Speed Control of A Three Phase Current Forced Synchronous Machine Drive Based on A Simple Method

In this paper, a new method is proposed for the speed control of a three-phase current forced synchronous machine drive. This metohd is based on the use of an approximate constant commutation safety margin angle in the output thyristor bridge of the drive system as well as on the compenastion of stator magnetization reaction. The commutation process in the output converter of the machine drive is naturally performed by means of the rotor induced emfs in the stator winding. In comparsion with other speed control methods reported for these types of drives, this method is more stable and robust. In additon, higher efficency and power factor can be achieved for the synchronous machine drive through this method. The impacts of rotor damper windings on the drive system performance are also explained in the paper.