A clearing method for cascade hydropower spot market considering coupling relations of hydraulic power, electric power and electricity price

The traditional economic clearing method only considers the coupling relations of electric power and electricity price (EE), it is so called EE method in this paper. The contradiction between water abandonment and water shortage often arises in the clearing results of EE method. In order to address the contradiction, this study proposes a new spot market clearing framework suitable for series-parallel hybrid cascade hydropower stations where the coupling relations of hydraulic power, electric power and electricity price (HEE) are all taken into consideration. This framework presents a new index called hydraulic power-electric power (HE) coupling degree for assessing water abandonment and water shortage in cascade hydropower. Additionally, it suggests adjusting strategies to achieve optimal matching of hydraulic power and electric power. Lastly, a third-stage HEE deep coupling clearing model is proposed. The simulation results demonstrate several advantages of the proposed clearing framework over the traditional EE method. It not only ensures the economy of power purchase but also reduces water abandonment rate by 1.07 % and enhances the HE coupling degree by 3.41 %. Moreover, it effectively eliminates power shortage occurrences, achieves electric equilibrium of supply and demand in the power grid, and maximizes the utilization of abandoned water resources.