JP4506668B2 - Reactor cooling structure and electrical equipment unit - Google Patents

Description

  The present invention relates to a reactor cooling structure and an electric equipment unit, and more particularly to a reactor cooling structure including a core and a coil, and an electric equipment unit including the reactor.

A reactor having a reactor core and a reactor coil has been conventionally known.
For example, Japanese Patent Laying-Open No. 2004-95570 (Patent Document 1) discloses a structure in which a reactor is fixed to a pedestal with a holding portion.

  Japanese Patent Laying-Open No. 2004-193322 (Patent Document 2) discloses a structure in which a reactor, which is an electronic component, is accommodated in a case, and resin is poured into the case to enclose the reactor.

In JP 2005-73392 A (Patent Document 3), a protruding portion having a shape capable of storing a reactor is provided on the inner wall of the PCU case, and the reactor stored so as to be surrounded by the protruding portion is used as a case. A structure with means for adhering is disclosed.
JP 2004-95570 A JP 2004-193322 A JP 2005-73392 A

  In the structures described in Patent Documents 1 to 3, it is necessary to form a pedestal or storage unit having a complicated structure for fixing the reactor. Thereby, a reactor apparatus will enlarge and cost will increase.

  Moreover, when the resin part is formed around the reactor and the thickness of a part of the resin part is excessively large, the heat transfer efficiency of the part decreases. In addition, if the thickness of the resin part differs greatly between the reactor core and the cooler and between the reactor coil and the cooler, the amount of creep deformation of the resin part varies, and the resin part and the cooler There may be gaps. As a result, there is a concern that the cooling performance of the reactor is lowered. For example, when a reactor is placed on a planar heat transfer surface, the distance between the reactor core and the heat transfer surface increases, and the thickness of the resin portion located below the reactor core increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to reduce the size and cost of the reactor device and to suppress a decrease in the cooling efficiency of the reactor. It is an object to provide a reactor cooling structure and an electric equipment unit having the structure.

  In one aspect, the reactor cooling structure according to the present invention includes a reactor, a cooler that cools the reactor, a resin portion that is provided around the reactor, and a fixing unit that fixes the resin portion to the cooler. The reactor has a reactor core and a reactor coil wound around the reactor core, and is provided so as to protrude from the reactor core toward the cooler, and has a higher heat transfer rate than the resin part. Is further provided.

  According to the said structure, since a reactor can be fixed to a cooler via a resin part, the reactor apparatus by which size reduction and cost reduction were achieved is obtained. Here, by providing the heat transfer part between the reactor core and the cooler, it is possible to prevent an excessive increase in the thickness of a part of the resin part. Therefore, the efficiency of heat transfer between the reactor core and the cooler can be improved. As a result, a decrease in the cooling efficiency of the reactor can be suppressed.

  In another aspect, the reactor cooling structure according to the present invention includes a reactor, a cooler that cools the reactor, a resin portion that is provided around the reactor, and a fixing unit that fixes the resin portion to the cooler. The reactor includes a reactor core and a reactor coil wound around the reactor core, and the resin portion includes a first portion located between the reactor core and the cooler, and the reactor coil and the cooler. A second portion located between them, and the thicknesses of the first and second portions in the resin portion are substantially equal to each other.

  Also in this aspect, since the reactor can be fixed to the cooler via the resin portion, a pedestal and a case for fixing the reactor can be omitted. Therefore, a reactor device that is reduced in size and cost can be obtained. Here, by making the thicknesses of the first and second portions substantially equal, it is possible to suppress the heat transfer efficiency from one of the reactor core and the reactor coil from being excessively decreased and the cooling efficiency of the reactor from being decreased. it can.

  In the reactor cooling structure, preferably, the heat transfer section and the reactor core are integrally formed. As one example, the reactor core is formed of a dust core.

Thereby, the said heat-transfer part can be obtained, suppressing the increase in cost.
In the reactor cooling structure, preferably, the fixing means includes a pressing member that presses the resin portion toward the cooler.

  In the above configuration, when the resin portion creep-deforms due to the pressing force from the pressing member, it is possible to suppress the difference in deformation amount between the first and second portions of the resin portion. It can suppress that a clearance gap generate | occur | produces between them and the cooling efficiency of a reactor falls.

  The electric equipment unit according to the present invention includes an inverter and the reactor cooling structure described above. And a reactor is provided in the electric power supply path | route to an inverter.

  ADVANTAGE OF THE INVENTION According to this invention, while aiming at size reduction and cost reduction of a reactor apparatus, it can suppress that the cooling efficiency of a reactor falls.

