An old film to bring you up on the basics. Weirdly, physics don’t change.
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A reluctance motor is a different breed. It is a form of a brushless motor. However, the brushless motors we use in the RC hobby, the number of stater teeth (each iron segment that is wound with copper wire) will always be 3,6,9,12…; A number always divisable by 3. Magnets will always number 2 or 3,6,9,12 some number divisable by 3. Each magnet is considered a pole. So, a 6 magnet motor is called a 6 pole motor.
The cause of investment into the development of Reluctance motors is communist China produces most of the materials described as rare earth that are used to produce modern high power magnets. China has limited the export of these materials and magnets in order to help China monopolize permanent magnet motor production. The reluctance motor does not need any of these materials and is hence much cheaper to manufacture. Also our ability to produce motors in the USA would not be hindered by the unholy alliance between government and business as is so common in socialist/communist states. Regardless of the type of government, anytime governments stick their fingers into business, supply problems and shortages ensue. Perhaps these developments will stifle the anti-capitalists this time. Sustained monopoly’s are only possible when governments collude with business (or nationalize industry). It’s an interesting side note to mention there have never been any long lived monopoly’s that were not created and maintained by government regulation.
According to HEVT the spot price for neodymium increased from $19 a pound in 2010 to $129 a pound in 2011.
Many times technologies are developed and press releases fly all over the internet. These products offer great promise yet often the creators are just looking for somebody to buy the technology and when they are unsuccessful (most of the time) we never see the great new products. This development strikes a different tone with me, I feel this very well could be the beginning of a new paradigm shift in motor technology. Lets just hope it makes it down to us modelers sooner rather than later.
Learn more about Switched and Synchronous variations here: Reluctance Motor Wiki
Many photo’s and drawings: Google Images Reluctance Motors