JP2002009216A - Circuit device with cooling fluid refrigeration - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce drive power for cooling fluid in a circuit device with cooling fluid refrigeration using a flat molded tube. SOLUTION: In a large heat generating circuit component 1, there is closely arranged a first tube section 4 of a once-through tube for cooling fluid, composed of a metal extrusion molding or a metal draw molding which has a mutually parallel pair of flat surfaces for refrigeration. A second tube section 5 of the once-through tube for cooling fluid is closely arranged in a small heat generating circuit component. The tube section 4 is connected with the tube section 5 through a third tube section, thus, the cooling fluid flows from the tube section 4 to the tube section 5 through the third tube section 6. The tube section 4 has a member cross-sectional area and a contact surface area of the cooling fluid larger than those of the tube section 5, and a passage cross-sectional area of the cooling fluid smaller than that of the tube section 5, thereby acquiring necessary cooling capability and reducing pressure loss.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling fluid cooling type circuit device.

[0002]

2. Description of the Related Art In recent years, a semiconductor module used for an inverter device for driving a traction motor in an electric vehicle generates a large amount of heat due to the necessity of high-power switching. It has the following characteristics. In order to cool the semiconductor module, a radiator system for cooling the engine of the electric vehicle and a vehicle air conditioner can be used in common. Conventionally adopted, a system using an air-conditioning refrigerant is also considered. Hereinafter, a circuit device employing this type of cooling system will be referred to as a cooling fluid cooling type circuit device.

[0003]

In this cooling fluid cooling type circuit device, it is conceivable to employ a structure in which a cooling fluid flow-through tube is closely attached to a circuit component which generates heat directly or via a good heat conducting member. In this case, the cooling fluid flow-through tube and the contact heat transfer surface of the circuit component which are in close contact with each other are preferably formed flat. However, the cooling fluid flow-through tube having a flat contact heat transfer surface (cooling flat surface) is preferable. It is conceivable to use a flat tube made of a metal extruded product or a metal drawn product. This type of flat type tube is mass-produced for an indirect heat exchanger (a condenser or an evaporator) of an air conditioner, and is extremely inexpensive.

[0004] Next, the case where this flat tube is closely attached to each circuit component constituting the circuit device will be considered. It is simplest in structure to arrange the flat Heisei tube so as to loop around each circuit component in order. However, in this case, since the heat value and the size of each circuit component are different from each other, if the cooling capacity of the flat type tube is designed in accordance with the cooling of the circuit component that is small, has a small contact heat transfer surface, and generates a large amount of heat, a large In a circuit component having a large contact heat transfer surface or a circuit component generating a small amount of heat, the amount of heat generated per unit area of the contact heat transfer surface (ie, heat generation density) is small, so that the cooling capacity becomes excessive.
Since the flat tube has a pressure loss, it is necessary to increase the size of the pump and increase the pump power in proportion to the length of the tube.

After all, in a cooling fluid cooling type circuit device in which a flat type tube is routed around a plurality of circuit components sequentially, the driving power of the cooling fluid increases as the number of circuit components increases. And increase of energy consumption has been a problem.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and has as its object to reduce the driving power of a cooling fluid in a cooling fluid cooling type circuit device using a flat tube.

[0007]

According to a first aspect of the present invention, there is provided a cooling fluid cooling type circuit device comprising a metal extruded part or a metal drawn part having a pair of parallel flat cooling surfaces. And a cooling fluid cooling type circuit device including a large heat generating circuit component and a small heat generating circuit component that are closely attached to the cooling flat surface of the cooling fluid through tube directly or through a heat transfer member, wherein the cooling fluid through tube is A first tube portion that is in close contact with the large heat generating circuit component, and a second tube portion that is connected in series with the first tube portion and is in close contact with the small heat generating circuit component, wherein the first tube portion is It has a member cross-sectional area and a cooling fluid contact surface area larger than the second pipe portion, and a cooling fluid flow path cross-sectional area smaller than the second pipe portion.

That is, according to the present invention, a cooling fluid flow-through tube, which is a metal extrusion molded product or a metal drawn molded product having a pair of cooling flat surfaces parallel to each other, that is, a flat Heisei tube is formed by connecting a plurality of circuit parts. The cooling of circuit components is ensured by changing the cross-sectional shape of the flat heating tube in contact with the large heating circuit components and the flat heating tube portion in contact with the small heating circuit components when routing around While reducing the overall pressure loss.

More specifically, since the flat tube has a large member cross-sectional area and a cooling fluid contact surface area in contact with a large heat generating circuit component, it can have a small heat transfer resistance and a large heat sink performance. This is because, in this type of cooling fluid indirect cooling type heat transfer system, the heat transfer resistance at the boundary between the flat tube and the cooling fluid (also referred to as a boundary layer) becomes dominant, which causes the fluid to flow. This is because the boundary layer of the cooling fluid has a substantially low moving speed and a small flow turbulence. In order to cope with this, the first tube part in contact with the large heat generating circuit component has a large cross-sectional area of the flat type tube to improve the heat sink mass performance, and further increases the cooling fluid contact surface area to improve the heat radiation ability. are doing. However, the increase in the above-mentioned member cross-sectional area and the cooling fluid contact surface area in the flat Heisei type tube causes an increase in pressure loss of the cooling fluid.

