JP2015170753A - Reactor with cooler and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology which prevents an eddy current from being caused in a cooler by magnetic flux leaked from a core and prevents unnecessary heat generation of the cooler in a reactor with the cooler in which the cooler is buried in the core formed by a resin containing magnetic material particles.SOLUTION: A reactor with a cooler includes: a core 3 which is hardened by a resin containing magnetic material particles so that the resin fills the inner side of a coil 2 and covers the outer side of the core 3; and a cooler 4 which is buried in the core 3 so as to face the coil 2. The cooler 4 is made of an insulative resin.

Description

  The technique which this specification discloses is related with the reactor with a cooler, and its manufacturing method.

  An electric vehicle including a hybrid vehicle is equipped with a power converter for converting the electric power of the battery into electric power supplied to the traveling motor. The motor mounted on the electric vehicle has a high output. Therefore, the power converter may be provided with a voltage converter circuit for boosting the voltage of the battery together with the inverter circuit. The voltage converter circuit is typically a chopper type boost converter circuit. The chopper type boost converter circuit is provided with a reactor for storing electric energy in the boost operation. A large current flows through the reactor to support high-output motors. Therefore, the reactor generates heat due to the load. Patent Document 1 discloses a reactor including a cooling member in order to suppress a temperature rise of the reactor due to heat generation. The voltage converter circuit may include a step-down circuit that steps down the regenerative power from the traveling motor. In such a case, the voltage converter circuit is a chopper type buck-boost converter circuit.

  The reactor disclosed in Patent Document 1 is for cooling the reactor on a core made of a resin (referred to as magnetic powder mixed resin in Patent Document 1) containing magnetic particles filled inside and outside the coil. The cooling member (cooling pipe) is embedded. With this configuration, the heat generated by the coil of the reactor is transmitted to the core, and the heat is absorbed by the cooling member embedded in the core. Patent Document 1 also discloses a manufacturing method thereof. First, a coil and a cooling member are disposed at predetermined positions in the case. The fluid magnetic powder mixed resin is poured into the case, and then the fluid magnetic powder mixed resin is solidified by maintaining a predetermined temperature for a predetermined time. A core is formed by the solidified magnetic powder mixed resin. With this manufacturing method, the cooling member can be easily embedded in the core. And since magnetic powder mixed resin adheres well to the case inner surface and the surface of a cooling member, the heat-transfer efficiency from a core to a cooling member and a case improves.

JP 2007-335833 A

  A magnetic powder mixed resin core as shown in Patent Document 1 has a lower magnetic permeability than a core made of a lump of magnetic material, and magnetic flux tends to leak. On the other hand, a metal having a high thermal conductivity (typically aluminum or copper) is used for the material of the cooler. Patent Document 1 also states that the cooling member and the case are preferably made of aluminum. However, if a conductive metal is in close contact with the magnetic powder mixed resin core where magnetic flux easily leaks, the magnetic flux leaked from the core induces eddy currents in the metal, and the eddy currents generate heat. Even if a cooling member or case using aluminum having high thermal conductivity is brought into close contact with the core, the cooling member or case itself generates heat, and the expected cooling performance cannot be obtained.

  The technology disclosed in this specification was created in view of the above problems. The purpose of the reactor is a reactor with a cooler in which a cooler is embedded in a core made of resin containing magnetic particles, preventing eddy currents from being generated in the cooler by magnetic flux leaking from the core, and generating unnecessary heat. It is to prevent.

  The reactor with a cooler disclosed in this specification includes a core solidified with a resin containing magnetic particles so as to fill the inside of the coil and cover the outside, and a cooling embedded in the core so as to face the coil Equipped with a bowl. The cooler is made of an insulating resin. Note that “the cooler is embedded in the core” does not require that the entire cooler is covered with the core, and it is sufficient that a part of the cooler is embedded in the core.

  According to this structure, since the location where the cooler is embedded is not filled with the resin containing the magnetic particles, the magnetic flux leaking from the location passes through the cooler. However, since the material of the cooler is an insulating resin (a different type of resin from the resin including the magnetic particles), no eddy current is generated in the cooler. Therefore, heat generation of the cooler due to eddy current is prevented.

  Further, the magnetic flux density of the magnetic flux generated from the coil increases as the position is closer to the coil. However, according to the above configuration, since the eddy current is prevented from being generated in the cooler, the cooler does not generate heat even in a place where the magnetic flux density is high. That is, as the cooler is closer to the coil, only the advantage of improved cooling performance can be enjoyed.

