The linear variable differential transducer(LVDT) is an important measuring component used to feedback the opening of valves in steam turbine servo system

which plays an important role in safe and stable operation of the steam turbine.On the basis of video processing

by using state fitting

target tracking and pattern recognition algorithm

this paper proposes an auto-monitoring technology for LVDT faults occurred on turbine governing valves

which can be used in industrial plants.Through the corner detection for LVDT video image target area

this technology judges the LVDT video image rod displacement

so as to determine the opening of the control valve.Then

combining with the field thermal instrument information

it determines whether the control valve LVDT fails.The technology can replace manual inspection and monitor the valve LVDT initiatively and continuously

which can effectively avoid the imbalance of turbine operation caused by LVDT faults not be found timely