I am in the High Voltage and Insulation Diagnostics Research Group, within the department of Electromagnetic Engineering in the `school' of Electrical Engineering at the Royal Institute of Technology KTH in Stockholm.
The group conducts teaching and research in the subject of high voltage and electrical insulation.
The teaching is mainly at the higher undergraduate levels in the final year, or within MSc courses on Electric Power Engineering.
The group's research has a strong tradition in diagnostic methods, whereby non-destructive measurements are used to assess the condition (and implicitly the fitness for service) of the insulation in high-voltage apparatus such as cables, transformers and generators. There is also ongoing work on the electrical properties of new insulation materials.
A lot of work was done in the 1990s on the use of low-frequency high-voltage dielectric spectroscopy for detection of water-treeing in cables. This was continued with time-domain reflectometry for location of water-treed regions by their effect on wave propagation, and extension of this technique for use while the cable is energised. The last in this chain of projects finished in 2009.
Another main thread of the group has been partial discharge (PD) measurements. The use of varied (down to very low) frequencies of applied voltage has been investigated for the extra information it can give about the nature of PD sources. For example, the much more worrying delamination in stator insulation can be expected to exhibit different low-frequency behaviour from that of the less worrying largely spherical void. Work on measuring PD at low frequencies ended around 2001, and a project on measurements and simulation of PDs in cavities within canonical cavities in solid insulation finished in 2008. A further project on PD with non-sinusoidal excitation was started in 2009.
My project finished, as far as the PhD funding and studies were concerned, in 2010, but continues part-time during other duties. It considered both DS and variable-frequency PD measurements, applied to stator insulation, a type of object not given so much attention as cables and transformers in the earlier work at within the group.
For more information about what is and has been going on, please see the annual reports (which over the years have consisted of varying mixtures of research groups and departments, and varied levels of detail). Another possible source of enlightenment is the publications, which unfortunately aren't sortable below the level of the whole department.
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Page started: 2003-10-01
Last change: 2010-09-27