JP2017069371A - Discharge resistance device with cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge resistance device with a cooler which allows for compaction and weight saving, while ensuring reliable cooling of a discharge resistor.SOLUTION: In a discharge resistance device with a cooler having an insulating layer composed of ceramics, a first resistor and a second resistor formed side-by-side on one surface of the insulating layer, a metal layer and a cooler laminated, in order, on the other surface of the insulating layer, the metal layer and the cooler are composed of Al or an Al alloy, the cooler has a heat dissipation region, and a heat absorption region having a volume larger than that of the heat dissipation region, and a surface area smaller than that of the heat dissipation region. The first resistor is a discharge resistor capable of discharging the applied voltage in a shorter time than the second resistor. The first resistor is formed at a position overlapping the heat absorption region, and the second resistor is formed at a position overlapping the heat dissipation region.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a discharge resistance device with a cooler capable of optimizing cooling efficiency in accordance with discharge characteristics of a resistor.

In recent years, vehicles equipped with a high-voltage DC power source typified by a hybrid vehicle and a fuel cell vehicle are rapidly spreading.
A vehicle equipped with such a high-voltage DC power supply uses a high-voltage DC power supply having a voltage lower than the motor drive voltage mainly from the viewpoint of safety. A boost converter / inverter circuit system is mainly employed in which the output voltage of the high-voltage DC power source is boosted by a boost converter (up converter) and applied to an inverter for driving a motor.

  Such a boost converter / inverter circuit is configured by connecting a boost converter that boosts the voltage of a high-voltage DC power supply and an inverter that converts the boost DC voltage into an AC voltage and applies the AC voltage to an AC rotating electrical machine (for example, , See Patent Document 1).

  In a boost converter / inverter circuit, a smoothing capacitor for a converter is connected between a pair of input terminals of the boost converter, and a smoothing capacitor for an inverter is connected between a pair of input terminals of the inverter. These smoothing capacitors are capacitors for reducing pulsating current (ripple) in the DC waveform generated by AC / DC conversion, and the smoothing capacitor for the converter is close to the switching element of the boost converter to reduce the switching surge voltage, Further, the smoothing capacitor for the inverter is arranged in the vicinity of the switching element of the inverter.

  In the boost converter / inverter circuit, a discharge resistance element is connected in parallel with the smoothing capacitor for the inverter. The discharge resistance element includes a normal discharge resistance element that discharges between the pair of input terminals of the inverter when the motor is stopped, and a pair of inverters for ensuring safety in the event of any abnormality in the vehicle, such as a collision. An emergency discharge resistance element (short-time discharge resistance element) that discharges between input terminals in a short time is connected in parallel.

  The short-time discharge resistor element is used to convert the smoothing capacitor for the converter and the converter when the power supply from the high-voltage DC power supply to the boost converter / inverter circuit is interrupted due to the disconnection of the power cable between the high-voltage DC power supply and the boost converter. The smoothing capacitor for the inverter is discharged in a short time (for example, within several minutes) to improve electrical safety. That is, the short-time discharge resistance element directly discharges the smoothing capacitor for the inverter and discharges the smoothing capacitor for the converter through a diode built in the boost converter.

JP 2005-253276 A

  Conventionally, a discharge resistance device equipped with both a normal discharge resistance element incorporated in an inverter and the like and a short-time discharge resistance element can sufficiently cool a short-time discharge resistance element that releases a large amount of heat in a short time. A heat capacity cooler was used. For this reason, the size of the cooler has been increased, which has hindered the downsizing of the discharge resistance device.

  The present invention has been made in view of the above-described circumstances, and is equipped with a cooler capable of reducing the size and weight of a discharge resistance device provided with a cooler and capable of reliably cooling the discharge resistor. An object is to provide a discharge resistance device.

  In order to solve the above problems, a discharge resistor device with a cooler according to the present invention includes an insulating layer made of ceramics, and a first resistor and a second resistor formed side by side on one surface side of the insulating layer. And a discharge resistance device with a cooler having a metal layer and a cooler sequentially laminated on the other surface side of the insulating layer, wherein the metal layer and the cooler are made of Al or an Al alloy, and the cooling The vessel has a heat dissipation region and a heat absorption region having a volume larger than that of the heat dissipation region and a small surface area, and the first resistor applies the applied voltage for a short time than the second resistor. The first resistor is formed at a position that overlaps the heat absorption region, and the second resistor is formed at a position that overlaps the heat dissipation region. And

