Patent ID: 6473699
Filing Date: 2002-10-29
Classification: G01R

Abstract:
A power arithmetic apparatus comprising:means for detecting a first variation amount in a voltage in proportion to a voltage of a measuring object and a second variation amount in a voltage in proportion to a current of the measuring object; and means for calculating power of the measuring object based on the first variation amount detected and the second variation amount detected; wherein the means for detecting the first variation amount and second variation amount comprises: a first converter for converting the voltage in proportion to the voltage of the measuring object to a first digital signal indicating the voltage in proportion to the voltage of the measuring object; a second converter for converting the voltage in proportion to the current of the measuring object to a second digital signal indicating the voltage in proportion to the current of the measuring object; a first counter for outputting the first variation amount based on the first digital signal; and a second counter for outputting the second variation amount based on the second digital signal.