Vernier hybrid wind turbine generators

Abstract

A great deal of research is currently being undertaken in the field of renewable energy, much of it dedicated to wind power conversion and focussing on a machine topology that increases efficiency. The vernier hybrid machine, VHM, is one topology considered and has promising features for use in direct drive and variable speed operation. Using the VHM topology, two prototype generators were built and tested. The machines use magnets that are buried within the stator and orientated in a flux concentration arrangement. The flux paths in the machines are inherently 3D in nature and thus require complicated modelling methods to achieve sufficient design accuracy. Various tests were conducted in an effort to find results that will describe the machines characteristics and operating mechanisms. It was found that increased torque handling capabilities can be observed at the detriment of power factor and construction complexity. With the use of power factor correction and suitable construction techniques the VHM is a viable wind turbine generation technique. To determine whether it is suitable for renewable energy applications would require an in depth economic feasibility study over the operating lifetime of the machine.