報告書番号

H04013

タイトル（和文）

縮小モデル実験による風力発電システム雷撃時の過電圧の検討

タイトル（英文）

A Study of Lightning Overvoltages in Wind Power Generation Systems by Means of Reduced-Size Model Experiments

概要 （図表や脚注は「報告書全文」に掲載しております）

本報告書は，最近問題となっている風力発電システムの雷害問題のうち雷サージ波頭部に発生する過電圧について，風車実機の3/100ミニチュアモデルを用いて検討した結果を述べている。過電圧発生のメカニズムを解明するとともに，(1)塔脚の電位が上昇し塔脚と連系線の間に大きな電位差が発生する可能性があること，(2)タワー内に設置された主回路や制御回路がループを形成する場合にはそこに電磁誘導が発生することを明らかとしている。

概要 （英文）

Wind power generation systems are built at locations where few tall structures are found nearby so as to obtain good wind conditions, and thus, they are often struck by lightning. To promote wind power generation, lightning-protection methodologies for such wind power generation systems have to be established. This report presents the result of an experimental study of lightning overvoltages in wind power generation systems using a reduced-size wind turbine model. Overvoltages observed at wavefronts of lightning surges are focused on in this study. In the experiments, lightning strokes to one of the blades and to the nacelle were considered, and voltages and currents at various positions of the wind turbine model were measured. The following points have been deduced from the results: (i) The voltage rise due to the tower footing resistance can cause a significant voltage difference between the tower foot and an incoming conductor led from a distant point. Also, a voltage difference between the bottom of down conductors installed inside the tower and an incoming conductor can be of significance. (ii) The lightning current flowing through the tower body induces voltages in main and control circuits which form loops, and the induced voltages can cause overvoltages and malfunctions. (iii) Traveling-wave phenomena in a wind power generation system for a lightning strike to the tip of a blade and to the nacelle have been made clear from the measured waveforms. This information can be used for developing an EMTP simulation model of wind power generation systems.

報告者

キーワード