JP2023062891A - Power conversion device and rotary electric machine with the same - Google Patents

Abstract

To provide a power conversion device which can interrupt excess current of a DC circuit.SOLUTION: A power conversion device 300 comprises: a semiconductor element; an interruption mechanism 30 electrically connected with the semiconductor element to interrupt excess current; and a housing part 140 which accommodates the semiconductor element and the interruption mechanism 30, wherein the interruption mechanism 30 is formed of a multilayer substrate 60 having a plurality of conductor layers and a plurality of insulation members, the plurality of conductor layers comprise inner layers as conductor layers formed inside the multilayer substrate 60, the interruption mechanism 30 has a fuse pattern 31 which fuses when the excess current flows, the fuse pattern 31 is formed in the inner layer, and the inside of the housing part 140 is filled with a potting material 150.SELECTED DRAWING: Figure 11

Description

TECHNICAL FIELD The present disclosure relates to a power conversion device and a rotating electric machine having the same.

Patent Literature 1 describes an electric circuit board. A wiring pattern is formed on the electric circuit board to connect the commercial power source and the electric parts. The wiring pattern forms a closed circuit with the commercial power source and electrical components. At least part of the wiring pattern is formed by a wiring pattern thinner than the other part. When an electrical component or a closed circuit is short-circuited, the fine wiring pattern is fused.

JP-A-2000-3662

The technology of Patent Literature 1 is intended for commercial power supplies. Since the commercial power supply is alternating current, there is a current zero point. Therefore, even if an arc discharge occurs after the fine wiring pattern is fused, the arc discharge disappears when the current reaches the zero point, so the current is interrupted.

However, direct current does not have a current zero point. Therefore, when the electric circuit board of Patent Document 1 is applied to a direct-current circuit, arc discharge occurs continuously after the thin wiring pattern melts, and current continues to flow. Therefore, in the electric circuit board of Patent Document 1, there is a problem that the overcurrent of the DC circuit cannot be interrupted.

The present disclosure has been made to solve the problems described above, and aims to provide a power conversion device capable of interrupting an overcurrent in a DC circuit, and a rotating electric machine including the same.

A power conversion device according to the present disclosure includes a semiconductor element, a blocking mechanism that is electrically connected to the semiconductor element and blocks an overcurrent, and a casing that houses the semiconductor element and the blocking mechanism, The blocking mechanism is formed of a multilayer substrate having a plurality of conductor layers and a plurality of insulating members, and the plurality of conductor layers includes an inner layer that is a conductor layer formed inside the multilayer substrate. The breaking mechanism has a fuse pattern that is fused when the overcurrent flows, the fuse pattern is formed in the inner layer, and a first resin member is provided inside the casing. is filled.
A rotating electric machine according to the present disclosure includes a power conversion device according to the present disclosure, a rotor shaft, a rotor rotating integrally with the rotor shaft, a stator disposed radially outside the rotor, and a rotating electric machine body having a housing that covers the rotor and the stator.

Advantageous Effects of Invention According to the present disclosure, overcurrent in a DC circuit can be interrupted.

2 is a circuit diagram showing an electric circuit of the rotating electric machine according to Embodiment 1; FIG. 1 is a plan view showing a configuration of a power converter according to Embodiment 1; FIG. 1 is a plan view showing a configuration of a power converter according to Embodiment 1; FIG. 1 is a cross-sectional view showing a configuration of a rotating electric machine according to Embodiment 1; FIG. FIG. 2 is a plan view showing the configuration of the cutoff mechanism of the power converter according to Embodiment 1; FIG. 2 is a plan view showing the configuration of the cutoff mechanism of the power converter according to Embodiment 1; FIG. 2 is a plan view showing the configuration of the cutoff mechanism of the power converter according to Embodiment 1; FIG. 2 is a plan view showing the configuration of the cutoff mechanism of the power converter according to Embodiment 1; FIG. 2 is a plan view showing the configuration of the cutoff mechanism of the power converter according to Embodiment 1; FIG. 2 is a plan view showing the configuration of the cutoff mechanism of the power converter according to Embodiment 1; FIG. 6 is a cross-sectional view showing the XI-XI cross section of FIG. 5; 5 is a graph showing actual measurement results of arc discharge voltage when the fuse pattern is arranged in the inner layer of the multilayer substrate and when the fuse pattern is arranged in the outer layer of the multilayer substrate; FIG. 11 is a cross-sectional view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 1-1 of Embodiment 1; FIG. 10 is a cross-sectional view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 1-2 of Embodiment 1; FIG. 10 is a cross-sectional view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 1-3 of Embodiment 1; FIG. 10 is a plan view showing a main part of a cutoff mechanism of a power conversion device according to Modification 1-4 of Embodiment 1; FIG. 10 is a plan view showing a main part of a cutoff mechanism of a power conversion device according to Modification 1-4 of Embodiment 1; FIG. 10 is a plan view showing a main part of a cutoff mechanism of a power conversion device according to Modification 1-4 of Embodiment 1; FIG. 10 is a plan view showing a main part of a cutoff mechanism of a power conversion device according to Modification 1-4 of Embodiment 1; FIG. 8 is a plan view showing the configuration of a cutoff mechanism of the power conversion device according to Embodiment 2; FIG. 8 is a plan view showing the configuration of a cutoff mechanism of the power conversion device according to Embodiment 2; FIG. 8 is a plan view showing the configuration of a cutoff mechanism of the power conversion device according to Embodiment 2; FIG. 8 is a plan view showing the configuration of a cutoff mechanism of the power conversion device according to Embodiment 2; FIG. 8 is a plan view showing the configuration of a cutoff mechanism of the power conversion device according to Embodiment 2; FIG. 8 is a plan view showing the configuration of a cutoff mechanism of the power conversion device according to Embodiment 2; FIG. 21 is a sectional view showing the XXVI-XXVI section of FIG. 20; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-1 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-1 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-1 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-1 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-1 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-1 of Embodiment 2; FIG. 28 is a sectional view showing the XXXIII-XXXIII section of FIG. 27; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-2 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-2 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-2 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-2 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-2 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-2 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-3 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-3 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-3 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-3 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-3 of Embodiment 2; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 2-3 of Embodiment 2; FIG. 11 is a cross-sectional view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 3; FIG. 12 is a cross-sectional view showing the configuration of a cutoff mechanism of a power conversion device according to Modification 3-1 of Embodiment 3; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 4; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 4; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 4; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 4; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 4; FIG. 11 is a plan view showing the configuration of a cutoff mechanism of a power conversion device according to Embodiment 4; FIG. 20 is a plan view showing a configuration of a cutoff mechanism of a power conversion device according to Modification 4-1 of Embodiment 4; FIG. 20 is a plan view showing a configuration of a cutoff mechanism of a power conversion device according to Modification 4-1 of Embodiment 4; FIG. 20 is a plan view showing a configuration of a cutoff mechanism of a power conversion device according to Modification 4-1 of Embodiment 4; FIG. 20 is a plan view showing a configuration of a cutoff mechanism of a power conversion device according to Modification 4-1 of Embodiment 4; FIG. 20 is a plan view showing a configuration of a cutoff mechanism of a power conversion device according to Modification 4-1 of Embodiment 4; FIG. 20 is a plan view showing a configuration of a cutoff mechanism of a power conversion device according to Modification 4-1 of Embodiment 4;

Embodiment 1.
A power conversion device according to Embodiment 1 and a rotating electric machine including the same will be described. A rotating electrical machine according to the present embodiment is mounted in, for example, an electric vehicle (EV) or a hybrid vehicle. Hybrid vehicles include HEVs (Hybrid Electric Vehicles) and PHEVs (Plug-in Hybrid Electric Vehicles).

