2 & 4 pole brushless????
01-14-2006, 11:51 AM
#1
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2 & 4 pole brushless????
heya
can someone please tell me what the hell is the difference between 2 and 4 pole brushless motors i did a forum search,got nuthing,searched the net for 2 hours..nuthing,can someone help. because i wouldnt have a clue [&:]
can someone please tell me what the hell is the difference between 2 and 4 pole brushless motors i did a forum search,got nuthing,searched the net for 2 hours..nuthing,can someone help. because i wouldnt have a clue [&:]
01-14-2006, 01:32 PM
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RE: 2 & 4 pole brushless????
In real simple terms, a 2 pole brushless DC motor uses 2 opposing charge magnets on the rotor. One having a north and the other having a south polatiry.
I found this flash animation to help you understand the theory:
http://www.servomag.com/flash/2-pole...ldc-motor.html
As you can see, the decoder circuit energizes the appropriate windings of the stator in sequence to create a like magnetic field to the pole presented by the rotor. Since the magnets of like polarity push away from one another, the rotation is initiated, and controlled by the attraction of the opposite polarity magnet to the energized winding. The process simply repeats itself over and over from one winding to the next, thus sustaining the rotation.
In a 4 pole brushless DC motor, the rotor is divided into 4 equal quadrants, of opposing polarity. There are 2 north, and 2 south poles on the rotor. Unlike the 2 pole motor, the windings on opposite sides of the stator energize at the same time, to create the same push-pull magnetic field we saw in the 2 pole motor. The advantage a 4 pole motor has over a 2 pole is smoother operation, and reduced power consumption.;
Please see this flash animation for reference of a 4 pole motor:
http://www.servomag.com/flash/4-pole/smi-motor007.htm
I found this flash animation to help you understand the theory:
http://www.servomag.com/flash/2-pole...ldc-motor.html
As you can see, the decoder circuit energizes the appropriate windings of the stator in sequence to create a like magnetic field to the pole presented by the rotor. Since the magnets of like polarity push away from one another, the rotation is initiated, and controlled by the attraction of the opposite polarity magnet to the energized winding. The process simply repeats itself over and over from one winding to the next, thus sustaining the rotation.
In a 4 pole brushless DC motor, the rotor is divided into 4 equal quadrants, of opposing polarity. There are 2 north, and 2 south poles on the rotor. Unlike the 2 pole motor, the windings on opposite sides of the stator energize at the same time, to create the same push-pull magnetic field we saw in the 2 pole motor. The advantage a 4 pole motor has over a 2 pole is smoother operation, and reduced power consumption.;
Please see this flash animation for reference of a 4 pole motor:
http://www.servomag.com/flash/4-pole/smi-motor007.htm
01-14-2006, 09:39 PM
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RE: 2 & 4 pole brushless????
yeah...with maybe 9 and 12 leading wires respectively! lol! serious now, i think that the market and manufacturing know-how is a bit premature [for the moment] regarding high-power multi-pole brushless motors, although theoretically they should get a lot better. one can make a parallelism and within very simple and short terms could say that 2-pole/4-pole/multi-pole brushless motors are something like the phases of AC motors [more phases = higher efficiency but more complex design]. in fact, brushless motors are more of AC motors than DC ones! [although that is not widely known...]
