Hey guys! I need your help.... I know just one point that DC motor can control speed even with load but AC motor can't. I want more points...... could u help me???? It would be gr8 if u could tell me the name of the site from where i can get some info. about this.......Thankyou in advance!
ac motors are instantaneous but they dont give u much power but when it comes to dc motors they deliver u much power but thats too complex to run a dc motor and also the dc motors give u contant speed also
DC motors are also used where controlling speed and torque are important. Also the starter motor in a car runs off a (DC) battery and the DC motors that operate windows and seat positions in a car are small and powerful because they use compact powerful permanent magnets. The battery driven electric DC motors in many forklift trucks permit portable power (no power cables). Golf carts use portable DC batteries too.
Usually, DC have a higher degree of efficiency compared to some AC motors...like shade pole versions (like fan motors). Plus like the previous statements...DC are easily controlled but are a more complicated piece of machinery. AC motors are simpler construction, but need special drives to control speeds. Plus DC's with brushes tend to be limited by the brushes themselves. They wear out. AC motors with a good set of ball bearings practically last forever.
The main advantage of a DC motor over an AC motor is that it can operate directly from from a battery. The speed of a DC motor can be controlled with a less complicated control unit that the unit required for an AC motor. Only the armature voltage needs to be controlled.
