Implementation of a Field-Oriented Control Strategy for Electromagnetic Shock Absorbers

Chassis electrification is paramount in the automotive transition towards emission reduction and automated driving. In this context, electromagnetic shock absorbers are regarded as a promising technology for chassis control. They enhance the suspension with active and passive forces by means of a suitably interfaced and controlled electric machine. To this end, Field-Oriented Control is commonly adopted for brushless permanent-magnet machines. However, the suspension experiences impulsive forces at high speed, when the vehicle undergoes through bumps or potholes. Thus, a field-weakening strategy must be included to guarantee stable and efficient operation in the aforementioned conditions. This paper presents the implementation of a field-oriented control strategy with field weakening. Laboratory testing is carried out on a three-phase permanent-magnet synchronous motor of an electro-hydrostatic shock absorber.