Design Support


The importance of Digital Motor Control (DMC) has grown gradually. As Digital Signal Processors have become cheaper, and their performance greater, it has become possible to use them for controlling electrical devices as a cost effective solution. Some relatively new methods such as speed sensorless field oriented control utilize this enhanced processing capacity. This document discusses the implementation of a sensorless field oriented control for induction motors using the Kalman Filter. First the theory of field oriented methodology, with and without speed sensor, is described. Then a simulation approach is given for both cases. Finally the real-time implementation issues of a sensorless control are discussed. The paper presents an evaluation of the results. The processing capability of the processor is used to 50% at the current cycle times, the memory requirement is approximately 6823 Word program, and 2564 Word data space, of which 1024 Words are C-stack. The appendix contains full source code of the sensorless control for the TMS320C50 DSP, which is source compatible to the other members of the Fixed-Point DSP family like 'C1x, 'C2xx.