DC Motors Micro Motors Mark Lyon Brent Peterson
Outline Motor Overview DC vs. AC Brushless DC Motors Design Considerations Application Considerations DC Micro Motors
How a DC motor Works lancet.mit.edu/motor/motor3.html
DC vs. AC Motors DC MotorAC Motor
AC 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/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 Motor
DC Motor Torque/Speed
DC Motor Power/Speed
DC Motor Electrical Power Constant VoltageConstant Current
Motor Application Considerations Service Life
Motor 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
DC Micro Motors