Abstract:Torque-limited inertial control (TLIC) offers advantages of stabilizing wind turbine (WT) operation and mitigating secondary frequency dip. When large-scale wind farm (WF) clusters simultaneously employ TLIC to provide power support, unnecessary frequency recoil (FR) phenomenon may occur, persistently degrading the frequency regulation performance. To address this issue, the paper analyzes the frequency response characteristic under TLIC method, and derives the conditions for FR under simultaneous and immediate support and simultaneous and delayed support, with the latter exhibiting more pronounced FR effects. The root cause of FR is identified as excessive power increments. Hence, the multi-turbine cooperative frequency regulation control method for WFs considering the TLIC power characteristics is proposed. By sequentially activating TLIC among WTs, the excessive power increment from simultaneous support is mitigated, and the gradual power reduction of the engaged WTs can be compensated. Experimental validation is conducted based on the test bench of wind-integrated power system, which demonstrates that the proposed method effectively avoids FR and further enhances the frequency nadir.