Sains Malaysiana 44(12)(2015): 1701–1706

Radar Return Reduction for Wind Turbines using Bump Structures

(Pengurangan Radar Pantulan Gelombang untuk Kincir Angin Menggunakan Struktur Bonggol)

SHYH-KUANG UENG*¹ & YAO-HONG CHAN¹, WEI-HSIEN LU² & HENG-WEN CHANG²

¹Department of Computer Science & Engineering, National Taiwan Ocean University, Keelung City 202, Taiwan

²Green Energy and Environment Research Laboratories, ITRI, Chung Hsin Rd., Chutung, Hsinchu, Taiwan

Received: 11 August 2014/Accepted: 23 June 2015

ABSTRACT

Wind turbines are massive electrical structures. They produce large returns when illuminated by radar waves. These scatterings have a great impact on the operation of surveillance, air traffic control and weather radars. This paper presents two geometric modelling methods for reshaping wind turbine towers so that the Radar Cross Section (RCS) of wind turbines is reduced. In the proposed reshaping methods, bump structures are created on the surface of the conventional cylinder wind turbine tower. When a reshaped tower is illuminated by radar waves, the bump structures scatter incident radar waves into insignificant directions so that the strength of back-scattering is declined and the RCS of the wind turbine is decreased. The test results confirmed that the proposed methods significantly reduce bi-static RCS values of wind turbines. The proposed reshaping methods are practical, flexible and effective in alleviating the scatterings of wind turbines.

Keywords: Radar cross section; reshaping method; stealthy technology; wind turbine

ABSTRAK

Kincir angin merupakan struktur elektrik yang besar. Ia menghasilkan pantulan gelombang radar yang besar apabila dipancarkan. Taburan ini memberi kesan yang besar terhadap operasi pengawasan, kawalan trafik udara dan radar udara. Kajian ini menjelaskan dua kaedah pemodelan geometri untuk rekaan semula bentuk menara kincir angin supaya Keratan Rentas Radar (RCS) angin dikurangkan. Dalam kaedah yang dicadangkan, struktur bonggol diletakkan di atas permukaan silinder menara kincir angin biasa. Apabila menara kincir angin dipancarkan dengan gelombang radar, bonggol menyelerakkan gelombang tersebut ke pelbagai arah. Jadi kekuatan serakan balik berkurang dan keratan rentas radar kincir angin turut berkurang. Hasil ujian menunjukkan, keratan rentas radar dwi-statik kincir angin telah dikurangkan dengan banyak. Kaedah ini adalah praktikal, fleksibel dan efektif bagi mengurangkan serakan balik kincir angin.

Kata kunci: Kaedah pembentukan semula; keratan rentas radar; kincir angin; teknologi stealthy

REFERENCES

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*Corresponding author; email: skueng@mail.ntou.edu.tw