发电机组次同步振荡扭振参数甩负荷测试研究  

Reseach on Torsional Vibration Characteristics of Subsynchronous Oscillation in Load Rejection Test of Generator Unit

作　　者：徐珂 朱鑫要 解兵 王大江 李文博 吴盛军 XU Ke;ZHU Xin-yao;XIE Bing;WANG Da-jiang;LI Wen-bo;WU Sheng-jun(State Grid Jiangsu Electric Power Co.,Ltd.,Research Institute,Nanjing 211103,China)

机构地区：[1]国网江苏省电力有限公司电力科学研究院,南京211103

出　　处：《汽轮机技术》2023年第3期222-224,182,共4页Turbine Technology

摘　　要：提出一种利用甩负荷试验获取汽轮发电机组次同步振荡扭振参数的方法。甩负荷试验时汽轮机扭矩负载突降为0,转速飞升过程中激发出轴系扭转自由振动响应。利用频率计数法,从发电机组保护系统转速传感器输出信号中提取瞬时角速度,通过数值积分方法获取扭角位移信号。测试发现,相比于扭角速度,扭角位移信号更能反映扭振特征。甩负荷试验时扭振信号比较微弱,测速齿轮盘分度误差、振动、齿轮盘安装偏心等对测试结果影响较大。这类误差具有周期性特点,滤除瞬时角位移信号中转频及其若干倍倍频谐波分量后,信号中包含的扭振特征明显。结合某热电联产项目汽轮发电机组甩负荷试验进行了测试,给出了信号处理方法,验证了方法可行性。该方法无需对轴系施加扭矩激励,具有较高的工程应用价值。The paper presents a method for obtaining torsional vibration characteristics of the subsynchronous oscillation of generator units by load rejection test.The generator torque load suddenly drops to 0,and the shaft free torsional vibration response is excited during the speed rise process of load rejection test.The frequency counting method is used to extract the instantaneous angular velocity from the output signal of the speed sensor of the generator protection system.The angular displacement signal is obtained through the numerical integration method.Angular displacement signal reflects torsional vibration characteristics better compared with that of angular velocity signal.The torsional vibration is weak during load rejection test.The indexing error and eccencity of speed measuring gear and vibration have a great influence on the test results.Considering the periodicity of the error,the shaft torsional vibration signal can be accurately extracted after filtering the synchronous and several times of the synchronous components.The paper gives the signal processing method.The feasibility of the method is verified combined with the load rejection test of a steam turbine generator unit.This method does not need to apply torque excitation to the shaft and has strong engineering application value.

关 键 词：汽轮发电机 次同步振荡 扭振 甩负荷 固有频率 

分 类 号：TM621.27[电气工程—电力系统及自动化]