Reactor cooling structure

1. A reactor cooling structure comprising:

a plurality of reactors that are stacked on one another in a stacking direction, each reactor including a coil, which is configured to produce magnetic flux when energized, and a core integrated with the coil; and

a cooling mechanism that cools the plurality of reactors, wherein:

each of the reactors has an exterior member housing the coil and the core of the reactor, the exterior member having:

first heat radiation surfaces respectively provided on both sides of the corresponding one of the reactors in the stacking direction of the stacked reactors; and

second heat radiation surfaces respectively provided on both sides of the corresponding reactor in a direction perpendicular to the stacking direction,

the first and second heat radiation surfaces being arranged to cool the coil of the corresponding reactor;

the cooling mechanism includes a cooling flow path for directly cooling by a refrigerant the first and second heat radiation surfaces of the exterior member of each of the reactors;

all the first and second heat radiation surfaces of each of the reactors (i) are arranged to face the cooling flow path and (ii) are made of a predetermined material;

the plurality of reactors include a first reactor and a second reactor adjacent to each other in the stacking direction;

the exterior member of the first reactor and the exterior member of the second reactor respectively have joint surfaces to join to each other;

one of the heat radiation surfaces of the first reactor and one of the heat radiation surfaces of the second reactor are respectively arranged as first and second adjacent heat radiation surfaces to face each other; and

the first and second adjacent heat radiation surfaces partition a part of the cooling flow path of the cooling mechanism.

2. The reactor cooling structure according to claim 1 , wherein,

one of the joint surface of the exterior member of the first reactor and the joint surface of the exterior member of the second reactor is engaged with the other thereof to thereby join the exterior member of the first reactor to the exterior member of the second reactor.

3. The reactor cooling structure according to claim 1 , wherein,

the joint surface of the exterior member of the first reactor and the joint surface of the exterior member of the second reactor are sealed to each other via a seal member.

4. The reactor cooling structure according to claim 3 , wherein the coil of each of the first and second reactors is configured to have an external connection terminal for connection to a power source, and the external connection terminal of the coil of each of the first and second reactors protrudes from a position separated from the seal member as seen in the stacking direction.

5. The reactor cooling structure according to claim 1 , wherein the coil of each of the reactors is configured to have an external connection terminal for connection to a power source, and the external connection terminal of the coil of each of the reactors protrudes from a predetermined position thereof, a position of the coil of each of the reactors being arranged to overlap the external connection terminal of the coil of another reactor in the stacking direction.

6. The reactor cooling structure according to claim 1 , wherein,

the exterior member of each of the reactors has a communication hole that communicates with the cooling flow path, and

the communication hole constitutes at least one of:

a refrigerant introduction flow path for introducing the refrigerant into the cooling flow path; and

a refrigerant discharge flow path for discharging the refrigerant from the cooling flow path.

7. The reactor cooling structure according to claim 1 , wherein the exterior member of each of the reactors is made from a resin material.

8. The reactor cooling structure according to claim 7 , wherein the resin material has heat conductivity.

9. The reactor cooling structure according to claim 1 , wherein the exterior member of each of the reactors is made from a metal material.

10. The reactor cooling structure according to claim 1 , wherein

the exterior member of each of the reactors has a substantially rectangular parallelepiped shape and has lateral sides, a lateral direction along each of the lateral sides being orthogonal to the first and second heat radiation surfaces of the exterior member of the corresponding one of the reactors, and

the reactors are stacked such that the lateral directions of the external members of the respective reactors are aligned as the stacking direction.

11. The reactor cooling structure according to claim 10 , wherein each of the reactors is configured such that the lateral direction of the exterior member of the corresponding one of the reactors is orthogonal to a winding axis direction of the coil of the corresponding one of the reactors.

12. The reactor cooling structure according to claim 10 , wherein each of the reactors is configured such that the lateral direction of the exterior member of the corresponding one of the reactors is arranged to align with a winding axis direction of the coil of the corresponding one of the reactors.

13. The reactor cooling structure according to claim 1 , wherein:

the core of each of the plurality of reactors (i) is made of magnetic powder-mixed resin and (ii) is arranged inside and outside of the corresponding coil;

the external member of each of the reactors has inner wall surfaces in the stacking direction, the inner wall surfaces of the external member of each of the reactors being arranged to face the respective first heat radiation surfaces of the external member of the corresponding one of the reactors; and

the core of each of the reactors is arranged to be in contact with the inner wall surfaces of the exterior member of the corresponding one of the reactors.

14. The reactor cooling structure according to claim 1 , wherein each of the reactors constitutes an inverter circuit of a power conversion apparatus together with a semiconductor module that contains a semiconductor element arranged along a plane orthogonal to the stacking direction.

15. A reactor cooling structure comprising:

a plurality of reactors that are stacked on one another in a stacking direction, each reactor including a coil, which is configured to produce magnetic flux when energized, and a core integrated with the coil; and

a cooling mechanism that cools the plurality of reactors, wherein:

each of the reactors has an exterior member housing the coil and the core of the reactor, the exterior member having:

first heat radiation surfaces respectively provided on both sides of the corresponding one of the reactors in the stacking direction of the stacked reactors; and

second heat radiation surfaces respectively provided on both sides of the corresponding reactor in a direction perpendicular to the stacking direction,

the first and second heat radiation surfaces being arranged to cool the coil of the corresponding reactor;

the cooling mechanism includes a cooling flow path for directly cooling by a refrigerant the first and second heat radiation surfaces of the exterior member of each of the reactors;

all the first and second heat radiation surfaces of each of the reactors (i) are arranged to face the cooling flow path and (ii) are made of a predetermined material;

the core of each of the plurality of reactors (i) is made of magnetic powder-mixed resin and (ii) is arranged inside and outside of the corresponding coil;

the external member of each of the reactors has inner wall surfaces in the stacking direction, the inner wall surfaces of the external member of each of the reactors being arranged to face the respective first heat radiation surfaces of the external member of the corresponding one of the reactors; and

the core of each of the reactors is arranged to be in contact with the inner wall surfaces of the exterior member of the corresponding one of the reactors.