Disclosure; I represent a distributor of MagnaDrive.
re jraef comment re a former member; if it was Gus D'Almaeda, he unfortunately passed away a few years ago. He was employed by a large oil sands producer and recognised the potential in certain applications. The original fixed speed couplings have been around for quite some time and were sold mainly through bearing houses, and there were some inappropriate applications; perhaps the one referred to by jraef was one of them.
The adjustable speed drives are more recent. There are some significant differences to eddy current couplings, with some significant mechanical benefits regarding misalignment tolerance, vibration reduction, reliability, simplicity etc. The report referred to was accurate for the tested unit, however the test set up was smaller than the typical drive, so that some losses were higher than in more typical applications. In a comparison to VFDs , there are other losses that should be taken into consideration, which make the efficiency of the Magnadrive much more comparable. However, in analysis of a project, all factors and costs should be considered over thhe expected life of the project. Suffice to say, I have been involved with several projects where the end user is delighted ( his word ). Are they suitable in all applications ? No, of course not, but in many situations they are well worth considering.
mac