DISCRETE-TIME MODEL REFERENCE ADAPTIVE REGULATION OF NODAL VOLTAGE AMPLITUDE IN POWER SYSTEMS

This paper deals with the problem to regulate the nodal voltage amplitude in electrical power systems. A discrete-time linear model that embeds an unknown bias representing the no-load voltage is adopted to describe the power system dynamics. Due to the unpredictable and unknown variations of the power system normal operating points the model parameters are unknown and time-varying. To ensure that the controller exhibits the required performance even in presence of a such variations, the controller parameters are varied according to adaptive laws. These laws are developed on the basis of a gradient approach to minimize the squared augmented error. The properties of the designed adaptive laws are studied employing Lyapunov analysis. The results of numerical simulation are reported to validate the proposed design.