App note: A complete low-cost design and analysis for single and multi-phase AC induction motors using an 8-Bit PIC16 microcontroller

Here’s an application note (PDF!) from Microchip on driving a single and multi-phase AC induction motor (ACIM) using the PIC16F1509 microcontroller:

This document provides a detailed analysis of driving a
single and multi-phase AC induction motor (ACIM)
using the PIC16F1509 microcontroller. Laboratory data
is presented alongside the simulated data in an
extensive reasoning of the entire design. The purpose
of this application note is to show how to add speed
control and soft-start to a single and multi-phase AC
induction motor by using a three-phase inverter circuit.
A low-cost solution is delivered, complete with a bill of
materials (BOM), schematic, code and PCB artwork
files. After analyzing this document, the reader can
easily integrate the reference design and associated
materials into a competitive product. The design does
not include power factor correction because of the
low-cost initiative.