Hello friends, I want to regulate the speed of a small AC motor of those simple and small ones of 40 W square plate, the dimer would be excluded because you want it to be stable. It could be the construction of a circuit or some commercial circuit of washing machine, or appliance. thanks for your time, regards -Update: The use I will give is for a magnetic stirrer and basically what I need is a circuit that regulates the voltage of the alternating current but without losing the sinus, I already tried with simple dimmers but they are very unstable. Greetings and thanks

Hi. The only ways you have to control the speed is by electronic means (dimmer), electro mechanical (coil) or mechanical means with pulleys. Washing machines and appliances use conventional dimmers for this. What application will this have? Regards

This theme is recurring here: In the case of motors that have short-circuit rotors, the speed at which they rotate is proportional to what the field does. Well if you want to control its speed you should focus on doing something with the speed of rotation of the field. N (rpm) = (60. fq) / p "in this equ. The only variable is the frequency" N (rpm) >>>> Speed in revolutions per minute. fq >>>>>>>> generator frequency (v; i). p >>>>>>>> number of the stator pole pair. The reference to the "generator" is the one that provides the energy - if there is no synthesizer in between. The speed at which the field rotates is in our case (Argentina) 50 times per second. At what speed will the machine rotate? . I'm going to the ecu. : I do (50 * 60) / 1 = 3000 [rpm]. Simple: if I want to change the [rpm] I have to change the frequency (fq). There are drivers of this type today. Pulse width modulators (PWM) do not modify frequency, they only dose energy; in the same way, but less sophisticated, they make those systems that use triac. In these cases, the variation in velocity is manifested by an effect called slip.

Sorry juite , but what do you mean when you talk about controlling "the speed of rotation of the field"? Is it the same frequency of the generator? What generator do you mean? How is its frequency regulated? Is it a dimmer, a control by PWM? I would like to reach a concrete solution ... Thanks for your help