| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique of preventing dew condensation using a component that is originally required by an inverter, in other words, provide a technique of preventing dew condensation without adding a component that is used only to prevent the dew condensation.SOLUTION: An inverter circuit and a water cooling type cooler are provided, with the inverter circuit including a semiconductor switching element and the inverter circuit and the water cooling type cooler being adjacent to each other. When the inverter circuit is water-cooled and a temperature of the inverter circuit becomes lower than an ambient temperature, a condition that dew condensation occurs at an inverter is satisfied. A control device is provided which increases, while the dew condensation occurrence condition is detected, the number of times of switching of the semiconductor switching element per unit time. When the number of times of switching per unit time is increased, a calorific value is increased, which eliminates the dew condensation occurrence condition. With the device according to the present invention, it is possible to prevent the dew condensation using the semiconductor switching element that is originally required by the inverter. |
