Decentralized load frequency control method by means of frequency measurement of adjacent power systems

The presently used TBC and FFC methods have satisfactorily maintained power system frequency within a prescribed tolerance. With steady increase in power system capacity, however, undue fluctuations in tie-line power flow has become prominent. This fact suggests the shear necessity of establishing a more sophisticated LFC system. Intensive research efforts have been concentrated on applications of modern control theory, above all linear optimal control (LOC) using the state regulator theory. This paper presents a decentralized suboptimal LFC method which makes use of the frequencies of adjacent areas in addition to local information to calculate the control variables of each area. This artifice has made it possible to realize a practical yet almost optimal control scheme. Simulation studies on a 4 area system have demonstrated the effectiveness of the proposed method.