Speed sensorless induction motor drive with predictive current controller

Today, speed sensorless modes of operation are becoming standard solutions in the area of electric drives. This paper presents a speed sensorless control system of an induction motor with a predictive current controller. A closed-loop estimation system with robustness against motor parameter variation is used for the control approach. The proposed algorithm has been implemented using field-programmable gate arrays (FPGAs) and a floating-point digital signal processor (DSP). Both computational elements have been integrated on a single board SH65L type and interfaced to the power electronic converter, and the use of proper FPGA and DSP optimizes the cost and computational properties. The novelty of the presented solution is the integration of a simple observer for both speed/flux and current control purposes, and the obtained results have been improved in comparison to the previous works. An overview of the test bench consisting of a digital control board, as well as computational algorithms and system benchmarks, is presented. All the tests were performed experimentally for 5.5-kW electric drives.