Direct Torque Control Of An Open-end Winding Permanent Magnet Synchronous Motor Fed By Dual Inverters

The multilevel inverter technology has been widely recognized to overcome the voltage limits of power switching converters and effectively improve the utilization rate of dc bus voltage in the area of high power medium-voltage drive systems. What's more, a reduced harmonic distortion and lower voltage regulation factor in the output voltage can be achieved. The direct torque control system of the open-end winding PMSM fed by dual inverters is provided with the advantages of multilevel conversations, meanwhile, this topology structure has certain fault-tolerant capabilities, has good stability and reliability. This paper studies the direct torque control system of open-end winding PMSM fed by dual inverters.According to the circuit topology and characteristic of the motor, the open-end winding PMSM model is established. And based on this model, the structure feature and the effect of the system are analyzed, especially the nonideal EMF's function. For motor characteristic and dual inverter topology, secondly this paper is researched the changes of SVPWM strategy, from the section judgment to space voltage vector's distribution, choice and realization method, which is inhibited common-mode voltage availably. Finally, direct torque control strategy is adopted to eliminate the effect of nonideal EMF in this paper, and one SVPWM strategy is combined to improve the property of the system.In addition, this paper is simulated by MATLAB/SIMULINK based on the above analysis and derivation to get the verification results, which is confirmed the system's advantages. Finally, hardware platform and software were built including current sampling circuits, position detection circuit, drive protection circuit, digital-to-analog circuits. The experiment results show the reliability of the system.