THESIS - Harmonics' effects on electrical equipment in hydropower plants

Background 

In a normal electrical power system, an electrical power grid, the a.c. voltage varies with a sinusoidal shape, with a specific frequency; in the Nordics it is 50 Hz. When a linear electrical load is connected to the electrical grid, it will draw a sinusoidal current with the same shape and frequency as that voltage without any harmonics. 

When non-linear loads are connected, such as rectifiers, thyristors, fluorescent tubes, motor controls, etc., they will draw a current that is not sinusoidal, giving harmonics in the system. These harmonics may be more or less harmful as they in various ways will create extra heat and energy losses etc. Harmonics in the electrical grid is also a common reason to problems with electrical quality. 

For hydropower utilities this can cause problems. Fortum has a case where it is suspected that harmonics have caused short circuit in vital electrical installations in a hydropower plant. In this case the source of the harmonics is suspected to be a windfarm. It is known that grid operators have similar problems. 

Objective 

The Master Thesis project is expected to perform a case study on how harmonics are created in the system and how they can cause problems for electrical equipment in hydropower plants and switchyards or other equipment. The study should also explain in general the overall problem with harmonics in the power system, how common the problem might be and if there is a need of and possible means of prevention. Collaboration with a grid operator may be included. A study should be done for the case in one of our hydropower plants.  

Our offer 

At Fortum we see a Thesis Project as a good way to get to know you during your study time and for you to learn more about Fortum and how our business is working. A Supervisor will be appointed to support and guide you through the Thesis Project and you will also be part of the network of people within the Company and with other Students doing their Thesis by us.  

For a well performed and approved work, we will pay a taxable lumpsum award. 

This Thesis Project is preferably executed at any of our offices in Sweden; Stockholm/Solna, Västerås, Borlänge, Karlstad, Östersund or Arbrå. 

Site visit and field measurements are expected to be included. 

Your Qualifications 

The Master Thesis project is preferably conducted by one or two students, studying at Master programs related to Power Systems, Electrical or Energy Technology. The Project may be executed in Swedish or English.  

We expect you to have a theoretical insight in Energy Economics and interest in the development of the power system.   

Interested? 

To apply, register your CV and a personal letter of maximum one page or a Power Point presentation of maximum two slides, in our Recruitment Tool via “Apply now”, latest by 24th November 2024. Applications will be evaluated continuously and an applicant may be on-boarded before this date.

The personal letter shall include an approach on how you would like to investigate the idea. Mark your application with the reference number HYG-158.

If you have General questions about Theses or Internship at Fortum, please address those to fortumcareers@fortum.com. 

Please note that we have more Master Thesis Projects open for application at our recruitment site.