Method and device for controlling re-electrification of air conditioner after power failure and air conditioner

The invention provides a re-electrification control method and device for an air conditioner after power failure and the air conditioner. The method comprises the steps that in a specified time period, if the air conditioner is powered on again after being powered off, and a remote controller instruction is still not received when the power-on duration reaches a preset first duration, the air conditioner is controlled to enter a simple refrigeration mode; in the simple refrigeration mode, an indoor unit of the air conditioner is controlled to operate in an air supply mode, and an air guide door of the indoor unit is controlled to circularly rotate according to a preset rotation mode until the air supply operation duration reaches a preset second duration; and the air conditioner is controlled to be switched into a dehumidification mode for operation until the dehumidification operation duration reaches a preset third duration, the indoor environment temperature at the moment is obtained, a target operation mo