HDL Coder-based FPGA implementation of a continuous-discrete time observer for sensorless induction machine

A continuous-discrete time high gain observer (CDHGO) for sensorless control of an induction machine (IM) is proposed in this paper. From only the two undersampled and noisy stator current measurements, an estimation of the IM states variables such as rotor flux, mechanical speed, and the load torque is achieved. Precisely, After a mild change of state coordinates that transform the IM model into the quasi-block triangular form, both observation stages are designed in a cascade structure. A hardware implementation of the CDHGO is carried out in the FPGA target by using advanced Matlab tools namely HDL Coder and Fixed Point Designer. Through the ModelSim software, a validation of the implemented algorithm is performed, where the estimates brings closer the those provided by the model despite the lack of information between the sample instants and the presence of the measurements noise.

Automated summary

This paper proposes a continuous-discrete time high gain observer for sensorless control of an induction machine. The observer achieves an estimation of the machine's state variables using only two undersampled and noisy stator current measurements. The observer is implemented in hardware and validated using advanced Matlab tools.