| 摘要 |
<p>With an electric power conversion system, miniaturization of the system is aimed at while reduction of rise in temperature is achieved by sufficiently securing a cooling operation by a cooling fan. The electric power conversion system is provided with a casing for covering cooling fins for cooling power semiconductors, a main circuit board having a driver circuit for driving the power semiconductors, and a cover for covering up the main circuit board. The system includes a first air-flow hole provided at a part of the main circuit board, on the upper side of an air-intake provided in the cover, and a second air-flow hole provided on the lower side of the first air-flow hole, and on the lower side of the cooling fins, wherein air from the second air-flow hole is caused to flow to the cooling fins by a cooling fan.</p> |
