Dissolved oxygen in pure water supplied to power plant may cause corrosion of piping arrangements, condensers or turbine's blades. For preventing accidents from corrosion, therefore, it is essential to measure the concentration of Dissolved oxygen in real-time.
In this paper we present a method of measuring dissolved oxygen very accurately up to ppb units. This method, called polarographic method, is based on the measures of the electric current generated by the oxidation process in cathode and deoxidation process in anode, assuming that the amount of the current is proportional to the density of dissolved oxygen. We introduce algorithms for the compensation of temperature and atmospheric pressure to reduce measuring errors and multiple amplification ratio algorithm to amplify small current.
Effectiveness of the suggested method is verified through a series of experiments in the real power plant field.