Field Oriented or Flux Vector Control of AC Machines

(An Application Example of Mechatronics)

The recent advances in the area of Vector Control (invented in early seven tees also known as Field Oriented Control or Flux Vector Control or Direct Torque Control) for induction machine, the rapid development in the area of Power Electronics, and the existence of power full inexpensive DSPs have made possible the large scale application of variable speed induction machine drives. The induction machine is superior to the DC machine with respect to size, weight, rotor inertia, efficiency, cost etc. Today almost all the industry like Oil, Pharmaceutical, Paper and Textile etc. is using variable AC drives instead of DC drives.

This presentation will focus on the theory behind the controller development for synch AC drives and will consist of two parts.

Part I: Theory of Field Orientation Control

This presentation will introduce with the theory of field orientation, two main types i.e., Indirect Field Orientation (IFO) and Direct Filed Orientation Control (DFO) will be explained. Also the implementation of the control technique in the DSP based system will be discussed as well.

Part II: Advance Concepts in the area of Field Oriented Control, Flux Observers Design and Sensor less control of Induction Machine:

A new technique developed by the presenter and published in the IEEE Power Electronics Trans. Vol. 17, No. 6, pp 1041-1048, Nov. 2002. "A New Current Model Flux Observer for Wide Speed Range Sensorless Control of Induction Machine," H. Rehman, A. Derdiyok, M. K. Guven, L. Xu, will be presented in this part of the presentation.

Biography:

Habib Ur Rehman received his B.Sc. degree in electrical engineering from the University of Engineering and Technology Lahore, Pakistan, in 1990. He received M.S. and Ph.D. degrees both in electrical engineering from the Ohio State University, Columbus, Ohio, in 1995 and 2001. He has published about 4 journal and 15 conference papers. He worked in the Ecostar Electric Drives and Ford Research Laboratory as a design engineer from July 1998 to December 1999. He was involved in the Electric, Hybrid and Fuel Cell vehicles development programs. He joined the Department of Electrical Engineering at the United Arab Emirates University, Al-Ain, U.A.E., in 2001 as an Assistant Professor. His primary research interests are in the areas of microprocessor/digital signal processor based adjustable-speed drives, fuzzy logic and sliding mode control applications to drives. Presently, he is working on the observer’s development for Direct/Indirect Field Oriented motor drives with /without sensor. He has introduced the embedded systems using Microcontrollers, FPGAs/ EPLDs and DSPs in the UAE University.