Physical Fundamentals of Electric Apparatus

Lecturer:

Tutor:

Supervisor:

Department of Electric Drives and Traction

Synopsis:

Physical basis of switching arc. Switching arcs in DC and AC devices. Interaction between switching apparatus and interrupting circuits. Switching-off capabilities of switches. Switching-off problems of DC and AC devices. Theory of fuses. Basic circuit protection. Over-voltage, limiting elements. Theory of contacts. Contacts models. Special switching systems. Testing of electrical devices.

Requirements:

Syllabus of lectures:

1. Physical basis of switching arc. Arc theory

2. Short and long arc in circuit breakers

3. Arc in air, oil, SF6. Vacuum arc

4. Switching-off capabilities

5. Interaction between switching devices and interrupting circuits

6. DC circuit breakers

7. AC circuit breakers

8. Theory of fuses

9. Over-voltage, limiting devices

10. Theory of contacts

11. Contacts models

12. Special switching systems

13. Network switching conditions

14. Short-circuit tests. Synthetic tests

Syllabus of tutorials:

1. Introduction

2. Interruption DC circuits

3. Interruption DC circuits

4. Interruption AC circuits

5. Interruption AC circuits

6. Recovery voltage, modeling, calculating

7. Vacuum circuit breaker

8. Control test

9. Heat transfer in fuses

10. Heat transfer in fuses

11. Testing of fuses

12. Testing of fuses

13. AC magnets

14. AC magnets. Assessement

Study Objective:

Study materials:

1. Cassie: Introduction to the Theory of Circuit Interruption Circuit Breaking. London 1953

2. Ragaller: Current Interruption in HV Networks. McGraw - Hill, 1978

3. Flurscheim: Power Circuit Breaker Theory and Design. IEE, 1985

Note:

Further information:

No time-table has been prepared for this course

The course is a part of the following study plans: