Remaining useful life prediction of aluminum electrolytic capacitors used in wind turbines

Aluminum electrolytic capacitors are widely used in the converter systems of wind turbines. Though vital the capacitors are they are the “weak link” in wind turbines. Accurately predicting its remaining useful life is of great importance. However, traditional estimation methods are only applicable to the static operating conditions. This paper proposed an estimation method by introducing the virtual lifetime instead of the actual operating time to predict the equivalent series resistance (ESR) as well as remaining useful life of capacitor. Compared with measured ESR values, the model is reasonable for complicated operating conditions and is of practical significance in the prediction of capacitor's remaining useful life.