基于逐步线性回归的汽轮发电机组振动研究

Research of the Vibration of Turbine-generator Units Based on Linear Stepwise Regression

研究汽轮发电机组运行参数对基础振动的影响对降低振动引起的设备故障具有重要意义。建立汽轮发机组基础振动成因分析试验平台,首先测试不同汽轮机转速、进气压力与载荷工况下基础振动有效值,通过逐步线性回归对振动有效值与运行参数之间的关系进行统计分析,再根据汽轮机降速过程与增压过程中的基础振动时频图对统计分析结论进行验证。结果表明,汽轮发电机组基础的振动与汽轮机转速、载荷呈线性关系,且与汽轮机转速的线性关系更加显著;汽轮机转速对机组基础振动的影响比载荷影响更大,进气压力对基础振动的影响不显著;运用逐步线性回归统计方法可得出汽轮发电机组基础振动的影响因素及各影响因素的重要程度。

Research of the base vibration of turbine-generator units is significant for reducing the vibration which may transfer to the equipments connected to the base and lead to faults of the equipments. An experiment workbench for analyzing the base vibration was designed and built by mounting vibration isolators. The RMSs of the base vibrations for different turbine rotation speeds, air pressures at intake and generator＇ s loads were measured. Statistical analysis of the relationship between the operation parameters of the turbine-generator unit and the vibration RMS was carried out by means of linear stepwise regression. Finally, results from Statistical analysis were validated by time-frequency diagram of the base vibration in the processes of monotonically reducing the turbine rotation-speed and uprising the intake-pressure. The results show that the base vibration of the turbine-generator unit is linearly related to the rotation speed and the load of the turbine, and the linear relation with the rotation speed is more obvious than that with the load. The turbine rotation speed effects the base vibration more significantly than the load does, and the air pressure at the intake of the turbine has less effect on the base vibration. The linear stepwise regression method Can effectively elicit the factors which effect the vibration of the turbine-generator unit base, and reliably estimate the importance of each factor.