Implementation of direct torque control of induction machine utilising TMS320C31 digital signal processor

Abstract

Digital signal processors (DSPs) are becoming more popular in the area of AC motor control, in particular the induction motor drives. The fast number crunching capabilities of DSPs which are traditionally meant for data processing tasks such as image processing and speech recognition, are being utilised to perform on-line calculation of the AC motor variables, such as electromagnetic torque, fluxes, mechanical speed, etc. This paper presents the implementation of a high performance induction motor control technique known as direct torque control (DTC) utilising the TMS320C31 DSP from Texas Instrument. To minimise the sampling period of the implemented drive system, a Xilinx FPGA (XC4005E) is used to perform some of the main tasks of DTC drives. Experimental results of this high performance drive system on a 1/4 hp standard induction motor are as expected and agree with the theoretical work.