  Hereinafter, embodiments of a reactor cooling structure and an electric equipment unit according to the present invention will be described. Note that the same or corresponding portions are denoted by the same reference numerals, and the description thereof may not be repeated.

  FIG. 1 is a diagram schematically showing an example of the structure of a drive unit including a reactor cooling structure according to Embodiments 1 and 2 of the present invention. In the example shown in FIG. 1, the drive unit 1 is a drive unit mounted on a hybrid vehicle, and includes a motor generator 100, a housing 200, a speed reduction mechanism 300, a differential mechanism 400, a drive shaft receiving portion 500, And a terminal block 600.

  The motor generator 100 is a rotating electric machine having a function as an electric motor or a generator. The motor generator 100 is a rotary shaft 110 that is rotatably attached to the housing 200 via a bearing 120, a rotor 130 that is attached to the rotary shaft 110, and a stator. 140.

  The rotor 130 includes, for example, a rotor core configured by laminating plate-like magnetic bodies such as iron or an iron alloy, and a permanent magnet embedded in the rotor core. For example, the permanent magnets are arranged at substantially equal intervals in the vicinity of the outer periphery of the rotor core. In addition, you may comprise a rotor core with a powder magnetic core.

  The stator 140 includes a ring-shaped stator core 141, a stator coil 142 wound around the stator core 141, and a bus bar 143 connected to the stator coil 142. The bus bar 143 is connected to a PCU (Power Control Unit) 700 through a terminal block 600 provided in the housing 200 and a power supply cable 700A. PCU 700 is connected to battery 800 via power supply cable 800A. Thereby, battery 800 and stator coil 142 are electrically connected.

  The stator core 141 is configured by, for example, laminating plate-like magnetic bodies such as iron or iron alloy. A plurality of teeth portions (not shown) and slot portions (not shown) as recesses formed between the teeth portions are formed on the inner peripheral surface of the stator core 141. The slot portion is provided so as to open to the inner peripheral side of the stator core 141. In addition, you may comprise the stator core 141 by a dust core.

  Stator coil 142 including three winding phases, U-phase, V-phase, and W-phase, is wound around the tooth portion so as to fit into the slot portion. The U phase, V phase, and W phase of the stator coil 142 are wound so as to deviate from each other on the circumference. Bus bar 143 includes a U phase, a V phase, and a W phase corresponding to the U phase, V phase, and W phase of stator coil 142, respectively.

  The feeding cable 700A is a three-phase cable including a U-phase cable, a V-phase cable, and a W-phase cable. U-phase, V-phase, and W-phase of bus bar 143 are connected to U-phase cable, V-phase cable, and W-phase cable in power supply cable 700A, respectively.

  The power output from the motor generator 100 is transmitted from the speed reduction mechanism 300 to the drive shaft receiving portion 500 via the differential mechanism 400. The driving force transmitted to the drive shaft receiving portion 500 is transmitted as a rotational force to a wheel (not shown) via a drive shaft (not shown), thereby causing the vehicle to travel.

  On the other hand, during regenerative braking of the hybrid vehicle, the wheels are rotated by the inertial force of the vehicle body. Motor generator 100 is driven via drive shaft receiving portion 500, differential mechanism 400 and reduction mechanism 300 by the rotational force from the wheels. At this time, the motor generator 100 operates as a generator. Electric power generated by motor generator 100 is stored in battery 800 via an inverter in PCU 700.

  The drive unit 1 is provided with a resolver (not shown) having a resolver rotor and a resolver stator. The resolver rotor is connected to the rotating shaft 110 of the motor generator 100. The resolver stator has a resolver stator core and a resolver stator coil wound around the core. The rotational angle of the rotor 130 of the motor generator 100 is detected by the resolver. The detected rotation angle is transmitted to the PCU 700. PCU 700 generates a drive signal for driving motor generator 100 using the detected rotation angle of rotor 130 and a torque command value from an external ECU (Electrical Control Unit), and uses the generated drive signal as a motor. Output to the generator 100.

  FIG. 2 is a circuit diagram showing a configuration of a main part of PCU 700. Referring to FIG. 2, PCU 700 includes a converter 710, an inverter 720, a control device 730, capacitors C1 and C2, power supply lines PL1 to PL3, and output lines 740U, 740V, and 740W. Converter 710 is connected between battery 800 and inverter 720, and inverter 720 is connected to motor generator 100 via output lines 740U, 740V, and 740W.

  Battery 800 connected to converter 710 is, for example, a secondary battery such as nickel metal hydride or lithium ion. Battery 800 supplies the generated DC voltage to converter 710 and is charged by the DC voltage received from converter 710.

