ON-LINE GRASP OF LOAD SYSTEM CONDITIONS WITH DISTRIBUTED GENERATORS BY USE OF SMES

According to the deregulation in electric power industries in recent years, it becomes important to grasp operating conditions of the load system side from on-line data and to evaluate dynamic characteristics of the load system (distribution system). In this paper, we propose to estimate the load system state including distributed generators (DGs) from on-line data by use of a superconducting magnetic energy storage (SMES) system. Basic experiments were carried out on an analogue-type power system simulator and a model SMES for simulator. The SMES gives a small power modulation to the power system of known pattern. Power system responses are analyzed to obtain the eigen-values of the system and transfer function between distribution line power and SMES's power disturbance, for example, using a spectral analysis and a model identification method. Dynamic characteristics of the load system including distributed rotating generators are estimated. The availability of the proposed method is discussed by the experimental results.