FIG. 1 is a circuit diagram showing an electric circuit of a rotating electrical machine according to this embodiment. 2 and 3 are plan views showing the configuration of the power converter according to the present embodiment. FIG. 2 shows a state in which the cover 130 and the control board 124 are removed from the power conversion device 300. As shown in FIG. FIG. 3 shows a state where the cover 130 is removed from the power conversion device 300. As shown in FIG. FIG. 4 is a cross-sectional view showing the configuration of the rotating electric machine according to the present embodiment.

<Rotating electric machine 1000>
The rotating electrical machine 1000 includes a power conversion device 300 and a rotating electrical machine body 200, as shown in FIG. Hereinafter, the direction along the rotor shaft 4 of the rotary electric machine main body 200 may be referred to as the "axial direction". A direction along the radius of the rotor shaft 4 in a cross section perpendicular to the axial direction may be referred to as a "radial direction".

The power conversion device 300 is arranged in parallel with the rotary electric machine body 200 in the axial direction. The power conversion device 300 is arranged on the side opposite to the load side of the rotary electric machine body 200 in the axial direction. The power conversion device 300 and the rotary electric machine body 200 are integrated. The power conversion device 300 is configured to supply electric power to the rotary electric machine body 200 using a battery as a power source.

When rotating electrical machine 1000 is mounted in a hybrid vehicle, rotating electrical machine body 200 operates as a motor that drives an internal combustion engine (not shown) or as a generator that is driven by the internal combustion engine to generate power. A rotating electric machine 1000 according to the present embodiment is configured as a starting rotating electric machine for an internal combustion engine. A mounting portion (not shown) is provided in the housing 10 that is a housing for the main body portion 200 of the rotary electric machine. The rotary electric machine 1000 is firmly fixed to the vehicle body or internal combustion engine of the vehicle with bolts via the mounting portion.

<Rotating electric machine body 200>
The rotary electric machine body 200 includes a rotor shaft 4 , a rotor 6 , a stator 3 and a housing 10 . The rotor 6 is fixed to the rotor shaft 4 and rotates together with the rotor shaft 4 . The rotor 6 has a field winding 5 . The stator 3 is arranged radially outside the rotor 6 . A housing 10 covers the rotor 6 and the stator 3 .

The stator 3 includes a stator core 3a and stator windings 3b attached to the stator core 3a. A housing 10 has a front bracket 1 and a rear bracket 2 . The front bracket 1 is a bracket provided on the load side. The rear bracket 2 is a bracket provided on the anti-load side. The front bracket 1 and the rear bracket 2 are formed in a bowl shape using a metal material such as iron.

An end of the rotor shaft 4 protrudes from the front bracket 1 to one side in the axial direction. A pulley 9 is attached to the end of the rotor shaft 4 . A belt (not shown) is wound around the pulley 9 . The rotary electric machine body 200 is connected to a crankshaft (not shown) of the internal combustion engine via a pulley 9 and a belt. The rear bracket 2 and the vehicle body are electrically connected via the stator core 3a and the front bracket 1. As shown in FIG. In the axial direction of the rotary electric machine body 200, the one axial side where the front bracket 1 is provided is the front side, and the other axial side where the rear bracket 2 is provided is the rear side.

The rotor shaft 4 is rotatably supported by the housing 10 with a front side bearing 71 and a rear side bearing 72 . The front side bearing 71 is provided on the front bracket 1 . The rear side bearing 72 is provided on the rear bracket 2 .

The stator core 3 a is sandwiched from both sides in the axial direction by the rear end of the front bracket 1 and the front end of the rear bracket 2 and fixed to the housing 10 . The inner peripheral surface of the stator 3 and the outer peripheral surface of the rotor 6 face each other in the radial direction of the rotary electric machine body 200 with a predetermined air gap therebetween.

The rotor 6 has a first cooling fan 73 and a second cooling fan 74 . The first cooling fan 73 is fixed to the front end face of the rotor 6 . The second cooling fan 74 is fixed to the rear end face of the rotor 6 . The first cooling fan 73 and the second cooling fan 74 rotate together with the rotor 6 .

The front bracket 1 is provided with a first air intake port 11 a for sucking the cooling air into the rotary electric machine main body 200 . The first intake port 11a penetrates the wall of the front bracket 1 on the front side. A plurality of first intake ports 11 a are provided around the rotor shaft 4 .

The rear bracket 2 is provided with a second air intake port 11b that draws the cooling air into the main body 200 of the rotary electric machine. The second intake port 11b penetrates the wall of the rear bracket 2 on the rear side. A plurality of second intake ports 11 b are provided around the rotor shaft 4 .

The front bracket 1 is provided with a first exhaust port 12a for discharging the cooling air from the inside of the rotary electric machine main body 200 to the outside. The first exhaust port 12 a penetrates the radial side wall of the front bracket 1 .

The rear bracket 2 is provided with a second exhaust port 12b for discharging the cooling air from the inside of the rotary electric machine body 200 to the outside. The second exhaust port 12b penetrates the radial side wall of the rear bracket 2 .

The first intake port 11a and the first exhaust port 12a communicate with each other via a first ventilation passage R1. The first air passage R1 is formed between the rear-side surface of the front-side wall of the front bracket 1 and the front-side end surface of the rotor 6 . The first cooling fan 73 is arranged in the first ventilation passage R1.

The outside of rotating electric machine 1000 and second intake port 11b communicate with each other via second air passage R2. Second ventilation path R2 is formed between power converter 300 and rear bracket 2 .

The second intake port 11b and the second exhaust port 12b communicate with each other via a third air passage R3. The third ventilation path R3 is formed between the front side surface of the rear side wall of the rear bracket 2 and the rear side end surface of the rotor 6 . The second cooling fan 74 is arranged in the third ventilation passage R3.

When the first cooling fan 73 rotates, the first cooling air W1 is drawn from the outside of the front bracket 1 into the first intake port 11a. The first cooling air W1 sucked into the first intake port 11a passes through the first ventilation passage R1 and is discharged to the outside of the rotary electric machine main body 200 through the first exhaust port 12a.

When second cooling fan 74 rotates, second cooling air W2 is drawn into second air passage R2 from the outside of rotating electric machine 1000 . The second cooling air W2 sucked into the second ventilation passage R2 flows into the third ventilation passage R3 through the second intake port 11b, and is discharged to the outside of the rotary electric machine main body 200 through the second exhaust port 12b. be done.

<Power conversion device 300>
As shown in FIG. 2, the power converter 300 includes a stator power semiconductor module 121, a smoothing capacitor 122, a filter capacitor 126, a filter coil 127, and a housing 140 that accommodates these components. The power conversion device 300 includes a control board 124 as shown in FIG. The control board 124 is composed of a multilayer board. The field power semiconductor module 120 is mounted on the control board 124 . The control board 124 is configured to control the stator power semiconductor module 121 and the field power semiconductor module 120 .

As shown in FIG. 4, the power conversion device 300 includes a brush 100 and a rotation sensor 110 outside the casing 140. As shown in FIG. The brushes 100 supply power to the rotor 6 . The rotation sensor 110 detects rotation of the rotor 6 .

