problem 1:

a) What is thermal breakdown in solid dielectric? How is it practically more important than other methods?

b) A solid specimen of dielectric consists of a dielectric constant of 4.2, and tan = 0.0001 at a frequency of 50 Hz. If it is subjected to an alternating field of 50 kV/cm, compute the heat generated in the specimen due to the dielectric loss.

problem 2: Give the temperature classification of solid insulating materials. Why is this categorization not done for liquids and gases?

problem 3:

a) Describe the properties and applications of Fiber solid dielectric materials used in practice in the high voltage engineering.

b) Describe about the avalanche breakdown in solid dielectric material.

problem 4: Describe the different method by which break down in solid dielectrics in practice.

problem 5:

a) describe the method of short-term breakdown of composite solid insulating material.

b) A coaxial cylindrical capacitor is to be designed with an effective length of 20 cm. The capacitor is expected to have a capacitor of 1000 pF and to operate at 150 kHz. Choose an appropriate insulating material and give the dimensions of the electrode.