Contactless rotating energy transformers can be used whenever the energy transfer to a rotating system by means of slip rings causes technical or economic problems. One application example is the transfer of energy to the rotor of an electrically excited synchronous machine. Usually contactless rotating energy transformers are built up by means of so-called pot cores and therefore quickly reach a limit with the variance of the installation space and the maximum transmittable power.
At the Institute of Electrical Energy Conversion, a completely new concept of a rotating inductive energy transmission line was designed taking into account costs, speed stability, efficiency and weight. Compared to other known contactless transformers, the use of expensive and heavy ferrite materials could be significantly reduced without significantly increasing the losses. The principle of the transformer is based on an incompletely pronounced flow of individual ferrite plates and a winding arrangement with a defined magnetic flux curve. The combination of this not pronounced flow guidance by means of individual ferrite plates and the winding arrangement ensures a relatively high coupling factor and relatively low eddy current losses in the aluminium with a massive reduction in material input.
The rotating inductive energy transmission path can be scaled and adapted for applications with almost any speed, diameter and power. Due to the construction with single ferrite plates, constructions with a very large free internal passage can be realized. Possible applications are the replacement of maintenance-intensive and expensive slip ring systems, for example in electrically excited synchronous machines.