New, Varying-Capacitance, Electrical Machine. Phase 2

摘要

The varying-capacitance accomplishes energy conversion through the electro-mechanical coupling which is inherent when the capacitance between rotor and stator varies periodically as the rotor turns. The concept developed in the work achieves a very high energy density in the rotor-stator gap through a combination of solid insulation, with a thin layer of vacuum. This leads to a high power density for the machine as a whole. Following an initial (Phase I) experimental demonstration of feasibility, a 10 kilowatt machine, of the disc type, was designed, built, and tested. An important accomplishment was the development of a method for vacuum-casting rotor discs of insulating polymers. The machine was operated at total voltages up to 40 kV and speeds up to 6000 rpm. For application at voltages of 10 kV or more, and at frequencies of 400 Hz and higher, and for HVDC applications, the machine is much lighter, and somewhat smaller than conventional magnetic machines of the same power.