According to the discharge resistor device with a cooler having such a configuration, the cooler is provided with a heat dissipation region and a heat absorption region in accordance with the heat generation characteristics of the first resistor and the second resistor having different discharge times. By forming, the first resistor and the second resistor can be reliably cooled, and the discharge resistor device with a cooler can be reduced in size and weight.
That is, for the first resistor with rapid heat dissipation due to short-time discharge, it is formed at a position overlapping the heat absorption region of the cooler, so that the heat due to the rapid temperature rise of the first resistor has a large heat capacity. In the endothermic region, heat can be absorbed quickly (heat transfer), and the first resistor can be cooled in a short time. On the other hand, for the second resistor with slow heat dissipation due to a relatively long discharge, the second resistor is in contact with the refrigerant with a large surface area by being formed at a position overlapping the heat dissipation region of the cooler. Cooling can be ensured in the heat dissipation area.
And the heat absorption area that overlaps the formation position of the first resistor has a smaller surface area than the heat dissipation area and is formed in a block shape (lumb shape) with a large volume, so that fins and the like that require a large surface area for the entire cooler are formed. Compared with the case where it forms, the discharge resistance apparatus with a cooler which is small and lightweight can be implement | achieved. Normally, in order to cool the large heat generated by the first resistor, the first resistor needs to have a large area or a cooler with a thick top plate. If the heat radiating fin region for the second resistor is added, the size of the device is further increased.

The insulating layer and the metal layer, and the metal layer and the cooler are directly bonded to each other, whereby the insulating layer and the cooler are firmly bonded via the metal layer. Even if stress occurs on the joint surfaces due to the difference in thermal expansion coefficient, peeling at the joint portion can be reliably prevented.

A heat conductor containing Cu or a Cu alloy is further formed in a part of the cooler, and the cooler and the heat conductor, and the metal layer and the heat conductor are joined by solid diffusion bonding, respectively. It is characterized by.
Thereby, the further improvement of the cooling characteristic by the improvement in the thermal conductivity between the first resistor or the second resistor and the cooler can be realized, and the cooler and the heat conductor, and The metal layer and the heat conductor can be firmly bonded.

In the heat radiation area, a flow path for circulating a refrigerant is formed.
Thereby, the heat dissipation efficiency in the heat dissipation area of the cooler can be increased, and the second resistor can be efficiently cooled even with a small surface area.

The insulating layer and the metal layer are bonded using an Al—Si brazing material.
By using an Al-Si brazing material for direct bonding between the insulating layer and the metal layer, the diffusibility of the brazing material is enhanced at each bonding surface of the insulating layer and the metal layer, and the insulating layer and the metal made of different materials from each other. It becomes possible to join the layers very strongly and directly.

The metal layer has a thickness of 0.6 mm or more and 2.5 mm or less.
By forming the metal layer in such a thickness range, thermal stress generated in the insulating layer can be effectively absorbed by the metal layer, and cracks and cracks can be prevented from occurring in the insulating layer.

  ADVANTAGE OF THE INVENTION According to this invention, the discharge resistance apparatus provided with the cooler which enables space saving of the discharge resistance apparatus provided with the cooler, and can perform reliable cooling of a discharge resistor can be provided.

It is sectional drawing which shows the discharge resistance apparatus with a cooler of 1st embodiment. It is sectional drawing which shows the discharge resistance apparatus with a cooler of 2nd embodiment. It is sectional drawing which shows the discharge resistance apparatus with a cooler of 3rd embodiment. It is a schematic diagram which shows the discharge resistance apparatus with a cooler of 4th embodiment. It is an application pattern of the voltage to the 1st resistor in an experiment example.

  Hereinafter, a discharge resistor device with a cooler of the present invention will be described with reference to the drawings. Each embodiment described below is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified. In addition, in the drawings used in the following description, in order to make the features of the present invention easier to understand, there is a case where a main part is shown in an enlarged manner for convenience, and the dimensional ratio of each component is the same as the actual one. Not necessarily.

(First embodiment)
The discharge resistance device with a cooler of the first embodiment will be described with reference to FIG.
FIG. 1 is a cross-sectional view showing a discharge resistance device with a cooler according to a first embodiment of the present invention.
The discharge resistor device with a cooler 10 includes insulating layers 21 and 22 which are insulating substrates, a first resistor 23 formed on one surface side 21a of the insulating layer 21, and one surface of the insulating layer 22. The second resistor 24 formed on the side 22a, the metal layers 25 and 26 laminated on the other surface sides 21a and 22b of the insulating layers 21 and 22, respectively, and the common directly bonded to the metal layers 25 and 26 The cooler 31 is provided. In addition, electrodes 27 a and 27 b for energizing the first resistor 23 are provided on one surface side 21 a of the insulating layer 21, and the second resistor 24 is energized on one surface side 22 a of the insulating layer 22. Electrodes 28a and 28b are respectively formed.

