CAPACITOR DETERIORATION DETERMINATION METHOD AND OPERATION MACHINE

PROBLEM TO BE SOLVED: To provide a method determining capacitor deterioration highly accurately. SOLUTION: An internal resistance deterioration index depending on an internal resistance of the capacitor and changing monotonously relative to increase of the internal resistance, and a capacitance deterioration index depending on the capacitance and changing monotonously relative to decline of the capacitance, are calculated from measurement results of the internal resistance and the capacitance. A rectangle using as two diagonal vertexes, a starting point at which both an increase amount of the internal resistance and a decrease amount of the capacitance become zero and a tolerance limit point at which both the increase amount of the internal resistance and the decrease amount of the capacitance become each tolerance limit value, is defined in an orthogonal coordinate system using one index as one axis and the other index as the other axis. A first boundary line connecting a point on one side between a pair of sides in connection with the starting point of the rectangle to a point on the other side is defined. It is determined whether a point showing a present state shown by the calculated two indexes exceeds the first boundary line as a view from the starting point. The deterioration state of the capacitor is determined based on a determination result. COPYRIGHT: (C)2010,JPO&INPIT