Size determination of contaminants in HV XLPE cable insulation with holographic technique

A Fraunhofer far-field holographic technique has been used to develop a method which allows the size of particles of contaminants in an HV XLPE (high-voltage cross-linked polyethylene) cable insulating layer to be determined without cutting it into thin slices. The cable samples can be as thick as 4.0 cm when a resolution of 50 mu m is achieved. The accuracy of the proposed method is within 10% for particles larger than 20 mu m in diameter.<
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