  Not only the cooler but also a pipe (refrigerant supply pipe) for sending the refrigerant to the cooler and a pipe (refrigerant discharge pipe) for discharging the refrigerant from the cooler are preferably embedded in the core to contribute to cooling of the coil. That is, the reactor extends from a surface (coil facing surface) facing the coil of the cooler so that the refrigerant supply pipe and the refrigerant discharge pipe penetrate the core, and the refrigerant supply pipe and the refrigerant discharge pipe are connected to the coil. It is good to arrange | position at the both sides of a coil, when it sees from the direction orthogonal to an opposing surface. Furthermore, the coil may be formed in a square cylinder shape, and the cooler, the refrigerant supply pipe, and the refrigerant discharge pipe may be disposed so as to surround the three side surfaces of the square cylinder shape of the coil. Since not only the cooler but also the refrigerant supply pipe and the refrigerant discharge pipe absorb the heat of the coil, the cooling efficiency is further improved. Of course, the refrigerant supply pipe and the refrigerant discharge pipe are preferably made of an insulating resin.

  Said reactor with a cooler can be manufactured with the following method. First, a coil and a cooler (and a refrigerant supply pipe and a refrigerant discharge pipe) are put into a mold. Thereafter, the mold is filled with resin containing fluid magnetic particles at a predetermined pressure and a predetermined temperature. Thereafter, the resin including the magnetic particles is hardened along the shape of the mold, whereby the reactor with the cooler is formed.

  By manufacturing as described above, the coil and the cooler (and the refrigerant supply pipe and the refrigerant discharge pipe, hereinafter, the refrigerant supply pipe and the refrigerant discharge pipe are collectively referred to as a refrigerant pipe) are embedded in the core, and the cooler (and the refrigerant Tube) can be formed integrally with the reactor. When a plurality of reactors with a cooler are manufactured by integrally forming the cooler and the reactor, it is easy to manage the variation in distance between the coil embedded in the core and the cooler (and the refrigerant pipe). can do. The variation in distance causes the variation in the heat dissipation performance of the reactor.

  Also, it is better to put a coil and a cooler into a mold, and then flow and solidify a fluid resin (resin containing magnetic particles for the core) into the mold and then bond the cooler and the core separately. However, since the adhesiveness between the core and the cooler is increased, the heat transfer between the core and the cooler is improved.

  This specification also provides the lamination | stacking unit using the reactor with said cooler. An example of the structure is as follows. The stacked unit includes the above-described reactor, a plurality of cooling plates, and a plurality of power cards that accommodate switching elements. The reactor, the plurality of cooling plates, and the plurality of power cards are stacked. The stacking unit includes a cooling plate supply pipe for supplying a refrigerant to each cooling plate, and a cooling plate discharge pipe for collecting and discharging the refrigerant from each cooling plate. The cooling plate supply pipe and the cooling plate discharge pipe penetrate the plurality of cooling plates along the stacking direction. The cooling plate supply pipe is connected such that the center line of the cooling medium supply pipe matches the reactor supply pipe, and the cooling plate discharge pipe is connected so that the center line of the cooling plate discharge pipe matches. One of the plurality of cooling plates is in contact with the side surface of the reactor opposite to the cooler. Here, the cooling plate and the side surface of the reactor may be in contact with each other via a heat dissipation sheet. The coil of the reactor is sandwiched between the embedded cooler and the cooling plate of the laminated unit, and is cooled more efficiently.

  According to the technology disclosed in this specification, in a reactor with a cooler in which a cooler is embedded in a core made of resin containing magnetic particles, eddy current is prevented from being generated in the cooler due to magnetic flux leaking from the core. It is possible to prevent the cooler from generating heat. Details and further improvements of the technology disclosed in this specification will be described in the following “DETAILED DESCRIPTION”.

It is a typical perspective view of the reactor with a cooler of an Example. It is sectional drawing of the reactor with a cooler in the II-II line | wire of FIG. It is sectional drawing of the reactor with a cooler in the III-III line of FIG. It is sectional drawing of the reactor with a cooler in the IV-IV line of FIG. It is a typical perspective view which shows the manufacturing method of the reactor with a cooler of an Example. It is sectional drawing which looked at the reactor with a cooler of another Example from the same cross section as FIG. It is a block diagram of the electric power system of the power converter using the reactor with a cooler of an Example. It is a schematic plan view of the lamination | stacking unit with which the power converter using the reactor with a cooler of an Example is equipped.

  A reactor 200 with a cooler according to an embodiment will be described with reference to the drawings. In FIG. 1, the perspective view of the reactor 200 with a cooler is shown. In the perspective view shown in FIG. 1, the outer shape of the core 3, which is the outer shape of the reactor 200 with a cooler, is drawn by a two-dot chain line, and the core 3 is schematically drawn to be transparent so It is the figure which made structure easy to see. 2 represents a sectional view taken along line II-II in FIG. 1, FIG. 3 represents a sectional view taken along line III-III in FIG. 2, and FIG. 4 represents a sectional view taken along line IV-IV. As shown in FIG. 1, the cooler-equipped reactor 200 includes a coil 2, a cooler 4, a refrigerant supply pipe 5, and a refrigerant discharge pipe 6. A rectangular parallelepiped core 3 is provided which is solidified with a resin containing magnetic particles (hereinafter referred to as a magnetic mixed resin) so as to constitute an outer shell of the reactor 200 with a cooler. The core 3 is hardened so that the magnetic substance mixed resin fills the inside of the coil 2 and covers the outside. As shown in FIGS. 2 and 3, the inside of the coil 2 is filled with an inner core 3 a hardened with a magnetic material mixed resin. As shown in FIGS. 2 and 3, the outer side of the coil 2 in the winding diameter direction (direction perpendicular to the winding axis WL) and the outer side in the winding axis direction are external cores 3b solidified with a magnetic material mixed resin. Covered with. It should be noted that the inner core 3a and the outer core 3b are combined into one lump and are only separated for convenience of explanation.

