Mathematical models of inter-plant economical operation of a cascade hydropower system in electricity market

Regional operation of the electricity market has begun in China. With the development of China's market economy, hydropower will enter the arena of bidding for connection to the grid in light of ‘fair, impartial and open’ principles. For the electricity market, the solution of an inter-plant economical operation of a cascade hydropower system is extremely important. If a hydropower company is incapable of predicting the generation capability and the amount of generation of hydropower stations as well as the risk-rate corresponding to various generation amounts, then there is no information available to the hydropower company to refer to when it makes future agreements in a certain period. This paper develops mathematical models of (1) total minimum stored energy consumption and (2) total minimum water consumption for a cascade hydropower system. The models provide a solution to the problem of rational distribution of next-day's generating schedule in a cascade hydropower system awarded a contract in the bidding for connection to the grid. A case study is conducted to verify the effectiveness and applicability of the methodology.