Abstract
A Rotary Phase Shifter (RPS) is proposed to maintain power schedule across tie-lines in interconnected power systems. Power flow can vary widely from the scheduled power due to the unbalance between generation and load that causes frequency fluctuations in interconnected power systems. The Rotary Phase Shifter which is basically a wound rotor induction machine can be placed between two interconnected power systems to control the power flowing from a non-utility-owned generation (NUG) to a large utility. The primary objective would be to maintain the power schedule across the interconnection by controlling the torque on the rotary phase shifter. A model of the RPS and a control strategy for it are presented. Experimental studies on a reduced scale two-area power system show that following a local disturbance, the rotary phase shifter allows the desired setting of tie-line flows regardless. of load conditions and the system as a whole operates in an optimal fashion.
