The ttartihg methods of synchronous motors are discussed generally. A new technique based on an open loop control starting system of a synchronous motor fed from a voltage source inverter emplementing Gate Turn Off thyristors (G.T.0) and a single phase half controlled bridge rectifier is presented. An accurate model of the Rectifier-Inverter-Motor set is developed to simulate the motor response during startup. A comparison between the fixed frequency starting and the variable frequency starting is presented.

While numerical analysis techniques, such as a finite element analysis and boundary element analysis, have been presented as an accurate tool for design and simulation of Switched Reluctance Motors, they do not give any method of a systematic design procedure with a minimum computational effort. Besides, They have not introduced any matching with the conventional design approaches used in classical machine design. This paper presents a systematic design procedure based on magnetic circuit analysis and standard proportion among motor parts to determine the motor dimensions. The proposed procedure is generally structured to run on personal computers to design and simulate any permissible specifications, in a few minutes. It has been shown that, for fast and more traditional design, no numerical techniques are needed, since the magnetic circuit analysis is more simple and complete in itself. The proposed program is not limited only to the motor iron and copper dimensions, but also estimates many of performance indices such as output power density, generalized power factor, losses and efficiency.

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Many types of drives used in positioning systems need high performance controllers to achieve good dynamic performance in the presence of system uncertainty and complex environment. Traditional control schemes like PID can not meet these requirements. On the other hand, a conventional fuzzy logic controller can usually control a nonlinear system more efficiently, and provide better performance than PID controllers in terms of shorter rise time and smaller over shot. Unfortunately, the traditional fuzzy logic controller cannot improve the steady state performance for time varying systems. To overcome this drawback, the integral of the error of the system is taken in consideration. This paper presents a hybrid of the conventional PI compensator with fuzzy logic controller to improve steady-state and dynamic accuracy of the servo position control system. The results obtained indicate that the proposed controller has an excellent position tracking performance compared with both traditional PID controller and fuzzy PD controller.