Small AC or DC motor is very common in domestic unit.
AC. 1 phase for Washing machine, Hair dryer...
AC 3 phase . Building water pump, lift motor..
AC in 3 phase, easy to speed control.afterwards to control the water pump flowrate.
DC motor, 24V very common, e.g. operation shunt trip motor for electricl switch (e.g. up to 1200A)
AC motor: induction motor & Synchronous motor..
Induction motor (wound -round type & squaal cage type)
DC motor: Shunt motor, serial motor, etc..
Inductries:
DC motor e.g. Rail, Tram,..It easy to control the starting torque..
AC motor, Most of water pump, include water transfer and distribution system..
don't say which one better, because, it must be subject to what kind of application?
AC 摩打 = 體積細,維修容易,速度穩定,馬力大,價錢便宜,用于裝置機械,如要調速就要用變頻器,扭力弱。
DC 摩打 = 扭力強,容易控制速度,可以將交流電整流后用或用電池直流電,用經常移動既機械如起重機,掃地機等,如果可以用電池車都可以,但維修費高。
有D摩打係可以交直流雙用既
2007-09-24 22:37:18 補充:
小型既 AC Motor 無錯都是電感應式(轉子部分是沒有繞線的),但係大型既 AC Motor 唔一定係電感應式(轉子部分是沒有繞線的),比如繞線轉子滑環式 Slip Ring Wire Wound Rotor Motor 就有電刷,需要定期維修,參考http://www.lmphotonics.com/slipring.htm