| 摘要 |
<p>A magnetic bridge comprising a magnetic circuit (1) having two ends; magnetic circuits (21a,21b) each having two ends and each having its one end connected to one end of the magnetic circuit (1); magnetic circuits (22b,22a) each having two ends and each having its one end connected to the other end of the magnetic circuit (1) and its other end connected to each of the magnetic circuits (21a,21b); a magnetic circuit (2) having two ends and having its one end connected to a junction between the magnetic circuits (21a,22b) and having its other end connected to a junction between the magnetic circuits (21b,22a); an exciting coil (3) disposed to generate a magnetic flux in the magnetic circuit (2); and a magnetic flux detecting coil (4) disposed to detect the magnetic flux of the magnetic circuit (1); wherein a current, which has been obtained by subjecting a current proportional to the voltage of a measured-electric-power line (5) to at least one of processings of intermittence and inversion, is caused to flow through the exciting coil (3); the current of the measured-electric-power line (5) is caused to flow through a detected-current conductor (5a); and wherein the output of the detecting coil (4) is synchronous detected by use of a signal having a doubled frequency in synchronism with the period of the intermittence or inversion.</p> |