On the other hand, since the flat type tube has a small member cross-sectional area and a cooling fluid contact surface area in contact with a small heat generating circuit component, it has a large heat transfer resistance and a small heat sink performance. However, since the heat generation of the small heat generating circuit component is small, the temperature rise of the small heat generating circuit component can be sufficiently maintained within its allowable temperature range. Further, since the flat type tube has a large cooling fluid flow path cross-sectional area in contact with the small heat generating circuit component, it is possible to reduce a pressure loss in this portion.
As a result, according to the present configuration, it is possible to reduce the overall pressure loss and to reduce the size of the cooling fluid drive device and reduce the drive energy while ensuring good cooling of both heat-generating components.

Further, since the cooling fluid flow-through tube, that is, the cooling system can be constituted by a cooling fluid path of one circuit in total, connection and the like can be simplified.

According to a second aspect of the present invention, in the cooling fluid-cooled circuit device according to the first aspect, the first pipe portion is further arranged upstream of the second pipe portion. I have. According to this configuration, since the large heat generating circuit components can be cooled with a cooler cooling fluid, the cooling performance of the large heat generating circuit components can be improved without complicating the cooling device configuration.

According to a third aspect of the present invention, in the cooling fluid-cooled circuit device according to the first aspect, a third pipe connecting an end of the first pipe and an end of the second pipe. The third pipe section has a single flow path and is fitted and joined to the first pipe section and the second pipe section, respectively. According to this configuration, since the pipe is a single pipe (a pipe having a single flow path) and is fitted to and joined to the ends of the first pipe section and the second pipe section, the pressure loss is minimized. And it is easy to deform for routing, and a piping structure having a complicated shape can be easily manufactured.

According to a fourth aspect of the present invention, in the cooling fluid-cooled circuit device according to the third aspect, the third tube portion is curved in a U shape, and the first and second tube portions are curved. Third
It is characterized by being in close contact with both sides of the circuit component. According to this configuration, the first tube portion and the second tube portion are formed on the third circuit component or both surfaces of the first circuit component by bending the third tube portion that is easily deformed and has a small pressure loss into a U shape. Due to the close contact, three or more circuit components can be cooled with a simple and compact cooling piping structure.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a cooling fluid cooling type circuit device according to the present invention will be described below with reference to the drawings.

[0016]

Embodiment 1 FIG. 1 is a side view of this cooling fluid cooling type circuit device, and FIG. 2 is a cross-sectional view taken along the line BB of FIG.

Reference numeral 1 denotes a first heating element which generates the largest amount of heat, and is constituted by a semiconductor module forming a three-phase inverter circuit for controlling driving of a traveling motor of an electric vehicle.
Reference numerals 2a and 2b denote second heating elements, each of which is constituted by a smoothing capacitor connected between a pair of DC input terminals of the three-phase inverter circuit. 3 is a third heating element, 20
It comprises a step-down DC-DC converter interposed between a main battery of 0 V or more and an auxiliary battery of 12 V for charging the auxiliary battery.

Reference numeral 4 denotes a flat tube (first tube) which is manufactured by extruding or drawing an aluminum material, and has a slit-shaped flow passage (partly defined by a partition wall) through which a cooling fluid flows in parallel. A large number of flow paths 4a are formed in parallel.

Reference numeral 5 denotes a flat tube (second tube portion) manufactured by extruding or drawing an aluminum material. Inside the slit tube, a slit-shaped flow portion (partially divided by a partition wall) through which a cooling fluid flows in parallel. Many channels 5a are formed in parallel. As shown in FIG.
Although the shape of each partition in the inside is the same,
Are formed twice as many as the flat tube 5, and the total cross-sectional area of the flow path 4a of the flat tube 4 is smaller than that of the flat tube 5.

Reference numeral 6 denotes a flat tube (third tube) manufactured by extruding or drawing an aluminum material.
It has a single channel without a partition inside. The flat tube 6 is formed into a U-shape and is crimped to the same end of the cooling fluid flow-through tubes 4 and 6 arranged in parallel with each other and joined by brazing.

Reference numerals 7 and 8 denote headers joined to the other ends of the cooling fluid flow-through tubes 4 and 5, which are joined by brazing. At one end of each of the headers 7 and 8, a male screw pipe portion for connecting a pipe is provided. Each of the semiconductor module 1, the smoothing capacitors 2a and 2b, and the DC-DC converter 3 has a flat heat dissipation
~ 6 flat heat transfer surfaces. The number of smoothing capacitors is not limited to two, but may be configured as one integrated or three. The semiconductor module 1 is also a 6-in-1 type in which six arms of a three-phase inverter are one module, and a two-in-one type in which one-phase two arms are one module.
Even with three types, one arm is one module
Six in1 types may be used. Smoothing capacitors 2a, 2b
Is an oval type capacitor and both sides are flat,
It can be easily cooled from both sides.

