Development of AC current comparator based on coaxial cable for enlarging measurement frequency range up to 10 kHz

We have started a study in 2005 for enlarging the frequency range of the AC current measurement using a current comparator up to 10 kHz. In this study, it is the most important to make the error factor of the comparator clear and the intensity of them estimate. Therefore, we designed the new comparator aimed for the evaluation of the error experimentally. For improving reliability of self-calibration result at the comparator, a decimal system was adopted to winding construction. By observing the potential distribution at the coaxial cable at current comparison windings, it made dominant error current clearly. The nominal primary current of the comparator is 100 A, and range 1/1-1/500, of the ratio, the limit of the frequency is 10 kHz. By the ratio within 100, we assume the uncertainty of the comparator as the current ratio standard after correction to be the order of 50 muA/A.