Course detail

Substations and Lines

FEKT-LESVAcad. year: 2017/2018

Description of basic parts and accessories of electrical substations. The operation, design and protection of transformers. Earthing system of switchgears and transformer substations. Substation automation system. Theory of thermal and mechanical stress of conductors due to operating loads and short-circuits. Theory of mechanical stress of unsymmetrical hanging conductor under the given climatic conditions. Practical experience, students will gain by working on supply transformer station project and also in laboratory exercises, where they verify the correct setting of transformer differential protection or blocking of apparatus by means of the substation simulator.

Learning outcomes of the course unit

Graduates of this course should be able to
- characterize the basic types of electrical susbstation,
- apply appropriate arrangement of busbar systems of switchgear in the electrical substation project,
- select the appropriate power output and power transformers for substation,
- apply the basic interlocking conditions for the blocking of individual devices in switchgears branches,
- distinguish the devices in individual level of substation automation system,
- describe and explain the transformer protection system,
- calculate the setting of transformer differential protection,
- check power line according to thermal and dynamic effects of short-circuit current,
- design a grounding of transformer station according to the required earthing resistance.


The basic knowledge of the design of power lines, schemes and versions of switchgears in electrical substation are required. Students registered in the course should be able to describe and explain the principles of operation and equivalent circuit of transformer. Their orientation in the basic principles of functional types of protection is assumed. General knowledge is required at the level of bachelor's degree, but it is advisable to have completed courses Electrical Power Distribution and Distribution Equipment.


Not applicable.

Recommended optional programme components

Not applicable.

Recommended or required reading

Not applicable.

Planned learning activities and teaching methods

Techning methods include lectures, computer laboratories and practical laboratories. Course is taking advantage of e-learning (Moodle) system. Students have to write two projects/assignments during the course.

Assesment methods and criteria linked to learning outcomes

Students can obtain up to 50 points of the overall evaluation of the course during the semester - 20 points for projects up to 10 points for the processing of laboratory protocols and 20 points in the final test. A student has to obtain at least half of the maximum points in all mentioned activities.
The final exam is oral (max. 50 points). It focuses on the orientation in the topics as are defined in course syllabus. The condition for the successful passing this exam is to get at least half of the maximum points

Language of instruction


Work placements

Not applicable.

Course curriculum

1. Electrical substations – types, basic terms and classification, fiction relations between individual parts.
2. AC Switchgears – bay types and its equipment, operational manipulation, blocking of apparatus.
3. Installed power of transformer units in supply transformer station project, transformer parameters, project documentation.
4. Transformers operation – voltage drop, parallel operation, loses, overloading, transformer site.
5. Transformer protections – differential protection principle and performance, overloading protections, earth fault protection.
6. Substation automation system – hierarchy, individual level devices, bussbar protections.
7. Substation earthing system – basic terminology, design of earthing system, ground electrodes, earthing of distribution transformer stations MV/LV.
8. Substation earthing system – earthing theory, calculation of simple ground electrodes and earthig systems resistance.
9. Ripple control – purpose, principal and features, impact of power systems elements on ripple control signal transmission.
10. Power lines conductors and cables dimensioning – conductor ampacity, theory of conductor thermal characteristic.
11. Power lines conductors and cables dimensioning – theory of dynamic strength of conductor during the short circuit.
12. Overhead lines – mechanics of unsymmetrical hanging conductor, state equation and its solving possibilities, critical temperature and span.


The aim of course is to familiarize students with the current state of electrical equipment stations especially at medium and high voltage, with emphasis on operation and protection of transformers. Furthermore, to give information about the current substation automation systems. To give a comprehensive information about the theoretical foundations of designing of switchgears and conductors.

Specification of controlled education, way of implementation and compensation for absences

Labs are compulsory; correctly excused absence can be replaced by arrangement with the teacher.

Classification of course in study plans

  • Programme EEKR-ML Master's

    branch ML-EEN , 1. year of study, summer semester, 6 credits, compulsory

  • Programme EEKR-ML1 Master's

    branch ML1-EEN , 1. year of study, summer semester, 6 credits, compulsory

  • Programme EEKR-CZV lifelong learning

    branch ET-CZV , 1. year of study, summer semester, 6 credits, compulsory

Type of course unit



26 hours, optionally

Teacher / Lecturer

Fundamentals seminar

18 hours, compulsory

Teacher / Lecturer

Exercise in computer lab

9 hours, compulsory

Teacher / Lecturer

Laboratory exercise

12 hours, compulsory

Teacher / Lecturer