  The coil 2 will be described. The coil 2 is a coil in which a flat wire 21 made of copper is wound in an edgewise manner. That is, in the coil 2, the flat wire 21 is wound so that the wide side surface of the flat wire 21 is laminated in the direction of the winding axis WL of the coil 2 (hereinafter referred to as the winding axis direction). The width (line width) of the wide side surface of the flat wire 21 is appropriately set according to the electrical characteristics or specifications of the reactor 200 with a cooler. In this embodiment, the coil 2 is wound so as to form a square tube shape with the winding axis WL as the center line of the tube. The coil 2 is provided with lead wires 21a and 21b for electrical connection with an external electronic device. The lead wire 21a extends from one end surface in the winding axis direction of the coil 2 along the winding axis direction. The lead wire 21b wraps around from the other end surface in the winding axis direction of the coil 2 to the side surface in the winding radial direction of the coil 2, and toward the end surface where the lead wire 21a extends. It extends along. That is, the leader lines 21a and 21b extend in parallel toward the same direction.

  The coil 2 is arranged so that one end face in the winding axis direction faces the upper surface of the core 3 (side face in the positive Z-axis direction). In other words, the Z-axis direction in FIG. 1 coincides with the direction of the winding axis WL of the coil 2. Corresponding to this arrangement, the lead lines 21 a and 21 b pass through the top surface of the core 3 and protrude to the outside of the core 3.

  The cooler 4 will be described. The cooler 4 is a rectangular parallelepiped thin in one direction. As shown in FIG. 2, the cooler 4 is disposed such that the wide side surface 4 a faces the one side surface 2 a in the winding radial direction of the coil 2. The cooler 4 is embedded in the core 3 (external core 3b). Specifically, as shown in FIGS. 2 and 3, the wide side surface 4a facing the coil 2 of the cooler 4 and the four side surfaces extending in the thickness direction (Y-axis direction) from the end side of the side surface 4a are: Covered by the outer core 3b. These side surfaces are in close contact with the outer core 3b. On the other hand, in the cooler 4, the side surface 4b located on the opposite side of the side surface 4a is not covered with the outer core 3b. That is, the side surface 4b of the cooler 4 is flush with the rear surface of the core 3 (side surface in the negative Y-axis direction).

  The cooler 4 is made of an insulating resin. This insulating resin is a different type of resin from the magnetic mixed resin that is the material of the core 3. In order to absorb heat from the core 3 by the refrigerant passing through the inside of the cooler 4, it is better that the resin of this insulator is a material having high thermal conductivity. Furthermore, it is preferable that the material has high heat resistance.

  Further, as shown in FIG. 3, wave-shaped heat radiation fins 7 are provided inside the cooler 4. This wave shape is arranged along the short side direction (Z-axis direction) of the cooler 4, and the top of the wave shape is on the inner surface of the wide side wall (side wall having side surfaces 4 a and 4 b) of the cooler 4. In contact. Due to the radiation fins 7, the surface area inside the cooler 4 is enlarged, and the contact area between the refrigerant passing through the inside of the cooler 4 and the surface inside the cooler 4 is enlarged. Therefore, the cooling performance of the cooler 4 is improved.

