Abstract: A power angle control method for DC system with doubly-fed induction generator based on air gap

flux vector regulation was presented，which could reveal the relationship between the air gap EMF vector angle and

the stator output power，and could be used to directly control the stator output power. In the proposed method，the stator frequency was determined by the speed of the air gap flux vector，and the output power was determined by the angle of the air gap electromagnetic field vector，the stator frequency could be generated through the power control loop，which could avoid the problem of DC sampling deviation of the traditional voltage model and current model and reduce the dependence of parameters. Since the product of the stator frequency and the d-axis rotor current was constant，the stator frequency could be adjusted by the d-axis rotor current. In addition，since the airgap flux was oriented by the q-axis airgap flux control to zero，the improved control method of direct resonance control torque ripple and harmonic current mitigation could still be applied to this control method. Finally，the effectiveness of the proposed control method was verified by experiments.

    Key words: air gap flux vector； direct resonant control； doubly fed induction generator（DFIG）；power

angle control