Abstract
On condition monitoring of electric point machine in railway, switching load and operation torque of motor are important parameters for estimating its health. At point machine condition monitoring devices, estimated switching load and estimated torque by motor current and voltage are normally used as easy to measure, however these estimated values have errors against real values occasionally at cases of switch malfunctions. By these errors, monitoring devices may had been missed some indication of switch malfunctions. In this study, we measured switching load and operation torque of an output axis of a clutch, which is set between a motor and gear mechanisms, and compared output of a monitoring device’s estimated values on tests using a real turnout and a test bed. By the tests, we confirmed that the differences of estimation are affected by errors of estimated rotation angle of operation gear and slip of a clutch. In addition, we proposed a correction method of estimated load and torque by degree of clutch slip which is a difference between estimated motor rotation speed and measured rotation speed of output axis of clutch.
