Performance Diagnosis using Optical Torque Sensor for Selection of a Steam Supply Plant among Advanced Combined Cycle Power Plants

Abstract

A newly developed optical torque sensor was applied to select a steam supply plant among advanced combined cycle, i.e. ACC, power plants of the Tokyo Electric Power Company. The sensor uses laser beams focused on small stainless steel reflectors having bar-code patterns attached on the surface of the rotating shaft, and a technique of signal processing using a correlation function featuring high frequency. The plant that supplied steam was selected on the basis of diagnosis of each steam turbine performance of the plants. Heat balance program was developed to analyze steam turbine performance using data of turbine output measured by the torque sensor and data measured by existing instruments of the power station. The steam turbine that supplied steam was determined by the present method using the optical torque sensor. The accuracy of the method to determine the steam supply plant was analyzed. It was then confirmed that the accuracy was greatly improved as compared with that of existing method.