Hydro power plants operating modes in a cascade system depending on the needs of the power system

The paper presents the methodology for hydro power plants operation (Long-term and Short-term) in a hydro power cascade system. It includes water managing of generating and/or pumping units taking into accounts technical characteristics of the power plants facilities (turbine/generator and pump/motor systems), reservoirs characteristics considering all hydraulically connected infrastructures which are, as well as the hydrological conditions (for run offs and turbine inflows). The goal of the operation for all hydropower system is to have maximum profit from electricity production taking into account electricity market environment, power system requirements, as well as satisfying technical conditions and at the same time avoiding water spilling as it is maximum possible. Operating modes of the hydro power plants depend on electricity market price, tariff prices and time duration of each tariff (base, peak, and rush hour), technical characteristics of the unit(s), hydro technical conditions, water reservoir’s volumes, run off and others. The application of the model is presented with the results on real hydro power systems consist of different hydraulic connections in various cases depend on hydrological conditions and requirements. The model can be used to make preliminary analysis for additional improvement of hydro systems as having the results for additional installed power of the existing system. The selected output results are presented with appropriated comparing and at the end with conclusion remarks.