Selecting a Motor for a Planetary Centrifugal Mixer: AC, DC, or Universal?

[avk.dstl]

Hello I am new to this forum, I want to select a electric motor for planetary centrifugal mixer which will mix silicon and phosphor. so the necessary requirements is like it should have high rpm. which motor should I select? AC or DC or universal motor? also I want to know how we can calculate the torque required for revolving a shaft at high rpm. can somebody help me out here?

 

[GT1]

You can find all those motors in high RPM versions. For high RPM AC motor you will need to use inverter which makes this option more expensive. What is the needed lifespan of the motor? If it's about 150-1000hours, I think universal motors are the cheapest (the brushless models). Home mixers usually work with universal motors.
if you need more then few hundred hours you can use DC brushless motors or AC motors (search for spindle motors).
Johnson Electric makes some cheap universal motors (http://www.johnsonelectric.com/mediando/index.php?plugin=search_results&search=Motor" )
The needed torque depends on the drag of your impeller. If you know the power of the motor you use the formula P=T*N (P - power,T- torque,N- rpm, mind the units) .