A physically insightful approach to the design and accuracy assessment of flux observers for field oriented induction machine drives

ANN Based Flux and Torque Estimator for Vector Controlled Induction Drive with Dynamic Loading

“…In the proposed scheme, the parameter sensitivity would not greatly plague the accuracy of the measurement and calculation of flux, torque and field angle. A partial operating frequency dependent hybrid flux estimator for stator resistance tuning [16] has problems of convergence and slow response, thereby necessitating the use of intelligent control technique such as Neural Networks and Fuzzy Logic.…”

Simulation of Induction Machine Drive by Composite Model Flux Observer

“…Due to the problems with VM at low speeds, the rotor flux is here preferably estimated using the current model, while the voltage model is suitable at higher speeds, see e.g. [6], [7] and [8]. By combining CM and VM what is called Composite Model flux observer we tried to illustrate advantages of each individual at low and high speed performance using simulation in Matlab/Simulink.…”

Dynamic analysis of current regulators for AC motors using complex vectors

“…Although the dynamic analysis of the different flux observer designs is beyond the scope of this paper [10], [11], a brief study for the case of a current-model-based flux observer is presented.…”

“…14 shows a simulation of a rated -axis-current step with a rotor speed equal to three times the rated speed, infinite inertia, and a 10% underestimation in the flux observer inductance. The axis is aligned with the estimated rotor flux at 90 according to (10). Fast current regulators will keep the estimated rotor flux magnitude constant and equal to the commanded value, but variations both in the magnitude and the phase of the actual flux are observed.…”

“…When scalar instead of complex vector notation is used, the transformation of a generic complex vector quantity from complex vector to scalar notation can be done by taking real and imaginary parts after substituting as shown in [3] (9) Applying (9) to (5), and assuming (as commonly done for rotor flux field orientation) that the synchronous frame has been aligned with the rotor flux (10) the equivalent scalar nonlinear state equations (11) and (12) corresponding to the complex vector equation (5) are obtained (11) (12) Different representations of the induction motor are often used [3], [5], depending on how the quantities are rearranged. If, for example, the flux state equation (6) is solved with the current state equation (5), the rotor speed variable can be eliminated with the result, as shown in…”