汽轮机阀门流量特性对电力系统的影响及其控制策略

汽轮机阀门流量特性是影响电力系统稳定性的重要因素,通过建立电网汽轮机及其调速系统、发电机、励磁系统的数学模型,研究了汽轮机调节阀门流量特性对电网安全稳定性的影响机制。数学分析和仿真结果表明,当汽轮机阀门流量特性不佳时,会引起原动机有功功率的周期性波动。针对此现象,提出了调整后的汽轮机调速系统控制策略,该策略能够抑制功率控制方式下的比例—积分—微分控制器的过度调节,有效增加系统阻尼,抑制原动机的功率波动。

Influence of Steam Turbine Valve Discharge Characteristics on Power Systems and Its Control Strategy

Steam turbine valve discharge characteristics are among the important factors affecting the stability of the power systems.The influence mechanism of steam turbine valve discharge characteristics on the security and stability of the power grid is studied through the mathematical modeling of steam turbine and its speed control system,generator and excitation system.Mathematical analysis and simulation results show that cyclic fluctuations of generator active power might be caused by undesired steam turbine valve discharge characteristics.In view of this phenomenon,a modified control strategy of turbine governor modification system is proposed.This strategy can inhibit the excessive accommodation of proportion-integration-differentiation(PID) controller which is based on the power control mode,effectively increases the system damping,and suppresses power fluctuations of the prime mover.