The stator power semiconductor module 121, the field power semiconductor module 120, the smoothing capacitor 122, the filter capacitor 126, and the filter coil 127 constitute a power circuit section. The smoothing capacitor 122, filter capacitor 126, filter coil 127, brush 100, and rotation sensor 110 are each configured as a control component. The smoothing capacitor 122, the filter capacitor 126, the filter coil 127, the brushes 100, and the rotation sensor 110, together with the stator power semiconductor module 121 and the field power semiconductor module 120, control power supplied to the rotating electrical machine body 200. used for

The stator power semiconductor module 121 includes an upper arm power semiconductor switching element 171 and a lower arm power semiconductor switching element 172, as shown in FIG. The upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 are power semiconductor elements. The upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 control power supply to the stator winding 3b.

The field power semiconductor module 120 includes an upper arm power semiconductor switching element 171 and a lower arm power semiconductor switching element 172 . The upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 are power semiconductor elements. The upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 control power supply to the field winding 5 .

The field power semiconductor module 120 has four power semiconductor elements. The four power semiconductor elements may be mounted on one field power semiconductor module 120 or may be mounted on each of the four field power semiconductor modules 120 .

The smoothing capacitor 122 smoothes the current flowing through the stator winding 3b. Filter capacitor 126 and filter coil 127 are used as an input filter to suppress noise.

The housing part 140 includes a bottom wall 132 made of metal and side walls 131 made of resin provided along the outer periphery of the bottom wall 132 . The housing part 140 has a rectangular planar shape. The bottom wall 132 is a heat radiating member that radiates heat inside the housing 140 to the outside. Bottom wall 132 functions as a heat sink. The bottom wall 132 is also used as a negative electrode side conductor of the power conversion device 300 as described later. The planar shape of the housing part 140 is not limited to a rectangular shape, and may be another shape.

The cover 130 is fixed to the housing portion 140 by screwing or the like. The cover 130 covers the electrical components housed inside the housing 140 .

Note that when noise suppression is not required in the power conversion device 300, the filter capacitor 126 and the filter coil 127 may not be required. When the voltage applied to the power conversion device 300 is 48 V or more, the noise becomes excessive, so the filter coil 127 is often required.

The configuration in which the field winding 5 and the field power semiconductor module 120 are provided is effective in obtaining a large output in the rotary electric machine body 200 . A permanent magnet or the like may be used in place of the field winding 5 when the rotary electric machine body 200 does not require a large output. In this case, the field power semiconductor module 120 may be unnecessary.

One stator power semiconductor module 121 has power semiconductor switching elements for one phase. When the rotating electrical machine body 200 is a three-phase rotating electrical machine, three power semiconductor modules 121 for stator are provided. The three stator power semiconductor modules 121 are connected in parallel.

In the present embodiment, since the rotating electrical machine body 200 is a three-phase rotating electrical machine, as shown in FIGS. 1 and 2, U-phase power semiconductor modules 121U, V A phase power semiconductor module 121V and a W-phase power semiconductor module 121W are provided.

If the rotary electric machine body 200 has six phases, six power semiconductor modules 121 for stator are provided. When one stator power semiconductor module 121 includes power semiconductor switching elements for two phases, three stator power semiconductor modules 121 are provided. When one stator power semiconductor module 121 includes power semiconductor switching elements for three phases, two stator power semiconductor modules 121 are provided.

Each of U-phase power semiconductor module 121U, V-phase power semiconductor module 121V, and W-phase power semiconductor module 121W has a configuration in which upper arm power semiconductor switching element 171 and lower arm power semiconductor switching element 172 are connected in series. are doing. A three-phase bridge circuit is configured by the U-phase power semiconductor module 121U, the V-phase power semiconductor module 121V, and the W-phase power semiconductor module 121W. Each of the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 has, for example, a configuration in which an FET (Field Effect Transistor) and a diode are connected in parallel.

In each of U-phase power semiconductor module 121U, V-phase power semiconductor module 121V, and W-phase power semiconductor module 121W, the connection point between upper arm power semiconductor switching element 171 and lower arm power semiconductor switching element 172 corresponds to It is connected to the AC terminal 175 . Each AC terminal 175 is exposed to the outside of the housing section 140 .

Each AC terminal 175 is connected to each phase winding terminal (not shown) of the stator winding 3 b of the rotary electric machine body 200 via a connection bus bar 211 . The connection bus bar 211 is built in the wiring member 153 . The wiring member 153 is fixed to the rear bracket 2 as shown in FIG. In FIG. 4, wiring portions connecting the AC terminals 175, the connection bus bars 211, and the stator windings 3b are omitted.

In FIG. 1 , to avoid complication of the drawing, reference numeral 175 for the AC terminal and reference numeral 211 for the connection bus bar 211 are attached only to the U-phase AC terminal and connection bus bar 211 .

A signal terminal 176 of each of the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 is connected to the control board 124 . Signal terminal 176 receives a control signal from a control circuit section provided on control board 124 .

In FIG. 1, in order to avoid complication of the drawing, the signal terminal reference numeral 176 is attached only to the signal terminal of the lower arm power semiconductor switching element 172 in the U-phase power semiconductor module 121U. Also, in FIG. 1, connection lines between the signal terminals 176 and the control board 124 are omitted.

The configuration of the stator power semiconductor module 121 will be described. The upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 are soldered to different copper frames. The copper frames are connected by copper plates and aluminum wires. These are sealed with resin.

The configuration of the stator power semiconductor module 121 is not limited to this. The upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 may be soldered to a metal substrate or ceramic substrate coated with insulation. The material of the metal substrate is aluminum, copper, or the like.

The stator power semiconductor module 121 has a heat dissipation surface 177 for dissipating heat generated from the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172, as shown in FIG. A protrusion 143 is formed to protrude from the mounting surface, which is the rear-side surface of the bottom wall 132 . The stator power semiconductor module 121 is mounted such that the heat dissipation surface 177 and the protrusion 143 face each other. As a result, the heat dissipation surface 177 of the stator power semiconductor module 121 is thermally connected to the protrusion 143 .

When the conductive member of the stator power semiconductor module 121 is exposed on the heat dissipation surface 177 , the stator power supply is required to secure a predetermined distance between the heat dissipation surface 177 and the mounting surface of the protrusion 143 . The semiconductor module 121 is mounted on the projecting portion 143 with an insulating heat transfer member interposed therebetween. As the insulating heat transfer member, viscous and fluid grease, gel, adhesive, non-fluid sheet, tape, or the like is used.

When the heat dissipation surface 177 is insulated from each of the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172, not only the insulating heat transfer member but also the conductive heat transfer member can be used. can be used. In this case, it is not necessary to secure a distance between the heat dissipation surface 177 and the mounting surface of the protrusion 143 .

The bottom wall 132 has fins 141 that are a cooling mechanism. The fins 141 are formed on the front-side surface of the bottom wall 132 corresponding to the protrusions 143, and are arranged in the second ventilation path R2. Since the fins 141 are provided, the stator power semiconductor module 121 can be efficiently cooled by the second cooling air W2. When the amount of heat generated by the stator power semiconductor module 121 increases due to the increase in output, a coolant passage may be provided inside the bottom wall 132 to improve the cooling performance of the stator power semiconductor module 121 with the coolant. Thereby, the heat generated from the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 can be effectively transferred to the bottom wall 132 over a wide range. Therefore, the temperature rise of the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 can be suppressed.

The positive terminal 173 of each of the U-phase power semiconductor module 121U, the V-phase power semiconductor module 121V, and the W-phase power semiconductor module 121W, the positive terminal 183 of the field power semiconductor module 120, and the positive side of the filter capacitor 126 The terminal 192 and the positive terminal 195 of the smoothing capacitor 122 are connected to the positive conductor 125, which is a bus bar, as shown in FIG.

