OPTIMAL ECONOMIC OPERATION OF THERMAL AND VARIABLE HEAD HYDRO SYSTEMS USING HAMILTON-LAMONT'S MODEL AND NEWTON-RAPHSON METHOD

ABSTRACT

In this paper, optimum scheduling of an integrated hydro-thermal electric power systems with variable head hydro plants, is treated. The scheduling problem is solved by the use of coordination equations developed by Ricard and Kron. There are many reported models to represent the performance of a hydro plant, and here Hamilton-Lamont's model is used to derive specific optimality conditions for the problem. Using Newton-Raphson method, an algorithm is developed for solving iteratively the problem of optimal power scheduling. The iterative method is implemented using a specially designed initial guess estimator based on the physical properties of the problem to generate a set of feasible initial estimates of the unknowns to speed up the process. A number of example systems are used to test the performance of the algorithm. Successful convergence of the algorithm is reported in this paper and results for one sample test system are given.