| 摘要 |
PROBLEM TO BE SOLVED: To obtain an NPC inverter equipment wherein a positive side main circuit or a negative side main circuit is mounted on a module unit, setting the neutral point of DC power as a boundary. SOLUTION: In a power module unit 51, a positive side main circuit and a negative side main circuit are constituted, setting neutral clamping diodes 52a, 52b as a boundary. For example, in the positive side main circuit, the neutral point clamping diode 52a is set as a starting point, and the following are arranged in order; a GTO element 53a, a flywheel diode 54a, a GTO element 53b and a flywheel; diode 54b. Between the GTO elements and the flywheel diodes, a water-cooled heat sink 55 is arranged without insulation. A snubber circuit, a recovery diode 60a and an abode reactor 61a are connected with the heat sink. |