A positive terminal 190 , which is a connection terminal of the power converter 300 , is connected to a positive terminal 501 of the battery 500 via a positive cable 503 . Battery 500 is a DC power supply mounted on a vehicle.

The negative terminal 174 of each of the U-phase power semiconductor module 121U, the V-phase power semiconductor module 121V, and the W-phase power semiconductor module 121W, the negative terminal 194 of the filter capacitor 126, and the negative terminal 196 of the smoothing capacitor 122 are , is connected to the bottom wall 132 of the housing portion 140 . A negative terminal 184 of the field power semiconductor module 120 is connected to the bottom wall 132 via the control board 124 .

A negative terminal 191 of the power converter 300 is connected to a negative terminal 502 of the battery 500 via a negative cable 504 . A negative terminal 502 of the battery 500 is connected to the vehicle body. The vehicle body is maintained at ground potential. If the bottom wall 132 and the negative terminal 502 of the battery 500 can be electrically connected through the vehicle body, the negative cable 504 can be omitted.

As shown in FIG. 2, the negative terminal 174 of each of the U-phase power semiconductor module 121U, the V-phase power semiconductor module 121V, and the W-phase power semiconductor module 121W and the bottom wall 132 are fixed by a first screw 179. ing. The negative terminal 184 of the field power semiconductor module 120 and the bottom wall 132 are fixed by a second screw. The negative terminal 196 of the smoothing capacitor 122 and the bottom wall 132 are fixed by a third screw 178 . A negative terminal 194 of the filter capacitor 126 and the bottom wall 132 are fixed by a fourth screw 197 .

The positive conductor 125 is arranged in parallel with the bottom wall 132 . As a result, the planar portion of the positive electrode-side conductor 125 faces the bottom wall 132 . Therefore, the inductance is reduced by having the positive electrode and the negative electrode parallel to each other. Therefore, noise and switching loss can be suppressed.

The field power semiconductor module 120 forms a full bridge circuit using power semiconductor switching elements such as FETs. A positive terminal 185 and a negative terminal 186 on the winding side of the field power semiconductor module 120 are exposed to the outside of the casing 140 . Each of the positive terminal 185 and the negative terminal 186 is connected to a winding terminal (not shown) of the rotor 6 .

If the smoothing capacitor 122 is individually provided for each phase, it is effective in reducing switching noise. For simplicity of construction, the smoothing capacitor 122 may be accommodated in one block, as shown in FIG.

The shorter the wiring distance between the stator power semiconductor module 121 and the smoothing capacitor 122 of each phase, the more effective it is to reduce the inductance. Therefore, the positive terminal 195 of the smoothing capacitor 122 is arranged near the positive terminal 173 of the stator power semiconductor module 121 of each phase. The negative terminal 196 of the smoothing capacitor 122 is arranged near the negative terminal 174 of the stator power semiconductor module 121 of each phase.

A smoothing capacitor 122 absorbs voltage fluctuations and current ripples. As the current ripple is applied to the smoothing capacitor 122, the smoothing capacitor 122 generates heat and its temperature rises. Since the smoothing capacitor 122 deteriorates due to temperature rise, the life of the smoothing capacitor 122 is shortened. In order to suppress deterioration of smoothing capacitor 122 , smoothing capacitor 122 is thermally connected to bottom wall 132 . A plurality of smoothing capacitors 122 may be provided for each phase in consideration of the amount of current ripple, temperature rise, and the like.

The filter coil 127 is configured, for example, by penetrating a part 193 of the positive electrode side conductor 125 through the filter core 123 . The filter core 123 is composed of two U-shaped parts, which are provided with their open sides facing each other. With this configuration, the filter core 123 can be assembled to the positive electrode conductor 125 without cutting the positive electrode conductor 125 . Filter core 123 absorbs the magnetic flux generated in part 193 of positive electrode-side conductor 125 inside filter core 123 . Thereby, noise can be suppressed.

Filter capacitor 126 and filter coil 127 suppress noise. The energization causes the filter capacitor 126 and the filter coil 127 to generate heat and raise their temperatures. As the temperature of the filter capacitor 126 rises, the life of the filter capacitor 126 is shortened. When the temperature of the filter core 123 of the filter coil 127 increases, the inductance decreases due to demagnetization. Filter capacitor 126 and filter coil 127 are thermally connected to bottom wall 132 in order to suppress deterioration due to temperature rise. A plurality of filter capacitors 126 and a plurality of filter coils 127 may be provided in consideration of current, voltage, degree of noise suppression, and the like.

Electronic components (not shown) such as a CPU (Central Processing Unit) are mounted on the control board 124 . The control board 124 includes a control circuit section for controlling on/off of the power semiconductor switching elements of the power circuit section. The control circuit section performs power conversion between the DC power of the battery 500 and the AC power of the stator winding 3b by controlling the on/off of the power semiconductor switching elements, and also controls the field current to the field winding 5. control.

As shown in FIG. 3, a positive electrode pattern (not shown) provided on the control board 124 and a pin terminal 187 provided on the positive electrode side conductor 125 are connected. A negative electrode pattern (not shown) provided on the control board 124 and a support 132 a provided on the bottom wall 132 are connected by a fifth screw 198 . Through these connections, power required for control is supplied from the battery 500 to the control board 124 . The control board 124 may be configured by a printed circuit board. As a result, the pin terminals 187 and the plurality of signal terminals 176 (not shown in FIG. 3) can be connected to the control board 124 at once by jet soldering, thereby reducing the number of man-hours.

The positive electrode side terminal 190 is configured by being press-fitted into a through hole formed in the positive electrode side conductor 125, for example. Alternatively, the positive electrode side terminal 190 may be configured by being press-fitted into an aluminum material insulated from the bottom wall 132 and brought into contact with the positive electrode side conductor 125 of the power conversion device 300 . In this embodiment, as shown in FIG. 2, the positive terminal 190 is press-fitted into a through hole formed at the end of the positive conductor 125 . The negative terminal 191 is press-fitted into the bottom wall 132, for example.

By configuring in this way, the positive electrode side terminal 190, the filter capacitor 126, the stator power semiconductor module 121, the field power semiconductor module 120, the smoothing capacitor 122, and the control Connections to each of the substrates 124 can be made by a single positive conductor 125 . Also, the filter coil 127 can be configured with a single positive electrode side conductor 125 .

Furthermore, by configuring in this way, the connection with each of the negative terminal 191, the filter capacitor 126, the stator power semiconductor module 121, the field power semiconductor module 120, the smoothing capacitor 122, and the control board 124 can be It can be done with a single bottom wall 132 . With this configuration, it is possible to easily configure a small-sized, low-inductance power conversion device 300 without adding wiring or increasing the number of connection man-hours.

In addition, each of the positive terminal 192 of the filter capacitor 126, the positive terminal 173 of the stator power semiconductor module 121, the positive terminal 183 of the field power semiconductor module 120, and the positive terminal 195 of the smoothing capacitor 122, The connection with the positive electrode side conductor 125 may be uniformly performed by welding such as TIG, for example. This allows these connections to be made using the same equipment.

In this embodiment, the number of parts is reduced by using the bottom wall 132 as the negative electrode side conductor of the power conversion device 300 . However, the same effect can be obtained even if the negative electrode side conductor is composed of a wiring material independent of the bottom wall 132 . In this case, welding such as TIG is effective for connecting each part and the negative electrode side conductor. Moreover, in this case, the filter coil 127 can be attached to the negative wiring, so that the number of configuration patterns of the filter circuit can be increased. Furthermore, the connection between the negative electrode side conductor and the control board 124 can be performed by jet soldering. Therefore, the negative conductor can be connected to the control board 124 at the same time as the pin terminal 187 and the like are connected to the control board 124 .

