Vibration Control for an Implantable Blood Pump on a Bearingless Slice Motor

Abstract

Implantable left ventricular assist devices are powered by batteries. Their limited capacity has to be used as efficiently as possible. At the example of a MAGLEV centrifugal LVAD it was demonstrated that a drastic reduction of power consumption (50% in the bearing) could be achieved by vibration control. A vibration controller design for the non-linear plant is discussed, simplified and extended to four harmonics. A new phase shift strategy is presented to eliminate time-consuming matrix operations. Based on this simplification the implemented algorithm applied on the bearingless slice motor allocates little memory and requires short computation time. Additionally, the decreased control currents lead to higher control margins of the power amplifiers and therefore to improved robustness.