Improved Close Loop Stator Flux Estimation of Direct Torque Control Drive

Abstract In conventional direct torque controlled (DTC) induction motor drive, there is usually undesired torque and flux ripple. In this paper close loop stator flux estimation of DTC with space vector modulation under heavy load at low speed was proposed. First, brief description of stator currents in direct–quadrature reference frame with voltage model. Second, close loop stator flux feedback used through PID controller to correct the value of stator flux estimation and eliminate error. In addition, low pass filter also used instead of pure integration to avoid saturation problem. Finally, simulation results show that the flux and torque ripples are greatly reduced when compared with open loop of stator flux estimation.

[1]  Lixin Tang,et al.  A novel direct torque controlled interior permanent magnet synchronous machine drive with low ripple in flux and torque and fixed switching frequency , 2004, IEEE Transactions on Power Electronics.

[2]  R. Bernal,et al.  High performance torque and flux control for multilevel inverter fed induction motors , 2006, IECON 2006 - 32nd Annual Conference on IEEE Industrial Electronics.

[3]  Bin Wu,et al.  New integration algorithms for estimating motor flux over a wide speed range , 1997 .

[4]  M.F. Rahman,et al.  Direct Torque and Flux Regulation of an IPM Synchronous Motor Drive Using Variable Structure Control Approach , 2004, IEEE Transactions on Power Electronics.

[5]  Lin Chen,et al.  A scheme of fuzzy direct torque control for induction machine , 2005, 2005 International Conference on Machine Learning and Cybernetics.

[6]  Toshihiko Noguchi,et al.  A New Quick-Response and High-Efficiency Control Strategy of an Induction Motor , 1986, IEEE Transactions on Industry Applications.

[7]  H. van der Broeck,et al.  Analysis and Realization of a Pulse Width Modulator Based on Voltage Space Vectors , 1986, 1986 Annual Meeting Industry Applications Society.

[8]  Domenico Casadei,et al.  Implementation of a direct control algorithm for induction motors based on discrete space vector modulation , 2000 .

[9]  J. Amarnath,et al.  Sensorless direct torque control of induction motor based on hybrid space vector pulsewidth modulation to reduce ripples and switching losses-a variable structure controller approach , 2006, 2006 IEEE Power India Conference.

[10]  Wei Xu,et al.  A sensorless DTC strategy of induction motor fed by three-level inverter based on discrete space vector modulation , 2009, 2009 Australasian Universities Power Engineering Conference.

[11]  T.G. Habetler,et al.  A low cost stator flux oriented voltage source variable speed drive , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[12]  Antoni Arias,et al.  Novel direct torque control (DTC) scheme with fuzzy adaptive torque-ripple reduction , 2003, IEEE Trans. Ind. Electron..