The power conversion device 300 includes a potting material 150 filled inside the casing 140, as shown in FIG. The potting material 150 is a resin member that seals the inside of the housing section 140 . The potting material 150 is filled so that the electrical components provided inside the housing 140 are buried. Since the electrical components are sealed with the potting material 150, the waterproofness and dustproofness of the power conversion device 300 can be improved, and the vibration resistance and heat transfer property of the power conversion device 300 can be improved. Note that the potting material 150 may be filled only around the electrical components that generate a large amount of heat. That is, the potting material 150 may be filled in the entire inside of the housing portion 140 or may be partially filled in the inside of the housing portion 140 .

For the potting material 150, for example, a resin material having high rigidity and high thermal conductivity is used. Epoxy resin, silicone resin, urethane resin, or the like is used for the potting material 150 . The potting material 150 contains heat conductive filler. The thermal conductivity of the potting material 150 is desirably 0.1 W/(m·K) to 20 W/(m·K). If the potting material 150 is not required to have a high thermal conductivity, the potting material 150 may not contain a thermally conductive filler. If the potting material 150 does not require high rigidity, the potting material 150 may be gel-like or rubber-like.

The brush 100 is provided around the rotor shaft 4 on the rear side of the rear bracket 2 . The brush 100 is mounted on the front side of the bottom wall 132 . A current-carrying part (not shown) electrically connected to the field winding 5 is attached to the rotor shaft 4 . The output of the field power semiconductor module 120 is input to the field winding 5 by contacting the sliding portion of the brush 100 with the current-carrying portion.

<Operation of Rotating Electric Machine 1000>
The operation of rotating electric machine 1000 will be described. Current flows differently between the case where rotating electrical machine main body 200 operates as an electric motor and the case where rotating electrical machine main body 200 operates as a generator. Here, a case where the rotary electric machine body 200 operates as an electric motor will be described.

A current flowing through the stator winding 3b of the rotary electric machine main body 200 passes through the following paths. Current flows from the positive terminal 501 of the battery 500 into the power converter 300 via the positive cable 503 and the positive terminal 190 . In the power conversion device 300, current flows through the stator winding 3b via the filter capacitor 126, the filter coil 127, and the upper arm power semiconductor switching element 171 of the stator power semiconductor module 121 of one phase. .

After that, the current flows to the bottom wall 132 through the lower arm power semiconductor switching element 172 of the stator power semiconductor module 121 of another phase, and through the negative terminal 191 and the negative cable 504 to the negative side of the battery 500 . Return to terminal 502 .

The CPU of the control board 124 calculates a control pattern for on/off controlling the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 based on the information obtained from various sensors. The information obtained from various sensors includes information on the current value detected by a current sensor (not shown), information on at least one of the rotational speed and rotational position of the rotor 6 detected by the rotation sensor 110, and upper arm power. There is temperature information of the semiconductor switching element 171 and the lower arm power semiconductor switching element 172 .

The control circuit section of the control board 124 outputs a control signal based on the calculation result of the CPU to each signal terminal 176 of the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 of each phase.

By controlling the upper arm power semiconductor switching element 171 and the lower arm power semiconductor switching element 172 of each phase, the DC power of the battery 500 is converted into AC power and supplied to the stator winding 3b. As a result, a rotating magnetic field is generated in the stator core 3a, and the rotor 6 rotates. As the rotor 6 rotates, the first cooling fan 73 and the second cooling fan 74 rotate.

When the first cooling fan 73 rotates, the first cooling air W1 is generated. The front side coil end of the stator winding 3b is cooled by the first cooling air W1. When the second cooling fan 74 rotates, the second cooling air W2 is generated. The second cooling air W2 cools the bottom wall 132, the rear bracket 2, the rotor 6, and the rear side coil end of the stator winding 3b. be done.

By cooling the bottom wall 132 , heat generated in the stator power semiconductor module 121 , the smoothing capacitor 122 , the filter capacitor 126 and the filter coil 127 is radiated through the bottom wall 132 . By cooling the rear bracket 2 , the frictional heat generated by the rear side bearing 72 and the heat generated by the stator 3 are radiated via the rear bracket 2 . Heat generated in the field winding 5 is radiated through the rotor 6 by cooling the rotor 6 . These heat dissipations suppress the temperature rise of each component of rotating electric machine 1000 .

<Blocking mechanism 30>
A blocking mechanism 30 is provided on a part of the control board 124 . The cutoff mechanism 30 has a fuse pattern 31 which will be described later. As a result, burning of the field power semiconductor module 120 when a short-circuit current flows through the field power semiconductor module 120 can be suppressed. A specific description will be given below.

In FIG. 1, for example, when a power semiconductor switching element mounted on the field power semiconductor module 120 fails and short-circuits, a short-circuit current flows. Without the interrupting mechanism 30, the function of interrupting the current is lost, so the short-circuit current continues to flow through the field power semiconductor module 120, and the field power semiconductor module 120 burns out.

In FIG. 1 , the cutoff mechanism 30 is provided between the positive terminal 190 and the four power semiconductor elements of the field power semiconductor module 120 . When a short-circuit current flows through the power conversion device 300, the fuse pattern 31 with a small cross-sectional area locally generates heat. When the temperature of the fuse pattern 31 exceeds the melting point, the fuse pattern 31 melts. When the fuse pattern 31 blows, the current path is physically cut off between the positive terminal 190 and the field power semiconductor module 120 . As a result, burning of the field power semiconductor module 120 can be prevented.

The blocking mechanism 30 is formed of a multilayer substrate. For example, the blocking mechanism 30 is formed in a part of the multi-layer board that constitutes the control board 124 . A multilayer board has a plurality of conductor layers and a plurality of insulating members. The conductor layers and the insulating members are alternately laminated. A conductive pattern is formed on each conductor layer. The fuse pattern 31 is one of the conductive patterns. A multilayer substrate has an outer layer, which is a conductor layer formed on the surface of the multilayer substrate, and an inner layer, which is a conductor layer formed inside the multilayer substrate. Multilayer substrates typically have two outer layers and at least one inner layer. The inner layer is sandwiched between two layers of insulating members.

In this embodiment, the blocking mechanism 30 is composed of a multilayer substrate having a six-layer structure. A multilayer substrate having a six-layer structure has six conductor layers. Of the six conductor layers, two conductor layers are outer layers and four conductor layers are inner layers.

5 to 10 are plan views showing the configuration of the cutoff mechanism of the power converter according to the present embodiment. FIG. 5 shows the configuration of the first layer of the multilayer substrate 60. As shown in FIG. Similarly, FIGS. 6 to 10 show the configurations of the second to sixth layers of the multilayer board 60, respectively. The first and sixth layers are outer layers, and the second to fifth layers are inner layers. 11 is a sectional view showing the XI-XI section of FIG. 5. FIG. The vertical direction in FIG. 11 represents the axial direction of the rotating electric machine 1000 . The upper part of FIG. 11 represents the rear side, and the lower part of FIG. 11 represents the front side.

