COOLER

PROBLEM TO BE SOLVED: To provide a cooler which improves cooling performance without increasing the size of an apparatus.SOLUTION: A cooler has: a cooling container 10 housing a coolant 20 so as to have a space portion 12; a power module 30 including a semiconductor element 31 and provided so as to contact with the outer side of a portion of the cooling container 10 where the coolant fills; a first heat exchanger 40 provided at the space portion and in which a refrigerant 100 flows; a second heat exchanger 50 connecting with the first heat exchanger in parallel and cooling the coolant through heat exchange with the refrigerant; a flow control valve 60 controlling the flow rate of the refrigerant flowing through the second heat exchanger; coolant temperature detection means 70 detecting a temperature of the coolant; element temperature estimation means estimating a temperature of the semiconductor element from a current flowing through the semiconductor element; and control means controlling the flow control valve according to a difference between the temperature of the coolant and the temperature of the semiconductor element.