Dynamic Droop-Based Inertial Control of a Doubly-Fed Induction Generator

作者：Hwang Min^*; Muljadi Eduard; Park Jung Wook; Sorensen Poul; Kang Yong Cheol

来源：IEEE Transactions on Sustainable Energy, 2016, 7(3): 924-933.

DOI：10.1109/TSTE.2015.2508792

• Dynamic droop
• frequency nadir
• inertial control
• rate of change of frequency
• wind turbine generator

If a large disturbance occurs in a power grid, two auxiliary loops for the inertial control of a wind turbine generator have been used: droop loop and rate of change of frequency (ROCOF) loop. Because their gains are fixed, difficulties arise in determining them suitable for all grid and wind conditions. This paper proposes a dynamic droop-based inertial control scheme of a doubly-fed induction generator (DFIG). The scheme aims to improve the frequency nadir (FN) and ensure stable operation of a DFIG. To achieve the first goal, the scheme uses a droop loop, but it dynamically changes its gain based on the ROCOF to release a large amount of kinetic energy during the initial stage of a disturbance. To do this, a shaping function that relates the droop to the ROCOF is used. To achieve the second goal, different shaping functions, which depend on rotor speeds, are used to give a large contribution in high wind conditions and prevent over-deceleration in low wind conditions during inertial control. The performance of the proposed scheme was investigated under various wind conditions using an EMTP-RV simulator. The results indicate that the scheme improves the FN and ensures stable operation of a DFIG.

• 出版日期2016-7