1. DC Motors Micro Motors Mark Lyon Brent Peterson

2. Outline Motor Overview DC vs. AC Brushless DC Motors Design Considerations Application Considerations DC Micro Motors

3. How a DC motor Works lancet.mit.edu/motor/motor3.html

4. DC vs. AC Motors DC MotorAC Motor http://mot-sps.com/motor/tutorial/blac.html

5. 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

6. 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

7. Brushless DC Motor http://mot-sps.com/motor/tutorial/blac.html

8. DC Motor Torque/Speed http://lancet.mit.edu/motors/motors3.html#torque

9. DC Motor Power/Speed http://lancet.mit.edu/motors/motors3.html#torque

10. DC Motor Electrical Power Constant VoltageConstant Current http://www.4p8.com/eric.brasseur/emamem.html

11. Motor Application Considerations Service Life http://www.micromo.com/03application_notes/tutorial4.asp

12. 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 http://www.micromo.com/03application_notes/tutorial4.asp

13. DC Micro Motors