Influence of the Winter Factor on the Daily and Mean-Multiyear Power Factors of HPP

Power factors of HPP are defined more precisely for greater detail when considering operation under winter conditions. The relationship between the levels and flow rates of water in the lower pool of hydroelectric power plants exerts a significant influence on the rated power and generation of electric power at HPP. The indicated relationship is well- defined only for uniform water movement. Factors for which this movement becomes non-uniform, and the curve of the relation between flow rates and levels ambiguous exist, however, under natural conditions involving management of daily flow regulation. One of these factors is non-steady movement of water as ice forms in the fall-winter period. Ice formation leads to variation in the free-cross-sec- tional area of the river channel, an increase in roughness, and, as a consequence, to a reduction in its carrying capacity. The relationship between the flow rates of water in the win-