| 摘要 |
PROBLEM TO BE SOLVED: To relax bias of a cut-off current between power semiconductor elements connected in parallel which is caused by a difference in turning on/off operation time caused by a difference in characteristic of power switching elements connected in parallel, for improved reliability, to allow application of elements of low current rating and breakdown strength, with lower cost.SOLUTION: A figure shows a circuit of single phase amount of a power conversion equipment that converts DC to AC, which is an example of a circuit configuration in which power switching elements are used in bi-parallel. Although each energization current is ILa≠ILb if there is a difference of characteristics in power semiconductor elements 6a and 6b, by presenting such gate drive circuit configuration as gate currents IGa and IGb appropriate for the characteristic of 6a and 6b are made to flow, a time lag required for turning on/off is relaxed to provide ILa≒ILb, which allows suppressing concentration of a main circuit current to one power semiconductor element connected in parallel. The figure shows an example of bi-parallel, and the present invention is effective regardless of the number of parallel connections. |
