Cabin inlet air preheating and heat preservation system of polar region long-term operation ship

The invention relates to a cabin inlet air preheating and heat preservation system of a polar region long-term operation ship, and relates to the field of ships, the cabin inlet air preheating and heat preservation system comprises an inlet air heating system, a cabin heat preservation system and a direct inlet air heating system, the tail end of the inlet air heating system is connected to the cabin heat preservation system, and the cabin heat preservation system is connected with the direct inlet air heating system; fresh air entering the cabin utilizes heat dissipation of existing equipment through the cabin heat preservation system, ventilation and temperature adjustment in the cabin are achieved at the same time, and the air volume of the cabin fresh air needing to be preheated by the air inlet heating system is reduced. The combustion air volume of main power equipment is obtained from the outboard through the direct air inlet heating system, and meanwhile the engine room heat preservation system provid