A simplified model of quadratic cost function for thermal generators

Abstract

The paper describes practical method for analyzing the economic dispatch of a power system using Lagrange multiplier method regarding Kuhn-Tucker conditions, without taking into consideration the transmission limitations and losses. The example describes nine thermal generators with different fuel cost functions. Generator curves are represented with quadratic fuel cost functions and with simplified, linear model. Optimal solution of power output from each generator is presented, regarding both cost functions in correlation to different values of load demand. The possibility of using described simplified cost functions in active distribution network is also suggested.