  Converter 710 includes power transistors Q1 and Q2, diodes D1 and D2, and a reactor L. Power transistors Q1, Q2 are connected in series between power supply lines PL2, PL3, and receive a control signal from control device 730 as a base. Diodes D1 and D2 are connected between the collector and emitter of power transistors Q1 and Q2, respectively, so that current flows from the emitter side to the collector side of power transistors Q1 and Q2. Reactor L has one end connected to power supply line PL1 connected to the positive electrode of battery 800, and the other end connected to a connection point between power transistors Q1 and Q2.

  Converter 710 boosts the DC voltage received from battery 800 using reactor L, and supplies the boosted boosted voltage to power supply line PL2. Converter 710 steps down the DC voltage received from inverter 720 and charges battery 800.

  Inverter 720 includes a U-phase arm 750U, a V-phase arm 750V, and a W-phase arm 750W. Each phase arm is connected in parallel between power supply lines PL2 and PL3. U-phase arm 750U includes power transistors Q3 and Q4 connected in series, V-phase arm 750V includes power transistors Q5 and Q6 connected in series, and W-phase arm 750W includes power connected in series. It consists of transistors Q7 and Q8. Diodes D3 to D8 are respectively connected between the collector and emitter of power transistors Q3 to Q8 so that current flows from the emitter side to the collector side of power transistors Q3 to Q8. The connection point of each power transistor in each phase arm is connected to the anti-neutral point side of each phase coil of motor generator 100 via output lines 740U, 740V, and 740W.

  Inverter 720 converts a DC voltage received from power supply line PL <b> 2 into an AC voltage based on a control signal from control device 730, and outputs the AC voltage to motor generator 100. Inverter 720 rectifies the AC voltage generated by motor generator 100 into a DC voltage and supplies it to power supply line PL2.

  Capacitor C1 is connected between power supply lines PL1 and PL3, and smoothes the voltage level of power supply line PL1. Capacitor C2 is connected between power supply lines PL2 and PL3, and smoothes the voltage level of power supply line PL2.

  Control device 730 calculates each phase coil voltage of motor generator 100 based on the rotation angle of the rotor of motor generator 100, the motor torque command value, each phase current value of motor generator 100, and the input voltage of inverter 720, Based on the calculation result, a PWM (Pulse Width Modulation) signal for turning on / off the power transistors Q3 to Q8 is generated and output to the inverter 720.

  Control device 730 calculates the duty ratio of power transistors Q1 and Q2 for optimizing the input voltage of inverter 720 based on the motor torque command value and the motor rotation speed described above, and power based on the calculation result. A PWM signal for turning on / off the transistors Q 1 and Q 2 is generated and output to the converter 710.

  Further, control device 730 controls switching operations of power transistors Q <b> 1 to Q <b> 8 in converter 710 and inverter 720 in order to charge battery 800 by converting AC power generated by motor generator 100 into DC power.

  In PCU 700, converter 710 boosts a DC voltage received from battery 800 based on a control signal from control device 730, and supplies the boosted voltage to power supply line PL2. Inverter 720 receives the DC voltage smoothed by capacitor C <b> 2 from power supply line PL <b> 2, converts the received DC voltage into an AC voltage, and outputs the AC voltage to motor generator 100.

  Inverter 720 converts the AC voltage generated by the regenerative operation of motor generator 100 into a DC voltage and outputs the DC voltage to power supply line PL2. Converter 710 receives the DC voltage smoothed by capacitor C2 from power supply line PL2, and steps down the received DC voltage to charge battery 800.

  During operation of the PCU 700, the reactor L generates heat. Therefore, it is necessary to provide a cooling structure for the reactor L.

  FIG. 3 is a diagram showing the configuration of the reactor cooling structure according to the first and second embodiments. Referring to FIG. 3, reactor L is mounted on cooler 2. In other words, the cooler 2 has a mounting surface for the reactor L.

  A cooling medium such as LLC (Long Life Coolant) flows in the cooler 2. The cooling medium flowing out of the cooler 2 is sent to the radiator 21 and cooled. Then, the cooling medium flows into the cooler 2 again. As described above, cooling of the reactor L mounted on the cooler 2 is promoted. The coolant is circulated by the water pump 22. Moreover, a cooling water, an antifreeze, etc. may be used as a cooling medium.

  When the reactor L is fixed on the cooler, by providing a pedestal and a case for fixing the reactor L, the reactor device is increased in size and cost is increased.

  On the other hand, the reactor cooling structure according to the first and second embodiments omits a pedestal and a case for fixing the reactor, as will be described later. As a result, a reactor device that is reduced in size and cost can be obtained.

