Evaluation of voltage control speed of the synchronous generator - UPFC units in power distribution schemes of power plants

The main method of voltage and reactive power control is to change the excitation current of synchronous generators. This method requires a complex excitation system that can provide a necessary control range. In addition, response performance of such control is constrained by a long time constant of the excitation circuit. One of the alternative control methods is the use of power units including synchronous generators with a non-controlled excitation system and unified power flow controllers (UPFC). The MATLAB Simulink software package enabled research of mode control performance of such power units and comparison with the thyristor excitation systems. Furthermore, a real voltage change was analyzed at short-circuit in the power system. The synchronous generator - UPFC power units are proved to implement a high-speed voltage control, which can significantly increase flexibility and adaptability of mode control in the power distribution circuits of the power plants.