Getah silikon (SiR) adalah satu jenis bahan polimer yang kebiasaannya digunakan sebagai penebat pepejal di dalam kabel terutamanya untuk penebat pengakhir dan penebat penyambungan dua kabel. Walaubagaimanapun, penebat kabel mudah terdedah terhadap mendapan jika kabel itu telah rosak selepas pemasangan. Ini menyebabkan terjadinya pokok air ketika voltan tinggi dikenakan. Pembangunan pokok air bertambah buruk apabila wujudnya benjolan mikro di permukaan pengalir. Satu eksperimen telah dibangunan untuk melihat kaitan antara pokok air dan benjolan mikro serta kesan mereka terhadap bahan penebat. Pembangunan eksperimen ini menyediakan dua jenis sampel percubaan iaitu sampel tajam dan sampel tumpul. Istilah tajam dan tumpul sampel merujuk kepada bentuk hujung elektrod dimana mereka menyerupai benjolan mikro yang wujud dipermukaan pengalir. Tambahan lagi, elektrod ini telah didedahkan dengan rumusan cecair garam yang bertindak sebagai bahan mendapan tercemar. Ketika percubaan kedua-dua jenis sampel telah disambung voltan tinggi iaitu 10kV. Keputusannya, fenomena pokok air dapat dilihat di kedua-dua sampel. Walaupun begitu, bentuk yang dihasilkan sangat berbeza dari segi panjang dan formasi. Secara umum, permukaan jejari hujung elektrod mempengaruhi kekuatan medan elektrik. Sampel tajam mendahului dalam formasi pokok air kerana ia menghasilkan medan elektrik yang lebih kuat dan luas.
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Silicone rubber (SiR) is a common polymeric material that has been used as solid insulation in cable especially for end termination and two cable connection insulation. However, cable insulator is easily expose to moisture if the cable is defected after installation. This causing water tree to be produced whenever high voltage is applied. Water tree development worsen when there are micro protrusions exist at the conductor’s surface. An experiment is developed in order to observe the relation between water tree and micro protrusion and their effect toward insulation material. This experimental development has prepared two types of sample testing which are sharp and blunt sample. These sharp and blunt sample are referred to the shape of electrode tip resemble the micro protrusion appear on the conductor’s surface. Furthermore, the electrode is exposed to salt solution that act as a moisture contaminant. During testing both sample are connected to high voltage which is 10kV. As a result, water tree phenomenon can be seen on both sample. However, the shape produced is very differently in term of length and formation. In general, surface radius of the electrode tip influenced the strength of electrical field intensity. Sharp sample precede in water tree formation because it produces stronger and larger area of electrical field.
Investigation of water treeing development in silicone rubber under the influence of high voltage / Mohamad Ikhmal Fitri Noorizan