Nonlinear modeling and analysis of electromechanical actuator.

For more electric aircraft (MEA), in order to reduce air craft operating maintenance costs, electro-mechanical actuators technology is a good substitution for flight controls actuation. This paper develops a nonlinear dynamic model for EMA with roller-screw inside widely used in flight control actuation, as well as the linear model. This dynamic model incorporating nonlinear friction functions from the electric motor and roller-screw. It has a significant influence on the actuators' performance. In this research, the nonlinear model of the EMA is derived, and the nonlinear dynamic model is used to depict the electric motor friction while the efficiency ratio for the roller-screw. Then the time domain analysis is completed based on the open linear system under the Matlab environment. LuGre friction model is added to simulate the nonlinear dynamic friction torque. The friction losses influence analysis has been also been studied, simulation result displays that the friction torque generates the flat top and dead zone phenomenon, especially in the low frequency response.