| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To accurately measure a magnetic field of wide band frequency with a wide dynamic range continuously. <P>SOLUTION: This provides a leakage magnetic field measuring method. Magnetic fields with a very low frequency characteristic and a high frequency characteristic are measured with a first and a second three-axis magnetic sensors 1, 2 whose three magnetic sensing parts are crossed to each other. Each analog voltage signal of X, Y and Z axis components of which the magnetic field measured with both three-axis magnetic sensors 1 and 2 are magneto-electrically converted is output from the signal processors of each axis component. Using the signal converted from this analog voltage signal to digital signal with a high sampling period, instantaneous magnetic filed waveform data of one axis component common to the both three-axis magnetic sensors 1 and 2 are individually frequency-analyzed. A matching coefficient for matching the spectrum values of the both three axis magnetic sensors 1 and 2 at specific frequency fs arbitrarily specified by using the data is calculated. By using the matching coefficient, correction calculation is performed for all spectrum values to be corrected. By matching the frequency characteristic of the magnetic field of the very low frequency characteristic and the high frequency characteristic, a leakage magnetic field is measured. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