The insulating layers 21 and 22 are made of, for example, ceramics such as Si ₃ N ₄ (silicon nitride), AlN (aluminum nitride), and Al ₂ O ₃ (alumina) that are excellent in insulation and heat dissipation. In the present embodiment, the insulating layers 21 and 22 are made of alumina. Moreover, the thickness of the insulating layers 21 and 22 is set within a range of 0.2 to 1.5 mm, for example, and is set to 0.635 mm in the present embodiment.

The first resistor (discharge resistor) 23 and the second resistor (discharge resistor) 24 function as electric resistances when voltages are applied to the electrodes 27a and 27b and the electrodes 28a and 28b, respectively. Is. Examples of the constituent material of the first resistor 23 and the second resistor 24 include a Ta—Si thin film resistor and a RuO ₂ thick film resistor. In the present embodiment, the first resistor 23 and the second resistor 24 are composed of a Ta—Si-based thin film resistor and have a thickness of, for example, 0.5 μm.

  The first resistor 23 and the second resistor 24 have different times (discharge speed) for discharging the applied voltage, and the first resistor 23 is applied more than the second resistor 24. The discharge resistor can discharge the generated voltage in a short time.

  For example, when the discharge resistor device with a cooler 10 of the present embodiment is used as an in-vehicle inverter device for an electric vehicle, the first resistor 23 is used when an abnormality such as a collision occurs in the electric vehicle. In order to ensure safety, the input terminals of the inverter device are discharged in a short time to ensure electrical safety (short-time discharge resistor). For this purpose, the first resistor 23 is connected to, for example, a switch element that is opened and closed by a signal from a collision sensor that detects a collision impact of the vehicle. The resistor 23 is energized.

  On the other hand, the second resistor 24 is used as a regular discharge resistor, such as discharging between the input terminals of the inverter device when the drive motor of the electric vehicle is stopped, and has a discharge rate higher than that of the first resistor 23. A low one is used.

  Due to the difference in characteristics of the discharge rate, the first resistor 23 generates a large amount of heat in a shorter time than the second resistor 24 during discharge. It is necessary to cool the body 24 more rapidly.

  The electrodes 27a and 27b and the electrodes 28a and 28b are electrical connection portions for applying voltages to the first resistor 23 and the second resistor 24, respectively, and are conductors such as Cu, Cu alloy, Alternatively, it is made of Al, Ag, silver-palladium alloy or the like. In this embodiment, it is made of Cu. The thickness is 1.5 μm, for example.

  The metal layers 25 and 26 are made of Al or an Al alloy. In the present embodiment, as the metal layers 25 and 26, plate-like members made of high-purity Al having a purity of 99.98 mass% or more are used. The thicknesses of the metal layers 25 and 26 may be 0.4 mm or more and 2.5 mm or less, for example. By forming the metal layers 25 and 26 between the insulating layers 21 and 22 and the cooler 31, respectively, the metal layers 25 and 26 function as a stress buffer layer. That is, the formation of the metal layers 25 and 26 absorbs the thermal stress generated by the difference in thermal expansion coefficient between the insulating layers 21 and 22 made of ceramics and the cooler 31 made of Al or Al alloy, and the insulating layers 21 and 22 are absorbed. Can be prevented from being damaged.

  Further, if the metal layers 25 and 26 are made of high-purity Al having a purity of 99.98 mass% or more, the deformation resistance is reduced, and the first resistor 23 and the second resistor 24 are heated and de-energized. The thermal stress generated in the insulating layers 21 and 22 can be effectively absorbed by the metal layers 25 and 26 when a cooling cycle due to repeated temperature drop is applied.

  The insulating layer 21 and the metal layer 25 and the insulating layer 22 and the metal layer 26 are directly joined using a brazing material. Examples of the brazing material include an Al—Cu based brazing material and an Al—Si based brazing material. In this embodiment, an Al—Si brazing material is used.

The cooler 31 has a heat dissipation area E2 and a heat absorption area E1 having a larger volume and a smaller surface area than the heat dissipation area E2. The heat radiation area E2 forms a position overlapping with the second resistor 24 serving as a regular discharge resistor along the stacking direction of the discharge resistor device 10 with the cooler. The cooler 31 includes a top plate portion 32 and a plurality of fins 33 formed on the top plate portion 32 in the heat radiation area E2. Here, the thermal conductivity of the cooler 31 is 90 W / mK or more, preferably 200 W / mK or more. Furthermore, the volume ratio of the top plate portion 32 in the heat radiation area E2 to the heat absorption area E1 is set to E1 / E2 = 3-10.
Moreover, the average heat transfer coefficient of the heat radiation area | region E2 is made into 8 times or more of the heat absorption area | region E1 by forming a fin. In the present invention, the average heat transfer coefficient of the heat radiating region E2 is an average heat transfer coefficient in terms of the top plate surface, that is, when it is assumed that the fin is not formed and is formed of a flat plate.

