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

• The contribution of a pumped-storage plant to the load-frequency control is analyzed.
• The pumped-storage plant is a hydraulic short-circuit scheme.
• A simulation model has been developed that considers the AGC of the power system.
• The response of the units to frequency deviations and AGC signals has been modeled.
• Different participation factors of the synchronized units have been considered.

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 electromechanical 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.