The Research And Development Of MRAS Vector Control System Based On DSP

As the applications of vector control method for three-phase AC motor are more popular, the speed sensorless vector control method (SVC) has gradually become a hot research objective. In this paper, the SVC in which the motor speed is estimated using MRAS is studied and improved, and its prototype system based on DSP is established.The advantages, development status and direction of the SVC are firstly introduced. By analyzing the mathematical models of the AC motor and its basic vector control equations, the principle of SVC system is introduced. The realization method of estimating motor speed using traditional Model Reference Adaptive System (MRAS) is illustrated and its existing problems are analyed. After that, an improved MRAS is given. Then, MATLAB is used to conduct the simulation study of AC motor's model and MRAS vector control method. The traditional MRAS is compared with improved MRAS as well.A prototype system for AC motor is constructed in order to study vector control system based on DSP and verify the improved MRAS vector control algorithm, the power stage board is developed, some major hardware circuits are designed including rectifier, filter, inverter, power, isolation, voltage sensor, current sensor and protection circuits, etc. DSP programs for the MRAS vector control algorithm and human-machine interface are developed. The prototype system is tested in which the improved MRAS vector control method and the vector control system based on DSP are verified. Finally, a summary for the paper is presented and the further research trend of this subject is proposed.