LQI-Type Load-Frequency Control for Multi-Area Electric Energy Systems

This paper presents a new method of designing discrete-type load-frequency regulator for interconnected power systems. Discrete-type optimal control law is decided by defining a discrete-type quadratic performance index and then minimizing it in accordance with the dynamic programming approach. An especially attractive feature of the proposed control scheme is that it requires as inputs signals accumulative quantities of area control error. The realization of such a regulator may be easy and of low cost because of its simple costruction. In this paper, we apply the above method to 3～5-area systems provided with nonreheat type turbines. The results show that the proposed discrete-type regulator can act satisfactorily for improving dynamic responses of the load-frequency cotrol