A maximum torque per ampere vector control strategy for synchronous reluctance motors considering saturation and iron losses

In recent years, the synchronous reluctance (SyncRel) motor received much attention for many applications due to its simple and robust construction. When using the principle of vector control, it is possible to achieve optimal operation of SyncRel motors for all loads and speeds. A suitable control strategy can be implemented to achieve maximum torque per ampere, high efficiency and maximum power factor. However, the control of a SyncRel motor is highly affected by both magnetic saturation and high iron losses. A new strategy to achieve maximum torque per ampere (MTPA) is proposed in this paper. The motor behavior under vector control is analyzed considering both saturation and iron losses. A simple relationship between the developed torque and d-axis current has been obtained for MTPA conditions. After experimental check, the obtained relation has been implemented in a vector control algorithm. The proposed control strategy has been successfully implemented with the aid of an experimental setup.