The fins 33, 33... Are plate-like members that are arranged at a predetermined interval from each other. The heat radiation area E2 of the cooler 31 has a surface area larger than that of the heat absorption area E1 by the fins 33, 33. A so-called air-cooled cooler that efficiently cools heat generated mainly by energization of the second resistor 24 by circulating air as a refrigerant through the gap (flow path) between the fins 33 and 33. Is configured.
Note that the heat dissipation region E2 of the cooler 31 may be a so-called water-cooled cooler in which, for example, a liquid flow path for circulating cooling water is integrally formed in contact with the top plate portion 32, for example.

  The top plate portion 32 and the fins 33, 33... Constituting the heat radiation area E2 of the cooler 31 are made of, for example, Al or Al alloy. Specifically, A3003, A1050, 4N-Al, A6063, etc. are mentioned. In this embodiment, a rolled plate of A1050 is used. In addition, even if the top plate portion 32 and the fins 33, 33... Are formed as an integral member, a plurality of fins 33, 33. Also good. When the top plate portion 32 and the plurality of fins 33, 33... Are configured as separate members, the top plate portion 32 and the plurality of fins 33, 33. Good.

  The endothermic region E1 of the cooler 31 is positioned so as to overlap the first resistor 23 serving as a short-time discharge resistor along the stacking direction of the discharge resistor device 10 with the cooler. Such an endothermic region E1 is made of a shape having a larger heat capacity than the heat radiating region E2, for example, solid lump Al or Al alloy.

  The heat absorption area E1 has a larger heat capacity than the heat dissipation area E2 and has a higher thermal conductivity. Therefore, due to these characteristics, the first resistor 23 has a shorter time than heat dissipation in the heat dissipation area E2. It is possible to absorb (heat transfer) a large amount of heat generated in a short time due to rapid energization. As a result, a rapid rise in temperature due to rapid energization of the first resistor 23 is prevented, and performance degradation and deterioration due to heat of the first resistor 23 are prevented.

  The endothermic region E1 of the cooler 31 is formed of, for example, an Al or Al alloy block body. Specifically, A3003, A1050, 4N-Al, A6063, etc. are mentioned. In this embodiment, the A1050 block body is used.

  In addition, the heat radiation area | region E2 and the heat absorption area | region E1 of such a cooler 31 should just be formed with the integral member. For example, by using a block-shaped Al alloy, fins 33, 33... Are formed by forming grooves that serve as air flow paths in portions overlapping the second resistor 24, and the heat dissipation region E2 is formed from one member. An endothermic region E1 can be formed. In this case, the boundary between the heat dissipation region E2 and the heat absorption region E1 is the center between the insulating layer 21 and the insulating layer 22 when the cooler 31 is viewed in plan.

  Alternatively, by using a plate-like Al alloy, the fins 33, 33... Are joined to the portion overlapping the second resistor 24, and the block-like Al alloy is joined to the portion overlapping the first resistor 23. Thus, the cooler 31 including the heat radiation area E2 and the heat absorption area E1 can be formed.

  The metal layers 25 and 26 and the cooler 31 are directly joined to each other. As a method of direct bonding between the metal layers 25 and 26 and the cooler 31, for example, direct bonding using an Al—Si brazing material can be applied. In the case of using an Al—Si brazing filler metal, for example, an Al—Si brazing filler metal foil is disposed between the metal layers 25 and 26 and the cooler 31 and heated at about 640 ° C. The Al—Si brazing material diffuses into the layers 25 and 26 and the cooler 31, and the metal layers 25 and 26 and the cooler 31 are directly joined.

As another method of direct joining of the metal layers 25 and 26 and the cooler 31, brazing using an Al—Si brazing material and a flux containing F (fluorine), for example, a flux mainly composed of KAlF ₄ is used. It can also be joined. In this case, bonding can be performed in an inert atmosphere such as nitrogen.

  Still another method of direct joining of the metal layers 25 and 26 and the cooler 31 is by fluxless brazing, in which brazing is performed using an Al—Si—Mg brazing material in an inert atmosphere such as nitrogen. It can also be joined.

