3-phase Sensor motor & microcontroller theory

[Maverickmax]

Hi

I need to understand the principle of implementing 3-phase sensorless motor with a microcontroller such as generating sine wave, reading the feedback in order to control the speed.

Does anyone know anything about this area?

Maverickmax

 

[Fish4Fun]

Maverickmax,

There are many resources available online through various power semi-conductor and micro-controller MFGs in their "Applications Notes" such as those found here:

hxxp://www.irf.com/product-info/imotion/sensorless.html

(replace the hxxp: with http: don't remember the rules on live links here)

You might also check Atmel, Motorolla etc. Additionally you might simply do a google search. The topic of polyphase motor control is quite diverse and includes everything from tiny bipolar and unipolar (2 phase and four phase) stepper motors to large industrial work horses like the motors found in train engines. While in theory the design of a polyphase control and power circuit achieves the same objectives accross the entire spectrum of motors, in reality there is a wide range of engineering solutions based on current, voltage, speed control and numerous other enviromental considerations.

If this is purely an academic pursuit, then I might suggest beginning with a simple unipolar stepper-motor controller. There are numerous freeware designs using PIC and Atmel micro controllers, amoung others. While stepper motors do not offer the power or speed of induction motors they allow straightforward, inexpensive experimentation.

Fish