INVESTIGATION OF THE DYNAMIC PERFORMANCE OF HYSTERESIS MOTORS USING MATLAB/SIMULINK

The hysteresis motor starts by virtue of hysteresis losses induced in its rotor. Hysteresis motors are widely used in small motor applications. In this paper the dynamic performance of hysteresis motors is investigated. A mathematical model is applied to analyze the transient and dynamic stability of this electrical machine type. The transient and dynamic stability studies examine the performance of the motor under transient condition and when the system is perturbed about some operating point, ie , small-signal analysis. In addition, in this paper, the mathematical based d, q axis model is incorporated in Matlab/Simulink tools for analysis and simulation purposes. This incorporation is considered a trend in applying new computerized tools in electrical machines simulation, design and analysis. The model offers a tool for studying the dynamic stability of the hysteresis motor for small-scale perturbations such as changes in motor’s input supply voltage or frequency or in its output load torque as well as under other various conditions. The hysteresis motor is a well-known type electrical machine. The construction of the hysteresis motor is of stator and rotor parts. The stator has conventional stator windings while the rotor comprises a solid rotor hysteresis ring of permanent-magnet material with no teeth or polar projection. The starting of the motor is due to the hysteresis losses induced in the rotor of the motor. The starting current is in the range of 180 to 200% of its full load current, and it can pull into synchronism any load inertia coupled to its shaft. Due to its quiet operation, this motor gains a wide range of industrial applications. The quasi-state analysis of the hysteresis motor had been investigated in [1–3]. The dynamic performance of hysteresis motors becomes important for the optimum design and stability performance. There has been little contribution in the literature on the dynamic characteristics of the hysteresis motors [4–7]. The application of new simulation and analysis techniques using different computer software such as Matlab/Simulink in simulation and analysis of conventional electrical machines has been reported in [8–10]. In this paper the application of Matlab/Simulink computer software is used in investigating the small signal stability performance and the non- linear simulation of the hysteresis motor. Such application can be considered as a trend for investigating the dynamic performance of this specific motor type.