  The refrigerant supply pipe 5 and the refrigerant discharge pipe 6 will be described. The refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are hollow circular pipes. The refrigerant supply pipe 5 and the refrigerant discharge pipe 6 penetrate the core 3 (external core 3) from the wide side surface 4a facing the coil 2 of the cooler 4 in a direction (Y-axis direction) orthogonal to the side surface 4a. Is growing. In other words, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are orthogonal to the winding axis direction (Z-axis direction) of the coil 2 and from the cooler 4 to the front surface of the core 3 (the side where the cooler 4 is disposed). It is arranged so as to extend toward the opposite side). And the hole is provided in the both ends in the longitudinal direction (X-axis direction) of the side surface 4a of the cooler 4, and the refrigerant | coolant supply pipe | tube 5 and the refrigerant | coolant discharge pipe 6 are extended from the hole. That is, the internal space of the cooler 4 communicates with the internal space of the refrigerant supply pipe 5 and the refrigerant discharge pipe 6. As shown in FIGS. 2 and 4, the outer peripheral surfaces of the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are embedded in the core 3 (outer core 3). The outer peripheral surfaces of the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are in close contact with the outer core 3b. One end 5 a of the refrigerant supply pipe 5 protrudes from the front surface of the core 3, and one end 6 a of the refrigerant discharge pipe 6 also protrudes from the front surface of the core 3. As shown in FIG. 4, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 sandwich the coil 2 when viewed from the direction (Y-axis direction) orthogonal to the wide side surface 4 a of the cooler 4, Is arranged. As shown in FIG. 2, the cooler 4, the refrigerant supply pipe 5, and the refrigerant discharge pipe 6 are arranged so as to surround the three side surfaces 2 a, 2 b, and 2 c of the coil 2 with a square cylindrical shape. That is, the cooler 4 faces one side surface 2 a in the winding radial direction of the coil 2, the refrigerant supply pipe 5 faces the other side surface 2 b in the winding radial direction of the coil 2, and the refrigerant discharge pipe 6 It faces the side surface 2c opposite to the side surface 2b.

  The refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are made of an insulating resin. Preferably, the cooler 4 is made of the same material.

  The refrigerant that passes through the cooler 4, the refrigerant supply pipe 5, and the refrigerant discharge pipe 6 will be described. As indicated by the arrows in FIG. 1, the refrigerant that has flowed from one end 5 a of the refrigerant supply pipe 5 passes through the refrigerant supply pipe 5 and flows into the cooler 4. The refrigerant passes through the inside of the cooler 4 and flows into the refrigerant discharge pipe 6 from a hole provided in the side surface 4a of the cooler 4 to which the refrigerant discharge pipe 6 is connected. The refrigerant flowing into the refrigerant discharge pipe 6 passes through the refrigerant discharge pipe 6 and flows out from one end 6a thereof. The refrigerant is a liquid, for example, water or LLC (Long Life Coolant).

  The cooler 4 is embedded in the core 3 (outer core 3b) and is in close contact with the outer core 3b. Therefore, the heat of the core 3 is transmitted from the side surface of the cooler 4 to the refrigerant passing through the cooler 4 and absorbed by the refrigerant. On the other hand, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are also embedded in the core 3 (external core 3b), and the outer peripheral surfaces of the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are in close contact with the external core 3b. Therefore, the heat of the core 3 is also transmitted from the outer peripheral surfaces of the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 to the refrigerant passing through the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 and is absorbed by the refrigerant. Therefore, the heat of the core 3 is absorbed not only by the cooler 4 but also by the refrigerant supply pipe 5 and the refrigerant discharge pipe 6.

  In the reactor 200 with a cooler of an Example, the magnetic flux which generate | occur | produces from the coil 2 is demonstrated. A closed curve indicated by a thick arrow in FIG. 3 represents the magnetic flux MF generated by the coil 2. Hereinafter, it is assumed that the magnetic flux represented by the thick arrow is generated along the direction of the thick arrow. As shown in FIG. 3, the magnetic flux MF is formed so as to surround the periphery of the cross section along the winding axis direction (Z-axis direction) of the coil 2. However, a core made of a magnetic material mixed resin has a low magnetic permeability and easily leaks a magnetic flux compared to a core made of a lump of magnetic material (for example, ferrite or electromagnetic steel obtained by sintering iron powder). Here, since the cooler 4 is embedded in the core 3 (external core 3b), the place where the cooler 4 is disposed is not filled with the magnetic material mixed resin. Therefore, magnetic flux leaks from the side surface 3c of the outer core 3b that is in close contact with the wide side surface 4a of the cooler 4. Magnetic flux leaking from the side surface 3c of the outer core 3b (hereinafter referred to as leakage magnetic flux) is generated so as to bend from the side surface 3c toward the cooler 4 as indicated by a thick arrow with a reference numeral MF1 in FIG. Therefore, the leakage magnetic flux MF1 passes through the side surface 4a of the cooler 4. It should be noted that the thick line arrow representing the leakage flux MF1 in the figure schematically represents the direction of the leakage flux to help understanding, and is not accurate. The same applies to the subsequent drawings.

  On the other hand, the magnetic flux MF surrounds the periphery of the cross section of the coil 2 when viewed from the direction (Y-axis direction) orthogonal to the wide side surface 4a of the cooler 4 as shown by the closed curve shown by the thick arrow in FIG. Formed. Here, since the refrigerant supply pipe 5 is embedded in the core 3 (outer core 3b), the portion where the refrigerant supply pipe 5 is disposed is not filled with the magnetic substance mixed resin. Therefore, a leakage flux MF2 is generated on the side surface of the outer core 3b that is in close contact with the outer peripheral surface of the refrigerant supply pipe 5. This leakage magnetic flux MF2 passes through the refrigerant supply pipe 5 as shown by the thick arrow in FIG. As shown in FIG. 4, also in the refrigerant discharge pipe 6, the leakage magnetic flux MF <b> 2 passes through the refrigerant discharge pipe 6, similarly to the refrigerant supply pipe 5.

