低频振荡一直是影响电力系统安全稳定运行的重要问题，安装电力系统稳定器对于负阻尼机制起到了很好的抑制作用，但是对于共振机制还没有很好的对策。目前国内处理方法为减小线路潮流、提高电压，花费时间长并且有时没有效果、最终造成机组跳闸解列。通过对汽轮机控制策略的分析、建立相应模型和仿真实验可以证明，汽轮机控制系统主控制器和功率反馈回路发生故障而造成电网发生共振机制的低频振荡时，切为“阀位控制”是迅速平息低频振荡的最简单而快速有效的办法，并能够避免汽轮机组跳闸解列对电网造成的冲击。

Low-frequency oscillation is a main factor affecting the safe and stable operation of the power system. Installation of the power system stabilizer has effectively inhibited negative damping, but there is not a good method capable of dealing with the resonance mechanism. For the time being, domestic methods involving minimizing tidal current and enhancing voltage, are time-consuming and occasionally inoperative, which, as a result, leads to unit tripping. Turbine control logic was analyzed, and the corresponding model was established. The simulation test and real example show that, if the main controller of the turbine control system and the power feedback are out of work, switching the turbine control method to “valve control” is a simple and effective method for subsiding low-frequency oscillation and avoiding attacking power system during the turbine tripping.