DC Motors Micro Motors
description
Transcript of DC Motors Micro Motors
DC MotorsDC MotorsMicro MotorsMicro Motors
Mark Lyon
Brent Peterson
OutlineOutline
Motor OverviewDC vs. ACBrushless DC MotorsDesign ConsiderationsApplication ConsiderationsDC Micro Motors
How a DC motor WorksHow a DC motor Works
lancet.mit.edu/motor/motor3.html
DC vs. AC MotorsDC vs. AC Motors
DC Motor AC Motor
http://mot-sps.com/motor/tutorial/blac.html
AC Advantages/DisadvantagesAC Advantages/Disadvantages
Advantages Simple Design Low Cost Reliable Operation Easily Found
Replacements Many Different
Environmental Enclosures
Disadvantages Expensive Speed
Control Inability to Operate at
Slow Speeds Poor Positioning
Control
DC Advantages/DisadvantagesDC Advantages/Disadvantages
Advantages Easy to Understand
Design Easy to Control Speed Easy to Control
Torque
Disadvantages Expensive to Produce Can’t Reliably Control
at Lower Speeds Physically Larger High Maintenance
Brushless DC MotorBrushless DC Motor
http://mot-sps.com/motor/tutorial/blac.html
DC Motor Torque/SpeedDC Motor Torque/Speed
http://lancet.mit.edu/motors/motors3.html#torque
DC Motor Power/SpeedDC Motor Power/Speed
http://lancet.mit.edu/motors/motors3.html#torque
DC Motor Electrical PowerDC Motor Electrical Power
Constant Voltage Constant Current
http://www.4p8.com/eric.brasseur/emamem.html
Motor Application ConsiderationsMotor Application ConsiderationsService LifeService Life
http://www.micromo.com/03application_notes/tutorial4.asp
Motor Application ConsiderationsMotor Application Considerations
Audible Noise Electrical Noise Efficiency
Emax = (1 - ((Mf/(Mst + Mf)).5)2
where:
Emax = maximum motor efficiency
Mf = motor friction torque
Mst = motor stall torque
http://www.micromo.com/03application_notes/tutorial4.asp
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