Meet a PhD graduate: When lightning strikes

  • Søren Find Madsen
  • Managing Director of Highvoltage.dk and Technical Manager of Testinglab Denmark
  • M.Sc. and PhD from DTU Electrical Engineering
  • Spare-time recreation: wife and two children. Tries to run when possible but being in charge of two businesses takes up a significant amount of time
  • Age: 33

”I handed in my PhD project in 2006 and received my diploma in the beginning of 2007. I finished my master’s studies back in 2001 and thus worked for a couple of years as a consultant with a firm of consulting engineers. However I found that the percentage of academically challenging assignments compared to the routine work was too low seen in the light of my wishes, so when my previous supervisor Joachim Holbøll called and asked me if I was interested in starting a PhD project at the department, I did not take long to decide”.

The approach from DTU Electrical Engineering led to several years of working with protection of wind turbines against lightning. This engagement has since continued and has inspired Søren Find Madsen to establish his current businesses Highvoltage.dk and Testinglab Denmark, the latter in collaboration with Kim Bertelsen.

What were the main topics of your PhD project?

During my studies I tried to achieve an increased understanding of the extremely complex problems that exist in connection with protecting wind turbine blades from lightning. Back when wind turbines were still of modest dimensions, these problems were not an issue and the blades could be protected using ordinary methods. Today the tips of the blades of modern wind turbines operate up to 150-200m over the surface and this has increased the challenges manifold. It is not only a question of whether a turbine is struck by lightning, because this is inevitable; it is more a question of how many times it is struck and with what consequences in respect of the lifespan and functionality of the wind turbine. Furthermore, existing and future wind turbines will also contain increasing amounts of high-tech equipment which must also be protected against the effect of lightning and as a result, a large part of the research focuses not only on the ’protection of the wind turbine against lightning’ but rather on ’protecting integrated electronics against lightning’. This led to a six months research stay during my PhD studies with Lightning Technologies Inc. in Massachusetts, USA. The company is one of the worlds’ leading testing laboratories in the field of protection of aircrafts against lightning. A large part of the problematic is in fact completely parallel and telecommunication and cell phone masts and a large number of other tall constructions contain sensitive equipment and these constructions are of course struck by lightning.

What do you remember as positive aspects of your study period?

I started my master’s programme as an 'Energise' with subjects the fields of electrical, machine and construction engineering, but ended up taking all subject in the last part of the studies at DTU Electrical Engineering. The basic understanding of the science of energy is still very important but during my studies I fell for the inspiring study environment which characterizes DTU Electro. It is my impression that the department truly gives special treatment to its students, and I certainly remember the fine reception I received. So even though it started out being the social element at DTU Electrical Engineering which appealed to me, I was quickly attracted to the scientific work as well.

And what was your impression of your following PhD studies?

In addition to having the opportunity to really go into depth and be allowed to spend a long time on one specific topic, the most positive aspect was probably the fantastic opportunities to establish contacts and create a network with other researchers and industrial partners. The results from my PhD work are disseminated through project participation and exchange of experience among manufacturers and users of wind power installations and have been incorporated into the most recent lightning protection standard for wind turbines, IEC 61400-24.

Have you found your experiences from your studies to be useful in your current work?

Yes very much so; both the establishment of my own consultancy business in 2005 and the extension in 2008 with the formation of the business Testinglab Denmark which performs mobile high-voltage tests for electronic components and installations are direct results of my PhD studies. Our test facility enables wind turbine manufacturers, wing manufacturers and sub-contractors to test the resistance of components and systems towards lightning.