  According to the discharge resistor device 10 with the cooler configured as described above, the cooler 31 has a heat dissipation region in accordance with the heat generation characteristics of the first resistor 23 and the second resistor 24 having different discharge times. By forming E2 and the endothermic region E1, the first resistor 23 and the second resistor 24 can be reliably cooled, and the discharge resistor device 10 with a cooler can be reduced in size and weight. to enable.

  That is, the first resistor 23 accompanied by the rapid heat dissipation by the short-time discharge is formed at a position overlapping the heat absorption region E1 of the cooler 31, so that the heat due to the rapid temperature rise of the first resistor 23 is increased. Heat can be absorbed quickly (heat transfer) in the heat absorption region E1 of the heat capacity, and the first resistor 23 can be cooled in a short time.

  The second resistor 24 with slow heat dissipation due to a relatively long discharge is formed at a position overlapping the heat dissipation region E2 of the cooler 31, so that the second resistor 24 is in contact with the refrigerant with a large surface area. It can cool reliably in area | region E2.

  For example, the endothermic region E1 overlapping the formation position of the first resistor 23 has a smaller surface area than the heat radiating region E2 and is formed in a block shape (lumb shape) having a large volume, so that a large surface area is required for the entire cooler. Compared to the case of forming a fin or the like, the discharge resistor device 10 with a cooler that is smaller and lighter can be realized.

  In the above-described embodiment, the independent insulating layers 21 and 22 and the metal layers 25 and 26 are formed corresponding to the first resistor 23 and the second resistor 24, respectively. In addition, one insulating layer or one metal layer common to the first resistor 23 and the second resistor 24 can be used.

  For example, when forming an in-vehicle inverter device using the discharge resistor device with a cooler 10 of the present invention, a power module constituting an inverter circuit is formed, and the second resistor 24 is used for motor operation. The first resistor 23 discharges between the input terminals of the inverter device in a short time to ensure safety when something abnormal, for example, a collision occurs, is discharged between the input terminals of the inverter device when stopped. The electrical safety may be ensured. The first resistor 23 directly discharges the capacitor when energized, and discharges the capacitor of the boost converter device through a diode built in the boost converter circuit.

(Second embodiment)
A discharge resistor device with a cooler according to a second embodiment will be described with reference to FIG.
FIG. 2 is a cross-sectional view showing a discharge resistance device with a cooler according to a second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member of the same structure as the discharge resistor apparatus with a cooler of 1st embodiment, and description of the detailed structure and effect | action is abbreviate | omitted.
The discharge resistor device with a cooler 40 of the second embodiment includes insulating layers 21 and 22 that are insulating substrates, a first resistor 23 formed on one surface side 21a of the insulating layer 21, and an insulating layer. A second resistor 24 formed on one surface side 22a of 22 and metal layers 25 and 26 made of Al or Al alloy, which are respectively laminated on the other surface sides 21a and 22b of the insulating layers 21 and 22. And a common cooler 51 directly bonded to the metal layers 25 and 26.

  In the present embodiment, heat conductors 52 and 53 containing Cu or Cu alloy are formed in a part of the cooler 51. Among these, the heat conductor 52 is made of block-like Cu or Cu alloy, and is formed in the heat absorption region E1 overlapping the first resistor 23 which is a short-time discharge resistor. The heat conductor 52 is formed so as to be embedded in the heat absorbing region E1 of the cooler 51 with the upper surface exposed. The thickness of the heat conductor 52 is preferably 5 mm to 30 mm. In this embodiment, the heat conductor 52 is formed of oxygen-free copper having a thickness of 10 mm. And the heat conductor 52 and the metal layer 25, and the heat conductor 52 and the cooler 51 are joined by solid phase diffusion bonding, respectively.

  The heat conductor 53 is made of a thin plate-like Cu or Cu alloy, and is formed in the heat dissipation region E2 that overlaps the second resistor 24 that is a regular discharge resistor. The thickness of the heat conductor 53 is preferably 0.1 mm to 3 mm. In the present embodiment, the heat conductor 53 is formed of oxygen-free copper having a thickness of 2 mm. The heat conductor 53 and the metal layer 26, and the heat conductor 53 and the cooler 51 are joined by solid phase diffusion bonding.

  When these heat conductor 52 and metal layer 25, heat conductor 52 and cooler 51, heat conductor 53 and metal layer 26, and heat conductor 53 and cooler 51 are directly bonded by solid phase diffusion bonding, For example, the metal layers 25 and 26 made of Al or Al alloy, the cooler 41, and the heat conductors 52 and 53 made of Cu or Cu alloy are surface-treated, and pressure is applied while heating at about 500 to 600 ° C. Thus, solid phase diffusion can be performed at the bonding surfaces of these members, and bonding can be performed by solid phase diffusion bonding using different metals of Al or Al alloy and Cu or Cu alloy.

