Multivariable model reference adaptive control for a three-phase uninterruptible power supply

Weakly coupled multivariable control systems have been focused on through decentralized adaptive control techniques by considering couplings as unmodeled dynamics. Transient response may become unacceptable when coupling is significant. The paper presents a multivariable indirect model reference adaptive controller for three-phase uninterruptible power supplies. A reduced model with two inputs and two outputs, through αβ0 transformation is used. A minimum variance control law is used to ensure performance. Simulation results show the potentialities of this technique, although care must be taken to avoid singularities in the control law