Hydro generator efficiency assessment using infrared thermal imaging techniques

Calorimetric method has for a long time been applied for energy conversion efficiency measurement in electrical machines. The number of temperature sensors necessary for its successful application in the field constitutes in one of the major drawbacks of the method. The present paper shows how the usage of infrared (IR) thermal imaging techniques can reduce costs and the necessary time for the calorimetric method application. In addition, contribution to the heat transfer coefficient determination and a new approach to consider conduction losses in the generator shaft is also presented.