Line-start performance of single-phase synchronous reluctance motor with controlled capacitor

This paper reports the effect of values of starting and synchronisation (running) capacitors on the line-start performance of a single-phase cage-rotor synchronous reluctance motor. The d-q rotor reference frame dynamic equations were used to select the values of capacitors best suited for starting and running and it is shown that for a near-instantaneous starting, the capacitances should be varied (within the selected peaks) in line with the machine speed error. One single three-terminal capacitor device controlled by speed error signal is found to be very useful in realising a faster acceleration than obtainable with conventional and other known methods. Peak torque pulsations and current drawn by the main winding were found to be reduced, suggesting a more efficient motor drive performance. Simulated and experimental results bear a resemblance.