Simulation And Hardware Design Of Direct Torque Control For Permanent Magnet Synchronous Motor

This paper did a research on the direct torque control of PMSM.After reading lots of articles, this paper introduces some typical control programs for PMSM, and then figure out the benefits of direct torque control, thus tell the development process of direct torque control. To do the research amply, I analysis the math model of PMSM in detail, based on the analysis given the relevant equation under three phrase coordinate system. For precise control, the paper then discussed the theory of coordinate conversion, and build the math model under two phrase rotating coordinates.The paper then discusses the theory of direct torque control for PMSM. DTC can control the torque through control the power angle under the condition that the stator flux stays unchanging. Then the paper introduced the basic theory of switch voltage vector, and analysis the process of control the motor in the way of choosing different switch voltage vectors.Based on the theory analysis, I built the control system in Matlab. The paper gave a detailed presentation of different modules in the control system, and with the help of the simulation work, we can estimate the control effectiveness directly. Considering the stator resistance may bring inaccuracy to the result of flux calculation, I present some projects to improve the flux linkage calculation, and verify one of them with Matlab.At last, the paper did some work on the hardware design, it provides some important diagrams of the control system in details. The design give a convenient reference for further research.