Disturbance Observer-Based Feedback Linearization Control for Three-Phase Power Inverters in Autonomous Mode of Operation

This paper presents a disturbance observer-based control (DOBC) for three-phase inverters operating in autonomous mode. The controller design targets the regulation of the output voltage during transient conditions induced by internal uncertainties and external influences. The controller scheme combines Feedback Linearized (FL) controller with a Disturbance Observer (DO) to achieve dual objectives of disturbance attenuation and integral control action. The performance of the above controller is tested via simulation for scenarios such as abrupt load variations and parametric uncertainties. The test results have demonstrated excellent disturbance attenuation to achieve desired transient response under the tested scenarios. Furthermore, its performance when supplying non-linear loads is assessed. The controllercan produce a sinusoidal output voltage with reduced THD that complies with IEC62040 standards.