Maximum Efficiency Per Ampere Control of Synchronous Reluctance Motor Sensorless Drives

The maximum efficiency per ampere (MEPA) control strategy stands out as a highly effective means of improving the efficiency of a synchronous reluctance motor (SynRM) drive. This paper introduces an improved approach to optimizing efficiency that treats the motor and inverter as a unified system, ensuring maximum efficiency throughout operation. Diverging from conventional $i_{d}=i_{q}$ or maximum torque per ampere control methods, this approach accounts for both iron losses and inverter losses, while also addressing cross-coupling effects. This is achieved through real-time virtual signal injection, which extracts optimal operation points, and an accurate analytical approach to assess iron losses. Experimental results convincingly validate the effectiveness of this novel methodology.