Courses

Circuit Analysis

General

Course Contents

1. Basic concepts and principles of Electrical Engineering, electric field, magnetic field, concentrated and distributed circuits, wavelength, radiation, field propagation velocity. Elements of circuit topology (branch, loop, node, potential, voltage, current, coupled reference directions, power flow, Kirchhoff’s laws.
2. Tellegen’s theorem, separation groups. Two-terminal elements, linear and nonlinear elements, voltage sources, current sources, dependent and independent sources. Resistor, capacitor, inductor, open circuit, short circuit, switch.
3. Passive and active elements. Transformer. Two-terminal circuits, port, poles, equivalence of circuits, in-line and parallel connections of R, L, C, source connectors. Simple model of real voltage and current source, equivalence of voltage and current sources, Norton and Thevenin equivalent circuits, [Millman theorem].
4. Introduction to signal theory, types of signals, Fourier analysis, mean and root mean square value, step function, Dirac function, sampling theorem.
5. Circuits in the field of frequency, rotating vectors, operations with rotating vectors, transformation of R, L, C in frequency, circuit function, equivalent circuits, voltage and current divider, scalar circuits, RLC and GLC resonance. Resonance.
6. Generalised circuit analysis methods. Simple loop method in the field of frequency. Impedance matrix, Cramer method. Node method in frequency. Complex conductivity matrix. Examples. Input and transfer conductivity. Input and transfer impedance.
7. Output impedance and conductivity, voltage and current transfer functions. Connecting circuits in cascade.
8. AC Power. Active, reactive, complex and apparent power. Units of measurement. Power as a sinusoidal function. Frequency of electrical power. Power triangle. Reactive power compensation. Compensation as a special case of resonating. Parallel compensation vs. series compensation.
9. Maximum power transfer theorem. The case of the given consumer as opposed to the given amplifier. Matching. Why power lines are not adjusted.
10. Three-phase circuits. Polar voltage, phase voltage, line currents, phase currents. Y-Y, Y-Δ, Δ-Y, Δ-Δ connections. Relationship between polar and phase magnitudes. Neutral current in a symmetric three-phase system. Grounded and non-grounded neutral. Neutral brake. Phase brake. Two-phase break.
11. Power in three-phase systems. Power measurement with Aron connection.
12. Transient phenomena in electrical circuits. Resistor, capacitor and inductor models in time. Differential equations. Unguided first-order circuits. Natural response. Stability. Time constant. Recovery time. Linearity. Examples.
13. First Order circuits driven by DC or AC source. Zero Input Response. Zero State Response. Stability. Initial and final state method. Impulse response, step response.

Educational Goals

Upon successful attendance of the course the student should be able to:
• classify a circuit as concentrated or distributed
• possess fundamental concepts of signal theory
• recognize and possess the properties of the basic two terminal elements in time and in frequency
• understand the operation of simple electrical circuits and the basic concepts governing them, such as load, potential, current, voltage, resistance
• understand fundamental circuit theorems and general circuit analysis methods in time and frequency
• understand and estimate AC one- and three-phase electrical power circuits,
• perform simple calculations on simple first-order transition circuits in time

General Skills

Research, analysis and synthesis of data and information, using corresponding technologies, decision making, team work, implementing criticism and self-criticism, promotion of free, creative and inductive thinking.

Teaching Methods

Lectures, Exercises, Online guidance, Projected Presentations, E-mail communication, Online Synchronous and Asynchronous Teaching Platform (moodle).

Students Evaluation

Assessment Language: English / Greek
The final grade of the course is formed by the grade of the written final examination which includes:
Solving problems of application of the acquired knowledge, Short answer questions etc

Recommended Bibliography

Nikos I. Margaris, Electric Circuit Analysis. Tziola Publishing, 2010. (in Greek)
Nilsson Riedel, Electric Circuits, 9th edition, Prentice Hall, 2011. (in English and Greek)
Alexander C., Sadiku M., Fundamentals of Electric Circuits, 6th edition, McGraw Hill, 2019. (in English and Greek)