Design and control of an electromagnetic actuator without mechanical springs

The paper describes a new form of actuator that depends on eddy currents fo r its operation. Its design with the aid of computational electromagnetics taking account of the external power supply and thermal effects is presente d. The variation of the thrust with displacement of the actuator is shown t o depend largely on one design parameter. It is shown however that this res triction can be overcome by modulating the exciting voltage as a function o f the actuator displacement in real time. The control is achieved by the us e of DSP hardware and software. The need for a mechanical spring is elimina ted by the design employing a single conducting tube with two stators.