Design and Optimization of a Linear-Rotary Electromagnetic Actuator Based on Analytical Model of Magnetic Flux

In this work, a design method for a linear-rotary electromagnetic actuator (LREA) presented recently in [1] is developed. The design method is based on an analytical model of magnetic flux. An assumption of optimal flux densities in the magnetic circuit of the actuator allows calculation of the required magnetomotive force and some related dimensions, however, most geometrical parameters must be chosen manually. The influence of each particular parameter of the actuator on the torque and inductance characteristics is analyzed to find advantageous parameter values. This analysis is performed for dimension ratios, which makes it universal for various sizes of the actuator. Further, we present the influence of some parameter combinations on the torque density. Finally, the analytical flux model is applied for stochastic optimization of the design. This procedure allows creation of much more efficient designs comparing to manual choosing of parameters and becomes feasible only with the analytical flux model proposed earlier, since calculation of three-dimensional magnetic field using finite element analysis (FEA) would require huge computational capabilities in this case.