Multi-stage fine filter unit for circulating water

The invention discloses a multi-stage fine filter unit for circulating water, wherein the multi-stage fine filter unit comprises a box body; a full-flow filtration system, a bypass filtration system and an intelligent control system which are mounted on a main pipeline are arranged in the box body, the full-flow filtration system adopts an automatic inner brush type filter, and the bypass filtration system comprises a water pump, a bypass filter primary filter and a bypass filter secondary filter; the water inlet end of the water pump is connected with the main pipeline, the water outlet end of the water pump is connected with an inlet of the bypass filter primary filter, an outlet of the bypass filter primary filter is connected with an inlet of the bypass filter secondary filter, an outlet of the bypass filter secondary filter is connected with the main pipeline, and the intelligent control system is electrically connected with the full-flow filter system, the bypass filter primary filter and the bypass fil