Abstract: In the steam turbine generator,the temperature oflubricating oil has an important influence on the safe and stable operation of steam turbine system.In order to solve the problems of unstablity of lubricating oil caused by poor cooling water control quality of lubricating oil cooling system of gas-steam combined cycle unit,which reduced the oil film viscosity and bearing capacity of lubricating oil,corresponding modification of the cooling system equipment was conducted.The field test was used to obtain the opening degree and flow rate relationship data of the regulating valve.The K-means clustering algorithm was used to excavate the target data set of the valve opening-flow characteristics.Based on this characteristic,the characteristics were fitted by the least squares algorithm.The control strategy of lubricating oil temperature was optimized and applied to the actual system.According to the verification results,the control system of lubricating oil temperature corrected by the valve flow characteristics improves the temperature control quality,reduces the operation of the operating personnel,and effectively improves the safety and stability of the unit operation.