Sensorless vector control of induction motor based on flux and speed estimation

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2008
Ertuğrul, Barış Tuğrul
The main focus of the study is the implementation of techniques regarding flux estimation and rotor speed estimation by the use of sensorless closed-loop observers. Within this framework, the information about the mathematical representation of the induction motor, pulse width modulation technique and flux oriented vector control techniques together with speed adaptive flux estimation a kind of sensorless closed loop estimation technique- and Kalman filters is given. With the comparison of sensorless closed-loop speed estimation techniques, it has been attempted to identify their superiority and inferiority to each other by the use of simulation models and real-time experiments. In the experiments, the performance of the techniques developed and used in the thesis has been examined under extensively changing speed and load conditions. The real-time experiments have been carried out by the use of TI TMS320F2812 digital signal processor, XILINX XCS2S150E Field Programmable Gate Array (FPGA), control card and the motor drive card Furthermore, Matlab “Embedded Target for the TI C2000 DSP” and “Code Composer Studio” software tools have been used. The simulations and experiments conducted in the study have illustrated that it is possible to increase the performance at low speeds at the expense of increased computational burden on the processor. However, in order to control the motor at zero speed, high frequency signal implementation should be used as well as a different electronic hardware.

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Citation Formats
B. T. Ertuğrul, “Sensorless vector control of induction motor based on flux and speed estimation,” M.S. - Master of Science, Middle East Technical University, 2008.