  According to the discharge resistor device with a cooler 40 of the second embodiment, the heat absorption region E1 overlapping the first resistor 23, which is a short-time discharge resistor, has a block shape made of Cu, which has better thermal conductivity than Al. By forming the heat conductor 52, the heat due to the rapid temperature rise generated in the first resistor 23 can be absorbed more quickly, and the cooling efficiency of the first resistor 23, which is a short-time discharge resistor, is improved. Can be further enhanced.

  Also, by forming a plate-like thermal conductor 53 made of Cu or Cu alloy having better thermal conductivity than Al also in the heat dissipation region E2 overlapping the second resistor 24 which is a common discharge resistor, The heat generated in the second resistor 24 can be efficiently propagated to the heat radiation area E2 of the cooler 51, and the cooling efficiency of the second resistor 24 can be further increased.

(Third embodiment)
A discharge resistor device with a cooler according to a third embodiment will be described with reference to FIG.
FIG. 3 is a cross-sectional view showing a discharge resistor device with a cooler according to a third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member of the same structure as the discharge resistor apparatus with a cooler of 1st embodiment, and description of the detailed structure and effect | action is abbreviate | omitted.
The discharge resistor device 60 with a cooler according to the third embodiment includes insulating layers 21 and 22 that are insulating substrates, a first resistor 23 formed on one surface side 21a of the insulating layer 21, and an insulating layer. A second resistor 24 formed on one surface side 22a of 22 and metal layers 25 and 26 made of Al or Al alloy, which are respectively laminated on the other surface sides 21a and 22b of the insulating layers 21 and 22. And a common cooler 71 joined directly to the metal layers 25 and 26.

  In the present embodiment, the cooler 71 is made of, for example, A1050, and a heat conductor 72 containing Cu or a Cu alloy is embedded in the heat absorption region E1. The heat conductor 72 is made of, for example, block-like Cu or Cu alloy. In order to embed and form such a heat conductor 72 in the cooler 71, the cooler 71 includes an upper member 71A and a lower member 71B that can be divided from each other. The upper member 71A is a flat plate-like member, and a recess 73 capable of accommodating the heat conductor 72 is formed in the heat absorption region E1 of the lower member 71B.

  In the cooler 71 of the present embodiment, after the thermal conductor 72 is accommodated in the recess 73 of the lower member 71B and solid phase diffusion bonded, the upper member 71A and the lower member 71B are covered so as to cover the thermal conductor 72. For example, the screws 75 are fastened and integrated. In addition, it is preferable to apply heat conductive thermal grease to the contact surface between the upper member 71A and the lower member 71B to enhance the adhesion.

  According to the discharge resistor device 60 with the cooler of the third embodiment, the heat absorption region E1 overlapping the first resistor 23, which is a short-time discharge resistor, has a block shape made of Cu that has better thermal conductivity than Al. By embedding the heat conductor 72, the heat due to the rapid temperature rise generated in the first resistor 23 can be absorbed more quickly, and the first resistor 23 which is a short-time discharge resistor. It becomes possible to further increase the cooling efficiency of the.

(Fourth embodiment)
A discharge resistance device with a cooler according to a fourth embodiment will be described with reference to FIG.
FIG. 4 is a schematic view when the discharge resistance device with a cooler of the fourth embodiment of the present invention is viewed from the cooler side. In addition, the same code | symbol is attached | subjected to the member of the same structure as the discharge resistor apparatus with a cooler of 1st embodiment, and description of the detailed structure and effect | action is abbreviate | omitted.
In the discharge resistor device 80 with the cooler of the fourth embodiment, the second resistor 24, which is a regular discharge resistor, is formed at a position overlapping the heat dissipation area E2 of the cooler 91, and at a position overlapping the heat absorption area E1. A first resistor 23 which is a short-time discharge resistor is formed. Further, the heat radiation area E2 further extends outside the area where the first resistor 23 is formed, and insulated gate bipolar transistors (IGBT) 93, 93. Region E3).

  And the flow path 92 which distribute | circulates cooling water as a refrigerant | coolant is formed in the thermal radiation area | region E2 and the 2nd thermal radiation area | region E3. On the other hand, the endothermic region E1 is made of a block-like Al alloy that increases the heat capacity, and the flow path 92 is not formed.

