Study On Hydropower Station Operation At The Low Water Level

With the advance of the national electricity price reform, the rainy and dry season power price gradually implemented throughout the country. Electricity pricing policy, low in ranny season and high in dry season, has been taken the lead to implement in Sichuan Province. It raised new issues to the economic operation of hydropower stations. Ertan Hydropower Station is an example in this paper, the safe operation and benefit influence of power plant are studied when reducing dead storage level to increase storage capacity and further playing a regulating role of reservoir. New ideas of economic operation are proposed for hydropower stations having the capacity of seasonal regulation.Aiming at the hydrology and runoff characters of Ertan hydropower station, finite difference method as sub-period and reach are adopted. The digital simulation system software (SUSBED-2) on river reservoir sediment can calculate the sediment flushing based on the three primary levels of dead water schemes. The results show that there are no undesirable effects for the sediment flushing of reservoir when reducing the level of dead water; on the contrary, it can delay the sedimentation of reservoir.Based on the arch data about building and operation, using arch-cantilever method, we analyze the affect to dam structure security on low water-level operation and find out the main load factors. By regression analysis, the contact state among seam surface has been predicted.Study on the operation condition of hydraulic turbine, get the probably lowest water head suitable for the turbine operation, and analyze the energy index on the low head, cavitations characteristics and operation stability. According to the site test data, some operation trend analysis and operation suggestions have been put forward.According to the runoff series, the storage curve, the operation chart, and the drafted plan on death water level, calculate the flow regulation and the energy index, analyze the unit blocked capacity, the effective electric quantity and the electricity generation income. A result that low water-level operation under tou power price policy is beneficial to improve the generation benefit of hydropower station has been educed.