Contribution of a hydraulic short-circuit pumped-storage power plant to the load-frequency regulation of an isolated power system

In this paper, the contribution of a hydraulic short-circuit pumped-storage power plant (HSCPSPP) to the load frequency regulation (LFR) of an isolated power system has been further analyzed by means of simulations. For this purpose, a simulation model has been developed that considers the AGC system and both the synchronized thermal units' and the HSCPSPP's response to frequency deviations and power set-point signals sent by the AGC system. The frequency deviation of the power system and the electro-mechanical behavior of the HSCPSPP have been modeled by using commonly accepted approaches for studies on long-term dynamics of power systems. The behavior of the penstock has been considered through an elastic water column model. The simulations results demonstrate that the HSCPSPP has a large flexibility and that can contribute to a great extent to the LFR of the system, while fulfilling the requirements established by the TSO and preserving the plant safety. (C) 2014 Elsevier Ltd. All rights reserved.