| 摘要 |
<p>PURPOSE:To miniaturize an equipment by using a current detection method suitable to a small iron core. CONSTITUTION:A first method uses the following; an iron core 15 wherein the magnetic hysteresis loop is rectangular, the coercive force is small, and the sectional area is small, an AC exciting coil 18 wound around the thick part of said iron core, a resistor 19 and an AC half-wave excitation power supply 20 connected in series with said coil 18, a DC excitation coil 19, and a resistor 22 and a DC excitation power supply 23 which are connected in series with the DC excitation coil 19. One of the above coils is excited with AC, and the other is excited with DC, in the manner in which the magnetic flux polarity is not inverted. When a magnetic field generated by a current to be detected which flows in a conductor 17 in the vicinity of the iron core is added, the magnetic field range moves and inverts the magnetic flux polarity. The current to be detected is obtained by using a pulse type induced voltage generated in a detection coil 24 wound around the iron core independently of the above two coils. A second method has the same constitution of equipments as the first method. An iron core having Matteuci effect is used. Without using the detection coil, it is directly picked up from a voltage induced in the iron core itself that the magnetic flux polarity of the iron core is inverted by the current to be detected.</p> |
