varying speed of AC fan using microcontroller

Hey guys. I am looking for a suitable hardware circuit for controlling AC fan using a microcontroller.

We need three modes of speed. Low, medium and full.

I know triacs are one way for this, but I am looking for some IC or module that could do the job.

Any suggestions will be appreciated.

Thanks and Regards,

You need to know more about your fan , size, current , motor type ( some cannot be speed controlled easily ).
Do a bit of research here first .

AC motor speed is tricky to control. Make your life easier and use a dc motor.

Yes I am doing a research, and all I have found is that I need to use triacs whatsoever. Also, DC motor option is good, but it is not in my domain to decide this. So I need to focus on AC fan.

Also, The size and all this stuff is important, but any general guidelines would be good as well.


You need to find out what sort of AC motor you have before looking at bits to control it - it’s a bit like buying a spanner before you know what size nut you have to undo .

I expect , in a fan , it’s a reluctance motor - which you cannot speed control by altering the input voltage .

OK i will see which motor is it, then I will get back to you.