Monitoring system for over-temperature detection of water cooled rotor poles of hydro electrical generators installed at the Danube River Iron Gates Power Plant

In the field of temperature measurement, infra-red measuring methods, the only one which gives full information on surface temperature distribution of the observed objects, proves to be even more valuable when it is necessary to measure and monitor temperatures of moving objects. The advantage of being a passive method, with no interference on the thermal balance of the observed object, i.e. no changing influence of the temperatures to be measured, is again, even more appreciated in the case of moving objects, by the elimination of rather complex, stuffy and expensive system of probes, signals wiring and transmission devices, required in the case of conventional methods (thermocouple/thermoresistance). Based on a dedicated application, the article shows the criteria considered in the design stage, as well as in that of the implementation of a monitoring system for over-temperature detection of water-cooled rotor poles of hydro-electrical generators (HEG), all done in normal working conditions, i.e. with the HEG in movement. Two possible fixed implementations of a monitoring system, one of them in operation for over three years at the Danube River Power Plant, as well as a portable device, with same designation and practical similar results, are presented with field results which are discussed