MTT035 High voltage engineering lp3 HT24 (7.5 hp)

Course is offered by the department of Electrical Engineering

Contact details

Examiner, lecturer: Xiangdong Xu, xiangdong.xu@chalmers.se

Examiner, lecturer: Jörgen Blennow, jorgen.blennow@chalmers.se

Tutor, lecturer: Thomas Hammarström, thomas.hammarstrom@chalmers.se

Teacher: Becky Bergman, becky.bergman@chalmers.se 

Lab tutors: Vaishnavi Ravi, raviv@chalmers.se, Jin Wang, jinw@student.chalmers.se and Daniel Svensson, daniesve@chalmers.se

HV-lab/safety manager: Thomas Hammarström, thomas.hammarstrom@chalmers.se

In the course the following student representatives have been appointed:

TBD.

Course purpose

This course serves as the initial step for students into high voltage engineering, focusing on three key areas:

1.     Basics of Experimental High Voltage Engineering: Students will learn fundamental concepts and gain an essential understanding of classical experimental techniques in high voltage engineering.

2.     Understanding Electric Power System Components: The course offers an overview of the components of electric power systems, equipping students with knowledge critical for further studies and professional work in this area.

3.     Preparation for Advanced High Voltage Technology: Acting as a precursor to the more in-depth "High Voltage Technology" course, this program is designed to set the stage for comprehensive learning in the field.

Completion of this course and its advanced follow-up prepares students for careers in electric power industries, such as R&D engineering in high voltage design and lab activities or as engineers managing power system components. These courses also lay a strong foundation for postgraduate studies in electric power engineering, providing a significant stepping stone for academic and professional growth in this specialized area.

Schedule

TimeEdit

Course literature

• Andreas Küchler, High Voltage Engineering, Fundamentals - Technology - Applications. ISBN 978-3-642-11992-7 or ISBN 978-3-642-11993-4 (e-book), Available at Store but also as e-book through Chalmers library.

• R. Hileman: Insulation Coordination for Power Systems, 1999, CRC Press, ISBN 0-8247-9957-7 (available as e-book through Chalmers library).
• High Voltage Engineering, Tutorial exercises (uploaded on Canvas).
• Additional course material uploaded on Canvas.

Textbooks that can be used for reference

• Kuffel, W. S. Zaengl, J. Kuffel: High Voltage Engineering: Fundamentals, 2^nd ed. 2000, Newnes, ISBN 0 7506 3634 3. Available as e-book through Chalmers library.

Course design

This course begins with basic electric field calculations in simple geometries, moving to gas discharge physics, Townsend’s theory of electric breakdown, and Paschen's law. A key focus is experimental techniques, complemented by practical lab sessions. The course revolves around the theme of insulation coordination, linking various topics together. Additionally, it covers power system components and their characteristics, both theoretically and through a substation visit.

Key Topics Covered in Lectures and Tutorials:

• Electric Fields Fundamentals: Boundary conditions, Gauss' law, field distribution calculations in different geometries, and field control under ac-stress.
• Gas Breakdown Under Low Pressure: Gas kinetics, Townsend's breakdown mechanism, Paschen's law, voltage-time characteristics, and the influence of environmental conditions.
• Overvoltages: Lightning mechanisms, Rolling Sphere theory, power line protection, wave impedances, travelling waves, atmospheric and switching overvoltages.
• High Voltage Laboratory Techniques: Techniques for generating and measuring high voltages, including transformer and rectifier circuits, impulse generators, and voltage and current measurement methods.
• Insulation Coordination: Overvoltage reduction, surge arresters, test methods, and insulation coordination approaches.
• Power System Components: In-depth study of various components like overhead lines, cables, transformers, and substation equipment.
• Power System Ageing: Strategies for assessment, maintenance, and retirement.
• International Work Environment: compulsory lecture and workshop on working in international settings, focusing on collaborative strategies.

Laboratory Experiments:

Two compulsory experiments are included:

1. “Lightning impulse testing” – Exploring the impulse generator, high voltage measurement techniques, and the evaluation of impulse tests.
2. “Overvoltages in cables” – Studying wave impedances, surge arrester effects, and measurements of impulse voltages and currents.

Students are required to submit brief reports for each experiment, discussing and summarizing the laboratory topics. Detailed instructions will be provided by lab tutors and in the lab-pm.

Changes made since the last occasion

The result of the course evaluation previous year is accessible from this link:

https://course-eval.portal.chalmers.se/SR/Report/Token/18171/0/869d692c-6447-4bb8-9c4b-048e49f9b9e4

Most things worked fine and should be kept. Suggested changes:
Keep the same lab groups for both labs, at least as long as there is distance learning. – Pros and cons will be discussed during the course introduction

Use only one main textbook in the course (and use the other book as reference literature) – References to the textbook by Kuffel/Zaengl is removed

The teacher should supply students with measurement data to a larger extent during the lab. – We will try!

