Physic of Dielectrics

Garant předmětu:

Pavel Mach

Lecturer:

Pavel Mach

Tutor:

Pavel Mach

Supervisor:

Department of Electrotechnology

Synopsis:

Types and mechanizmus of polarization. Dielectric absorption. Electrical conductivity of insulators. Dielectrics in static electrical field. Dielectrics in time-dependent electrical field. Frequency dispersion of polymers. Thermal dispersion of polymers. Optical properties of dielectrics. Dielectrics losses. Electrical strength of insulators. Electrical properties of thin dielectrics films. Ageing of insulators. Properties of feroelectrics. Main and joined phenomena in dielectrics.

Requirements:

The student must first obtain a credit and only then can apply for the exam. Assesment methods and criteria linked to learning outcomes: Conditions for the course-unit credit: active participation in seminars and elaboration and defense of individual work.

Syllabus of lectures:

1. Introduction into the physics of dielectrics. Permanent and induced. Types of polarization.

2. Polarization and dielectric constant.

3. Dipole moments. Polarizability. Polarization and energy. Internal field.

4. Non-polar dielectrics. Lorentz's field. Clausius-Massotti equation.

5. Polarization in gases. The dielectric properties of gases.

6. Polarization in liquids. The dielectric properties of liquids.

7. Polarization in solids chosen. The dielectric properties of solids.

8. The dielectric relaxation theory. Frequency and Time Domain.

9. The complex dielectric permittivity. Dielectric losses and dispersion. Cole-Cole diagram.

10. Frequency and temperature dispersion of polymers.

11. Electrical strength of insulators - gases, liquids, solids.

12. Manufacturing and electrical properties of thin ceramic films.

13. Ferroelectrics and their dielectric properties. Curie-Weiss law.

14. Aging of dielectrics.

Syllabus of tutorials:

1. Introduction to laboratory tasks. Safety.

2. Measurement of non-polar dielectric properties in dependence on temperature.

3. Measurement of polar dielectric properties in dependence on temperature.

4. Measurement of non-polar dielectric properties in dependence on frequency.

5. Measurement of polar dielectric properties in dependence on frequency.

6. Curie temperature determination for polar dielectrics.

7. Measurement of polar dielectric properties over Curie temperature.

8.-12. Assignment of individual work.

13. Presentation and defense of individual work.

14. Assessment.

Study Objective:

Students will acquire basic information about dielectric materials for electrical engineering. It will deal with the behavior of dielectrics in both static and electrical fields, polarizations, losses in dielectrics and types of dielectrics by state and type of polarization. It also obtains information about thin dielectric layers and about dielectric aging.

Study materials:

[1] Tillar Shugg: Handbook of Electrical and Electronic Insulating Materials, IEEE Press, New York, 1996

[2] Gorur G. Raju: Dielectrics in Electric Fields, ISBN 0824708644, CRC, 2003

Note:

Further information:

http://www.fel.cvut.cz/education/bk/predmety/11/84/p11849504.html

Time-table for winter semester 2024/2025:

	06:00–08:0008:00–10:0010:00–12:0012:00–14:0014:00–16:0016:00–18:0018:00–20:0020:00–22:0022:00–24:00
Mon
Tue
Wed	roomT2:C4-264 Mach P. 12:45–14:15 (lecture parallel1 parallel nr.1) Dejvice Laborator 264
Thu
Fri	roomT2:C4-264 Mach P. 11:00–12:30 (lecture parallel1) Dejvice Laborator 264

Time-table for summer semester 2024/2025:

Time-table is not available yet

The course is a part of the following study plans:

• Doctoral studies, daily studies (compulsory elective course)
• Doctoral studies, combined studies (compulsory elective course)
• Doctoral studies, structured daily studies (compulsory elective course)
• Doctoral studies, structured combined studies (compulsory elective course)