Economical Evaluation on Flexible Transformation of Variable Speed Pumping Storage Considering Electricity Price Mechanism

As a mature technology for energy storage, pumped storage is an efficient technology to solve the problem of new energy consumption. Limited by different regional conditions, the traditional constant speed pumped storage has highlighted the problems of poor head adaptability and insufficient flexible adjustment ability in application, which makes variable speed pumping and storage units the best choice for future pumping and storage power stations. However, how to evaluate the economic efficiency of variable speed transformation schemes is a difficult problem to be solved urgently. This paper considers the effect of the current electricity price mechanism in the spot market on the retrograde income, and uses the Analytic Hierarchy Process, AHP) -Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS), an economic evaluation method for variable speed pumping and storage transformation is presented. Economic evaluation indicator system for variable speed pumping and storing transformation is established from four aspects: financial benefit, technical and economic benefit, social benefit and extra benefit. The weight method of AHP is improved, and combined with TOPSIS, the economy of variable speed pumped storage transformation project is scored, and the economic benefit after transformation is obtained. Finally, three variable-speed pumped storage power plants at Jiangshantou, Qidutan and Shuixiakeng are analyzed with numerical examples, and then the effectiveness and feasibility of this approach were tested.