# Power systems I

This course covers the fundamentals of power system modeling, structure, and basic characteristics. It helps the students to understand the functional characteristics and to develop models for component-level as well as system-level analysis. The basic power system components, such as synchronous machines, transmission lines, transformers, and loads, are analyzed and their impact on the system is considered through real-life scenarios. The course focuses on steady-state, symmetrical, and normal (no-fault) operation.

Petros Aristidou

## Learning outcome

On completion of this course, students should be able to:

• Explain the basic operation of electric power systems for generation, transmission and distribution, and consumption;
• Explain the basic principles and the functionality of the basic components in a power system (buses, transmission lines, transformers, AC electric machines);
• Be able to analyze the power flow numerically in small systems using common power system models and methodologies;
• Appreciate, through basic case studies, the technical challenges in both the design and the operation of power systems.

## Prerequisites

The following course knowledge is prerequisites for this course:

1. Engineering mathematics (advanced mathematics I-III, linear algebra)
2. Physics I-III
3. Electric circuit analysis I&II
4. Control systems

## Syllabus

The course consists of these parts:

1. Introduction to electric power systems (basic functionality, generation-transmission-distribution structure, load consumption)
2. Single-phase and three-phase AC circuits (complex power, power factor, reactive power compensation, Y-$\Delta$ transformation)
3. The per-phase and per-unit system representation (one-line diagram, benefits of pu, base value selection, single- and three-phase pu, base system conversion)
4. The power transformer (Ampere and Faraday laws, basic principles, ideal and real transformer model, single- and three-phase transformer models, three-phase transformer configuration)
5. Introduction to rotating machines (fundamentals of electromechanical conversion)
6. Synchronous machine (fundamentals, EMF, power/torque, equivalent circuit, generator/motor operation)
7. Induction machine (fundamentals, power/torque, slip, generator/motor operation)
8. The transmission line characteristics (design and parameter derivation, $\Pi$-model, line approximations)

## Coursebooks

• Chapman, S.J., “Electric machinery fundamentals”, 4th edition McGraw-Hill, 2005
• D. Glover, M. S. Sarma and T. Overbye, “Power System Analysis & Design”, 6th edition, Cengage Learning, 2017
• Κ. Βουρνάς, Γ. Κονταξής, “Εισαγωγή στα συστήματα ηλεκτρικής ενέργειας”, εκδόσεις ΣΥΜΜΕΤΡΙΑ, 2010

## Delivery

Due to special circumstances, this year the lectures are taking place online. This might be modified according to the requirements and the regulations.

• Theory delivered through lectures (in class ≈ 30 hours)
• Practical examples (online ≈ 12 hours)
• Hardware laboratory work (in lab ≈ 8 hours)
1. Three-phase circuits
2. Single-phase power transformer
3. Three-phase power transformer
4. Power-factor correction