Water cooling device for power conversion device, flow rate adjustment mechanism for water cooling device, and flow rate adjustment method for water cooling device

Abstract

A water cooling device for a power conversion device according to an embodiment comprises a flow rate adjustment mechanism that is detachably inserted into a base for pipe connection in a water cooling path of the power conversion device, the flow rate adjustment mechanism narrowing the flow path diameter in the base. A flow rate adjustment mechanism of a water cooling device according to an embodiment is detachably inserted into a base for pipe connection in a water cooling path of an apparatus, the flow rate adjustment mechanism narrowing the flow path diameter in the base. In a flow rate adjustment method for a water cooling device according to an embodiment, a plurality of the aforementioned flow rate adjustment mechanisms are set with different inside diameters, and a flow rate adjustment mechanism is selected from the plurality of flow rate adjustment mechanisms and is attached to the base.

Description

Water cooling device for power converter, flow rate adjustment mechanism for water cooling device, and flow rate adjustment method for water cooling device

[0001] Embodiments of the present invention relate to a water cooling device for a power converter, a flow rate adjustment mechanism for the water cooling device, and a flow rate adjustment method for the water cooling device.

[0002] Conventionally, in water-cooled power converters, devices with different pressure losses may be connected to allow cooling water to flow therethrough. In this case, a valve-type adjustment mechanism for pressure loss harmonization may be provided, or a functional unit that increases the pressure loss may be provided.

[0003] However, in the configuration provided with the valve-type adjustment mechanism, a flow meter is required in addition to the valve, and flow rate adjustment work by a qualified person is necessary. In addition, as the piping shape becomes more complex, the housing size increases. Moreover, the configuration in which another functional unit is provided leads to an increase in size and complexity of the water cooling path.

[0004] Japanese Unexamined Patent Application Publication No. 2011-198802

[0005] The problem to be solved by the present invention is to provide a water cooling device for a power converter, a flow rate adjustment mechanism for the water cooling device, and a flow rate adjustment method for the water cooling device, which facilitate flow rate adjustment and can achieve space saving and simplification.

[0006] A water cooling device for a power converter according to an embodiment includes a flow rate adjustment mechanism that is detachably inserted into a pipe connection mouthpiece in a water cooling path of the power converter and restricts the flow path diameter in the mouthpiece. A flow rate adjustment mechanism for a water cooling device according to an embodiment is detachably inserted into a pipe connection mouthpiece in a water cooling path of equipment, and restricts the flow path diameter in the mouthpiece. A flow rate adjustment method for a water cooling device according to an embodiment includes a flow rate adjustment mechanism that is detachably inserted into a pipe connection mouthpiece in a water cooling path of equipment and restricts the flow path diameter in the mouthpiece, wherein a plurality of the flow rate adjustment mechanisms with different inner diameters are set, and one of the plurality of flow rate adjustment mechanisms is selected and attached to the mouthpiece.

[0007] A configuration diagram of a power converter according to an embodiment. A perspective view of a flow rate adjustment mechanism according to an embodiment. A plan view of the flow rate adjustment mechanism according to the embodiment viewed from the axial direction. A half cross-sectional view taken along line IV-IV in FIG. 3. An enlarged view of a mouthpiece portion of a water cooling system of a power converter. An enlarged view of a state where a hose is attached to the mouthpiece of FIG. 5.

[0008] The water cooling system, flow rate adjustment mechanism, and flow rate adjustment method of the power converter according to the embodiment will be described below with reference to the drawings.

[0009] Figure 1 is a configuration diagram of a power converter 1 of an embodiment, including a water cooling system 2. The power converter 1 converts an AC voltage from a power grid into a DC voltage using a converter (neither of which are shown), and then converts this DC voltage back into an AC voltage using a plurality of inverters 3. Each inverter 3 comprises a U-phase unit inverter 3u, a V-phase unit inverter 3v, and a W-phase unit inverter 3w. Each phase unit inverter is equipped with a semiconductor switching element (not shown), such as an IGBT. In each unit inverter, the semiconductor switching element is mounted on a water-cooled heat sink 5.

