined value. The polarity detection means and the voltage application means can be easily configured by conventional techniques.

  In addition, a phenomenon is known in which lightning discharge with reverse polarity occurs about 150 ms after lightning discharge. This is a phenomenon in which the polarity of the thundercloud is reversed by the first lightning discharge and a reverse current flows, and this reverse polarity lightning discharge is called a return lightning stroke. In order to cope with this return lightning strike, the voltage reversing means reverses the polarity of the voltage applied to the windmill blade within 100 ms after the lightning discharge when the polarity detecting means detects that the polarity of the thundercloud has been reversed. It is configured. That is, when the polarity of the thundercloud is reversed, the polarity of the voltage at the tip of the windmill blade is reversed within 100 ms after the lightning discharge. On the other hand, when the polarity of the thundercloud does not reverse after lightning discharge, the voltage reversing means does not operate. Note that the voltage inverting means can be easily configured in a circuit according to the prior art.

  In recent years, FRP (glass fiber reinforced plastic) has been used as the material of the windmill blade, and it is conceivable that the conductivity, that is, the voltage propagation speed becomes slow. Therefore, an experiment was attempted in which a voltage of about 3 kV was applied to a piece of wood having a length of about 20 cm.

  A rectifier circuit composed of a neon transformer (AC 0 to 15 kV), a diode, and a capacitor was made, and a high voltage of about 3 kV DC was applied to one end of the wood piece by adjusting the voltage. When the other piece of wood was observed with a non-contact electrostatic voltmeter, a voltage application of about 2.5 kV was observed.

  In an actual windmill blade, moisture, salt, etc. are attached, and there is a high possibility of wetting when a thundercloud is generated. For this reason, it is thought that the resistivity of the material which influences a voltage propagation speed becomes below a wood piece.

Claims (3)

Polarity detection means for detecting the polarity of thunderclouds, voltage application means for applying a voltage having the same polarity as that of a thundercloud to a structure constituting a part of a high-rise building, and lightning discharge of the polarity of the voltage applied to the structure A lightning damage countermeasure device for a high-rise building, comprising voltage reversing means for reversing within 100 ms. The high-rise building is a wind turbine generator including a wind turbine blade, a generator, and a wind turbine main pillar, and the structure is a wind turbine blade, and the wind turbine blade is electrically insulated from the generator. The lightning damage countermeasure device for high-rise buildings according to claim 1. The polarity detection means measures a potential difference between the ground surface and the tip of the wind turbine main pillar, and the voltage application means is configured to apply a voltage when the potential difference exceeds a predetermined value. The lightning damage countermeasure apparatus for high-rise buildings according to claim 2.