All fresh air direct expansion type unit based on electronic expansion valve

According to the all fresh air direct expansion type unit based on the electronic expansion valve, a refrigerant is transmitted through a circulating pipe network between an indoor unit and an outdoor unit, and indoor temperature adjustment is achieved through liquefaction heat release of the refrigerant in the outdoor unit and vaporization heat absorption of the refrigerant in the indoor unit. In the process that the refrigerant moves from the outdoor unit to the indoor unit, the electronic expansion valve completely responds to the actual opening degree requirement of the unit during operation, and the unit can give full play to the performance of the maximum vaporized refrigerant in most of the time. Specifically, the electronic expansion valve adjusts the opening degree of the electronic expansion valve according to the comparison of the actual suction superheat degree and the target superheat degree, so that the electronic expansion valve is rapidly adjusted to the optimal opening degree value, and effic