[0010] The heat sink 5 is equipped with a water supply pipe for introducing cooling water into its internal flow path and a drain pipe for discharging cooling water from its internal flow path (neither of which are shown). For example, the water supply pipes for the three phases of the heat sink 5 are connected to the water supply manifold pipe 9a via a water supply hose 7a. The drain pipes for the three phases of the heat sink 5 are connected to the drain manifold pipe 9b via a drain hose 7b. Hereinafter, the water supply hose 7a and the drain hose 7b will be collectively referred to as hose 7, and the water supply manifold pipe 9a and the drain manifold pipe 9b will be collectively referred to as manifold pipe 9.

[0011] The manifold piping 9 is included in the external flow path 10 outside the heat sink 5. The external flow path 10 is connected to the refrigerant circulation device and heat exchanger (neither of which are shown) outside the power converter 1.

[0012] Figure 5 is an explanatory diagram of the nozzle 20 portion of the water cooling system 2 of the power converter 1. Figure 6 is an enlarged view of the nozzle 20 in Figure 5 with a hose 7 attached. As shown in Figures 5 and 6, the manifold piping 9 is provided with multiple nozzles 20 for connecting multiple hoses 7. A hose 7, for example made of rubber, is fitted onto each nozzle 20 and connected. The manifold piping 9 and the heat sink 5 are connected via these hoses 7.

[0013] Each nozzle 20 is fitted with a flow rate adjustment mechanism 20 that allows the flow rate to be adjusted by generating a predetermined pressure loss.

[0014] Figure 2 is a perspective view of the flow rate adjustment mechanism 20. Figure 3 is a plan view of the flow rate adjustment mechanism 20 as seen from its axial direction. Figure 4 is a semi-cross-sectional view along the line IV-IV in Figure 3. Referring to Figures 2 to 4, the flow rate adjustment mechanism 20 of the embodiment is a cylindrical member and can be coaxially inserted into a cylindrical nozzle 20. Line C1 in the figures indicates the central axis of the flow rate adjustment mechanism 20.

[0015] The flow rate adjustment mechanism 20 is integrally formed from metal or resin. The flow rate adjustment mechanism 20 includes a small-diameter portion 21 that is inserted into the nozzle 20 through an opening at the tip of the nozzle 20, and a large-diameter portion 25 that is formed by expanding the diameter at one axial end of the small-diameter portion 21 and contacts the tip of the nozzle 20.

[0016] The small-diameter portion 21 has an outer diameter A that matches the inner diameter of the nozzle 20 into which it is inserted. The outer diameter A has a small overlap relative to the inner diameter of the nozzle 20, so that the flow rate adjustment mechanism 20 does not easily fall out of the nozzle 20, and so that the flow rate adjustment mechanism 20 can be attached and detached by hand or with a hand tool.

[0017] The large-diameter section 25 has an outer diameter B that is equivalent to the outer diameter A of the tip of the nozzle 20. Multiple tapered shapes 15 are formed on the outer circumference of the nozzle 20, arranged in the axial direction. Each tapered shape 15 is formed to widen towards the base 14 of the nozzle 20. These multiple tapered shapes 15 serve to prevent the hose 7 attached to the nozzle 20 from coming off. The large-diameter section 25 has an outer diameter B that is equivalent to the outer diameter A of the tip 13 of the tapered shape 15. The outer diameter A of the tip 13 of the tapered shape 15 is approximately the same as the inner diameter of the hose 7.

[0018] The inner diameter C in the range X from the opening of the large-diameter section 25 to partway down the small-diameter section 21 is smaller than the inner diameter of the nozzle 20 (corresponding to the outer diameter A). Due to this change in inner diameter (restriction), when cooling water flows from the hose 7 to the nozzle 20, a pressure loss occurs compared to when the flow rate adjustment mechanism 20 is not present.

[0019] Within the flow rate adjustment mechanism 20 (within the small diameter section 21 in this embodiment), a throttling section 22 is formed to reduce the inner diameter dimension in order to generate further pressure loss. The throttling section 22 is formed in the range Y opposite to the range X in the small diameter section 21. The throttling section 22 has an inner diameter dimension D that is smaller than the inner diameter dimension C of range X. The stepped section 23 between range X and range Y is formed in a tapered shape that is inclined so that the radially outer portion is located closer to range X. The difference between the inner diameter dimensions C and D is greater than the difference between the inner diameter dimension C and the inner diameter dimension of the nozzle 20, resulting in a larger pressure loss.

