Patent ID: 6326713
Filing Date: 2001-12-04
Classification: H02K

Abstract:
An a.c. electrical machine comprising at least a first and a second transformer, each transformer including at least one primary coil mounted upon a first mounting and at least one secondary coil mounted upon a second mounting, said transformers being arranged to be inductively coupled each to at least one other and further arranged such that magnetic fields are produced solely or substantially solely by current flowing through said primary coils and said secondary coils, said secondary coils being interconnected and arranged such that said machine has a balanced state in which the voltages, currents, fluxes of said primary coils are such that substantially no current flows in the secondary coils and an un-balanced state in which said voltages, currents and fluxes of said primary coils are such that current flows in said secondary coils, and further arranged such that said primary coil mounting and said secondary coil mounting are moveably mounted relative to each other, the machine further comprising an unbalancer arranged to adjust said voltages, currents, fluxes, of at least one of said primary coils of said first transformer relative to said primary coils of said second transformer to introduce an electromagnetic unbalance between said transformers such that said machine enters said un-balanced state, thereby transferring electrical power between said primary and secondary coils, and transferring mechanical power between said first and second mountings.