Based On The Three-lever Invert PWM Converter Research Of Direct Torque Control System

Multi-lever inverter is a hot topic in now days, The paper introduce three-lever inverter. Multi-lever has some advantages relative to two-lever inverter(1)The three-lever inverter can reduce distorted output efficiently because it contain more lever(2) The three-lever inverter can be used in high-voltage and big-power variable-speed field.(3)The three-lever inverter Combined with direct torque control theory can be solved or reduced two level inverter combined with direct torque control theory problems such as low frequency pulse.This article is based on TI company’s dedicated motor DSPLF2407chip as the control core, designed a set of three level inverter (neutral point clamp) direct torque control system. Using the system to verify theory of direct torque.The first step is looking up to a large amount of data about theory of direct torque and the emergence and development of the theory of multi-level inverter for understanding, at the same time also understand the subject in the future research direction and hot-spot, also understand the difficulties of the subject and the problem.The second step establish a mathematical model of integration for three level inverter and asynchronous motor, and simply introducing the principle of direct torque theory.The third step analyze the working principle of three level inverter. at the same time, this paper proposes a modified synthetic vectors method and theoretical verification use the simulink tools in matlab software.The fourth step is to build three-level direct torque control system, including the hardware system and software system.Step5is to verify the construction of the system.