The DC bus voltage will fluctuate after the disturbance of the new energy output and load change of photovoltaics, energy storage, direct current and flexibility (PEDF), which poses a challenge to the stable operation of the DC air conditioning motor. The topology, advantages and disadvantages of DC air conditioning drive system and AC air conditioning drive system are analyzed, and the control strategy combining sliding-mode observer, maximum torque per ampere and leading angle flux weakening is researched, which can quickly adjust the control parameters of the motor by identifying the fluctuation of DC bus voltage. The simulation model of airconditioning motor using the above control strategy is built in Matlab/Simulink software, and the simulation verification is carried out according to the actual operation conditions of the air-conditioning. The results show that the control strategy can realize the stable operation of the air-conditioning motor in the full speed range under the DC bus voltage fluctuation.