Capacitor deterioration judgment method
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsToshiaki Shimizu, Toshihiko Oohashi
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Abstract
A method for determining the deterioration of a capacitor that increases the measurement accuracy to have an improved reliability is disclosed. In this method for determining the deterioration of a capacitor, the deterioration of a capacitor including a pair of electrode bodies and electrolytic solution provided between the electrode bodies is determined by applying an AC voltage to the capacitor to measure an impedance characteristic at a frequency of the AC voltage. An inflection point appearing in the impedance characteristic due to the deterioration of the electrolytic solution is previously calculated to make comparison with an impedance value in the frequency region lower than the inflection point, thereby determining the deterioration.
Claims5
A method for determining deterioration of a capacitor including a pair of electrode bodies and electrolytic solution provided between the electrode bodies by applying an AC voltage to the capacitor to measure an impedance characteristic at a frequency of the AC voltage, comprising:
- previously calculating an inflection point appearing in the impedance characteristic due to the deterioration of the electrolytic solution to compare a characteristic value based on an impedance value in a frequency region lower than the inflection point with a predetermined characteristic value, thereby determining the deterioration.
Dependencies are inferred from the claim text.