| 摘要 |
PROBLEM TO BE SOLVED: To provide a current sensor capable of detecting a wider range of current than conventional current sensors.SOLUTION: Magnetic flux corresponding to the level of a detection signal is cumulatively induced on a core member 21 of a current sensor 1, but due to the characteristic of the core member 21 itself, magnetic permeability μ decreases from a peak at an external magnetic field H=0 and curvature of a μ-H curve defined by the external magnetic field H and the magnetic permeability μ increases with an absolute value of the external magnetic field H. With this characteristic, at an arbitrary point on a quadratic curve, an output signal of a detection coil 25 whose amplitude changes along a y-axis responding to an excitation signal whose amplitude changes along an x-axis is superimposed with a high frequency component that depends on the curvature of the quadratic curve, but since the center of swing of the excitation signal is on the quadratic curve, a unique high frequency component corresponding to the magnetic field H is superimposed on the output signal over a wide range of the magnetic field H from the vicinity of the magnetic field H=0 to a magnetic field Hs corresponding to a saturated magnetic flux density Bs. |
