| 摘要 |
<p>PURPOSE:To analyze a factor for uneven parallel operation between unit elements quantitatively, by cutting fine grooves in a post electrode pressure- welded on one main electrode of a semiconductor control element to measure current with a Rogowskii coil imbedded therein. CONSTITUTION:Five grooves are cut in an electrode 1 for pressure welding in a ring. Rogowskii coils 3 are imbedded into the grooves. Difference from the case of the actual mounting lies in the grooves cut in the pressure welding electrode 1 to imbed the Rogowskii coils. The Rogowskii coils are made finer to lessen the groove width so that grooves of the pressure welding electrode will not cover a cathode electrode of each unit element. Hence, contact area between the cathode electrode of the element and the pressure welding electrode is the same as that in the actual mounting. Thus, a GTO element is driven using the electrode of such a type thereby enabling the measuring of a current distribution within the element in the state almost the same as that of the actual mounting.</p> |