  According to the discharge resistor device 80 with the cooler of the fourth embodiment, the heat dissipation region E2 that overlaps the second resistor 24, which is a regular discharge resistor, and the second heat dissipation region E3 that overlaps the IGBTs 93, 93. A cooling water flow path 92 is formed on the first resistor 23, and a heat absorption region E1 overlapping the first resistor 23, which is a short-time discharge resistor, is formed in a block shape to increase the heat capacity. By forming the cooler 91 in an optimal shape according to the heat generation characteristics of the second resistor 24 and the IGBT 93, the discharge resistor device 80 with a cooler can be reduced in size and weight.

  As mentioned above, although some embodiment of this invention was described, these each embodiment was shown as an example and is not intending limiting the range of invention. Each of these embodiments can be implemented in various other forms, and various omissions, replacements, additions, or changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof, as long as they are included in the scope and gist of the invention.

Hereinafter, experimental examples in which the effects of the present embodiment are verified will be shown.
(Equivalent to the discharge resistance device with a cooler of the structure shown in Example 1 and the first embodiment)
After forming the first and second resistors (Ta-Si thin film resistors, 10 mm × 5 mm) on an alumina substrate having a thickness of 0.635 mm, an electrode made of Cu was formed. The alumina substrates on which the first and second resistors are formed are made of an Al—Si brazing material, a 4N—Al metal layer (10 mm × 5 mm, thickness 2 mm), an Al—Si brazing material, and an A1050 material, respectively. The layers were stacked in the order of a cooler (50 mm × 20 mm, thickness 15 mm), and each was bonded by heating at 610 ° C. in a vacuum. The first resistor was formed in the heat absorption region E1, and the second resistor was formed in the heat dissipation region E2. In the heat radiation area E2, the fin height of the cooler was 12 mm, the fin thickness was 1 mm, and the fin interval was 1.5 mm. In Example 1, the volume is 7500 mm ³ endothermic region E1, the volume of the top plate portion and a fin portion of the heat radiation region E2 is 3900 mm ^3, the average heat transfer coefficient of the heat absorption area E1 is ^{10W / (m 2 · K)} , the heat radiation region the average heat transfer coefficient of the top plate in terms of E2 is ^{100W / (m 2 · K)} , the surface area of the endothermic area E1 is 1850 mm ^2, the surface area of the heat radiation region E2 is 5750mm ^2. The volume occupied by the cooler in Example 1 (the volume of the heat absorption area E1 + the volume of the top and fins of the heat dissipation area E2 and the volume of the space formed by the fins of the heat dissipation area E2) was 15000 mm ³ . .

(Example 2, equivalent to a discharge resistor device with a cooler having the structure shown in the second embodiment)
After forming the first and second resistors (Ta-Si thin film resistors, 10 mm × 5 mm) on an alumina substrate having a thickness of 0.635 mm, an electrode made of Cu was formed. On the other side of the alumina substrate on which the first and second resistors are formed, a 4N-Al material (10 mm × 5 mm, thickness 2 mm) is laminated through an Al—Si brazing material at 640 ° C. Joined by heating in vacuum. Then, a cooler made of A1050 is engraved and processed, and the processed part is used as an endothermic region E1, oxygen-free copper having a thickness of 20 mm × 15 mm and a thickness of 10 mm is disposed, and in the heat dissipation region E2, 20 mm × 15 mm and a thickness of 2 mm. Oxygen-free copper was placed on the alumina substrate on which the first and second resistors were formed by joining the metal layer on the other side, and at each position in a vacuum at 530 ° C. It heated and joined by solid phase diffusion bonding.
In the heat radiation area E2, the fin height of the cooler was 12 mm, the fin thickness was 1 mm, and the fin interval was 1.5 mm. In Example 2, the volume is 7500 mm ³ endothermic region E1, the volume of the top plate portion and a fin portion of the heat radiation region E2 is 3900 mm ^3, the average heat transfer coefficient of the heat absorption area E1 is ^{10W / (m 2 · K)} , the heat radiation region the average heat transfer coefficient of the top plate in terms of E2 is ^{100W / (m 2 · K)} , the surface area of the endothermic area E1 is 1850 mm ^2, the surface area of the heat radiation region E2 is 5750mm ^2. In addition, the occupied volume of the cooler in Example 2 (the volume of the endothermic region E1 + the volume of the top plate portion and the fin portion of the heat radiating region E2 + the volume of the space formed by the fins of the heat radiating region E2) was 15000 mm ³ . .

