Stator-Flux-Linkage-Calculation-Based Maximum Efficiency Position Sensorless Vector Control of Synchronous Reluctance Motor Considering Iron loss and Cross-Magnetic Saturation

A new position sensorless vector control method allowing the SynRM to operate at maximum efficiency regardless of load and speed is presented. This method entails improving both position estimation accuracy and torque control accuracy by considering iron loss and inductance variations under a stator-flux-linkage-estimation-based loss minimization position sensorless vector control. The validity of this method is verified by experiments on a test machine. In addition, a method to compensate position estimation error caused by inductance variation due to cross-magnetic saturation is investigated. On the basis of some experiments, it is claimed that employing an approximation inductance function that accurately represents the actual inductance characteristics results in obtaining a high compensation effect for position estimation errors, regardless of whether the reciprocity characteristics of mutual inductance are taken into account or not.