SCHOOL

Engineering

ACADEMIC UNIT

Electrical and Computer Engineering

LEVEL OF STUDIES

8

COURSE CODE

ECE_BΚ803

SEMESTER

8

COURSE TITLE

Tests and Measurements of High Voltages

INDEPENDENT TEACHING ACTIVITIES
if credits are awarded for separate components of the course, e.g. lectures, laboratory exercises, etc. If the credits are awarded for the whole of the course, give the weekly teaching hours and the total credits

WEEKLY TEACHING HOURS

CREDITS

Lectures.

3

5

Problem solving.

Laboratory.

3

Add rows if necessary. The organisation of teaching and the teaching methods used are described in detail at (d).

COURSE TYPE

general background,
special background, specialised general knowledge, skills development

Specialized general knowledge.

PREREQUISITE COURSES:

Fundamental knowledge on electrical circuits and measurements, electromagnetism and physics of solid state of matter is desirable.

LANGUAGE OF INSTRUCTION and EXAMINATIONS:

Greek. There is however possibility for tutorials in English and French for foreign students.

IS THE COURSE OFFERED TO ERASMUS STUDENTS

YES.

COURSE WEBSITE (URL)

https://eclass.upatras.gr/courses/EE792/

Introduction: generation and transmission of electric energy, voltage stresses, testing voltages (testing with power frequency voltages, testing with lightning impulse voltages, testing with switching impulses, D.C. voltages, testing with very low frequency voltage).

Generation of high voltages: direct voltages (A.C. to D.C. conversion, electrostatic generators), alternating voltages (testing transformers, series resonant circuits), impulse voltages (impulse voltage generator circuits, operation, design and construction of impulse generators), control systems.

Μeasurement of high voltages: peak voltage measurements by spark gaps (sphere gaps, reference measuring systems, uniform field gaps, rod gaps), electrostatic voltmeters, ammeter in series with high ohmic resistors and high ohmic resistor voltage dividers, generating voltmeters and field sensors, the measurement of peak voltages (the Chubb-Fortescue method, voltage dividers and passive rectifier circuits, active peak-reading circuits, high-voltage capacitors for measuring circuits), voltage dividing systems and impulse voltage measurements (generalized voltage generation and measuring circuit, demands upon transfer characteristics of the measuring system, fundamentals for the computation of the measuring system, voltage dividers, interaction between voltage divider and its lead, the divider’s low-voltage arm), fast digital transient recorders for impulse measurements (principles and historical development of transient digital recorders, errors inherent in digital recorders, specification of ideal A/D recorder and parameters required for h.v. impulse testing, future trends). 

Non-destructive insulation test techniques: dynamic properties of dielectrics (dynamic properties in the time domain, dynamic properties in the frequency domain, modelling of dielectric properties, applications to insulation ageing), dielectric loss and capacitance measurements (the Schering bridge, current comparator bridges, loss measurement on complete equipment, null detectors), partial-discharge measurements (the basic PD test circuit, PD currents, PD measuring systems within the PD test circuit, measuring systems for apparent charge, sources and reduction of disturbances, other PD quantities, calibration of PD detectors in a complete test circuit, digital PD instruments and measurements).

Laboratory exercises:

1) Familiarization with the area and special features of the High Voltage Laboratory – Setups, Instrumentation, Safety and EMC Issues.

2) Generation and measurement of DC, AC and impulse high voltages.

3) Air gaps with emphasis on sphere gaps.

4) Standard tests with emphasis on dielectric oils.

5) Non-destructive tests: Schering and Glynne bridges.

6) Non-destructive tests: standard setups for partial discharge recording.

Introduction: generation and transmission of electric energy, voltage stresses, testing voltages (testing with power frequency voltages, testing with lightning impulse voltages, testing with switching impulses, D.C. voltages, testing with very low frequency voltage).

