Investigation of the active electromagnetic suspension system considering hybrid control strategy

Abstract
This paper deals with an electromagnetic damper, which is composed of a permanent-magnet direct current motor, a ball screw, and a nut, as an active actuator. The main objective pursued in the paper is to study the active electromagnetic suspension system (AEMSS) considering hybrid control strategy (the hybrid control strategy is a linear combination of skyhook and groundhook control strategy). For this purpose, the nonlinear equations of the electric circuit of the AEMSS should be developed. Supposing linear conditions, the coefficients determination of the hybrid control strategy is carried out in the frequency domain using the genetic algorithm in order to improve the vehicle performance and energy regeneration simultaneously. Afterwards, the achieved coefficients are used to examine the designed AEMSS in the actual conditions for an actual road profile. The simulation results demonstrate that the designed AEMSS has the desired performance while energy can be regenerated from the road excitation and transformed into electric energy. Furthermore, it has been shown that the designed AEMSS regenerates energy during the ascent and descent of a bump and consumes energy near the top of the bump.