Multivariable load current sensorless controller for universal active power filter

The universal active power filter is one of most efficient solutions to problems related to energy quality. The topology integrates series and parallel active filter, and theoretically has the compensation capacity of both. The efficiency of compensation, however, is dependent on the control strategy implemented. Moreover, the controller determines the necessary number of sensors and measurement techniques, consequently, it determines associated costs. This study uses a multivariable approach for synthesis and development of a decoupled control. The proposed strategy uses only measuring of the input currents, thereby reducing the number of current sensors. The strategy is validated in simulation and experimentally in a 1.1 kVA laboratory prototype.