Online Identification of Dynamic Resistance and Inductance in Active Magnetic Bearing Application using Current Oversampling

Active magnetic bearings (AMBs) are widely applied in modern high-speed drives. The properties of the electrical ciruit related to AMB dynamics should be known when designing the control, but also the monitoring during the operation of the drive is important. This paper addresses issues in the online estimation of dynamic resistance and inductance in AMB application. The approach considered in this paper is based on current oversampling and slope estimation. The approach is validated with a MOSFET based H-bridge that is connected to RL-load. The results show that the used approach provides reasonable estimation results.