The switched reluctance SR Drive® system comprises a simple brushless motor with a dedicated electronic controller.  Torque is produced by the magnetic attraction of a steel rotor to stator electromagnets.  No permanent magnets are needed, and the rotor carries no “squirrel cage” or windings.



The rotor’s position relative to the stator is detected using a simple hardware sensor or by electronic 'sensorless’ means.  The controller then energizes each stator winding only when it can produce useful torque.  By suitable timing of the stator excitation, the machine can operate as a motor or generator, with exceptional efficiency over a wide range of speed and torque.

Thanks to its inherent simplicity, the switched reluctance SR Drive® system is – both mechanically and electrically – highly robust.  Properly designed and controlled, the motor yields high efficiency across a very wide range of load conditions, and outperforms conventional technologies in most applications – especially where high starting torque, high speed and/or wide constant power speed range are needed. 

Low energy losses in both the rotor and power electronics eases thermal management and enhances reliability and efficiency, whilst the compact stator windings permit great flexibility in motor shape.

In both standard and custom designs, SR Drive® systems offer uniquely flexible, high-performance and cost-effective variable-speed solutions for all applications.




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