Course Details

Subject {L-T-P / C} : EE6249 : Partial Discharges in Power System Equipments { 3-0-0 / 3}

Subject Nature : Theory

Coordinator : Prof. Subrata Karmakar

Syllabus

The Phenomenon of Partial Discharge (PD): Introduction, Definition of terms, typical electrode configurations with PD, internal discharges and surface discharges, external discharges, equivalent circuits, PD characteristics of parameters, waveform and characteristics of an individual PD pulse, train of PD current pulses, train of PD pulses in relation to the temporarily assigned instantaneous value of the high voltage, non electrical PD characteristics parameters. Fundamentals of PD Measuring Techniques: Wave form and spectrum of PD, PD charge measuring equipments, integration in the frequency domain, selectively wide band system, narrow band system, integration in the time domain with very large wide band systems, measuring impedance or coupling 4 terminal device, PD measuring circuits, calibration, calibration pulses, calibration of PD measuring setup, calibration of the complete test set up, uncertainty of measurements. Screening and Filtering Problems during Partial Discharge Measurements: Need for screening, design of screens, completely enclosed screen, screen interruptions, effect of corners, cavity resonance, design of filters, measurement of screening efficiency, lead through bushings. Effects of PD on Electrical Insulating Materials: Effects of PD on gaseous insulating materials, liquid insulating materials, solid insulating materials, surface discharges, internal discharges, mixed dielectrics. Evaluation of PD: Relation between measured and actual charge, relation between the time-dependent occurrence of PD, and the extent of damage due to it. Measurement and Location of PD: Need for PD measurement, Development of PD measurement technique in cables, problems during PD measurements on long cables, reflection and superposition effects.

Course Objectives

Course Outcomes

1. Students can understand the basic concepts of Partial Discharge (PD) in power system equipment. <br />2. Students can understand the different detection technique of PD. <br />3. Students can analyze the filtering problems during PD measurements. <br />4. Student will understand the effects of PD on electrical insulating materials. <br />5. To understand the fundamental requirements for evaluation of PD. <br />6. Students will understand the measurements and identify the location of PD.

Essential Reading

Supplementary Reading