  Generally, when a magnetic flux passes through a conductor such as metal, an eddy current is generated at a location where the magnetic flux has passed. This eddy current causes heat generation. However, the cooler 4 provided in the reactor 200 with the cooler of the embodiment is made of an insulating resin. Therefore, no eddy current is generated in the cooler 4. Therefore, heat generation of the cooler 4 due to eddy current is prevented. This prevents useless heat generation inside the reactor 200 with a cooler, and contributes to the prevention of a decrease in heat radiation performance of the reactor 200 with a cooler.

  On the other hand, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are also made of an insulating resin. Therefore, no eddy current is generated in the refrigerant supply pipe 5 and the refrigerant discharge pipe 6. Therefore, similarly to the cooler 4 described above, heat generation of the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 is prevented. This prevents the useless heat generation inside the reactor 200 with the cooler, similarly to the cooler 4.

  Further, the magnetic flux density of the magnetic flux MF generated from the coil 2 becomes higher as it is closer to the coil 2. According to the above configuration, since no eddy current is generated in the cooler 4, the cooler 4 does not generate heat even in a place where the magnetic flux density is high. In other words, the closer the cooler 4 is to the coil 2, the more the cooling performance can be improved. Moreover, since the cooler 4 can be brought close to the coil 2, the size of the cooler 4 and the coil 2 in the arrangement direction (Y-axis direction) of the reactor 200 with the cooler can be reduced. Therefore, making the cooler 4 made of resin also contributes to reducing the size of the reactor 200 with a cooler.

  Other effects of the configuration of the present embodiment will be described. As described above, the cooler 4, the refrigerant supply pipe 5, and the refrigerant discharge pipe 6 are arranged so as to surround the three side surfaces 2a, 2b, and 2c of the square cylindrical shape of the coil 2 (see FIG. 2). That is, the refrigerant path is configured to surround the three side surfaces of the coil 2. The heat generated from the coil 2 is diffused to the outer core 3b that covers all directions outside the coil 2. Therefore, when the refrigerant passes so as to surround the three side surfaces of the coil 2, the diffusing heat can be efficiently absorbed.

  The manufacturing method of the reactor 200 with a cooler of an Example is demonstrated. FIG. 5 is a schematic view showing a method for manufacturing reactor 200 with a cooler. First, the cooler 4 to which the coil 2 previously wound in the shape of a square cylinder and the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are connected is placed in the lower mold 12. Thereafter, the opening of the lower mold 12 is covered by the upper mold. Note that the upper mold is not shown in FIG. A resin (magnetic mixed resin) containing fluid magnetic particles is filled from an inflow pipe 12a provided in the lower mold 12 at a predetermined temperature and a predetermined pressure. Then, the reactor 200 with a cooler of an Example is formed because a magnetic body mixed resin hardens along the shape of the upper mold | type and the lower mold | type 12. FIG.

  Example in which the coil 2, the cooler 4, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are embedded in the core and the cooler 4, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 are formed integrally with the reactor by the above manufacturing method. The reactor 200 with the cooler is manufactured. By forming the cooler 4 and the reactor integrally, when manufacturing a plurality of reactors with coolers 200, it is easy to manage the variation in distance between the coil 2 embedded in the core 3 and the cooler 4. can do. Similarly, it is possible to easily manage variation in distance between the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 and the coil 2. The variation in distance causes the variation in the heat dissipation performance of the reactor. Therefore, the dispersion | variation in the thermal radiation performance of the reactor 200 with a cooler can be suppressed small by shape | molding integrally by said manufacturing method.

  In addition, the above manufacturing method improves the adhesion between the core 3 and the cooler 4 than making the cooler 4 and the core 3 separately and bonding them later. Therefore, heat transfer between the core 3 and the cooler 4 can be improved by the above manufacturing method.

  With reference to FIG. 6, the modification of the reactor 200 with a cooler of an Example is demonstrated. The reactor 201 with a cooler of a modification is the same structure as the reactor 200 with a cooler of an Example except the shapes of a refrigerant | coolant supply pipe | tube and a refrigerant | coolant discharge pipe differing. Hereinafter, the refrigerant supply pipe 25 and the refrigerant discharge pipe 26 of the reactor 201 with the cooler will be described. FIG. 6 is a cross-sectional view of the reactor 201 with a cooler viewed from the same direction (Y-axis direction) as FIG. The refrigerant supply pipe 25 is a square pipe whose transverse section (cross section orthogonal to the extending direction of the refrigerant supply pipe 25) is a long and narrow rectangle along the winding axis direction (Z-axis direction) of the coil 2. The length in the longitudinal direction (Z-axis direction) of the transverse section of the refrigerant supply pipe 25 is the same as the length in the winding axis direction of the coil 2. Similarly, the refrigerant discharge pipe 26 is also a rectangular tube whose cross section is an elongated rectangle along the winding axis direction of the coil 2, and the length of the cross section in the longitudinal direction is the winding axis direction of the coil 2. Is the same length. As shown in FIG. 6, the wide side surface 25 a of the refrigerant supply pipe 25 is opposed to one side surface 2 b of the rectangular tube shape of the coil 2, and the wide side surface 26 a of the refrigerant discharge pipe 26 is the square of the coil 2. It faces the other cylindrical side surface 2c.

