Research on setting PID parameters of governor to trigger power oscillation of steam turbine unit

With the increasing complexity of the scale and structure of the power grid, the increase of the assistant adjustment system on the unit side improves the regulation performance of the unit, but has a negative impact on the dynamic stability, resulting in frequent power oscillation accidents. Within this paper, the models of turbogenerator speed control system and single machine infinite bus system are established, and the mechanism of steam turbine power oscillation caused by improper parameter setting of governor PID controller is analyzed. First, the change of system damping under different parameters is studied, and then the influence of the PI regulator commonly used in steam turbine governor load control loop on the system response is analyzed. It is found that improper setting of PID controller parameters will lead to power oscillation. Finally, the effects of the change of K p parameters on the speed, power, and damping of the system are analyzed in detail. When the K p increases, the stability of the system can be restored after a short oscillation, but the adjustment time is longer; if it increases too much, the system will lose steadiness and cause power fluctuation. This study helps optimize the parameter setting of the governor and enhance the stability of the mechanism.