Generation of high voltages: direct voltages (A.C. to D.C. conversion, electrostatic generators), alternating voltages (testing transformers, series resonant circuits), impulse voltages (impulse voltage generator circuits, operation, design and construction of impulse generators), control systems.

Μeasurement of high voltages: peak voltage measurements by spark gaps (sphere gaps, reference measuring systems, uniform field gaps, rod gaps), electrostatic voltmeters, ammeter in series with high ohmic resistors and high ohmic resistor voltage dividers, generating voltmeters and field sensors, the measurement of peak voltages (the Chubb-Fortescue method, voltage dividers and passive rectifier circuits, active peak-reading circuits, high-voltage capacitors for measuring circuits), voltage dividing systems and impulse voltage measurements (generalized voltage generation and measuring circuit, demands upon transfer characteristics of the measuring system, fundamentals for the computation of the measuring system, voltage dividers, interaction between voltage divider and its lead, the divider’s low-voltage arm), fast digital transient recorders for impulse measurements (principles and historical development of transient digital recorders, errors inherent in digital recorders, specification of ideal A/D recorder and parameters required for h.v. impulse testing, future trends). 

Non-destructive insulation test techniques: dynamic properties of dielectrics (dynamic properties in the time domain, dynamic properties in the frequency domain, modelling of dielectric properties, applications to insulation ageing), dielectric loss and capacitance measurements (the Schering bridge, current comparator bridges, loss measurement on complete equipment, null detectors), partial-discharge measurements (the basic PD test circuit, PD currents, PD measuring systems within the PD test circuit, measuring systems for apparent charge, sources and reduction of disturbances, other PD quantities, calibration of PD detectors in a complete test circuit, digital PD instruments and measurements).

Laboratory exercises:

1) Familiarization with the area and special features of the High Voltage Laboratory – Setups, Instrumentation, Safety and EMC Issues.

2) Generation and measurement of DC, AC and impulse high voltages.

3) Air gaps with emphasis on sphere gaps.

4) Standard tests with emphasis on dielectric oils.

5) Non-destructive tests: Schering and Glynne bridges.

6) Non-destructive tests: standard setups for partial discharge recording.

DELIVERY
Face-to-face, Distance learning, etc.

Face-to-face.

USE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY
Use of ICT in teaching, laboratory education, communication with students

Slide projection, explicating video projection, virtual experiments, small experiment demonstration and use of electronic class. 

TEACHING METHODS

The manner and methods of teaching are described in detail.

Lectures, seminars, laboratory practice, fieldwork, study and analysis of bibliography, tutorials, placements, clinical practice, art workshop, interactive teaching, educational visits, project, essay writing, artistic creativity, etc.

The student's study hours for each learning activity are given as well as the hours of non-directed study according to the principles of the ECTS

STUDENT PERFORMANCE EVALUATION

Description of the evaluation procedure

Language of evaluation, methods of evaluation, summative or conclusive, multiple choice questionnaires, short-answer questions, open-ended questions, problem solving, written work, essay/report, oral examination, public presentation, laboratory work, clinical examination of patient, art interpretation, other

Specifically-defined evaluation criteria are given, and if and where they are accessible to students.

Student evaluation is carried out with a three-hour written examination in Greek language (English or French for foreign students). This examination counts for the 70% of the final grade (if the score is higher than 5.0 out of 10.0). The rest 30% refers to the weighting factor of the laboratory grade (if the score is higher than 5.0 out of 10.0). The latter is determined by the oral examination during each laboratory exercise and the corresponding personal written report.  

- Suggested bibliography:

E. Kuffel, W.S. Zaengl, J. Kuffel, High Voltage Engineering: Fundamentals, Elsevier (2000)

M.S. Naidu, V. Kamaraju, High Voltage Engineering, McGraw Hill (1996) 

- Related academic journals:

The library of the High Voltage Laboratory is continuously updated in respect with the international bibliography (books and journals) and it is available to students.