The multilayer substrate 60 has a configuration in which a plurality of base materials 19 as insulating members and a plurality of conductive patterns are alternately laminated without gaps. The multilayer board 60 is, for example, a printed circuit board. The conductive pattern of the outer layer is exposed outside the multilayer substrate 60 . The conductive pattern of the inner layer is surrounded by an insulating member such as the base material 19 and hermetically sealed between the two base materials 19 . A groove may be formed on the surface of the base material 19 and the conductive pattern may be embedded in the groove.

In the present embodiment, multilayer substrate 60 is formed by stacking five substrates 19 . One sheet of base material 19 has a configuration in which conductive patterns are formed on both sides. The remaining four substrates 19 have a configuration in which a conductive pattern is formed only on one surface. Each base material 19 is formed in a rectangular plate shape. Both surfaces of the multilayer substrate 60 are in contact with the potting material 150 without gaps.

The base material 19 is made of any electrically insulating material. The base material 19 is made of, for example, glass fiber reinforced epoxy resin, phenol resin, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), or the like. The base material 19 may be made of, for example, polyethylene terephthalate (PET) or polyimide (PI) film, or may be made of paper made of aramid (wholly aromatic polyamide) fiber. may Also, the base material 19 may be made of a ceramic material such as aluminum oxide (Al ₂ O ₃ ) or aluminum nitride (AlN). The base material 19 should be able to insulate between the layers of the conductive pattern formed on each layer.

<First terminal pattern and second terminal pattern>
As shown in FIGS. 5 to 11, first to sixth layers are provided with a first terminal pattern 21 and a second terminal pattern 22 spaced apart from each other. The first terminal patterns 21 of each layer are arranged to overlap each other when viewed in the normal direction of the substrate surface of the multilayer substrate 60 . The second terminal patterns 22 of each layer are arranged at positions overlapping each other when viewed in the normal direction of the substrate surface of the multilayer substrate 60 . The first terminal pattern 21 and the second terminal pattern 22 are made of copper foil. In this embodiment, both the first terminal pattern 21 and the second terminal pattern 22 are formed in a rectangular plate shape. Each of the first terminal pattern 21 and the second terminal pattern 22 is one of conductive patterns.

A cylindrical through hole 16 is formed in the first terminal pattern 21 . The through holes 16 pass through the multilayer substrate 60 . A plated layer (not shown) is formed on the inner wall of the through hole 16 . The first terminal patterns 21 of each layer are connected to each other through through holes 16 so as to have the same potential. In this embodiment, five through holes 16 are provided in the first terminal pattern 21 of each layer.

A cylindrical through hole 43 is formed in the second terminal pattern 22 . The through holes 43 pass through the multilayer substrate 60 . A plated layer (not shown) is formed on the inner wall of the through hole 43 . The second terminal patterns 22 of each layer are connected to each other through through holes 43 so as to have the same potential. In the present embodiment, one through hole 43 larger than the through hole 16 is provided in the second terminal pattern 22 of each layer.

The first terminal pattern 21 is connected to the field power semiconductor module 120 via a wiring member (eg, wiring pattern or harness) not shown. A pin terminal 187 is inserted into the through hole 43 . The second terminal pattern 22 is connected to the pin terminal 187 by solder 51 . The second terminal pattern 22 is connected to the positive conductor 125 via the pin terminal 187 . Since the blocking mechanism 30 has no directivity, the pin terminal 187 may be inserted into the through hole 16 and the first terminal pattern 21 may be connected to the pin terminal 187 . In this case, the second terminal pattern 22 is connected to the field power semiconductor module 120 .

<Fuse pattern>
The fuse pattern 31 is provided in one of the inner layers of the multilayer substrate 60, that is, the second to fifth layers. The fuse pattern 31 is formed only on the inner layer of the multilayer substrate 60 , for example, on any one of the inner layers of the multilayer substrate 60 . The fuse pattern 31 connects the first terminal pattern 21 and the second terminal pattern 22 .

In this embodiment, fuse pattern 31 is provided in the third layer of multilayer substrate 60 . The fuse pattern 31 is made of copper foil. The fuse pattern 31 is made of the same material as the first terminal pattern 21 and the second terminal pattern 22 .

The fuse pattern 31 has a first terminal-side base portion 33 , a second terminal-side base portion 34 , and a fuse portion 35 . The first terminal side base portion 33 is formed at one end of the fuse pattern 31 . The first terminal side base portion 33 is connected to the first terminal pattern 21 . The second terminal side base portion 34 is formed at the other end of the fuse pattern 31 . The second terminal side base portion 34 is connected to the second terminal pattern 22 . The fuse portion 35 connects between the first terminal side base portion 33 and the second terminal side base portion 34 . The fuse portion 35 is sandwiched between two substrates 19 . Thereby, the fuse portion 35 is sealed inside the multilayer substrate 60 .

The fuse portion 35 is formed in a rectangular plate shape. In the current path, the fuse portion 35 has a cross-sectional area smaller than both the cross-sectional area of the first terminal-side base portion 33 and the cross-sectional area of the second terminal-side base portion 34 . In the current path, the fuse portion 35 has a cross-sectional area smaller than both the cross-sectional area of the first terminal pattern 21 and the cross-sectional area of the second terminal pattern. The fuse portion 35 is a blowout portion that blows out when an overcurrent flows. The resistance value [Ω] of the fuse portion 35 is adjusted by adjusting one or both of the length and cross-sectional area of the fuse portion 35 .

The fuse pattern 31, the first terminal pattern 21, the second terminal pattern 22, the through holes 16, and the through holes 43 are made of a conductive material. For example, the fuse pattern 31, the first terminal pattern 21, the second terminal pattern 22, the through holes 16 and the through holes 43 are made of copper (Cu), silver (Ag), gold (Au), tin (Sn), aluminum (Al ), a copper alloy, a nickel (Ni) alloy, a gold alloy, a silver alloy, a tin alloy, or an aluminum alloy. The fuse pattern 31, the first terminal pattern 21, the second terminal pattern 22, the through holes 16, and the through holes 43 may be made of the same material, or may be made of different materials.

The control board 124 is sealed with a potting material 150 inside the housing section 140 of the power converter 300 . Therefore, the periphery of the blocking mechanism 30 is also sealed with the potting material 150 .

<Fusing due to short-circuit current>
Here, the operation of the fuse pattern 31 and the principle of interrupting the direct current will be described by taking as an example a case where a switching element has a short-circuit failure. When the field power semiconductor module 120 is short-circuited, a short-circuit current flows through the breaking mechanism 30 .

The short circuit current is higher than the current during normal operation. The cross-sectional area of the fuse portion 35 is smaller than the cross-sectional area of the other conductive patterns, and the resistance value of the fuse portion 35 is larger than the resistance values of the other conductive patterns. As a result, the amount of heat generated by the fuse portion 35 becomes greater than that of the other conductive patterns, and the temperature rises locally, causing the fuse portion 35 to melt.

When the fuse portion 35 blows, arc discharge is generated so as to connect the ends of the fuse patterns 31 facing each other across the blown portion. If the current to be interrupted is a direct current, there is no zero point of the current, so even if the fuse portion 35 is blown, arc discharge continues to occur and the current continues to flow. If the current continues to flow, not only the field power semiconductor module 120 but also other electronic components and wiring patterns in the closed circuit will generate heat, which may damage the power converter 300 . Therefore, it is necessary to forcibly reduce the current, create a zero point, and interrupt the arc discharge.

A circuit equation of a closed circuit is represented by Equation (1).
Vin=i×(R+r)+L×di/dt (1)
Here, Vin is the voltage between the positive terminal 190 and the negative terminal 191 . i is the current flowing in the closed circuit. R is the resistance value of the closed circuit excluding the fuse portion 35 . r is the resistance value of the fuse portion 35; However, r after the occurrence of arc discharge is the resistance value of arc discharge. L is the reactance of the closed circuit. t is time.

