Coordinated Stabilizing Control for Large Scale Interconnected Power System by Superconducting Magnetic Energy Storage Unit and Power System Stabilizers

Abstract

The intension of large scale power system interconnection is to achieve extremely economical and reliable power generation and transmission. It has established the present power systems of high quality. On the other hand, in the large power systems with complex configuration, undamped power swing with low frequency caused by the synchronous power between interconnected systems tends to occur as well as undamped power swing caused by the synchronous power of specific generators. Several coordinated stabilizing control schemes for the power systems by sets of power system stabilizers (PSS's) have been investigated so far. PSS is very effective for the stabilization of power swing among a few specific generators because the function of PSS is achieved by the voltage control using the generator field winding circuit. However, it seems that PSS do not have sufficient ability to stabilize the power swings between interconnected systems. In this paper, the superconducting magnetic energy storage (SMES) which is significantly effective for the power swings between interconnected systems, is introduced and a coordinated power system stabilizing control by SMES and PSS's is proposed. The advantages of the proposed control scheme are: 1. high efficiency of the controller by the distribution of functions, 2. independency of the control design for PSS and SMES, 3. robustness of the controller and so on.