Kudos to speed controllers

I'd like to take exception to the statement that the Synchrotron AC-1 is similar to the Basis unit. Perhaps I should say "was", the AC-1 kit has been withdrawn permanently.

The AC-1 was an original design which used a different circuit topology to achieve different results. It offered a couple of features which are not offerred by any available controller (adjustable phase angle, adjustable harmonic tuning).

The similarlity with the Basis is simply that both are two phase controllers, but that's a bare minimum for any modern controller in my opinion.


Mark Kelly

Dre

I sorry if I came across too strong, it's not your understanding of the situation to which I am taking exception. I guess I overstepped the mark but I'm not keen on my designs being called "similar" to others.

By the way, the reason that the single phase controllers have trouble with different speeds is an inherent feature of the phase shift capacitor. The capacitor value is equal to the square of the drive frequency (in radians per second) divided by the winding inductance. Since the winding inductance is fixed, if the capacitor is correct for one frequency (say 60 Hz for 33) then it must be wrong at any other frequency (say 81Hz for 45).

To answer your question, yes I am working on a new design. For a long time the development of the harmonic tuning concept was stuck because my analysis indicated that the effect should occur at the second harmonic but my measurements showed that third harmonic worked. It finally hit me as I drove home last weekend why this is so; I now have a clear path ahead.

To Jloveys: Your challenge, should you choose to accept it, is to find me a motor whose performance is not improved by a dedicated controller. I will gladly pay you $1000 each for them.

Mark Kelly

JLoveys

I disagree profoundly.

The 124 uses either a shaded pole single phase motor or the Papst three phase (one replaced the other).

Both of these are distinctly improved by a dedicated controller. Of course the controller involved is different in each case.

Let's not turn this into a discussion of vapourware.

I'd prefer to be judged on results.

Mark Kelly

Arrgh! Stupid software! The above was in response to Perrew.

To JLoveys, again I don't wish to discuss vapourware but in general optimal results require that a controller be tuned to the motor it is to run. As long as the parameters required are reasonably close this should be achievable with the same basic architecture.

To this end I expect that the upcoming drive which has been designed for the 301 / 401 would be able to be tuned to the other two tables. The question of whether it would be worth disturbing the tuning for the primary table to accommodate the other two is opne that only you can answer for your situation.