After the arc discharge occurs, R<<r and can be approximated as (R+r)≈r, so equation (1) can be transformed into equation (2).
di/dt=(Vin−i×r)/L (2)

From equation (2), di/dt on the left side must be negative (di/dt<0) in order to reduce the current. Therefore, it is necessary to make the arc discharge voltage (i×r) higher than the voltage Vin. In order to increase the arc discharge voltage, the arc discharge resistance value r should be increased. Arc discharge resistance value r is generally represented by Equation (3).
r=L/(σ×Ar) (3)
where L is the arc discharge length [m]. σ is electric conductivity [S/m] of arc discharge. Ar is the cross-sectional area [m ² ] of the arc discharge.

From the equation (3), in order to increase the resistance value r of the arc discharge, the length L of the arc discharge can be increased, the diameter of the arc discharge can be decreased to reduce the cross-sectional area Ar, or the electric conduction of the arc discharge The ratio σ should be lowered.

<Comparative example>
As a comparative example, consider a case where a fuse pattern is provided on the outer layer of the substrate. The arc discharge generated in the outer layer of the substrate can be freely deformed in the air. Therefore, the arc discharge diameter is not limited. Therefore, the diameter of the arc discharge is increased, and the cross-sectional area Ar of the arc discharge is increased. Therefore, the arc discharge resistance value r and the arc discharge voltage (i×r) are reduced. Therefore, di/dt in equation (2) becomes positive, and there is a possibility that the current cannot be interrupted.

When the fuse pattern is fused, a fused product containing a conductive material is generated. In the comparative example, since the fuse pattern is provided on the outer layer of the substrate, there is a risk that the melted material will scatter to other circuits and damage the electrical components. Further, when the fuse pattern is provided on the outer layer of the substrate, it is difficult to provide a scattering prevention pattern that covers the fuse pattern. Therefore, electromagnetic noise cannot be shielded during normal circuit operation and during short-circuit breaking, and the electromagnetic noise may adversely affect other electrical components, resulting in malfunction.

A portion of the fuse pattern having a smaller cross-sectional area has a larger resistance value than other patterns, and thus generates a large amount of heat during normal circuit operation. In the comparative example, since this portion is provided on the outside, heat is difficult to diffuse. Therefore, even during normal circuit operation, the temperature of the fuse pattern rises, and there is a risk of damage to the fuse pattern.

<Action of fuse part and potting material>
Therefore, in the present embodiment, the fuse pattern 31 is provided in the inner layer of the multilayer substrate 60 as described above.

FIG. 12 is a graph showing measurement results of arc discharge voltage when the fuse pattern is arranged in the inner layer of the multilayer substrate and when the fuse pattern is arranged in the outer layer of the multilayer substrate. As the length of the fuse portion 35 increases, the arc discharge voltage increases. Also, the arc discharge voltage is higher when the fuse pattern 31 is arranged in the inner layer of the multilayer substrate 60 than in the case where the fuse pattern 31 is arranged in the outer layer of the multilayer substrate 60 .

Since the fuse pattern 31 is arranged in the inner layer of the multilayer substrate 60 , the fuse pattern 31 is surrounded by the base material 19 . Therefore, since the arc discharge is restricted to the space surrounded by the substrate 19, the cross-sectional area Ar of the arc discharge does not increase. In addition, decomposition gas is generated from the substrate 19 by exposing the substrate 19 to the arc discharge. Therefore, the cross-sectional area Ar of the arc discharge becomes smaller than the cross-sectional area of the space surrounded by the substrate 19 due to the ablation effect.

As shown in Equation (3), the arc discharge resistance value r is inversely proportional to the cross-sectional area Ar of the arc discharge. That is, when the cross-sectional area Ar of the arc discharge becomes smaller, the resistance value r of the arc discharge becomes higher and the arc discharge voltage (i×r) becomes higher. Therefore, since di/dt in equation (2) can be made negative, the arc discharge current generated after fusing can be gradually reduced and the current can be interrupted.

It should be noted that as the length L of the arc discharge increases, the resistance value r of the arc discharge increases, as shown in Equation (3). As shown in equation (2), the length of the fuse portion 35 should be set so that the arc discharge voltage (i×r) becomes higher than the voltage Vin and di/dt becomes negative. If the fuse portion 35 is fused, the shape of the fuse portion 35, such as the cross-sectional area and length, can be set to any shape.

Moreover, in the present embodiment, as described above, the potting material 150 covers the periphery of the blocking mechanism 30 . According to this configuration, since the fuse pattern 31 is pressed by the base material 19 and the potting material 150, it is possible to prevent the multilayer substrate 60 from peeling off. Furthermore, since the fuse pattern 31 is surrounded not only by the base material 19 but also by the potting material 150, it is possible to suppress scattering of melted material of the fuse pattern 31 to other circuits.

Further, in the present embodiment, the control board 124 is thermally connected to the housing section 140 via the potting material 150 . That is, the blocking mechanism 30 is thermally connected to the housing 140 via the potting material 150 . Therefore, the heat dissipation of the fuse pattern 31 can be enhanced, and the temperature rise of the fuse pattern 31 can be reduced when the power conversion device 300 normally operates.

Furthermore, a pin terminal 187 is soldered to the through hole 43 . The pin terminals 187 are inserted into the through holes 43 along the thickness direction of the control board 124 . When the Young's modulus of the pin terminals 187 is higher than that of the base material 19, the pin terminals 187 also provide the effect of preventing the multilayer substrate 60 from peeling off. As a result, the arc discharge voltage after fusing is increased, so that the current interrupting effect is improved.

With respect to the voltage Vin applied between the first terminal pattern 21 and the second terminal pattern 22, generally when the applied voltage is 20 V or higher, arc discharge tends to occur, and the effect of interrupting the arc discharge can be easily obtained. . That is, when the voltage applied to the breaking mechanism 30 is a DC voltage of 20 V or more, the arc discharge breaking effect can be easily obtained. Even if the applied voltage is less than 20 V and arc discharge does not occur after fusing, the fuse pattern 31 provided in the inner layer provides an effect of preventing scattering of fusing material.

Although the fuse pattern 31 is formed in the third layer in FIG. 11, it may be formed in any of the second to fifth layers as long as it is formed in the inner layer. For example, when the fuse pattern 31 is provided on the fifth layer close to the housing part 140, the pressing effect by the potting material 150 and the base material 19 is improved, so the peeling prevention effect of the multilayer substrate 60 is improved.

<Modification 1-1>
FIG. 13 is a cross-sectional view showing the configuration of the cutoff mechanism of the power converter according to Modification 1-1 of the present embodiment. FIG. 13 shows a section corresponding to FIG. As shown in FIG. 13 , the inside of the through hole 16 in the blocking mechanism 30 may be filled with a potting material 150 . By filling the inside of the through hole 16 with the potting material 150, the potting material 150 passes through the control board 124 in the thickness direction. In addition, the effect of preventing peeling of the multilayer substrate 60 is exhibited.

If the potting material 150 contains thermally conductive filler, the inner diameter of the through hole 16 is preferably larger than the particle size of the thermally conductive filler. This facilitates filling of the potting material 150 inside the through hole 16 . Since the particle size of the thermally conductive filler is generally several μm to 200 μm, the inner diameter of the through hole 16 is preferably larger than 200 μm.

