发电机调速附加控制对系统频率稳定的作用

研究了基于复合偏差功率反馈的同步发电机调速系统附加控制方法及其对频率稳定的作用。该方法克服了传统调速控制因转子质量惯性、负荷特性和转速测量死区而造成的控制延时,并且能精确地进行不平衡力矩补偿,从而在扰动初期能进行及时有效的频率稳定控制。对单区域系统的仿真结果表明,汽轮发电机组和水轮发电机组附加调速控制相比传统调速控制而言,减小了频率的偏移幅度,抑制了频率振荡的发生;提前了锅炉燃烧系统对负荷变化的响应时间,从而提高了机组一次调频的持续力;水轮机组的闸门开合次数及频率也都有一定的减小;降低了机械功率的超调和振荡。

Effect of additional control on frequency stabilization of generator governing system

The additional control of generator governing system based on power feedback and its effect on frequency stability are studied,which conquers the control lag of conventional speed control, caused by rotor inertia,load characteristics and speed measurement dead band,and accurately compensates the imbalance torque to effectively control the frequency stability at the initial stage of disturbances.The simulation of an isolated power system demonstrates that,compared with conventional frequency control,the additional control decreases the frequency excursion of generator and restrains the frequency oscillation;speeds up the response of boiler combustion system to load change and improves the regulation capability of unit primary frequency;decreases the open-close times of hydraulic turbine gate;avoids the over-adjustment and oscillation of mechanical power.