Question

Briefly answer the following questions: (a) (i) (ii) 15 marks] The cause of ageing in electrical insulation and comment on various (ii) 15 marksl The standard circuit for partial discharge (PD) measurement is shown in 15 marks] The methods available for testing the insulation integrity of high voltage equipment approaches to condition monitoring of power system equipment. Figure 3. Here, C represents the capacitance of the test specimen. Ck is the coupling (blocking) capacitor which is in series with the measuring impedance Z. Explain how the circuit works. Comment on the choice of Ck value in relations to C and Z. Also, carefully explain how PD calibration is carried out. Amplifier Figure 3

Answer 1

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