Observer-Based Output Voltage Control for DC Power Distribution Purposes

Observer-based output voltage control is proposed for single-phase full-bridge inverter, that is used to produce the voltage for a customer in a low-voltage direct current distribution network. To avoid difficulties to realize a feasible-output-voltage-tracking control for sinusoidal references, the control system is realized in a virtual dq-frame. The virtual frame is created using a second-order generalized integrator. In the proposed control system, two different observer structures are applied. Using observer-based control, also provides means to reduce the number of measurements down to one. In this paper, different realizations of an estimator-based control system for a single-phase inverter are investigated. Specifically, it is considered how many measurements are needed and which variables should be measured and which estimator structure is to be applied in order to achieve the best overall performance.