Learning outcome

• Electric Field Analysis: Conduct analytical calculations of electric field distributions in various insulation systems, including plane-parallel, coaxial, and spherical geometries.
• Geometry Assessment for Insulation: Identify geometries in insulation systems that lead to high electric fields and propose design improvements.
• Understanding of Electric Breakdown in Gases: Explain the Townsend’s breakdown mechanism in gases at low pressures using a ballistic collision model.
• Engineering Perspective on Electric Withstand Strength: Describe factors crucial for achieving high electric withstand strength in engineering terms.
• Utilizing Paschen Curve: Apply the Paschen curve to estimate electric strengths in short homogenous gas gaps under varying pressures and ambient conditions.
• Impact of Time Lags on Breakdown Voltage: Discuss how time lags affect breakdown voltage and their implications on insulation coordination.
• High Voltage Laboratory Equipment Proficiency: Select appropriate laboratory equipment for high voltage generation and measurement for specific tests.
• High Voltage Test Setup and Safety: Plan and execute a high voltage test setup safely, assessing risks to personal safety and equipment integrity.
• High Voltage Test Procedures Application: Perform tests to determine breakdown and withstand voltages, using appropriate high voltage test procedures.
• Statistical Evaluation and Atmospheric Corrections: Analyze test results statistically and apply necessary atmospheric corrections.
• Power Components Identification: Recognize electric power components in substations, understanding their roles and characteristics.
• Equipment Design Evaluation: Compare different equipment designs, discussing their advantages and disadvantages.
• Construction Elements of Power Lines: Identify and explain the different elements in overhead and cable lines' construction.
• Fault Calculation for Overhead Lines: Calculate the probable number of annual faults in overhead lines using the Rolling Sphere theory and assess back-flashover risks.
• Overvoltage Analysis in Power Systems: Calculate overvoltages due to travelling waves and reflections, and demonstrate surge arresters' role in limiting these stresses.
• Switching and Temporary Overvoltages Origins: Explain and illustrate various origins of switching and temporary overvoltages.
• Insulation Level Coordination: Under expert guidance, coordinate the insulation level of apparatus concerning overvoltages, considering protective measures for technical and economical risk balancing.
• Understanding Power System Ageing: Gain basic knowledge in power system ageing, including assessment, maintenance, and retirement strategies.
• Environmental and Health Impact Assessment: Discuss the potential negative impacts of various technologies on the environment and human health, considering factors like insulation media and electromagnetic field exposure.
• International Working Environment Reflection: Reflect on the opportunities and challenges presented by working in an international environment.

Examination

Voluntary Trial Exam:

Date and Time: Friday, January 26, from 10:00 to 10:45.

Location: Room HC3.

Purpose: Earn up to 5 bonus points for the final exam (valid for one academic year).

Requirements for Final Grade:

• Pass the final written exam.
• Complete and pass all laboratory exercises, including short reports.
• A compulsory lecture (19 Jan. 2024) on work in an international environment.
• A compulsory workshop (27 Feb. 2024) on strategies for work in an international working environment, with focus on group work.
• Submit an individual reflection on group diversity by March 6, 2024.

Final Written Exams Dates, Location and Times:

• March 13, 2024, at Johanneberg from 14:00 to 18:00.
• June 07, 2024, at Johanneberg from 14:00 to 18:00.
• August 21, 2024, at Johanneberg from 14:00 to 18:00.

An exam with illegible handwriting will be marked as failed. Assumptions, quantities and symbols introduced must be motivated and defined. Always focus your answer on the question asked and do not try to write as much as possible about related subjects. Put the papers well-ordered, with the paper header correctly filled in, in the exam enclosure. English is the only accepted language.

The total number of points of the written examination will be 50 of which about 50% are of a descriptive nature and about 50% are of a calculative nature.

Exam allowed aids: Physics Handbook, Beta Mathematics Handbook, Chalmers approved calculator and printed language dictionaries (i.e. books, not electronic ones). All the aids must be note-free.

Grades: 5: 40p (80%); 4: 30p (60%); 3: 20p (40%); Failed < 20p (<40%) according to the Chalmers’ grading system.

For obtaining the final grade in the course the two compulsory laboratory experiments (about four hours each) must be approved . In order to enhance understanding, short reports must be submitted in conjunction to each laboratory experiment, discussing and concluding the topics of the laboratory. Further instructions are given by the lab-assistants and in the lab-pm.