(Embodiment 1)
FIG. 4 is a cross-sectional view showing the reactor cooling structure according to the first embodiment. Referring to FIG. 4, the reactor cooling structure according to the present embodiment includes a reactor L including a reactor core L1 and a reactor coil L2, a cooler 2, and a resin portion 3 formed around the reactor, The heat transfer part 4 provided so that it may protrude toward the cooler 2 from the reactor rear L1 is comprised.

  The reactor core L1 made of metal is typically composed of a dust core, but may be composed of laminated steel plates. For example, an epoxy resin can be used as the resin portion 3. Moreover, the heat-transfer part 4 is comprised with metals, such as aluminum, for example. The heat transfer unit 4 has a higher heat transfer coefficient than the resin unit 3. The heat transfer section 4 may be formed separately from the reactor core L1, or may be formed integrally with the reactor core L1. For example, the reactor core L1 and the heat transfer section 4 can be integrally formed with a dust core.

  The bolt 5 fixes the resin part 3 to the cooler 2. In other words, the reactor L is fixed to the cooler 2 by the bolt 5 via the oil portion 3. By doing in this way, the base and case for fixing the reactor L are omissible. Therefore, a reactor device that is reduced in size and cost can be obtained.

  The resin portion 3 has a first portion 31 located below the reactor core L1 and a second portion 32 located below the reactor coil L2. In the present embodiment, the thickness (t) of the first and second portions 31 and 32 is substantially equal.

  FIG. 7 is a cross-sectional view showing a reactor cooling structure according to a comparative example. Referring to FIG. 7, heat transfer unit 4 is not provided in this comparative example. Accordingly, the thickness of the first portion 31 of the resin portion 3 located below the reactor core L1 is larger than the thickness of the second portion 32 of the resin portion 3 located below the reactor coil L2. As a result, there is a concern that the heat dissipation from the reactor core L1 is reduced. Further, since the thicknesses of the first and second portions 31 and 32 of the resin part 3 are greatly different, the difference in the amount of creep deformation between the first and second parts 31 and 32 becomes large, and the cooler 2 and the resin part 3 A gap is generated between the two. As a result, there is a concern that the cooling performance of the reactor L is lowered. The difference in the amount of creep deformation between the first and second portions 31 and 32 is caused by the difference in coefficient of linear expansion between the metal and the resin.

  On the other hand, in the reactor cooling structure according to the present embodiment, the heat transfer coefficient is higher than that of the resin portion 3 between the portion of the reactor core L1 where the reactor coil L2 is not wound and the cooler 2. A metal heat transfer section 4 is provided, and the gap between the reactor core L1 and the cooler 2 and the gap between the reactor coil L2 and the cooler 2 are made substantially equal. By doing in this way, the heat dissipation from the reactor core L1 improves. Also, by making the thicknesses of the first and second portions 31 and 32 equal, a difference in the amount of creep deformation between the first and second portions 31 and 32 occurs, and a gap is formed between the cooler 2 and the resin portion 3. It is possible to suppress the occurrence. As a result, a decrease in the cooling performance of the reactor L can be suppressed.

  In the example of FIG. 4, by providing the heat transfer section 4, the first and second portions 31 and 32 of the resin portion 3 have the same thickness. The thickness of the portion 32 may be larger, or the thickness of the second portion 32 may be larger than the thickness of the first portion 31. Even in such a case, if the difference between the thicknesses of the first and second portions 31 and 32 is reduced by providing the heat transfer section 4, the same effects as described above can be obtained.

  The above contents are summarized as follows. That is, the reactor cooling structure according to the present embodiment includes a reactor L, a cooler 2 that cools the reactor L, a resin portion 3 provided around the reactor L, and the resin portion 3 fixed to the cooler 2. And a bolt 5 as “fixing means”. Here, the reactor L includes a reactor core L1 and a reactor coil L2 wound around the reactor core L1. The resin portion 3 includes a first portion 31 located between the reactor core L1 and the cooler 2, and a second portion 32 located between the reactor coil L2 and the cooler 2, The thicknesses (t) of the first and second portions 31 and 32 are substantially equal to each other.

  The reactor cooling structure according to the present embodiment further includes a heat transfer section 4 provided so as to protrude from the reactor core L1 toward the cooler 2 and having a higher heat transfer coefficient than the resin section 3. .

  According to the reactor cooling structure according to the present embodiment, it is possible to reduce the size and cost of the reactor device, and to suppress the cooling efficiency of the reactor L from being lowered.

  PCU 700 as an “electrical device unit” according to the present embodiment includes inverter 720 and the reactor L cooling structure described above. Reactor L is provided in the power supply path to inverter 720.

