Abstract: In order to facilitate the coordinated development of pumped storage hydropower (PSH), planing the scale and timing of thermal power retirement, promoting the integration of wind and solar power, ensuring the stable and low-carbon transition of the power system. An exploration into the multifaceted and multilevel comprehensive benefits within the power system transformation is conducted. Taking the power system transformation program of Xinjiang Uygur Autonomous Region as an example, a power system simulation model is built with detailed consideration of the operational characteristics of PSH and thermal power. The numerical simulation formulated two categories for the Xinjiang power grid (internal demand model and internal demand + external transmission model), corresponding to six transformation scenario models. Each scenario combined with Analytic Hierarchy Process (AHP) and Entropy Weight Method, in order to establish a comprehensive evaluation index system for economic and technical aspects. The results indicated that the current scale of PSH are unable meet the future demands of Xinjiang power grid for orderly thermal power decommissioning and high percentage of renewable energy power abandoning rate. The coal consumption would be generated regardless of the capacity of thermal power participating in peak-regulation. In summary, the reasonable demand scale of PSH for the Xinjiang power grid (internal demand only) is between 10 million kW and 15 million kW, and and for the Xinjiang power grid (internal demand + external transmission) is between 15 million kW and 20 million kW in 2030. The research can provide a theoretical support for the construction of a new-type power system, the orderly development of PSH commissioning and thermal power decommissioning, and the integration of wind and solar power.