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Analysis showed that partial discharge properties are a critical indicator for capacitor failure mechanism.
This makes a low stress production test for end connection quality problematic since such tests can only show the total capacitor dissipation factor resulting from various factors.
The results of the study on 2912 capacitor banks including 8736 capacitors installed at 153 distribution substations showed that the failure mode of capacitor units may be represented by Weibull distribution and each capacitor manufacturer has different failure rate.
A novel soft-start circuit with controllable start-up time, high start-up speed, high stability, and no off-chip capacitor for a current mode DC-DC is proposed in this paper.
The model proposed in this paper can therefore be used to analyze capacitor starting systems accurately.
From these results the mechanical reliability of a capacitor can be estimated for different system applications and realistic limits can be determined for the allowable sizes and types of defects.
The experimental results show that all three methods can improve the lifetime of the capacitor to some extent.
Proceedings ArticleDOI
Barbaros Kirisken, H. Fatih Ugurdag 
17 Apr 2014
22 Citations
Results show that the optimized capacitor is not the cheapest, most expensive, or most reliable one; optimal capacitor is a modest Chinese “CAP.
This paper proposes a soft-start method with the features of a small on-chip capacitor and start stability for dc-dc converters.

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