| Abstract |
Application of decoupling circuits is mandatory, if a high performance induction motor drive with field orientation along stator or airgap flux is to be realized. Decoupler equations are derived from constant parameter induction machine model. However, actual machine parameters are subject to variation. As a consequence, deterioration of drive performance from expected may occur. One of the sources of parameter variations is the main flux saturation. This paper discusses effects of main flux saturation on behavior of a vector controlled, current-fed, induction machine with orientation along stator and airgap flux. Constant parameter decouplers are employed in conjunction with appropriate model of saturated induction machine and simulation study is carried out for a number of different operating conditions. At first, it is assumed that the value of the magnetizing inductance in the decoupler is set to correct value which corresponds to rated operating point. The second part of the simulation study deals with effects of application of detuned magnetizing inductance value in decoupler equations. It is shown that orientation along stator flux exhibits higher degree of sensitivity to saturation level change in the machine, compared to airgap flux orientation. |
