Life prediction model for aluminum electrolytic capacitors

The aluminum electrolytic capacitor used for DC bus filtering in motor drives is generally thought to be the weak link in motor drive life expectancy. Because, unlike other electronic components in a drive, it has a finite life due to wear-out failure. Although quality improvements have been made to these parts over the last few decades, little has been done to improve the methods used to predict their life. The model presented, based on the physics of the wear-out mechanism, tested favorably against actual data. The model is compared to the existing method which gives substantially more liberal predictions.