Luleå University of Technology researcher visiting Professor in Universidad de Córdoba

Researchers in Electric Power Engineering visiting Córdoba. From left: Dr. Sarah Rönnberg, Luleå University of Technology, Dr. Aurora Gil-de-Castro, University of Córdoba, and Professor Math Bollen, Luleå University of Technology.

A year ago, Sarah Rönnberg got her PhD in Electric Power Engineering. Shortly thereafter, she became a visiting professor at the University of Córdoba, Spain, where she along with Dr. Aurora Gil-de-Castro will be researching how the transition to LED lights affect the power grid.

 It is a successful collaboration between Electric Power Engineering at Luleå University of Technology and the University of Córdoba that led to Sarah Rönnberg’s opportunity to become guest professor. As a PhD-student Sarah spent a long time in Córdoba and she has published several scientific articles together with researchers there.

– In Córdoba, I will mainly be working with a pilot study on possibilities to measure the so-called flicker of modern energy-efficient lighting. The goal is to be able to identify which parameters for power quality that can cause flicker, to for example LED lights, says Sarah Rönnberg, PhD in Electric Power Engineering at Luleå University of Technology.

Dr. Sarah Rönnberg at her office on campus in Skellefteå.

The research project in Córdoba fit well into Sarah’s research on conducted signals on the power grid, so called harmonics and supraharmonics, and how these signals interact with appliances and lighting we connect in our homes.

– I want to find answers to what consequences, for example the transition to LED lighting, will have for both the power grid and to the appliances we connect. We know for example that the voltage fluctuations at a certain frequency causes visible flicker on a light bulb, but we do not know if the same applies to LED lights.

Sarah Rönnberg also want to build on the knowledge she and the research group have in the area of supraharmonics.

– The Swedish Energy Agency and the electric power industry is funding my research through the Elektra program that is administered by Energiforsk. I have received funding for two years in order to develop methods and models that help us understand and quantify the signals in the power grid. Supraharmonics is also something that is often mentioned in working groups and standards bodies as one of the major challenges we have to solve in the electric power field.