Real-time online monitoring and fault diagnosis are extremely important to guarantee normal operation of equipments of large rotating machinery

these devices include power plant generating set

marine gas turbine

steam turbine

etc. Design a measurement system based on rotating mechanical axis orbit and of oil film thickness measurement system. The system consists of eddy current displacement sensor

temperature sensor

acceleration sensor

data acquisition equipment and measuring software. Establish mathematical model for calculation of axis orbit and oil film thickness. Through generalized polynomial fitting based on least squares method to compensate data of eddy current sensor

and effectively improve measurement precision of the system

and through test

under different working conditions

verify test performance of system. Experimental results show that the measurement system has strong anti-interference ability

stable and reliable running

test linearity can reach 0. 05 %.