| The Switched Reluctance Motor System has many advantages, such as excellent performance of speed adjustment, simple structure, lower cost and high reliability, but every coin has two sides. Its unique structure also leads disadvantage such as its serious torque ripple. The system needs different control strategy for different speed zone because of its highly nonlinear characteristic. Therefore its control scheme is very complex. The direct torque control is famous for its unique control concept and simple scheme. The thesis is aimed to apply the Direct Torque Control on the four-phase Switched Reluctance Motor.An expression of instantaneous torque is deduced from elementary function. In this paper, select eight effective voltage space vector based on the characteristics of four-phase 8/6 switched reluctance motor. Based on the principle of Direct Torque Control, the torque can direct control and keep constant of the amplitude of stator flux by rational selection of the effective voltage space vector. The MATLAB simulation results show that the torque ripple has been control by Direct Torque Control, and the locus of flux linkage for stator is a circular, the waveform of stator current and flux changed smoothly.In this paper, compound control strategy of Fuzzy and PI control has been adopted. It provides reference torque for Direct Torque Control loop. Simulation of Fuzzy control, PI control and Fuzzy-PI control show that Fuzzy-PI control is superior to single control. The article describes mainly the weighted average method for Single-value model fuzzy controller. It is easy calculation and has a high precision.
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