Linear parameter varying controller for an induction machine

Field-oriented controllers for induction machines decouple control of torque and flux. Such inverse-based controllers may however show poor robust performance in presence of independent input uncertainty. To overcome this problem, the possibility to design a linear parameter varying controller based on H_∞ theory is examined. The controller is adapted to a varying stator frequency and apart from estimating torque and stator flux magnitude, the robust design embodies the entire control law. The controller calculates the stator voltages from torque and flux control errors only. Saturation of the stator voltage amplitudes for higher stator frequencies is also considered.