The vast majority of wind turbine electrical generators are three phase, radial flux machines, of either alternating current induction (such as the Double Fed Induction Generator) or permanent magnet synchronous varieties.
Whilst these types and topologies of machine are commercially viable for wind, as demonstrated by the growth in the industry, their novelty is deficient. Wind turbine generators have primarily been selected from an existing range to fit the application rather than being designed to suit the application.
This PhD project will explore atypical or, for lack of a better word, 'unusual' machine topologies. Homopolar and heteropolar variants of axial and transverse flux machines, both AC and DC, will be explored. These types have been shown to reduce generator active mass to achieve competitive power densities. Generator types and topologies which may have been overlooked or disregarded in past research, possibly when the wind turbine industry was in its infancy, will be revisited and evaluated in a modern wind turbine generator application.
The electrical generator design space will be explored for wind turbine applications by comparing these unconventional machine topologies with the common alternatives in terms of power density and quality, volume, cost, manufacturability and energy conversion efficiency. Consideration of materials will also be an important aspect of this research as there is a desire to reduce or remove the use of rare earth permanent magnets due to the required volume, cost, and geo-political and environmental issues.
In essence, the application of electrical machines in wind turbine generators will be revisited from the perspective of 'starting from scratch' in order to select the most appropriate generator technology without bias from current commercial choices.
In addition to computational studies and analyses, this research may also require experimental studies of physical prototypes.
The research has potential benefits for future large-scale wind turbine manufacturers as well as for small-scale wind and other offshore renewables applications as a result of the 'bottom-up' approach to electrical machine design for particular applications.