| 摘要 |
PROBLEM TO BE SOLVED: To prevent the air temperature in a closed type power conversion unit from exceeding a predetermined value. SOLUTION: In a cooling system that dissipates heat by transferring heat generated by a power semiconductor 11 to a refrigerant circulated by a cooling body 20 mounted with the power semiconductor and a pump 25 having an electric motor to dissipate the heat through an external radiator 23, and also collecting heat of a power converter control circuit 12 etc., which has been dissipated to the air in the closed type power conversion unit 10 by heat absorbing fins 21 thermally connected to the cooling body 20, a temperature sensor 26 detects the air temperature in the closed type power conversion unit 10, a rotational speed command circuit 27 computes a rotational speed command value based on the detected air temperature and set temperature, and an electric motor control circuit 28 performs driving control over the rotational speed of the pump 25 having the electric motor using the computation result as a command value, thereby keeping the air temperature in the closed type power conversion unit 10 at the predetermined value. COPYRIGHT: (C)2010,JPO&INPIT |
