Power conversion device

Abstract

To provide a power conversion device that has improved estimation accuracy, is space-saving, and involves a reduced number of sensors.SOLUTION: A power conversion device includes: circuitry that converts between DC power and AC power; a circuit board including the circuitry; a cooling flow channel that cools the circuitry and the circuit board; and a temperature sensor that is disposed on the circuit board and measures the temperature of a coolant that flows in the cooling flow channel by making thermal connection to the cooling flow channel. The circuit board includes a slit, which is a space penetrating in a thickness direction between the temperature sensor and the circuitry in a plane direction of the circuit board, and a copper pattern provided between the slit and the temperature sensor in the plane direction of the circuit board.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a power conversion device. [Background technology]

[0002] In power conversion devices, component temperatures are observed to determine whether protective operation is required. Because this determination is based on sensor measurements or estimated values, there is a demand for improved sensor measurement accuracy. For example, Patent Document 1 below discloses a configuration in which a sensor 32 disposed on a substrate 31 measures the temperature of a case 11, which is composed of a base 13, a wall 14, etc., to indirectly monitor the temperature of a refrigerant flowing through a flow path R. With this configuration, the recessed portion of the wall and the sensor on the substrate face each other, thereby positioning the sensor closer to the case and bringing the ambient temperature around the sensor closer to the case, thereby improving measurement accuracy. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-107755 Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the technology described in Patent Document 1, an increase in the number of sensors and the like as estimation accuracy improves will pose a problem of increased space and components. [Means for solving the problem]

[0005] The power conversion device includes a circuit body that converts DC power and AC power, a circuit board having the circuit body, a cooling flow path that cools the circuit body and the circuit board, and a temperature sensor that is arranged on the circuit board and is thermally connected to the cooling flow path to measure the temperature of a refrigerant circulating within the cooling flow path, and the circuit board has a slit that is a space that penetrates the thickness direction between the temperature sensor and the circuit body in the planar direction of the circuit board, and a copper pattern that is arranged between the slit and the temperature sensor in the planar direction of the circuit board. [Effects of the Invention]

[0006] It is possible to provide a power conversion device that achieves improved estimation accuracy, space saving, and a reduced number of sensors. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is an overall perspective view of a power conversion device according to an embodiment of the present invention; [Figure 2] 1 is a cross-sectional view of a power converter according to an embodiment of the present invention; [Figure 3] Plan view of the circuit board in Figure 2 [Figure 4] 3 is a cross-sectional view illustrating heat transfer in the power conversion device of FIG. 2. [Figure 5] FIG. 3 is a plan view illustrating heat transfer in the power conversion device of FIG. 2. [Figure 6] 3 is a cross-sectional view illustrating heat transfer in space in the power conversion device of FIG. 2. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (One embodiment and overall configuration) (Figure 1) The power conversion device 1 includes a circuit board 100 and a cooling channel 200. The cooling channel 200 includes an upper channel 200a and a lower channel 200b. The circuit board 100 is disposed between the upper channel 200a and the lower channel 200b in the thickness direction.

[0011] The upper surface flow path 200a is conduit-connected to a flow path pipe 201, which serves as an inlet for the coolant, and a flow path pipe 203, which connects the upper surface flow path 200a and the lower surface flow path 200b. The lower surface flow path 200b is conduit-connected to the flow path pipe 203 and a flow path pipe 205, which serves as an outlet for the coolant. This allows the coolant to flow through the upper surface flow path 200a and the lower surface flow path 200b, thereby cooling the circuit board 100.

[0012] (Fig. 2, Fig. 3) The circuit board 100 has a circuit body 101, slits 104, and a plurality of copper patterns 105. The copper pattern 105 may be provided as a single unit on the circuit board 100. The upper surface flow path 200a and the lower surface flow path 200b are provided on the surfaces of the circuit board 100, facing each other.

[0013] The circuit body 101 is a component that has the function of converting DC power and AC power and generates heat during power conversion. The circuit body 101 is disposed in a through-hole that penetrates the circuit board 100 in the thickness direction. Furthermore, both sides of the circuit body 101 in the thickness direction of the circuit board 100 are thermally connected to the upper surface flow path 200a and the lower surface flow path 200b, respectively, via an insulating and heat-transfer member 111 that has insulating and heat-transfer functions. Furthermore, the circuit body 101 is connected to the circuit board 100 via a lead frame 112. Although not shown in the figure, a plurality of circuit bodies 101 are disposed on the circuit board 100 in the long side direction of the cooling flow path 200 (the left-right direction in the drawing).

[0014] The temperature sensor 102 is disposed on the circuit board 100 and is thermally connected to the cooling flow path 200 (upper surface flow path 200a) via the insulating heat transfer member 111. By being thermally connected to the cooling flow path 200, the temperature sensor 102 measures the temperature of the refrigerant flowing through the cooling flow path 200 and measures the temperature change.

