Re: Any ideas for large motor, and electronics


Bob Minchin wrote in message ...
>
>Michael wrote in message ...
>>Hi,
>>
>>As some of you may know, I'm building a model submarine.
>>
>>It will be huge with a displacement of around 500kg and a length of 4m.
>>Having worked out a rough idea as to the size of the motor required, 3hp.
>>I'm now looking for suggestions. Sites like technobots don't stock ones
>>large enough and so I'm struggling to find an answer.
>>Then there is the matter of how to control the speed. Ideally I'd like
>>proportional control.
>>
>>So, does anyone know where I can find a motor, ideally with the
electronics
>>to control it? The onboard power will be provided for by two 12V
batteries,
>>of which the AH is still undecided.
>>
>>Thanks
>>
>>Michael
>>
>>
>Hi Michael,
>
>You might find it interesting to consider a mains 3 phase motor.
>
>Before you delete this reply as a bit wacky, please read on.
>
>Motor inverters are quite cheap now especially secondhand on ebay. All of
>these rectify the mains to form a DC source from which variable frequency 3
>phase AC is synthesised by electronic switches.
>I would think it possible to have a high voltage battery ( much more
>efficient at these powers than low voltages and huge current draw) and feed
>this in the AC inputs to the rectifiers in the inverter.
>Most of the inverters can be controlled by buttons on the module, remoted
>switches and knobs or by RS232/485 digital commands from a microprocessor.
>This may be a bit exotic for your project and maybe a skills mismatch but
>I'll throw it in as an idea.
>
>It is *just *possible that I can get hold of programming info for Siemens
>Micromaster inverters as someone I work with used to work for Siemens
>Automation and Drives.
>
>Good Luck
>
>Bob
>
>
>

Erm -Dunno why this suddenly reposted itself. Apologies
It won't let me delete it either!

Bob


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