Technical Wednesdays Are Here!
Today’s Feature: The Nitty Gritty Details of the Motor
Are you ready for the nitty gritty details of the motor? Engineer and UMsolar Crew Chief of 2009 John Federspiel explains his favorite piece of the car.
If you’ve ever stopped by at a UMsolar event and asked the question “how does it go?” or “where is the motor?” you’ve probably gotten a response that went something like, “the solar car uses a 98% efficient CSIRO, DC, 3 phase, in-hub, brushless motor.” For those of you who didn’t immediately nod and think to yourselves, ‘of course’, John’s here to break it down for you.
CSIRO motors are small, lightweight motors. The lightness allows the team to further minimize drag and increase the aerodynamic features of the car. CSIRO stands for the Commonwealth Scientific and Industrial Research Organization and is Australia’s national science agency. This postage stamp-sized, 2 minute video explains what CSIRO is all about. But what does the rest of, “CSIRO, DC, 3 Phase, in-hub, brushless motor” mean, you ask? Read on.
DC stands for Direct Current. Direct current is the type of energy provided by the battery or by a solar cell. Direct Current is in contrast to AC, or Alternating Current, which is the type of energy that comes out of your outlet at home. One major difference is that DC current always flows in one direction, whereas AC current alternates between going forwards and backwards dozens of times per second. Still awake?
3 Phase describes the way in which the power is applied to the motor in order to achieve rotation. This spiffy page gives you a moving model of 3 Phase.
In-hub means the motor is incorporated directly into the wheel as opposed to having a transmission that transfers the motor’s power to the wheels. In-hub motors allow for greater efficiency. And now on to the very last term…
Brushless refers to the type of motor. In brushless motors the electrical windings are stationary and the housing has permanent magnets that rotate with the wheel. You can read on about the more technical aspects of brushless versus brushed motors here.
Do you still have questions about the motor? Post them up! John’s happy to answer them.
Also, if you have a topic you’d like to see explained next Wednesday, post that, too