Electric material model aging for online diagnostic systems

Each electrical insulating material or system in large electric machines is precisely designed and later monitored in operation. The task for monitoring the state of the machine is information about rest life time of such as machine. The key element of electrical machine is its electroinsulating system. For proper rest life time calculation of an insulation system it is necessary to have complete information about acting degradation factors. When degradation is measured by on-line diagnostic system this data can be used for prediction of rest life time of its insulation. For “on-line” calculation of rest life time a mathematical or physical model can be employed. Objective for each on-line monitored electrical appliance is to have proper aging model for acting degradation factors. For each electroinsulating system subjected for on-line monitoring has to be known aging model. This model can be obtained by laboratory aging, and it is crucial for obtaining life time curve of the insulating material. In the laboratory conditions it is not an easy task to simulate all the processes proceeding in real application. This paper concern possible laboratory aging and their usage.