  According to such a structure, the area of the side surface of the refrigerant | coolant supply pipe | tube 25 and the refrigerant | coolant discharge pipe 26 which opposes the side surface of the coil 2 can be expanded compared with the circular tube of a previous Example. Therefore, the heat transmitted from the coil 2 to the core 3 (external core 3b) is efficiently transmitted to the refrigerant supply pipe 25 and the refrigerant discharge pipe 26, and the heat dissipation performance of the reactor with a cooler can be enhanced as compared with the previous embodiment.

  With reference to drawings, the lamination | stacking unit provided with the reactor 200 with a cooler of an Example and a power converter are demonstrated. FIG. 7 is a block diagram of a power system of a power converter 300 including the reactor 200 with a cooler according to the embodiment. The power converter 300 is mounted on the electric vehicle 800. The electric vehicle 800 includes two three-phase AC motors (hereinafter, motors) 83a and 83b. The outputs of the two motors 83a and 83b are combined by the power distribution mechanism 85 and transmitted to the axle 86 (that is, drive wheels).

  The power converter 300 is connected to the battery 81 via the system main relay 82. The power converter 300 includes a voltage converter circuit 91 that boosts the voltage of the battery 81, and two sets of inverter circuits 92a and 92b that convert the boosted DC power into AC. The two sets of inverter circuits 92a and 92b are connected to motors 83a and 83b, respectively. The inverter circuits 92a and 92b may convert the electric power (regenerative electric power) generated by the motors 83a and 83b during braking of the vehicle into direct current. In this case, the converted power is stepped down by the voltage converter circuit 91 and charged to the battery 81.

  The voltage converter circuit 91 includes a series circuit of two switching elements T7 and T8. The voltage converter circuit 91 includes a reactor having one end connected to the midpoint of the series circuit and the other end connected to the input terminal on the high potential side. The reactor 200 with a cooler of an Example is utilized as this reactor. The voltage converter circuit 91 is connected between a filter capacitor 87 connected between an input terminal on the high potential side and an input terminal on the low potential side, and connected between the output side on the high potential side and the output side on the low potential side. And a smoothing capacitor 88 and a diode connected in antiparallel to each switching element. The line on the low potential side is directly connected on the input side and output side of the voltage converter circuit 91, and these are held at the ground potential of the circuit. Here, the circuit in the range of the broken rectangle indicated by the symbol PC7 corresponds to a power card PC7 described later as hardware.

  The voltage converter circuit 300 boosts the voltage of the battery 81 and supplies it to the inverter circuit 92a (92b) (boost operation), and direct-current power input from the inverter circuit 92a (92b) side (generated by the motor 83a or 83b). (Regenerative electric power) to be stepped down and supplied to the battery 81 (step-down operation) can be performed. In the former case, the switching element T8 mainly contributes, and in the latter case, the switching element T7 mainly contributes. Since the voltage converter circuit of FIG. 7 is well known, detailed description thereof is omitted. As described above, in the voltage converter circuit 300, the current may flow from the battery side to the inverter circuit side or from the inverter circuit side to the battery side. It should be noted that for convenience of explanation, the battery-side terminal of the voltage converter circuit 300 is referred to as an input end (input side), and the inverter circuit-side terminal of the voltage converter circuit is referred to as an output end (output side).

  The inverter circuit 92a has a configuration in which three sets of series circuits of two switching elements are connected in parallel (T1 and T4, T2 and T5, T3 and T6). A diode is connected in antiparallel to each switching element. The high potential ends of the three sets of series circuits are connected to the high potential side output ends of the voltage converter circuit 91, and the low potential ends of the three sets of series circuits are connected to the low potential side output ends of the voltage converter circuit 91. Has been. Three-phase alternating current (U-phase, V-phase, W-phase) is output from the midpoint of the three sets of series circuits. Here, each of the series circuits in the range of the broken rectangle indicated by the reference characters PC1, PC2, and PC3 corresponds to power cards PC1, PC2, and PC3, which will be described later as hardware.

  Since the configuration of the inverter circuit 92b is the same as that of the inverter circuit 92a, a specific circuit is not shown in FIG. Similarly to the inverter circuit 92a, the inverter circuit 92b has a configuration in which three sets of series circuits of switching elements are connected in parallel. The hardware modules corresponding to each series circuit are referred to as power cards PC4, PC5, and PC6. Since the inverter circuits 92a and 92b in FIG. 7 are well known, detailed description thereof is omitted.

