At 02:17 AM 16/10/2009, you wrote:


... the power handling ability of the motor depends on these things:

>motor thermal capacity
>motor max temperature
>motor cooling
>motor efficiency
>magnetic saturation (limits max magnetic field)
>winding inductance (limits rotational speed and causes phase shifts
>between current and magnet positions)
>bearing and rotor speed limits
>
>In turn, motor efficiency depends on:
>
>rotational speed (faster increases most forms of loss)
>eddy current losses in iron
>hysteresis loss in iron
>winding resistance (at the AC commutation frequency)
>motor current
>bearing drag
>air drag inside motor
>
>You care about power out..

Actually he wants to maximize the ratio of power out to weight.

Clearly the very best results are to be had in space where weight ~= 0.

>Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com



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