| 摘要 |
PROBLEM TO BE SOLVED: To prevent an element from damage by effectively eliminating a phenomenon of abnormally heating of a certain element and generation of high surge voltage, in the case of driving a semiconductor element for electric power with two or more of the elements connected in parallel. SOLUTION: In the case of driving semiconductor elements IGBT1,2 for electric power connected in parallel from a gate drive circuit 15, a differential value of a current Ic1 flowing in the element IGBT1 in a side of temperature increasing is detected by a comparator 21, by driving a primary winding of a transformer 23 through an AND circuit 22 when an off-command 13 is given, voltage is induced in a secondary winding connected between gates of the elements, a gate potential of the element IGBT1 in a side of temperature increasing is raised, current unbalance of collector currents Ic1, Ic2 in both the elements is corrected. COPYRIGHT: (C)2004,JPO |
