OPTIMIZED DESIGN AND 3-DIMENSIONAL (3-D) FINITE-ELEMENT ANALYSIS OF AROTARY ACTUATOR

Automotive vacuum actuation systems are being replaced by electromecha nical actuators. Extremes of temperature and fluctuating voltage suppl y complicate the use of electrical apparatus in such applications, Min imal cost and continuous duty operation constraints drive the optimiza tion process. The design and analysis of a variable reluctance rotary actuator is presented for 12-V automotive applications, A simple linea r model is used for optimization of the magnetic coil dimensions. Frin ge effects and nonlinear magnetics are modeled with a three-dimensiona l (3-D) finite element model. Output torque computed with the model is compared to prototype device test results, The effects on different s teel grades are examined.