Method and device for obtaining temperature difference between supplied water and returned water of cooling water system, equipment and medium

The invention provides a supply and return water temperature difference obtaining method and device of a cooling water system, equipment and a medium, and belongs to the technical field of cooling water systems.A system energy efficiency model of the cooling water system is constructed, the cooling water system comprises a cooling water pump, a chilled water pump, a refrigerator, a cooling tower and a pipe network, and the operation mode of the cooling water system is obtained; if the operation mode is an optimized operation mode, obtaining a derivative of the system energy efficiency model to a target supply and return water temperature difference parameter, obtaining a supply and return water temperature difference obtaining model, calculating an extreme value of the supply and return water temperature difference obtaining model, and obtaining an extreme value of the supply and return water temperature difference obtaining model; the extreme value serves as the target supply and return water temperature dif