Power conditioning system of Flywheel Energy Storage

In a Flywheel Energy Storage system (FESS), the power conditioning system is the key component of controlling power transfer between the Flywheel and the power system. The dynamics of the power conditioning system directly affect the effect of FESS in dynamic regulation of power system. In this paper, power conditioning system which is made up of a doubly-fed induction machine (DFIM) connected with flywheel, a back to-back converter for AC excitation and an excitation vector control system is studied. The excitation control strategy is presented for FESS DFIM to improve transient stability and increase transfer capability of power systems. The proposed control method has good dynamics that can respond to the system power demand quickly and accurately. Moreover, the proposed control method has good robust characteristic and applicability to improve the performance of power conditioning system. Simulation and experiment results are performed to evaluate the performance of the proposed control method.