wat

Now, I am doing a project about soymilk maker. I have decided to use BLDC motor instead of universal motor in the circuit design. Speed control is needed in my design. Does anyone have any related circuit design about BLDC motor. I cant distinguish which one is helpful or not as I know little about BLDC motor. I will use simple power electronics in my design. Can anyone help me? Thanks~

Someone Electro

This type of motors wont work whith PWM and stuff like that.

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Styx

Err yes BLDC works with PWM

what kind of BLDC is it, is it trapizoidal or sinusoidal flux shaping?

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wat

it is trapizoidal flux shaping...I need any type of circuit diagram about BLDC motor....Can anyone suggest some valuable websites to me?

Styx

Ahh good that will servelty simplify the PWM stage.

A few more questions though (BLDC are not that east to control)


How many phases is it?

you mention speed control: does it need to be a 4-quadrant drive?

equally how accurate does the speed-control need to be?
Can you get away with running the machine open-loop (since a BLDC is just a syncronous machine) or do you also need torque-control (ie do you need to control downto low speed)

if the latter, what speed sensor do you have?
or do you have a position sensor and goin to infer speed?

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wat

Thank you for your comment.
In fact, it is only a dummy project....I need not to buy anything. What I needed to do in this project is to show my supervisor with BLDC motor with speed control. The supervisor knows nothing about motor as he comes from mechanical department. Can anyone provide me any circuit related to BLDC speed control? I have tried hard to find any circuit related to BLDC motor but in vain.
Here are some of my findings:
http://www.atmel.com/dyn/resources/p...ts/doc2592.pdf
http://www.eetasia.com/ARTICLES/2005...EP_REF_WK1.HTM
http://www.fairchildsemi.com/ds/KA/KA2822CD.pdf
There are still more provided in the below website
http://www.microchip.com/stellent/id...GE&nodeId=1483
The aim of my project is to have a simple and cheap circuit. All the designs I found are expensive and complicated...Can anyone give me any suggestion and circuit diagram? Thanks ops:

sarang1_in

Google LB11696 and LB11690. The simplest BLDC circuit I have ever seen. LB11690 comes with mosfet drivers inbuilt. If you are unable to find the datasheets, pm me.
These are Sanyo made ICs and you can get the demo kit also. (Very small and nice)

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