Transient response of pico-hydro power generation system with automatic excitation units under fault conditions

It is important to improve voltage stability of hybrid generation system based on renewable energies by using automatic excitation units in pico-hydro generation system. Based on the mathematical model, an equivalent dynamic model of a pico-hydro power generation system including hydro turbine, synchronous generator, automatic excitation system was created in ElectroMagnetic Transient Program/Alternative Transient Program (EMTP/ATP) software package. Case study was carried out to investigate the operational characteristics of pico-hydro system under fault conditions in a micro grid. Simulation results showed that the automatic excitation regulation and control system could improve the voltage stability by increasing excitation current rapidly as low voltage occurs during fault conditions.