摘要
振动保护逻辑设计对机组安全运行影响较大,采用正交方向上两个轴振信号组合逻辑设计模式可以有效地降低单点保护误动概率。建立了机组转子—轴承系统动力学模型,分析了正交方向上两个轴振信号之间的关联性。研究结果表明,轴承动力特性和振动响应受轴承载荷的影响较大,不同载荷下轴心轨迹形状会发生较大改变,两个方向上轴振幅值比可以在一个比较大的范围内变化。轴承载荷越大,X方向和Y方向的幅值比越大,越容易导致振动保护系统拒动。振动保护逻辑设计时,轴振跳机值可参照国际标准,而报警值则建议参照机组历史运行记录,在历史值基础上增加30~50μm。
There is large influence of vibration protection logic design on the safe operation of turbo generator unit. The combined vibration logic design using shaft vibration signals in two perpendicular directions can reduce the misoperation probability of protection system effectively. A rotor bearing dynamic model is sets up to research the relationship between two shaft vibration signals. It is pointed that bearing dynamic characteristics and bearing vibration are influenced by its load largely. Shaft orbit shape and amplitude ratio between two shaft vibration signals changes a lot in different bearing load cases. Vibration amplitude ratio in two directions increases with the increase of bearing load. Misoperation of protection system may occur easily in this condition. The shaft vibration action value can be designed according to the international standard while the alarming value should be designed on the base of unit history values. 20-30 μ m more than that of the history mean value is reasonable.
出处
《电站系统工程》
2016年第1期17-19,共3页
Power System Engineering
关键词
汽轮发电机组
振动
保护
turbo generator unit
vibration
protection
