Advances in the design of TORUS machines

This paper combines the experiences gained at UMIST, University of Durham and University of Rome "La Sapienza" from the research activities carried out in the last decade through design and construction of several prototypes of TORUS machine. Opportunity for collaborative research was given by an European Community funded project which led to construction and testing of two machine prototypes intended for a direct-drive wind generator application. Both machine prototypes were developed under a common design specification of 5 kW, 200 rev/min but, actually, different design criteria were adopted for the selection of the electromagnetic and mechanical arrangement of each generator machine. In the paper, design characteristics and experimental results taken from the two small-size direct-drive wind generators are compared and practical issues on design and construction of TORUS machines are discussed.