[0020] The flow rate adjustment mechanism 20 has internal diameter dimensions C and D determined to match the pressure loss required for the nozzle 20 to which it is attached. The flow rate adjustment mechanism 20 reduces the flow rate by generating pressure loss when cooling water flows from the tip side 13 to the base side 14 of the nozzle 20. In addition, pressure loss also occurs when cooling water flows from the base side 14 to the tip side 13 of the nozzle 20, compared to when the flow rate adjustment mechanism 20 is not present.

[0021] The mounting structure of the flow rate adjustment mechanism 20 will be described below with reference to Figures 5 and 6. First, the flow rate adjustment mechanism 20 is inserted into the nozzle 20 in accordance with the direction of the cooling water flow F (arrow in the figure). The flow rate adjustment mechanism 20 is inserted into the nozzle 20 with the large diameter portion 25 located on the upstream side of the flow direction F and the small diameter portion 21 located on the downstream side. If the flow rate adjustment mechanism 20 is inserted into the nozzle 20 with a holding force due to the clamping force, the flow rate adjustment mechanism 20 may also be used with the large diameter portion 25 located on the downstream side of the flow direction F and the small diameter portion 21 located on the upstream side.

[0022] Next, connect the hose 7 to the nozzle 20. Since the large-diameter portion 25 of the flow rate adjustment mechanism 20 has the same diameter as the tip of the nozzle 20, the large-diameter portion 25 does not obstruct the attachment of the hose 7. When connecting the hose 7 to the nozzle 20, a hose clamp may be used if necessary.

[0023] When the flow rate adjustment mechanism 20 is inserted into the nozzle 20 and cooling water is circulated through the cooling water piping, the internal throttling section 22 generates a pressure loss as the cooling water passes through the flow rate adjustment mechanism 20. This makes it possible to adjust the flow rate at the nozzle 20 to which the flow rate adjustment mechanism 20 is attached. For example, even if the multiple flow paths leading to each of the multiple heat sinks 5 (objects to be cooled) have different lengths, the flow rate can be easily balanced.

[0024] Furthermore, since the flow rate adjustment mechanism 20 only needs to be inserted into the nozzle 20, it becomes unnecessary to install a flow rate adjustment valve and flow meter in the water cooling path, thus saving space and simplifying the process. In addition, it eliminates the need for a separate flow rate adjustment process and can be easily applied to existing water cooling paths by sharing piping.

[0025] Furthermore, by preparing multiple flow rate adjustment mechanisms 20 with different inner diameters C and D in advance, and appropriately swapping these multiple flow rate adjustment mechanisms, it becomes possible to adjust the resulting pressure loss. For this reason, the flow rate adjustment structure using the flow rate adjustment mechanism 20 can be applied to various types of water cooling paths.

[0026] As described above, the water cooling device of the power converter 1 in the embodiment is detachably inserted into the fitting 20 for pipe connection in the water cooling path of the power converter 1, and is equipped with a flow rate adjustment mechanism 20 that narrows the flow path diameter in the fitting 20, thereby facilitating flow rate adjustment, eliminating the need for valves and flow meters to save space, and allowing various water cooling paths to be configured by replacing the flow rate adjustment mechanism 20.

[0027] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0028] 1...Power conversion device (equipment) 9...Collection piping (water cooling route) 12...Fucet 20...Flow rate control mechanism

Claims

1. A water cooling device for a power converter, which is detachably inserted into a fitting for pipe connection in the water cooling path of the power converter and is equipped with a flow rate adjustment mechanism that narrows the diameter of the flow path in the fitting.

2. A flow rate adjustment mechanism for a water cooling system, which is detachably inserted into a fitting for pipe connection in the water cooling path of the equipment, and which restricts the flow path diameter in the fitting.

3. A method for adjusting the flow rate of a water cooling device, comprising a flow rate adjustment mechanism that is detachably inserted into a fitting for connecting piping in the water cooling path of the device and narrows the flow path diameter in the fitting, wherein multiple flow rate adjustment mechanisms are set with different inner diameters, and one of the multiple flow rate adjustment mechanisms is selected and attached to the fitting.

Images