Research And Implementation Of PMSM Direct Torque Control System Based On DSP

Permanent magnet synchronous motors (PMSM) have been widely used in the field of motor speed regulation due to its simple construction, high torque/inertia ratio, high efficiency and low loss and the research of permanent magnet synchronous motors system with high performance deserves vast potential and very important social meaning.Direct torque control (DTC) theory has attracted wide attention since it was proposed. Without the decoupling thought, it controls the flux and torque by detecting the stator voltage and current of motors with the help of space vector theory. At first, many researches are in the field of motor speed control. After the successful application of DTC in AC motors, scholars put forward the DTC scheme for the permanent magnet synchronous motor, then quickly becoming a hot research topic.Based on the sinusoidal permanent magnet synchronous motor as the research object, we will study on the direct torque control technology to improve and overcome some of the shortcomings and limitations of the traditional control method, combining with SVPWM technology. The main work is as follows:To study the composition and control principle of direct torque control system, this thesis expounds the spatial distribution relations between the synthesized voltage vector and the magnetic chain, and the relationship between the voltage vector and torque.The method of direct torque control based on SVPWM using symmetry modulation mode makes zero voltage vector distribution more reasonable, effectively improve the asymmetry of magnetic chain, and makes the flux trajectory relative to the traditional direct torque control method more akin to rounded.M-BUS has the very broad application prospects due to its arbitrary topology, interchangeable polarity, accurate and reliable performance, remote power supply, and copy and simple construction.Finally, we can analyze of the direct torque algorithm based on SVPWM in detail, and write programs on the CCS platform. Control algorithm is realized in hardware platforms with TMS320F2812 DSP chip as the core.