Research on excitation control of flexible power conditioner doubly fed induction machine

The multi-functional flexible power conditioner (FPC) can perform multi-functions including energy storage, active and reactive power generation, and considerably enhance power system stability and quality. The motor adopted in FPC is doubly-fed induction machine (DFIM with large rotating inertia. This paper firstly establishes the model of FPC DFIM. It proposes and analyses the five operation states such as energy storage, active power generation and reactive power generation, speed limitation and floating charge. It puts forward the excitation control strategy of the FPC DFIM with the combination of the power-mode control and speed-mode control. The FPC multi-functions are realized on an asynchronous motor of small capacity. The experimental results verify the excitation control strategy proposed and the good dynamic and static performance of the system while switching control mode under various operation states.