A Feedback Linearization Scheme for the Control of Synchronous Generators

This paper proposes an advanced nonlinear control algorithm to manage active power and voltage provided by a synchronous generator. The algorithm is based on the so-called FeedBack Linearization (FBL) theory, which relies on the central concept to algebraically transform nonlinear systems dynamics into fully or partly linear ones, so that linear control techniques can be applied. Starting from the basic (electrical, magnetic and mechanical) machine equations, a suitable state transformation is introduced in order to apply the FBL block to the generator model. A regulation scheme is then derived, which receives as input the measure and the reference signals of both the electric power and the voltage at the generator side and produces as outputs the physical inputs of the machine, i.e. the mechanical torque and the field voltage. Particular attention is devoted both to the linearization process, where internal dynamics and stability studies play an important role, and to the design of the two (Power and Voltage) decoupled regulators. Several simulations are finally performed in order to verify the effectiveness of the proposed approach and to highlight its main advantages and drawbacks with respect to the traditional P-V synchronous generator control strategy.