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针对含规模化风电接入的交直流电力系统的频率稳定问题，以抑制风电出力大幅度随机扰动引起的频率波动为目的，提出了高压直流输电(high voltage direct current transmission，HVDC)附加频率控制(frequency control，AFC)和自动发电控制(automatic generation control，AGC)配合的辅助频率控制策略。该策略在风电出力发生大幅度随机扰动时，AFC利用HVDC功率快速调制和短时过载能力快速平衡风电出力扰动中变化较快的分量，控制器基于TLS-ESPRIT算法和改进射影控制理论设计，阶数低，易于工程实现；基于传统PI控制的AGC自动跟踪电网功率波动，调整调频机组出力平衡变化较慢的有功功率扰动分量，维持系统有功功率平衡，保持电力系统频率稳定。最后，利用PSCAD/EMTDC 在改造的四机两区域模型中进行了仿真分析，结果表明所提策略充分利用了交直流电力系统的频率调节能力，能较好地抑制风电出力引起的频率波动。“,”In order to stabilize the frequency fluctuation in AC-DC power system with large scale wind power integration, the coordination of high voltage direct current transmission (HVDC) auxiliary frequency control (AFC) and automatic generation control (AGC) was proposed. Taking advantage of fast modulation and short time overload capacity of HVDC, AFC quickly balanced the fast changing component of wind power fluctuation. AFC controller was designed based on TLS-ESPRIT algorithm and improved projective control. Since the order of AFC controller is low, it is easily used in practice. AGC based on traditional PI control automatically tracks the power fluctuation of the power system and adjusts the output of the selected generator to keep system active power balanced. Finally, a two-area power system was used to conduct the simulation with PSCAD/EMTDC. Results show that the proposed frequency strategy improves the frequency stability of the system.