Implementation of a new fast direct torque control algorithm for induction motor drives

Induction motor (IM) drives based on direct torque control (DTC) allow high dynamic performance to be obtained with very simple control schemes. The conventional DTC has two main drawbacks. The first one is the variation of the switching frequency according to the amplitude of the hysteresis bands and the motor operating speed, whereas the second is that the selection of voltage vectors is not optimised inside the flux hysteresis band to give fast torque response, because of the nature of the hysteresis controllers. This study proposes a new DTC method for IM, which enables fast torque response and constant switching frequency. This is achieved by optimising the selection of the voltage vectors to give maximum rate of torque increase. Simulation and hardware implementation results show that both the torque and speed responses are faster than the old method. In addition, the effect of variation of the IM parameters on the system performance is taken into consideration.

[1]  Peter Mutschler,et al.  Direct mean torque control of an induction motor , 1997 .

[2]  R. Krishnan,et al.  Study of Parameter Sensitivity in High-Performance Inverter-Fed Induction Motor Drive Systems , 1987, IEEE Transactions on Industry Applications.

[3]  H.Y. Zhong,et al.  A new microcomputer-based direct torque control system for three-phase induction motor , 1989, Conference Record of the IEEE Industry Applications Society Annual Meeting,.

[4]  M. P. Kazmierkowski,et al.  Improved direct torque and flux vector control of PWM inverter-fed induction motor drives , 1995, IEEE Trans. Ind. Electron..

[5]  Marian P. Kazmierkowski,et al.  Direct torque control of PWM inverter-fed AC motors - a survey , 2004, IEEE Transactions on Industrial Electronics.

[6]  Ranjan K. Behera,et al.  Improved direct torque control of induction motor with dither injection , 2008 .

[7]  L.M. Tolbert,et al.  Direct torque control of induction machines using space vector modulation , 1991, Conference Record of the 1991 IEEE Industry Applications Society Annual Meeting.

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

[9]  S. Mahmoud,et al.  Improved direct torque control for induction motor drives with rapid prototyping system , 2006 .

[10]  M. Depenbrock,et al.  Direct self-control (DSC) of inverter-fed induction machine , 1988 .

[11]  Dinkar Prasad,et al.  A simple hardware realization of switching table based direct torque control of induction motor , 2007 .

[12]  F. Blaabjerg,et al.  A modified direct torque control (DTC) for induction motor sensorless drive , 1998, Conference Record of 1998 IEEE Industry Applications Conference. Thirty-Third IAS Annual Meeting (Cat. No.98CH36242).

[13]  Shuxi Liu,et al.  An improved direct torque control of induction motor with current hysteresis band , 2008, 2008 World Automation Congress.