Improving power quality with a variable speed synchronous condenser

This paper explores the use of a wound rotor doubly fed induction machine (DFIM) as a controlled active and reactive power compensator, for voltage control in a power system as well as load-leveling device, combining the characteristics of a synchronous condenser and those of a low speed flywheel generator. Firstly an analytical model of the DFIM is presented, which is used to demonstrate how the power factor of the stator winding can be controlled with the converter. This analysis is confirmed with simulations. Secondly, a vector control scheme is presented which de-couples the reactive and active power control. This control is validated with SABER simulations.