The heat value of the semiconductor module 1 is DC-DC
It is several times to several tens times larger than that of converter 3.
The amount of heat generated by the smoothing capacitors 2a and 2b is smaller than that of the DC / DC converter 3.

According to this structure, the flat tube 1 for cooling the semiconductor module 1 which is a large heat generating circuit component can have a small heat transfer resistance and a large heat sink mass characteristic, and the DC / DC small heat generating circuit component can be obtained. Converter 3
Has a large flow path cross-sectional area and low pressure loss (small fluid resistance), so it is possible to reduce the pressure loss while securing the necessary cooling performance as a whole, and to realize a downsized pump and reduced pump driving power. be able to.

Further, in this embodiment, the easily deformable flat tube 6 having no partition therein is used for connecting the flat tubes 4 and 5, so that the third tube portion not involved in the cooling of the circuit parts is used. The third tube portion is curved in a U-shape, and the circuit components 1 to 3 and the flat tubes 4 and 5 can be stacked and arranged, which complicates the routing of the cooling pipe. The device can be made compact without the need for it.

Further, if the width between both ends of the U-shaped curved third tube portion is slightly smaller than the lamination thickness of the laminated assembly, the third tube portion clamps the laminated assembly, so that the heat is generated. Good coupling is achieved and cooling can be performed efficiently. Further, the smoothing capacitors 2a and 2b can also function as a heat sink mass of the semiconductor module 1.

Further, in this embodiment, the cooling fluid flows from the first pipe section 4 to the second pipe section 5 via the third pipe section 6, and the semiconductor module which is a large heat generating circuit component is still heated on the upstream side. Since the semiconductor module 1 is cooled by the cooling fluid that has not been cooled, the cooling performance of the semiconductor module 1 that requires strong cooling can be improved.

[0027]

Embodiment 2 Another embodiment of the apparatus of the present invention will be described with reference to FIG.

The device shown in FIG. 3 is different from the device shown in FIG. 1 in that the positions of the semiconductor module 1 and the smoothing capacitors 2a and 2b are reversed. However, a double-sided cooling type semiconductor module is adopted as the semiconductor module 1.

In this way, since the semiconductor module 1 can be cooled from both sides, the cooling performance can be further improved. Further, since the semiconductor module 1 can transiently dissipate heat to the smoothing capacitors 2a and 2b through the flat tube (first tube portion) 4 having a small heat transfer resistance and containing many partition walls, the smoothing capacitor 2
a and 2b can exhibit the heat sink mass function of the semiconductor module 1.

(Modification) In the above embodiment, the third tube portion 6 which is a flat Heisei type tube is an aluminum extruded molded product or an aluminum drawn molded product. If so, other structures, shapes,
It may be manufactured using a material.

[Brief description of the drawings]

FIG. 1 is a side view of a cooling fluid cooling type circuit device according to a first embodiment.

FIG. 2 is a sectional view of the cooling fluid cooling type circuit device shown in FIG.

FIG. 3 is a side view of a cooling fluid cooling type circuit device according to a second embodiment.

[Explanation of symbols]

 1: Semiconductor module (large heat generating circuit parts) 3: DC-DC converter (small heat generating circuit parts) 4: Flat Heisei type tube (first pipe part) 5: Flat Heisei type tube (second pipe part) 6: Flat Heisei type tube ( 3rd pipe)

Claims (4)

[Claims] A cooling fluid flow-through tube comprising a metal extrusion or a metal pultrusion having a pair of cooling flat surfaces parallel to each other, and directly or directly on said cooling flat surface of said cooling fluid flow-through tube. In a cooling fluid cooling type circuit device including a large heat generating circuit component and a small heat generating circuit component which are arranged in close contact with each other through a heat transfer member, the cooling fluid flow-through tube includes: a first pipe portion which is in close contact with the large heat generating circuit component; A second tube portion connected in series with the one tube portion and in close contact with the small heat generating circuit component, wherein the first tube portion has a larger member cross-sectional area and a cooling fluid contact surface area than the second tube portion; A cooling fluid-cooled circuit device having a cooling fluid passage cross-sectional area smaller than that of the second pipe portion. 2. The cooling fluid-cooled circuit device according to claim 1, wherein said first pipe portion is disposed upstream of said second pipe portion. 3. The cooling fluid-cooled circuit device according to claim 1, further comprising: a third pipe connecting an end of said first pipe to an end of said second pipe. A cooling fluid cooling type circuit device, wherein the pipe section has a single flow path and is fitted and joined to each of the first pipe section and the second pipe section. 4. The cooling fluid-cooled circuit device according to claim 3, wherein said third pipe is curved in a U-shape, and said first and second pipes are third circuit components or said third pipe. A cooling-fluid-cooled circuit device, wherein the circuit component is disposed in close contact with both surfaces of the circuit component directly or through a heat transfer member.