  The switching elements T1 to T8 are transistors, typically IGBTs (Insulated Gate Bipolar Transistors), but may be other transistors, for example, MOSFETs (Metal Oxide Semiconductor Field Effect Transistors).

  With reference to FIG. 8, the hardware configuration of the stacked unit provided in power converter 300 will be described. In order to efficiently cool the plurality of switching elements, the power converter 300 is formed by stacking the seven power cards PC1 to PC7, the plurality of cooling plates 31, and the reactor 200 with the cooler of the embodiment that accommodate the plurality of switching elements. A stacked unit 400 is provided. FIG. 8 is a plan view seen from a direction perpendicular to the stacking direction of the stacking unit 400. The circuit wiring shown in FIG. 7 can be configured by connecting each terminal provided on each power card and the lead wires 21a and 21b of the reactor 200 with a cooler with a bus bar. In FIG. Note that the illustration is omitted.

  As shown in FIG. 8, each power card PC1 to PC7 has a thin rectangular parallelepiped shape in the stacking direction (Y-axis direction). Each power card is alternately stacked with eight cooling plates 31 having a thin rectangular parallelepiped shape in the stacking direction. Each power card is sandwiched between cooling plates 31 on both sides. The plurality of cooling plates are made of a metal having high thermal conductivity, for example, aluminum, and the inside thereof is a cavity through which the coolant passes. The cooling plate 31 is provided with holes along the laminating direction on both sides in the longitudinal direction, and adjacent cooling plates 31 are connected by connecting pipes 34a and 34b connected to the holes. In the drawing, a refrigerant inflow pipe 32 and a refrigerant outflow pipe 33 are connected to the cooling plate 31 located at the lower end in the stacking direction (Y-axis direction). Here, the connecting pipe 34a and the refrigerant inflow pipe 32 located on the right side in the figure are circular pipes, and the center lines thereof coincide. The connecting pipe 34a and the refrigerant inflow pipe 32 are collectively referred to as a cooling plate supply pipe 36. The cooling plate supply pipe 36 penetrates one end in the longitudinal direction (X-axis direction) of the plurality of cooling plates 31 along the stacking direction (Y-axis direction), and the internal space of the cooling plate supply pipe 36 Is in communication with the internal space of each cooling plate 31. In addition, the connecting pipe 34b and the refrigerant outflow pipe 33 located on the left side in the figure are circular pipes, and the center lines thereof coincide. The connecting pipe 34b and the refrigerant outflow pipe 33 are collectively referred to as a cooling plate discharge pipe 37. The cooling plate discharge pipe 37 penetrates the other end in the longitudinal direction (X-axis direction) of the plurality of cooling plates 31 along the stacking direction (Y-axis direction). Is in communication with the internal space of each cooling plate 31.

  The reactor 200 with a cooler is disposed outside the cooling plate 31 on the side where the refrigerant inflow pipe 32 and the refrigerant outflow pipe 33 are not provided and located at the end in the stacking direction so as to be adjacent to the cooling plate 31. . The refrigerant supply pipe 5 of the reactor 200 with the cooler is connected to the hole provided in the cooling plate 31 located outside, and the refrigerant discharge pipe 6 of the reactor 200 with the cooler is also provided in the cooling plate 31. It is connected to the hole. The refrigerant supply pipe 5 and the cooling plate supply pipe 36 have the same center line, and the refrigerant discharge pipe 6 and the cooling plate discharge pipe 37 have the same center line. The internal space of the refrigerant supply pipe 5 and the internal space of the cooling plate supply pipe 36 communicate with each other, and the internal space of the refrigerant discharge pipe 6 and the internal space of the cooling plate discharge pipe 37 communicate with each other. Therefore, the refrigerant flowing in from the refrigerant inflow pipe 32 is distributed to the plurality of cooling plates 31 and the cooler 4 of the reactor 200 with the cooler by the connecting pipe 34 a and the refrigerant supply pipe 5. The refrigerant absorbs the heat of the PC7 and the core 3 from each adjacent power card PC1 while passing through the inside of each cooling plate 31 and the cooler 4, and the refrigerant outflow pipe 33 through the other connection pipe 34b and the refrigerant discharge pipe 6. More outflow. As shown in FIG. 8, the reactor 200 with the cooler is located downstream of the plurality of cooling plates 31 with respect to the flow of the refrigerant.

  In the reactor 200 with a cooler, the side surface 3d of the core 3 opposite to the cooler 4 with the coil 2 interposed therebetween is in contact with the side surface 31a of the cooling plate 31 in the stacking direction via the heat dissipation sheet 35. According to such a configuration, the heat of the core 3 can be absorbed also from the side surface 3 d of the core 3. Therefore, the reactor 200 with a cooler can be cooled more efficiently.

