Aiming at the problems of insufficient frequency regulation space and low dynamic response of the power system caused by large-scale wind power access
this paper proposes a new frequency coordination control strategy. Firstly
under the load-shedding reserve operation mode of doubly fed induction generator (DFIG)
pitch angle control is enhanced by introducing droop control. When system frequency drops
the DFIG releases its load-shedding reserve power
thereby compensating for the active power dip during DFIG rotor speed recovery and reducing steady-state frequency deviation in the system. Secondly
by incorporating a mechanical power compensation stage to enhance virtual inertia control
the system releases part of the kinetic energy stored in the DFIG rotor to support dynamic frequency response. This boosts system inertia and reduces dynamic frequency deviation. Finally
a power system simulation model was built through Matlab/Simulink. The simulation results show that this strategy effectively suppressed the fluctuation of system frequency caused by load changes and improved the stability of system frequency.
KUPPUSAMY S, JOO Y H, KIM H S.Fault-tolerant load frequency control for DFIG-based interconnected wind power systems[J]. Information sciences, 2022, 582: 73-88.
PRASAD R, PADHY N P.Synergistic frequency regulation control mechanism for DFIG wind turbines with optimal pitch dynamics[J]. IEEE transactions on power systems, 2020, 35(4): 3181-3191.
ARANI M F M, MOHAMED Y A I. Analysis and impacts of implementing droop control in DFIG-based wind turbines on microgrid/weak-grid stability[J]. IEEE transactions on power systems, 2015, 30(1): 385-396.
MA J, ZHANG Y X, SHEN Y Q, et al.Equipment-level locating of low frequency oscillating source in power system with DFIG integration based on dynamic energy flow[J]. IEEE transactions on power systems, 2020, 35(5): 3433-3447.
TOULABI M, BAHRAMI S, RANJBAR A M.An input-to-state stability approach to inertial frequency response analysis of doubly-fed induction generator-based wind turbines[J]. IEEE transactions on energy conversion, 2017, 32(4): 1418-1431.