An instrument for the accurate measurement of water content in turbine oil

Turbine oil is widely used in many industrial applications. The presence of water increases the corrosivity of turbine oil and may cause adverse effect in the applications. So, water content is one of the most important properties of turbine oil, and it has great significance to measure the water content. In this paper, an available method of accurately measuring the water content in turbine oil is described. The method is based on the resonant cavity perturbation theory. By surveying the change of microwave resonant frequency in the cylindrical cavity, the effective relative dielectric constant is calculated, and the relationship between water content and the resonant frequency is derived. Then, a practical instrument is presented including the system composition and working procedures. Furthermore, designs and implements of individual parts of the system are also discussed. Finally, measure accuracy of the practical instrument is analyzed.