COMPUTATION OF FLUX AND FORCE IN AN SMCO5 DC LINEAR MOTOR WITH U-SPRING SUPPORTS

Linear dc motors, with very limited travel length and using U-spring s upports may be used in clean rooms where frictionless movements do not produce any dust. Tests have been carried out after designing and con structing such a motor. In addition, two finite element software packa ges: 2-dimensional PE2D and 3-dimensional MEGA have been used to compa re the flux density distribution in various parts of the motor and als o the static thrust at various excitations. The results can be used to obtain an optimum design of the motor. The thrust coefficient compute d using the PE2D package, differs from the result of the MEGA package by 0.56% and from the test result by 2.9%. Using the PE2D package, the force affecting the coil has also been calculated. To this end, four methods were used and the results compared. Except for the Maxwell str ess method, two calculations of the Lorentz force and calculation of f orce from the definition have given results that differ by less than 2 %.