Investigation and analysis of torque generation mechanism of reverse salient permanent magnet synchronous machine

In this paper, the torque generation mechanism of the reverse salient permanent magnet synchronous machine (RSPMSM) is investigated. The magnetic equivalent circuit (MEC) and the equivalent reluctance of different magnetic circuits are used to determine the air-gap magnetic density without slotting. By incorporating the influence of the slotted Carter factor, a model for the air-gap magnetic density at no-load is deduced and compared to finite element analysis results. The strong agreement observed between the analytical method and finite element analysis validates the precision of the proposed methodology. Moreover, the Maxwell stress method is employed to analyze and demonstrate the genera-tion mechanism of electromagnetic torque. The contributions of the fundamental wave and each order harmonic to the torque components and their proportions are determined. This analysis provides valuable insights into the generation process of torque in the machine. Additional prototype experiments were conducted to verify the validity of the theoretical analysis and finite element simulations. The experimental results further confirm the accu-racy and validity of the proposed methodologies.