Theory and application of dynamic aging for life estimation in machine insulation

After a brief discussion on possible on-line indicators of aging, this paper presents a concept of dynamic aging theory (DAT). Based on the philosophy of a DAT, a dynamic multistress aging model is proposed. Necessary DAT formulation and software have been developed for testing the model against laboratory aging data. In this study, dynamic stagnation voltage (DSV), a derived partial discharge parameter, and the groundwall insulation response to a traveling acoustic wave have been found to be the most appropriate parameters for assessment of remaining insulation machine life. This approach is shown to be a meaningful and practical solution to a very complex problem. Although this study is in its initial stage, it does show significant promise as an on-line tool for dynamically predicting remaining life based on DAT and other appropriate feedback measures.

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