High-Strength Rotor Design for Ultra-High Speed Switched Reluctance Machines

High speed machines are gaining popularity in more and more applications. Besides permanent magnet (PM) machines, switched reluctance machines (SRMs) are very competitive candidates for high-speed applications in high-temperature environments due to their single material rotor without PMs. However, the conventional rotor geometries of SRMs are not suitable for the ultra-high speed applications. In this article, a novel high-strength, high-torque-density, high-efficiency rotor design for the ultra-high speed SRMs is proposed. First, a three-dimensional finite-element analysis is conducted to calculate the von-Mises stress distribution of the proposed rotor and shaft. Then, in order to improve the bonding and robustness of the design, proper high-strength adhesives are used and modeled based on the cohesive zone model. A parametric study is conducted to find the optimal length of the rotor stack. A thermal stress case study is also conducted. Finally, several prototypes are built to validate the manufacturing feasibility of the proposed design.