The rotor follows the frequency and phase sequence rotation of voltage applied to the motor until it reaches the desired speed.

The silicon-controlled rectifiers in the power converter are used to control the voltage and current applied to the motor armature.

The source and load converters respond to a small reference voltage increasing the frequency applied to the motor until it reaches the desired speed.

The cycloconverter is used to increase the voltage applied to the motor until it reaches the desired speed.