Switched control of frequency of interconnected power systems using variable structure†

This paper proposes a new technique based on eigenvalue assignment for the design of a variable structure load frequency controller for interconnected power systems. An important feature of the variable structure controller is that it can effectively improve the transient performance of the system while at the same time ensuring zero steady-state error. Further, when the variable structure system is operated in the so-called sliding mode, the response of the system becomes insensitive to plant parameter variations. The control problem is formulated and the results of a digital simulation study are presented for illustration. For comparison purposes, results obtained using a conventional integral controller and a linear optimal controller are also included.