Fan regulation using PIC18f4550

Hello Friends,

I've achieved control of fan speed using triac and zero crossing detection circuit. But there is a constant humming sound in fan because of the frequent turn on and turn off of the fan by spliced AC wave since I am using phase angle control to control fan speed.

On seeing a fan regulator in google, I found that they use an inductor in the regulators available in the market. But on searching in the market, I wasnt able to get such regulators and I dont know the specifications of the inductor and hence could get a custom made inductor too. Can anyone help me in removing that humming of fan?

I need to obtain a smooth continuous wave which is average voltage sort of wave to run the fan. Any suggestions will be appreciated......

**Google doesn't know all the things....so we're here friends**

If you are using controller try PWM technique and give pulses to ur triac and vary pulse width to speed up or sspeed down.