(Embodiment 2)
FIG. 5 is a cross-sectional view showing a reactor cooling structure according to the second embodiment. FIG. 6 is a view of the cooling structure shown in FIG. 5 as viewed from the direction of the arrow VI. 5 and 6, the reactor cooling structure according to the present embodiment is a modification of the reactor cooling structure according to the first embodiment, and fixes resin portion 3 to cooler 2. It is characterized in that the leaf spring 6 and the bolt 7 are used as the “fixing means”. Since other matters are the same as in the first embodiment, detailed description will not be repeated.

  As shown in FIGS. 5 and 6, the leaf spring 6 is provided so as to overlap the resin portion 3. The cooler 2 is provided with a protruding portion 2A. Then, both ends of the leaf spring 6 are fixed to the protruding portion 2 </ b> A by bolts 7. Thereby, the resin part 3 is pressed toward the cooler 2, and the reactor L is fixed. That is, the leaf spring 6 is a “pressing member” that presses the resin portion 3 toward the cooler 2.

  As with the first embodiment, the reactor cooling structure according to the present embodiment can reduce the size and cost of the reactor device, and can also prevent the cooling efficiency of the reactor L from decreasing.

  Further, when the resin portion 3 undergoes creep deformation due to the pressing force from the leaf spring 6, the deformation amounts of the first and second portions 31 and 32 of the resin portion 3 are substantially the same, and therefore the resin portion 3 and the cooler 2 It can suppress that a clearance gap generate | occur | produces between them and the cooling efficiency of a reactor falls.

  Although the embodiments of the present invention have been described above, it is planned from the beginning to appropriately combine the characteristic portions of the respective embodiments described above. In addition, it should be considered that the embodiment disclosed this time is illustrative and not restrictive in all respects. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows schematically an example of the structure of the drive unit containing the cooling structure of the reactor which concerns on Embodiment 1, 2 of this invention. It is a circuit diagram which shows the structure of the principal part of PCU shown by FIG. It is the figure which showed the whole structure of the cooling structure of the reactor which concerns on Embodiment 1,2. It is sectional drawing which shows the cooling structure of the reactor which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the cooling structure of the reactor which concerns on Embodiment 2 of this invention. It is the figure which looked at the cooling structure shown in FIG. 5 from the direction of arrow VI. It is sectional drawing which shows the cooling structure of the reactor which concerns on a comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Drive unit, 2 cooler, 2A protrusion part, 3 resin part, 4 heat-transfer part, 5,7 bolt, 6 leaf | plate spring, 21 radiator, 22 water pump, 31 1st part (resin part), 32 2nd part (Resin part), 100 motor generator, 110 rotating shaft, 120 bearing, 130 rotor, 140 stator, 141 stator core, 142 stator coil, 143 bus bar, 200 housing, 300 speed reduction mechanism, 400 differential mechanism, 500 drive shaft receiving part, 600 Terminal block, 700 PCU, 700A, 800A feeding cable, 710 converter, 720 inverter, 730 controller, 740U, 740V, 740W output line, 750U U-phase arm, 750V V-phase arm, 750W W-phase arm, 80 Battery, C1, C2 capacitor, D1 to D8 diode, L reactor, L1 reactor core, L2 reactor coils, PL1, PL2, PL3 power line, Q1 to Q8 power transistor.

Claims (6)

Reactor,
A cooler for cooling the reactor;
A resin portion provided around the reactor;
Fixing means for fixing the resin part to the cooler;
The reactor has a reactor core and a reactor coil wound around the reactor core,
A reactor cooling structure, further comprising a heat transfer portion provided so as to protrude from the reactor core toward the cooler and having a heat transfer coefficient higher than that of the resin portion.   The reactor cooling structure according to claim 1, wherein the heat transfer section and the reactor core are integrally formed. Reactor,
A cooler for cooling the reactor;
A resin portion provided around the reactor;
Fixing means for fixing the resin part to the cooler;
The reactor has a reactor core and a reactor coil wound around the reactor core,
The resin part has a first part located between the reactor core and the cooler, and a second part located between the reactor coil and the cooler,
A reactor cooling structure in which the first and second portions of the resin portion have substantially the same thickness.   The reactor cooling structure according to any one of claims 1 to 3, wherein the fixing means includes a pressing member that presses the resin portion toward the cooler.   The reactor cooling structure according to claim 1, wherein the reactor core is formed of a dust core. An inverter;
The reactor cooling structure according to any one of claims 1 to 5,
The reactor is an electrical device unit provided in a power supply path to the inverter.

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