[0015] The temperature sensor 102 may measure the temperature of a DC capacitor (not shown) or the like, in addition to measuring the temperature of the refrigerant for the purpose of protecting the power conversion device 1. Furthermore, a value measured by one temperature sensor 102 may be used to estimate the temperature of each component.

[0016] The position of the temperature sensor 102 on the circuit board 100 is preferably on the upstream side of the cooling flow path 200 relative to the position of the circuit body 101, particularly a position closer to the refrigerant inlet (flow path pipe 201 in FIG. 1). This not only makes the temperature sensor 102 less susceptible to the thermal influence of the circuit body 101, etc., but also contributes to determining whether or not an appropriate protective operation of the power conversion device 1 is necessary, because the temperature of the refrigerant measured by the temperature sensor 102 is a temperature before it is influenced by the heat generated by the circuit body 101, etc.

[0017] Slit 104 is a space provided between temperature sensor 102 and circuit body 101 in the planar direction of circuit board 100, penetrating the thickness direction of circuit board 100. Multiple copper patterns 105 are provided between slit 104 and temperature sensor 102 in the planar direction of circuit board 100. Copper patterns 105 are also provided extending in the thickness direction of circuit board 100.

[0018] 5, the length of the slit 104 and the copper pattern 105 in the plane short side direction of the circuit board 100 is the same as the length of the circuit body 101 in the plane short side direction of the circuit board 100. Note that, in order to further reduce the effect of heat from the circuit body 101 on the copper pattern 105 and the temperature sensor 102, the length of the slit 104 and the copper pattern 105 in the plane short side direction of the circuit board 100 may be set to be greater than the length of the circuit body 101 in the plane short side direction of the circuit board 100.

[0019] The heat shielding member 106 is provided between the slit 104 and the temperature sensor 102 in the planar direction of the circuit board 100. The heat shielding member 106 is disposed on the same surface of the circuit board 100 as the surface on which the temperature sensor 102 is mounted, and is thermally connected to the upper flow path 200a. The heat shielding member 106 is provided on the circuit board 100 and is thermally connected to the copper pattern 105. The temperature sensor 102 is provided at the same position in the thickness direction as the copper pattern 105 of the circuit board 100.

[0020] Instead of providing the heat-shielding member 106, a heat-shielding portion formed by the unevenness of the surface of the upper flow path 200a may be provided at a position between the slit 104 and the temperature sensor 102 in the planar direction, and the heat-shielding portion may be thermally connected to the copper pattern 105. By having such a heat-shielding structure, it is not necessary to prepare a separate component, which contributes to cost reduction.

[0021] The heat transfer member 107 is provided at a position overlapping in the thickness direction with the copper pattern 105 of the circuit board 100, and is provided on the surface of the circuit board 100 opposite to the surface on which the heat shielding member 106 is provided. As a result, the copper pattern 105 is thermally connected to the lower flow path 200b via the heat transfer member 107. With this configuration, the cooling flow path 200 cools the circuit body 101 and the circuit board 100. The heat transfer member 107 may be insulating.

[0022] (Fig. 4, Fig. 5) First heat 300 generated from circuit body 101 due to power conversion is transferred in circuit board 100. Circuit board 100 has slits 104, which reduces the amount of heat transferred to copper pattern 105 and temperature sensor 102.

[0023] Second heat 301, which is heat obtained by reducing first heat 300 by slits 104, is transferred to copper pattern 105. Of second heat 301 transferred to copper pattern 105, third heat 302, which is a portion of the heat, is transferred in the thickness direction of circuit board 100, and fourth heat 303, which is heat other than third heat 302, is transferred in the longitudinal direction of circuit board 100.

[0024] Since the copper pattern 105 is provided so as to extend in the thickness direction of the circuit board 100, the third heat 302 is transferred in the thickness direction of the circuit board 100 and dissipated to the upper flow path 200a via the heat shielding member 106, and the third heat 302 is dissipated to the lower flow path 200b via the heat transfer member 107. In this way, the heat generated from the circuit body 101 is reduced and dispersed, thereby reducing the effect of heat transfer on the temperature sensor 102.

[0025] (Figure 6) In addition to the above-described first heat 300, the heat generated from the circuit body 101 also includes radiant heat 304 that is transferred through the space within the power conversion device 1. Such radiant heat 304 is thermally shielded by the heat shielding member 106, and is dissipated from the heat shielding member 106 to the cooling flow path 200 along the same direction as the third heat 302 (FIG. 4). This reduces the heat transfer from the circuit body 101 to the temperature sensor 102.

