An examination of the scaling properties of electric micromotors and their magnetic duals

Advances in silicon micromachining technology are such that small electric motors fabricated using integrated circuit technology may be able to compete with conventional magnetic motors in the future. While it is apparent that at extremely small scales electric actuation is favourable, it is not clear at what point this transition takes place. An examination of this question for one particular motor design is presented. The output coefficient of a twelve stator pole, eight rotor pole variable capacitance synchronous motor is determined and the dimensions of an equivalent magnetic machine are estimated. The influence of permanent magnets in the rotor structure of the magnetic machine is also considered