Advanced Load Frequency Control

The problem of designing a load frequency control law which reduces transient frequency oscillations (swings) and reduces the number of control signals sent to power houses is investigated. A linear model of an area of an interconnected power system is developed, and a discrete time, linear-plus-deadband, feedback control law is designed. Feedback variables include cumulative inadvertent interchange, frequency deviation, integral of frequency deviation, real power absorbed by loads, and governor-turbine variables. This linear-plus-deadband control is an application of a special case of a more general "set-theoretic" class of control laws. A simulation of two areas with two hydro sources is presented. The dynamic response to a step load change is determined for the case of no load frequency control, load frequency control presently used by power companies, and load frequency control designed in this paper.