The world's simplest motor for variable speed control? The Cyrano motor, a PM-biased SR-motor of high torque density

The paper presents a very simple and inexpensive variable speed electronic motor fed with pulsating DC current, which is produced by a power converter using just one or two power switches. The motor has high torque density and a single predetermined direction of starting rotation. Recuperative braking and in certain circumstances electronic speed reversal is possible.<
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