A new approach for synchronous generator terminal voltage control – Comparison with a standard industrial controller

This paper deals with the design and evaluation of a single input single output H∞ voltage controller. The proposed approach is based on optimizing the system modeling in order to obtain a robust and high performance controller. The adopted methodology is realized in five steps: (1) modeling of the exciter machine, the main synchronous generator, and the rotating diode bridge; (2) linearization of the excitation system; (3) using of a fictitious three-phase capacitor to represent the variable synchronous generator load as exogenous input of the system; (4) linearization of the feedback control by using a SISO (single input/single output) controller; (5) application of H∞ control method associated with weighting functions.The performance of the controller has been evaluated by experimental tests under different operating points of the synchronous generator. In addition, the comparison with a standard industrial controller will allow us to highlight the efficiency of the proposed design approach.

Research highlights► Modeling of the excitation structure and the SG with unknown load. ► Linearization of the excitation system. ► Design of H∞ voltage controller. ► Comparison with an industrial controller using experimental tests..