Direct torque control of an induction motor using a three-level inverter and fuzzy logic

• Published in: 2004 IEEE International Symposium on Industrial Electronics Vol. 2; pp. 923 - 927 vol. 2
• Main Authors: del Toro, X., Calls, S., Jayne, M.G., Witting, P.A., Arias, A., Romeral, J.L.
• Format: Conference Proceeding
• Language: English
• Published: Piscataway NJ IEEE 2004
• Subjects: A.c. Machines; Applied sciences; DC generators; Design methodology; Direct Torque Control; Electrical engineering. Electrical power engineering; Electrical machines; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Fuzzy logic; Harmonic distortion; induction motor; Induction motors; Inverters; Power electronics, power supplies; Regulation and control; Switches; three-level inverter; Topology; Torque control; Variable speed drives; Voltage; Power converter; Power system harmonics; Power system stability; Harmonic analysis; Asynchronous motor; Fuzzy control; Ac motor; Switching conditions; Output voltage; Voltage; Control method; Energy quality; Selector switch; Harmonic distortion; Electric motor; Multilevel system; Inverter; Direct digital control; Control system; Power electronics; Output signal; Bus system; Voltage source converter; Fuzzy logic; Voltage converter; High power; Torque control
• ISBN: 9780780383043; 0780383044
• DOI: 10.1109/ISIE.2004.1571937

Multilevel inverters, such as three-level inverters, are an emerging technology and are commonly applied to high power motion drives instead of the standard two-level voltage source inverters (VSI). In three-level inverters the blocking voltage of each switch is half of the DC bus voltage, lower dV/dt is generated and the output voltage and current have lower harmonic distortion. In this paper the application of the direct torque control (DTC) strategy is studied for this particular topology. In the three-level inverter the voltage selection possibilities are enhanced since more inverter states are available. Two different control methods have been designed. The first is based on the conventional DTC scheme adapted for a three level inverter. The second is based on the application of a fuzzy logic controller to the DTC scheme to select the appropriate switching state, instead of applying the conventional DTC table. In the simulation results, the novel system based on fuzzy logic shows reduction in torque ripple and harmonic distortion in the stator currents and voltages. Both features are important for applications in motion control where smooth movement and high efficiency are necessary.