I have a machine tool with a 1 HP reversible motor. I am looking at implementing speed control by using a zero crossing detector and phase angle controlling circuit. I am planning on using a micro controller such as Arduino to generate the pulses for phase angle control.
The issue is the motor is capacitor start with a centrifugal switch - at lower speeds the centrifugal switch will re-engage.
I am wondering if it is possible, or if there are already designs, to remove the capacitor and centrifugal switch, and replace with another TRIAC to control the start winding?
This could either be controlled by time from the microprocessor, or motor speed if I add another circuit to monitor this (which I may do to display RPM and control an external cooling fan anyway.)