Power grid analysis

• Develop and implement power flow algorithm on a computer and interpret power flow results.
• Describe the basic principle of power system security analysis.
• Design and implement steady state contingency analysis.
• Understand balanced and unbalanced fault types.
• Calculate short-circuit currents of symmetrical faults in small grids.
• Understand symmetrical component transformation and determine sequence networks of loads, series impedances, transmission lines, rotating machines, and transformers.
• Apply symmetrical components and sequence networks in small grids and analyze unsymmetrical (single line-to-ground, line-to-line and double line-to-ground) faults.
• Calculate symmetrical or unsymmetrical fault currents in large grids using sequence bus impedance matrices.
• Describe the basic principles of distance relays, design their zones of protection in a distance protection scheme and determine the operating time for a given fault current from provided relay characteristics.

To meet the learning objectives, the learning activities are divided into the following three modules:

1. Grid analysis and security assessment.
This module contains lectures that cover an introduction to power flow analysis and how it can be implemented in a Python program, and an introduction to power system security assessment. The lectures provide the background theory and methods that students need to implement and apply in the first hand-in assignment, with the focus on load flow and contingency analysis.

2. Symmetrical and unsymmetrical fault analysis.
This module contains lectures that introduce fault analysis including symmetrical component transformation and its application to unsymmetrical fault analysis. The lectures provide the background theory and methods that students need to apply and implement in their second hand-in assignment. Part A of this assignment focusses on “hand calculations” for small grids; Part B extends the Python program developed in Module 1, to perform fault analysis for larger grids.

3. Result verification in PowerFactory
This module introduces Python as a tool to automate calculations and processes in commercially available software, using PowerFactory as an example. In the final project, students utilize the built-in functionalities available in PowerFactory to control system parameters and execute software functions through the Python interface. Within this project, students conduct load flow analysis, security assessment, and fault calculation in PowerFactory, and compare the results of the commercial software with those obtained from the Python program developed in previous modules. Students are expected to identify and explain potential differences between the outcomes produced by the two programs.

The students will use Python for solving the hand-in assignments and therefore an introduction to Python will be arranged for the students at the beginning of the course.

31730/46700

The course material categorized into three main modules where for each module, the learning activities are scheduled in two phases:

1. Classroom lectures to provide an overview of the theory and methods, supplemented with in-class exercises.

2. Hand-in assignments and project work where you work in groups.

The teacher will be present for relevant guidance, questions, and discussions.