|Researchers at U.T. Dallas have invented a Double Stator Switched Reluctance Motor. It features high torque density, low inertia, and reduced acoustic noise compared with the conventional Switched Reluctance Motor. This motor can be applied in a wide range of industrial applications including aeronautics, automotive, and robotics to name a few. The motor, designed in the REVT laboratory of the University of Texas at Dallas, has the potential to replace the costly permanent magnet motor.
Applications like aerospace, automotive and robotics require high torque to volume/weight ratio machines. Over a decade, the Permanent Magnet Machine has been considered to be the sole candidate, however, the limitation of the operational temperature, relatively high price, and unstable oversea supply of permanent magnet material limits its massive applications. There arises the need for a high torque density machine which is free of permanent magnets.
Conventional Reluctance machine benefits from a relatively simple and rugged structure which make it a conveniently manufactured low cost machine. It has an extend speed range, fault tolerant and modular configuration and the capability of operation in harsh ambient condition. The limited torque density and the acoustic noise during operation are the main obstacles against its replacement for both induction machines and permanent magnetic machines.
The invented motor has a novel, optimized pattern of magnetic flux paths within the electrical machine which yields a superior performance. It has at least twice the torque density of conventional switched reluctance machines. Two stators inside machine cancel the radial force which is the main reason for noise during operation. The shell type rotor results in dramatically smaller inertia. The motor maintains the fault tolerance and the extended speed range capability. In addition, the machine can operate without a position sensor in a wide speed range unlike the permanent magnet machines.
Patent Pending with the University of Texas at Dallas.