Electromechanical Conversion of Energy
FSI-REEAcad. year: 2020/2021
The basic laws of electromagnetism applied in the theory of electrical machines. Magnetic circuits of electrical machines. The basic voltage equations, equivalent circuit diagrams, phasor diagrams, the basic electrical connections of electrical machines. Energy and power flow diagrams, losses and efficiency. Torque equation. Electrical machines performance. Nonsymmetrical loading. Influence of higher harmonics. Basic characteristics of electrical machines.
Learning outcomes of the course unit
The students will be acquainted with the basic knowledge of electromechanical energy conversion, with basic constructional parts of electrical machines and with the principle of electrical machines operation. Single-phase and multiphase transformers. Parallel operation. Three-phase induction motor. Generation of revolving magnetic field. Torque characteristic, starting of induction motors. Single-phase induction motor. Three-phase induction motor on single-phase mains. DC machine principle of operation. DC generators.Performance of DC motors .
Basic laws and terminology of electrical and mechanical engineering. Three-phase systems.
Recommended optional programme components
Recommended or required reading
Měřička,Haňka,Voženílek.::Elektrické stroje,ČVUT Praha
O'Kelly:Performance and Control of Electrical Machines,McGraw-Hill
Planned learning activities and teaching methods
The course is taught through lectures explaining the basic principles and theory of the discipline. Teaching is suplemented by practical laboratory work.
Assesment methods and criteria linked to learning outcomes
Control tests - 20 points
Individual projects - 15 points
Written and oral exam - 65 points
Language of instruction
To acquaint the students with the principle of operation and performance of transformers, induction machines, DC machines and synchronous machines. The theoretical knowledge is proved in laboratory exercises.
Specification of controlled education, way of implementation and compensation for absences
Attendance at practical training is obligatory.
Type of course unit
26 hours, optionally
Teacher / Lecturer
1. Basic laws of electromagnetism related to electrical machines.
2. Principle of electromechanical energy conversion.
3. Transformers. Ideal transformer, actual transformer, basic equations.
4. Principle of operation and construction of power transformers.
5. Three-phase transformers, winding connection, parallel operation.
6. Magnetic circuit and winding of electrical machines.Principle of operation of induction machine, generation of revolving magnetic field.
7. Equivalent circuit diagram, fundamental equations and torque characteristics.
8. Starting of induction machines speed control.
9. Single-phase induction machine. Three-phase induction machine in single-phase mains. The higher harmonics influence.
10. Synchronous machine. Principle of operation and construction.
11. Theory of nosalient machine. Torque characteristic, synchronous machine with individual load and parallel operation.
12. DC machines. Principle of operation and construction, fundamental equations.
13. DC machines steady -state performance.
26 hours, compulsory
Teacher / Lecturer
1. Work safety and the main parts of rotary electrical machines. Assembly and disassembly of electrical machines.
2. Principle of torque measurement, dynamometer.
3. No load a short circuit transformer test.
4. Winding connection. Load test a efficiency, measurement of a transformer.
5. Three-phase induction motor. Winding connection. No load and blocked rotor test. Induction motor parametr determination.
6. Measurement of induction motor torque characteristics.
7. Induction motor starting.
8. Synchronous machine parallel operating with mains.
9. Measurement of torque characteristics.
10. Parametr determination of synchronous machine with salient poles and with nosalient rotor.
11. DC machine. No load test. Selfexcitation of shunt generator.
12. Connection of DC motor to mains. Speed control characteristics of DC motors.