Improved hydrogenerator field winding thermal monitoring

A new monitoring method for determination of average hydrogenerator field winding temperature is introduced in order to increase the robustness measurement system using classic U-I method. The approach prone error due brush voltage drop, especially when low. Developed thermal model based on current and cold cooling air measurements, as well temperatures acquired from digital sensors mounted across winding. To monitor rotor generators with brushless excitation where measurements are not accessible, a mathematical was developed estimate existing medium sensors. Importance proposed arises foreseen widespread use distributed generation. models were compared their sensitivity examined thoroughly.