Performance Analysis and Parameter Sensitivity of Cageless Pm-Assisted Synchronous Reluctance Generator

This study investigates the performance characteristics and parameter sensitivity of a cageless permanent magnet–assisted synchronous reluctance generator (PMASRG) with the aim of evaluating its efficiency, torque behavior, and operational stability under varying electrical and mechanical conditions. The research addresses critical problems associated with reluctance machines, particularly low power factor and torque ripple, by integrating permanent magnet assistance and employing the classical d–q transformation technique for dynamic analysis. Using mathematical modeling based on d–q axis voltage equations, flux linkage relations, and electromagnetic torque formulations, simulations and sensitivity analyses were performed to quantify generator performance across different operating points. Results show that the generator achieves a maximum electromagnetic torque of approximately 3.75 Nm at a rated current of 6.5 A, with reluctance torque contributing 0.77 Nm at a current angle of 45° and permanent magnet torque peaking at 3.41 Nm at 90°. Power generation analysis revealed that at the rated speed of 1500 RPM and 10 A current, the generator produces nearly 1500 W, exceeding its nominal 1000 W rating, demonstrating strong variable-speed capability. Efficiency analysis indicated a peak efficiency of about 92% at 800 W before declining due to copper losses (I²Rs), which reached approximately 134.2 W at high loads. Power factor analysis showed stable performance around 0.85 at the optimal current angle of 45°, confirming that permanent magnet assistance mitigates the low power factor typically associated with pure reluctance machines. Sensitivity analysis revealed that a 10% increase in d-axis inductance (Ld) improves power output by roughly three times more than an equivalent change in q-axis inductance (Lq), highlighting the importance of rotor design optimization. The study concludes that the cageless PMASRG offers high efficiency, strong torque density, and operational flexibility, making it suitable for modern renewable energy and variable-speed applications. Policy recommendations emphasize the need for optimized rotor saliency and thermal management strategies to maximize performance and reliability. Future work should focus on experimental validation and control strategies to further enhance stability and energy conversion efficiency.