(Comparative Example 1)
In Example 1, it was manufactured using a cooler having a top plate thickness of 10 mm and a fin height of 12 mm. In Comparative Example 1, fins are also formed in the endothermic region E1.
In Comparative Example 1, the volume of the endothermic region E1 including the fins is 7400 mm ³ , the volume of the top plate portion and the fin portion of the heat dissipation region E2 is also 7400 mm ³ , and the average heat transfer coefficient in terms of the top plate portion of the endothermic region E1 is 100 W / ( m ² · K), the average heat transfer coefficient of the heat dissipation region E2 is 100 W / (m ² · K), the surface area of the heat absorption region E1 is 6240 mm ² , and the surface area of the heat dissipation region E2 is 6240 mm ² . Note that the volume occupied by the cooler in Comparative Example 1 (the volume including the fins of the endothermic region E1 + the volume of the top plate and fins of the heat dissipation region E2 + the volume of the space formed by the fins of the endothermic region E1 and the heat dissipation region E2) ) Was 22000 mm ³ .

(Comparative Example 2)
The same procedure as in Example 1 was performed except that the top plate thickness was 3 mm, the fin height was 12 mm, and the cooler shape was 75 mm × 20 mm. In Comparative Example 2, fins are also formed in the endothermic region E1.
In Comparative Example 2, the volume of the endothermic region E1 including the fin is 5850 mm ³ , the volume of the top plate portion and the fin portion of the heat dissipation region E2 is also 5850 mm ³ , and the average heat transfer coefficient of the top plate portion of the endothermic region E1 is 100 W / (m ² · K), the average heat transfer coefficient in terms of the top plate of the heat radiation area E2 is 100 W / (m ² · K), the surface area of the heat absorption area E1 is 8595 mm ² , and the surface area of the heat radiation area E2 is 8595 mm ² . In addition, the occupied volume of the cooler in Comparative Example 2 (the volume including the fins of the heat absorption region E1 + the volume of the top and the fins of the heat dissipation region E2 + the volume of the space formed by the fins of the heat dissipation region E2) is 22500 mm ^3. Met.

(Comparative Example 3)
Manufactured in the same manner as in Example 1 except that the second resistor was formed in the heat absorbing region E1 and the first resistor was formed in the heat radiating region E2.

(Evaluation)
The maximum temperature of the first resistor was measured with a thermocouple when a voltage was applied to the first resistor so that the obtained discharge resistance device with a cooler had the discharge pattern shown in FIG. Moreover, the temperature at the time of making the 2nd resistor produce steady heat at 5W was measured with the thermocouple. Table 1 shows the ratio when the occupied volume of Example 1 is 1.

  In the examples, the first resistor temperature and the second resistor temperature satisfy 95 ° C. or less, but Comparative Example 1 and Comparative Example 2 have an occupied volume ratio of 1.5 times the entire cooler. Nevertheless, it can be seen that the temperature of the first resistor does not satisfy 95 ° C. or lower. Further, in Comparative Example 3 in which the first resistor is disposed in the heat dissipation region E2 and the second resistor is disposed in the heat absorption region E1, the temperature of the first resistor and the second resistor is 95 ° C. or less. Not satisfied.

DESCRIPTION OF SYMBOLS 10 Discharge resistance apparatus 21 and 22 with a cooler Insulating layer 23 1st resistor 24 2nd resistor 25 and 26 Metal layer 31 Cooler E2 Heat dissipation area E1 Endothermic area

Claims (6)

An insulating layer made of ceramic, a first resistor and a second resistor formed side by side on one surface side of the insulating layer, a metal layer and a cooling layer sequentially laminated on the other surface side of the insulating layer A discharge resistance device with a cooler comprising:
The metal layer and the cooler are made of Al or Al alloy,
The cooler has a heat dissipation region, and a heat absorption region having a volume larger than that of the heat dissipation region and a small surface area,
The first resistor is a discharge resistor capable of discharging the applied voltage in a short time than the second resistor,
The discharge resistor device with a cooler, wherein the first resistor is formed at a position overlapping with the heat absorption region, and the second resistor is formed at a position overlapping with the heat dissipation region.   The discharge resistance device with a cooler according to claim 1, wherein the insulating layer and the metal layer, and the metal layer and the cooler are directly joined to each other.   A heat conductor containing Cu or a Cu alloy is further formed in a part of the cooler, and the cooler and the heat conductor, and the metal layer and the heat conductor are joined by solid diffusion bonding, respectively. The discharge resistance device with a cooler according to claim 1, wherein the discharge resistance device has a cooler.   The discharge resistance device with a cooler according to any one of claims 1 to 3, wherein a flow path through which a refrigerant flows is formed in the heat radiation region.   5. The discharge resistance device with a cooler according to claim 1, wherein the insulating layer and the metal layer are bonded using an Al—Si brazing material. 6.   The discharge resistance device with a cooler according to any one of claims 1 to 5, wherein the metal layer has a thickness of 0.6 mm or more and 2.5 mm or less.

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