Start of single phase AC motor - theory and practice

Hello guys,
I have a question about how AC motor starts.
Please read file in attachment and comment.
Thanks

Check this site: http://www.lmphotonics.com/single_phase_m.htm

pandiani, there are lots of different kinds of single phase AC motors, each with a different scheme for getting the motor started.

In the most basic form, you need to create a second AC phase that is offset in time with the primary AC power phase. Once you have created this second phase, you use it to create a spinning field in the stator which drags the rotor around just like in a three phase motor.

Many different schemes have been used to create this second AC phase, some of purely inductive, some using capacitors and inductors, and some using simple magnetic methods as in shaded pole motors.

Most of these develop rather poor levels of torque at start so that becomes a key application issue when selecting the right design of single phase motor.

This is probably one of the better pieces of literature for learning about basic motor theory. http://www.aosmithmotors.com/pdf/brochures/bulletin3100/ACDC.PDF

If you go to the section on how an AC motor works you will get the basics, then go to page 26 for a great description of the available types of 1 phase motors, how they work and what their advantages / disavantages are compared to each other.

Thank you, very helpful!

How deep do you want to go?

You can always find a state space model of an AC induction motor in the internet. There are places like www.ti.com that have application notes on how to control AC motors using their DSPs. Actually, I think that just about every DSP manufacturer has an application note on how to control an AC motor using their DSPs.