[0026] Furthermore, the present invention is configured so that the placement of the temperature sensor 102 can be completed within the area on the circuit board 100, thereby suppressing an increase in the number of components and wiring, and an increase in the space required for installing the sensor, thereby reducing costs.

[0027] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0028] (1) A power conversion device 1 includes a circuit body 101 that converts DC power and AC power, a circuit board 100 having the circuit body 101, a cooling channel 200 that cools the circuit body 101 and the circuit board 100, and a temperature sensor 102 that is disposed on the circuit board 100 and is thermally connected to the cooling channel 200 to measure the temperature of a coolant flowing through the cooling channel 200, wherein the circuit board 100 has a slit 104 that is a space penetrating the thickness direction between the temperature sensor 102 and the circuit body 101 in the planar direction of the circuit board 100, and a copper pattern 105 that is provided between the slit 104 and the temperature sensor 102 in the planar direction of the circuit board 100. By doing so, a power conversion device 1 can be provided that achieves improved estimation accuracy, space saving, and a reduced number of sensors.

[0029] (2) The temperature sensor 102 is disposed on the circuit board 100 at a position upstream of the cooling flow path 200 relative to the position of the circuit body 101. This arrangement makes the temperature sensor 102 less susceptible to the thermal influence of the circuit body, etc., which contributes to determining whether or not an appropriate protective operation of the power conversion device 1 is necessary.

[0030] (3) The copper pattern 105 is provided so as to extend in the thickness direction of the circuit board 100. This allows heat from the circuit body 101 to be dissipated to the upper surface flow path 200a and the lower surface flow path 200b.

[0031] (4) In the planar direction of the circuit board 100, a heat shielding member 106 is provided between the slit 104 and the temperature sensor 102, and the heat shielding member 106 is provided on the circuit board 100 and thermally connected to the copper pattern 105, and is also thermally connected to the cooling flow path 200. In this way, heat from the circuit body 101 can be dissipated to the upper surface flow path 200a and the lower surface flow path 200b.

[0032] (5) The cooling flow path 200 has an upper surface flow path 200a and a lower surface flow path 200b, and the upper surface flow path 200a and the lower surface flow path 200b are provided opposite to each other on the surface of the circuit board 100. The heat shielding member 106 is thermally connected to the upper surface flow path 200a, and the copper pattern 105 is thermally connected to the lower surface flow path 200b via the heat transfer member 107. In this way, heat from the circuit body 101 can be dissipated to the upper surface flow path 200a and the lower surface flow path 200b.

[0033] (6) The cooling flow path 200 has a heat shield between the slit 104 and the temperature sensor 102, and the heat shield is thermally connected to the copper pattern 105. This contributes to cost reduction.

[0034] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted. [Explanation of symbols]

[0035] 1 Power conversion device 100 Circuit Boards 101 Circuit body 102 Temperature Sensor 104 Slit 105 Copper Pattern 106 Heat shielding member 107 Heat transfer material 111 Insulating and heat-transferring materials 112 Lead Frame 200 Cooling Channel 200a Upper flow channel 200b Bottom channel 201 Flow pipe 203 Flow pipe 205 Flow pipe 300 first fever 301 Second fever 302 Third fever

Claims

1. a circuit body that converts DC power and AC power; a circuit board having the circuit body; a cooling channel for cooling the circuit body and the circuit board; a temperature sensor disposed on the circuit board and thermally connected to the cooling channel to measure a temperature of the coolant flowing through the cooling channel; The circuit board has a slit, which is a space provided between the temperature sensor and the circuit body in a planar direction of the circuit board and penetrates the board in a thickness direction, and a copper pattern provided between the slit and the temperature sensor in the planar direction of the circuit board. Power conversion device.

2. The temperature sensor is disposed on the circuit board at a position upstream of the cooling flow path relative to the position of the circuit body. The power conversion device according to claim 1 .

3. The copper pattern is provided so as to extend in the thickness direction of the circuit board. The power conversion device according to claim 1 .

4. a heat shielding member is provided between the slit and the temperature sensor in a planar direction of the circuit board; The heat shielding member is provided on the circuit board and thermally connected to the copper pattern, and is also thermally connected to the cooling flow path. The power conversion device according to claim 1 .

5. the cooling flow path has an upper surface flow path and a lower surface flow path, the upper surface flow path and the lower surface flow path are provided opposite to each other on the surface of the circuit board, the heat shielding member is thermally connected to the upper surface flow path; The copper pattern is thermally connected to the lower surface flow path via a heat transfer member. The power conversion device according to claim 4.

6. the cooling flow path has a heat shielding portion at a position between the slit and the temperature sensor in a planar direction; The heat shielding portion is thermally connected to the copper pattern. The power conversion device according to claim 1 .

Images