Switched Reluctance Motors (SRMs) is one of the synchronous machines which wereattracting more and more attention in past year due to development in power electronics. On of this motors charactristics is their robust structure and low manufacturing costs. Also the windings are only concentrated in stator poles and there are no conductors or magnets at the rotor poles.Thus the rotor of SRM is the simplest of all electric machine rotors. Simplicity makes the SRM inexpensive and reliable. Moreover with increasing poles and controlling appropriately, the drive can achieve to high torque and high speed. So this motor can be a good candidate for electrical vhicle. The SRM rotor and stator are saliently, sothese machine characteristicsare highly nonlinear. So the complexity of controlling is one of the machine problems. The most commonly method used for controlling SRM’s current is the Hysteresis method. However, because of this controller disadvantages, pi current controllers are used in some application.The PI contloller are usually designed for a specified point and the performance of controller is not appropriate for other points. Hence, pi gain scheduling controller (pigs) is often used instead of fixed gain pi controller. This thesis attempts to investigate the control of the switched reluctancemotor from the motor's structure properties, model equations, operation principle and power converter topology.After the general introduction of SRM, different methods for pi current controller gain adaptation are investigated and the performance of controllers is compared. Based on these methods, an improved gain adaptation for pi gains is proposed. The proposed method is simple and proves to yield a satisfactory performance. In proposed method the lookup table and difficult analytical method are eliminated so that the controller has good performance.The motor flux linkage appears to be a nonlinear function of stator currents and rotor position. Since SRMs are highly nonlinear, usual pi controllers don’t yield a satisfactory performance. To demonstrate the performance of the controller and to compare the different controlling methods, simulation results are presented. The effects of variable dc-link voltage on current controller, especially at high speeds, are also investigated. Simulation results are presented to verify the performance and viability of the proposed current controller. Simulations are done using MATLAB-Simulink package.A hardware prototype is implemented with digital signal processor to verify the simulation result running at 5 kHz switching frequency. The experimental results indicate the good performance of proposed method.In the end, there is a summary of thesis and suggestions for further studies. Keywords: Switched Reluctance Motor, Current controller based on back-emf, PI controller, Variable dc-link.
