Optimizing the operating schedules of hydroelectric stations in power systems

Abstract

Optimization of long-range schedules for the utilization of water resources should be conducted primarily on the basis of the criterion of minimal economic outlays for the overall power-water storage complex. Each hydraulic generating unit and large-scale network of hydraulic generating units in particular are intricate water-storage complexes, which attract the interest of many branches of the national economy: power engineering, water trailsport, the fishing industry, the agricultural indus~y, water supply, logging, etc. The interrelation between the heavily conflicting Luterests of all water users and consumers in the complex is an extremely intricate problem. since there are virtually no approved methods of scientifically founded economic evaluation of the loses due to water deficiencies for any of the branches of the national economy. At the present time, therefore, the demands of each participant in the complex are normalized and determined in the plan for design provision established for each water user. Consideration of the interests of all participants in the water-storage complex is mandatory for optimization of the power schedules governing operation of the hydroelectric stations, and is given in the form of different kinds of restrictions. Meeting the demands of nonenergy water users occasionally imposes restrictions so rigid that optimization becomes virtually impossible from the standpoint of power schedules. For example, the schedules of the Syrdar'ya network is completely subordinate to irrigation demands for the sowing of cotton and rice in low-water years. In the computer-design programs used in practice, the problem of optimizing the long-range operating schedules of hydroelectric stations reduces, as a rule, to a design based on some of the following power criteria: a) a minimum outlay of fuel burned at the thermal electric stations in the power systems; b) minimum ideal-fuel consumption at the thermal electric stations and c) maximum generation of electricity at the hydroelectric stations. In conformity with the operating practice that has been established, different program variants are employed to solve different problems. Optimization of the long-range operating schedule of the hydroelectric stations of the Angara-Enisei network is carried out by the Siberian Integrated Dispatching Con~oi in accordance with a program developed the Siberian Power Institute of the S~erlan Department of the Academy of Sciences USSIL in conjunction with the Siberian Integrated Dispatching Control. The program utilizes the criteria of minimum energy-fuel consumption at the ther