摘要
次同步低频振动造成转子动力失稳是旋转机械的一种主要振动故障。一般的经验认为,次同步失稳转子的低频振动主要由轴承失稳(油膜涡动、油膜振荡)、汽流激振导致。对大型同步调相机组发生的次同步低频振动失稳故障进行建模分析,应用Riccati传递矩阵法核算调相机转子固有频率和稳定性,然后根据Hertz接触定律数值模拟碰摩状态下调相机转子的振动响应波形、频谱,研究动静碰摩诱发转子次同步低频振动故障的机理和故障特征,排除了普遍认为的调相机轴承失稳的原因,同时纠正了碰摩主要导致转子工频振动的传统认知,确定动静碰摩是调相机低频振动的主要诱因,指导现场检修消除碰摩故障,调相机运行恢复正常。深化了对调相机次同步低频振动故障的认知,可为同类机组振动治理提供有益参考。
Sub-synchronous low-frequency vibration causing rotor dynamic instability is a major vibration fault in rotating machinery.General experience suggests that the low-frequency vibrations of sub-synchronously unstable rotors are mainly caused by bearing instability(film whirl and oil film oscillation)and airflow excitation.This paper conducts a modeling analysis of the low-frequency vibration fault occurring in large synchronous condensers due to sub-synchronous instability.The Riccati transfer matrix method is applied to calculate the natural frequencies and stability of the condenser rotor.Subsequently,numerical simulations based on Hertz's contact theory are performed to analyze the vibration response waveforms and spectra of the condenser rotor under contact conditions.This study investigates the mechanism and fault characteristics of rotor sub synchronous low-frequency vibration faults induced by contact and non-contact interactions,eliminating the commonly held belief regarding the instability fault of the condenser bearings.Additionally,it corrects the traditional understanding that contact mainly leads to rotor operating frequency vibrations,confirming that contact interactions are the primary cause of low frequency vibrations in condensers.The findings guide on-site repairs to eliminate contact faults,allowing the condenser to return to normal operation.This deepens the understanding of sub-synchronous low-frequency vibration faults in condensers and provides useful references for vibration management in equipment.
作者
汪海洋
刘晓锋
刘一丹
何小锋
蔡丹
WANG Haiyang;LIU Xiaofeng;LIU Yidan;HE Xiaofeng;CAI Dan(State Grid Jiangsu EHV Company,Nanjing 211102,China;Jiangsu Frontier Power Technology Co.,Ltd.,Nanjing 211102,China;Nanjing NR Electric Co.,Ltd.,Nanjing 211102,China)
出处
《山东电力技术》
2025年第6期86-94,共9页
Shandong Electric Power
基金
国家电网有限公司科技项目“调相机组高可靠性非电量保护关键技术研究及应用”(5500-202316163A-1-1-ZN)。
关键词
调相机
低频振动
转子失稳
动静碰摩
condenser
low frequency vibration
rotor instability
dynamic and static rubbing
