| 摘要 |
<p>PURPOSE:To obtain a current transformer which can detect a DC current of several mA by a method wherein gaps are provided to two annular cores being in contact with each other at the part of the gaps and are separated at other parts and a Hall element is inserted into the gaps and exciting windings which induce magnetic fluxes which can be added are wound around the separated parts. CONSTITUTION:Gaps 8 are provided to two annular cores 6 and 7 and the two cores 6 and 7 get contact with each other at the part of the gaps 8 and are gradually separated at other parts. A Hall element 12 is inserted into the gaps 8 to apply a control current. Exciting windings 9 and 10 which induce magentic fluxes phi1 and phi2 which can be added are wound around the separated parts of the cores 6 and 7 and connected in series and a control current from an AC or DC source 11 is applied. With this constitution, a voltage V0, proportional to a current IDC to be measured which is applied to a wire 13 which passes through a window holl 14 of the cores is generated in the element 12.</p> |
