IMPROVEMENT OF DYNAMIC STABILITY IN A MULTIMACHINE POWER-SYSTEM VIA SMES WITH ACTIVE POWER MODULATION CONTROLLED BY FREQUENCY DEVIATION

With the recent increase in demand, power systems have become large and complex and generation plants are located far from the load center. As a result, power system instability has become more serious. On the other hand, the active and reactive powers are controlled rapidly and flexibly by the superconducting magnetic energy storage (SMES) system. This paper proposes a practical method to suppress power oscillation in a multimachine power system by using SMES wherein its active power is controlled by the signal derived from a bus frequency deviation. This controlled scheme is conducted easily only by detecting the frequency deviation on the site. The proposed method is examined on a 4-machine miniature power system connecting a 1-MJ SMES as well as another digital simulation using the same model. The effectiveness of the proposed method is shown.