Long step sensorless control of permanent magnet synchronous machines with extended Kalman filter

This paper presents a long step sensorless vector control of a subsea permanent magnet synchronous machine (PMSM) using extended Kalman filter (EKF) estimation. The PMSM is controlled and driven by an adjustable speed drive (ASD) over 30km transmission lines through one step-up transformer. A typical mechanical load profile is used. An open loop scalar control is applied at the startup and then switched to a sensorless vector control using EKF estimations. A Simulink model is the first step in validating this control strategy. It also validates that PMSM can start at any rotor initial position and achieve stable and reliable sensorless vector control.