Position Sensorless Control of a Motor-Pump-Unit for an Active Suspension in Automotive Applications

The force of a passive damper is strictly dependent on its speed. Therefore, an active suspension is presented in which the force and the speed of the damper are completely decoupled. Furthermore, a close look on its Motor-Pump-Unit is taken. A control schematic for the system is proposed, and the control structure of the permanent magnet synchronous motor is examined from the perspective of the position sensorless control. A simulation is compared to measurements, and measurements with a hydraulic test bench are presented.