A 3-leg VSC based integrated voltage and frequency controller for a self excited induction generator employing water pumping

This paper deals with an integrated voltage and frequency controller (IVFC) for a self excited induction generator (SEIG) in a standalone micro hydro system. The proposed IVFC is used to control the terminal voltage as well as frequency of SEIG system. This IVFC consists of a 3-phase 3-leg current controlled voltage source converter (CC-VSC) and its control scheme is realized using power balance theory (PBT). It regulates the terminal voltage through reactive power control and at the DC link of CC-VSC, a variable frequency vector controlled induction motor drive (VCIMD) driving a water pump is connected which maintains constant power generation at the SEIG terminals.