Slide 1 Slide 2 Slide 3 Slide 4 Slide 5 Slide 6 Slide 7 Slide 8 Slide 9 Slide 10 Slide 11 Product List
Ceiling Fan
Energy start requirements are moving ceiling fan manufactures to move the three-phase brushless DC (BLDC) over the traditional AC motors due to the power efficiency. BLDC are more power efficient compared to AC motors by a factor of 5. For example, a 30VAC motor performance can be replaced by a 5W three-phase BLDC motor. BLDC motors are synchronous motors that have permanent magnets residing on the rotor and coil windings. These produce electrical magnets on the stator of the motor. Electrical terminals are directly connected to the stator windings; hence there are no brushes or mechanical contacts to the rotor such as in brushed motors. Using permanent magnets on the rotor provides the designer with a mechanical advantage, the reduction of both size and weight. BLDC motors feature improved thermal characteristics compared to brush motors and induction motors making them an ideal choice for the next generation of power savings for mechanical systems. Regrettably, the use of three-phase motor control adds additional complexity compared to brushed DC or AC motors and the relationship between digital and analog components becomes very important. It requires a lot more electronics to drive a three-phase motor such as three MOSFET half bridges to complete the inverter circuitry driven by the three MIC4604.
PTM Published on: 2013-09-18