| The paper entirely summarizes the actuality and development of Direct Torque Control (DTC) system of induction motors, and detailed introduces the basic theory and principles. According to main performances in the DTC are show by simulation experiment, the application of intelligent algorithms in the DTC is presented and experiment approve the validity.Direct torque control (DTC) is a kind of AC timing technology. Commonly, motor mathematical model is constituted by voltage equation, flux equation and torque equation. Traditional control strategy which dynamic control effect is of a sort and delay problem exists in to extent. So it is very difficult that traditional control strategy actualizes real-time, veracious and adaptive control.Grey prediction control seeks system movement rule by system behavior data in this paper. It can predict system future movement trend by the movement rule to confirm relevant control decision-making which is used to actualize veracious prediction control.For the sake of obtaining optimization prediction and adjusting performance, the coefficient of combining prediction is optimized by genetic algorithm (GA), at last the best control program is gained through fuzzy inference. This method avoids the time delay response of the system.The paper analyses the control theories of induction motor in detail, the soft program is designed at the pain of TMS320F240 DSP setting. The software of the control system is complied with embedding Assemble Language in C program to accomplish the improved DTC algorithm design. This software has realized functions of the sampling of stator phase current, calculating of the phase voltage, the observing of stator flux and the output of switching signal etc.Experiment results show the combining prediction fuzzy controller based on GA has good performance and is more effective than traditional fuzzy controller. The system can get more satisfactory results of dynamic response,strong anti-interference and strong robustness.
|
PDF Full Text Request