  Hereinafter, points to be noted regarding the technology shown in the embodiments will be described. The shape of the radiation fin provided inside the cooler may be a shape other than the wave shape as shown in FIG. For example, a comb-shaped heat radiation fin may be used. In this case, the comb shape is arranged along the short side direction (Z-axis direction) of the cooler 4, and is preferably provided at least on the inner surface of the side wall facing the coil 2 of the cooler 4.

  In the embodiment, the side surface 4b of the cooler 4 is flush with the rear surface of the core 3. However, the side surface 4b of the cooler 4 may be located inside or outside the rear surface of the core 3. Furthermore, the entire surface of the cooler 4 may be covered with the core 3 (external core 3b). It suffices that at least the side surface 4a facing the coil 2 of the cooler 4 is covered with the core 3 (external core 3b).

  Moreover, although the number of the coils 2 in the embodiment is one, there may be a plurality. For example, it may be a pair of coils in which two coils are connected in series and arranged in parallel in the winding radial direction. In addition, the coil 2 of the embodiment is an edgewise winding coil in which the flat wire 21 is wound, but may be a coil in which a round wire is wound.

  Further, the arrangement of the reactor with a cooler in the stacked unit is not limited to the position shown in FIG. For example, the reactor with a cooler may be located upstream of the cooling plate with respect to the flow of the refrigerant. That is, the reactor 200 with a cooler may be disposed adjacent to the cooling plate 31 provided with the refrigerant inflow pipe 32 and the refrigerant outflow pipe 33 in FIG. In this case, the refrigerant supply pipe 5 and the refrigerant discharge pipe 6 extend to the outside of the core 3 so as to pass through the cooler 4, and the refrigerant flows into the cooler 4 and the cooling plate 31 from the extended portion. Will be distributed. Since the reactor 200 with a cooler is positioned upstream of the flow of the refrigerant, the reactor 200 with a cooler can be cooled in preference to each power card.

  Further, the cooling plate of the stacked unit may be made of the same insulating resin as the cooler of the reactor with the cooler.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Coil 3: Core 4: Cooler 5: Refrigerant supply pipe 6: Refrigerant discharge pipe 7: Heat radiation fin 12: Lower mold 21: Rectangular wire 31: Cooling plate 32: Inflow pipe 33: Outflow pipe 34a, 34b: Connecting pipe 35: Heat radiation sheet 36: Cooling plate supply pipe 37: Cooling plate discharge pipe 81: Battery 82: System main relay 83a, 83b: Motor 85: Power distribution mechanism 86: Axle 91: Voltage converter circuit 92a, 92b: Inverter circuit 200: Reactor with cooler 300: Power converter 400: Laminated unit MF: Magnetic flux MF1, MF2: Leakage magnetic flux WL: Winding axes T1, T2, T3, T4, T5, T6, T7, T8: Switching elements PC1, PC2 , PC3, PC4, PC5, PC6, PC7, PC8: Power card

Claims (7)

Coils,
A core filled with a resin containing magnetic particles so as to fill the inside of the coil and cover the outside;
A cooler embedded in the core so as to face the coil;
With
A reactor with a cooler, wherein the cooler is made of an insulating resin. A refrigerant supply pipe and a refrigerant discharge pipe extend from the surface of the cooler facing the coil so as to penetrate the core,
The refrigerant supply pipe and the refrigerant discharge pipe are arranged on both sides of the coil when viewed from a direction orthogonal to the facing surface.
The reactor with a cooler of Claim 1 characterized by the above-mentioned. The coil has a rectangular tube shape,
The reactor with a cooler according to claim 2, wherein the cooler, the coolant supply pipe, and the coolant discharge pipe are arranged so as to surround three side surfaces of the rectangular tube shape of the coil.   The reactor with a cooler according to claim 2 or 3, wherein the refrigerant supply pipe and the refrigerant discharge pipe are made of an insulating resin.   The reactor with a cooler according to any one of claims 1 to 4, wherein a radiation fin is provided inside the cooler. It is a manufacturing method of the reactor with a cooler according to any one of claims 1 to 5,
Placing the coil and the cooler in a mold;
Filling the mold with a fluid resin containing magnetic particles;
The manufacturing method of the reactor with a cooler characterized by including. The reactor with a cooler according to any one of claims 2 to 4,
Multiple cooling plates;
A plurality of power cards containing switching elements;
With
The reactor, the plurality of cooling plates, and the plurality of power cards are laminated,
A cooling plate supply pipe and a cooling plate discharge pipe pass through the plurality of cooling plates along the stacking direction, and the cooling plate supply pipe is connected so that a center line coincides with the refrigerant supply pipe. And the cooling plate discharge pipe is connected so that the center line of the refrigerant discharge pipe coincides,
One of the plurality of cooling plates is in contact with the side surface of the reactor opposite to the cooler,
A laminated unit characterized by that.

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