| 摘要 |
PROBLEM TO BE SOLVED: To form a symmetrical construction and improve electrical characteristics by a method, wherein two DC connection conductors and two DC terminals are provided in each bridge branch and all the same polarity DC terminals of three bridge branches are connected to each other with adjacent conductors provided outside a vessel. SOLUTION: A bridge module is housed in a vessel 1 installed on a metallic bottom plate 2. A three-phase bridge having three power semiconductor branches is attached between the vessel 1, and the bottom plate 2 and each branch has two semiconductor switches. Two DC terminals 4 and 3, 7 and 6 or 10 and 9 are provided for each bridge branch. The negative polarity DC terminals 3, 6 and 9 are connected electrically to each other with a connection plate 12 provided outside the vessel. Similarly, the positive polarity DC terminals 4, 7 and 10 are connected electrically to each other with a connection conductor 14 provided outside the vessel. Both the DC connection plates 12 and 14 are laid adjacent to each other for maintaining an inductance lower than the inductance of an external DC circuit. |
