Measurements in Stor-Rotliden’s wind farm where transformer failures occurred
are planned in the project. In comparison with the previous work in this field, the
focus here is on the design of grounding systems (GS), especially their HF
characteristics.
Component models derived in a previous Vindforsk project are improved and the
results are generalized so that they can be applied to components of different sizes.
Analysis of different GS is performed and the importance of different factors that
influence generation and propagation of transient overvoltages is determined.
Later it is analyzed how the transients influence connected components, and what
protection is needed.