<Modification 1-2>
FIG. 14 is a cross-sectional view showing the configuration of the cutoff mechanism of the power converter according to Modification 1-2 of the present embodiment. As shown in FIG. 14 , a field power semiconductor module 120 is connected to the first terminal pattern 21 . The field power semiconductor module 120 has terminals 188 . Terminal 188 is connected to first terminal pattern 21 by solder 52 .

The potting material 150 is filled so as to cover the field power semiconductor module 120 . That is, the potting material 150 is formed to have a thickness that covers the field power semiconductor module 120 . Therefore, since the thickness of the potting material 150 covering the upper part of the blocking mechanism 30 can be increased, the effect of preventing peeling of the multilayer substrate 60 is improved.

<Modification 1-3>
FIG. 15 is a cross-sectional view showing the configuration of the cutoff mechanism of the power converter according to Modification 1-3 of the present embodiment. As shown in FIG. 15, power converter 300 may have shield 199 . A shield 199 is arranged to cover the top of the blocking mechanism 30 . The shield 199 overlaps the fuse pattern 31 when viewed in the direction normal to the substrate surface of the multilayer substrate 60 . The shield 199 has a function of shielding electromagnetic noise from the fuse pattern 31 . Shield 199 is supported by potting material 150 .

The shield 199 is made of the same material as the housing section 140 . The stiffness of the shield 199 is higher than the stiffness of the potting material 150 . When the shield 199 is arranged so as to cover the upper portion of the blocking mechanism 30, the effect of preventing peeling of the multilayer substrate 60 is improved. Furthermore, since the heat generated by the fuse pattern 31 during normal operation can be dissipated to the shield 199, the temperature rise of the fuse pattern 31 can be reduced.

<Modification 1-4>
16 to 19 are plan views showing the essential parts of the cutoff mechanism of the power converter according to modification 1-4 of the present embodiment. In the configuration shown in FIG. 7, the fuse portion 35 is formed in a rectangular plate shape. However, the shape of the fuse portion 35 is not limited to this. The fuse portion 35 may have any shape as long as it has a smaller cross-sectional area than other portions.

As shown in FIGS. 16 to 19, the cross-sectional area of the fuse portion 35 may be reduced by providing notches on one side or both sides of the plate-like conductive pattern. The shape of the notch may be an arbitrary shape such as a triangle, a pentagon, a trapezoid, a rhombus, a parallelogram, a circle, and an ellipse, other than the rectangle. The number of notches is not limited to one, and a plurality of notches may be provided. In addition, the plurality of notches may be staggered or irregularly arranged at different positions in the length direction of the wiring.

In the example shown in FIG. 16, arcuate cutouts are formed on both sides of the fuse portion 35 . In the example shown in FIG. 17, a rectangular notch is formed on one side of the fuse portion 35 . In the example shown in FIG. 18, a triangular notch is formed on one side of the fuse portion 35 . In the example shown in FIG. 19, rectangular cutouts are formed on both sides of the fuse portion 35, and the cutouts on both sides are arranged alternately.

As described above, the power conversion device 300 according to the present embodiment includes the semiconductor element, the blocking mechanism 30, and the housing section 140. The semiconductor element is, for example, a field power semiconductor module 120, a stator power semiconductor module 121, or a power semiconductor switching element mounted thereon. The blocking mechanism 30 is electrically connected to the semiconductor element. The cutoff mechanism 30 is configured to cut off overcurrent. The housing part 140 is configured to accommodate the semiconductor element and the blocking mechanism 30 .

The blocking mechanism 30 is formed of a multilayer substrate 60 having a plurality of conductor layers and a plurality of insulating members. The plurality of conductor layers includes inner layers that are conductor layers formed inside the multilayer substrate 60 . The cutoff mechanism 30 has a fuse pattern 31 that melts when overcurrent flows. The fuse pattern 31 is formed in the inner layer of the multilayer substrate 60 among the plurality of conductor layers. The inside of the housing part 140 is filled with a potting material 150 . The potting material 150 is an example of the first resin member.

According to this configuration, since the fuse pattern 31 is formed in the inner layer of the multilayer substrate 60 , the periphery of the fuse pattern 31 is surrounded by the insulating member of the multilayer substrate 60 . Arc discharge may occur after the fuse pattern 31 is melted due to overcurrent. However, since the fuse pattern 31 is surrounded by the insulating member, the arc discharge is restricted to the space surrounded by the insulating member, and the cross-sectional area of the arc discharge does not increase. Also, when the insulating member of the multilayer substrate 60 is exposed to the arc discharge, a decomposition gas is generated from the insulating member. Therefore, the cross-sectional area of the arc discharge becomes smaller than the cross-sectional area of the space surrounded by the insulating member due to the ablation effect. As a result, the resistance value of the arc discharge, which is inversely proportional to the cross-sectional area of the arc discharge, increases and the arc discharge voltage increases. Therefore, the arc discharge current can be gradually reduced and the direct current can be interrupted. Therefore, according to the above configuration, overcurrent in the DC circuit can be cut off.

Further, according to the above configuration, since the fuse pattern 31 is provided in the inner layer of the multilayer substrate 60, it is possible to suppress the scattering of the melted material of the fuse pattern 31 and the like to other circuits.

High energy is generated inside the multilayer substrate 60 when the fuse pattern 31 is blown. For this reason, the fuse pattern 31 and the insulating member may peel off, and the space in which the fused portion of the fuse pattern 31 is provided may expand. In this case, the cross-sectional area of the arc discharge becomes large, and there is a concern that the arc discharge cannot be interrupted. However, according to the above configuration, since the multilayer substrate 60 can be pressed down by the potting material 150 and the housing portion 140, the peeling of the multilayer substrate 60 due to the energy generated when the fuse pattern 31 is blown is suppressed. be able to. Therefore, according to the above configuration, overcurrent in the DC circuit can be cut off more reliably.

Moreover, in the above configuration, the fuse pattern 31 is formed in the conductor layer of the multilayer substrate 60 . Therefore, the manufacturing cost of the power converter can be reduced as compared with a configuration in which a chip-type overcurrent cutoff fuse or a tube fuse is separately provided.

In power converter 300 according to the present embodiment, multilayer substrate 60 is a printed circuit board. According to this configuration, it is possible to connect the terminals using jet solder, so that the manufacturing man-hours can be reduced.

In power converter 300 according to the present embodiment, cutoff mechanism 30 has first terminal pattern 21 and second terminal pattern 22 . The first terminal pattern 21 is connected to one end of the fuse pattern 31 . The second terminal pattern 22 is connected to the other end of the fuse pattern 31 . A through hole 43 penetrating through the multilayer substrate 60 is formed in the second terminal pattern 22 . A pin terminal 187 is inserted into the through hole 43 . Through hole 43 is an example of a first through hole. Pin terminal 187 is an example of a terminal. According to this configuration, the pin terminals 187 have the effect of preventing peeling of the multilayer substrate 60, so that the arc discharge voltage can be increased and the current interrupting effect is improved. The first through hole may be formed in the first terminal pattern 21 .

In power converter 300 according to the present embodiment, cutoff mechanism 30 has first terminal pattern 21 and second terminal pattern 22 . The first terminal pattern 21 is connected to one end of the fuse pattern 31 . The second terminal pattern 22 is connected to the other end of the fuse pattern 31 . A through hole 16 penetrating through the multilayer substrate 60 is formed in the first terminal pattern 21 . The through holes 16 are filled with a potting material 150 . Through hole 16 is an example of a first through hole. The potting material 150 is an example of the first resin member. According to this configuration, the effect of preventing peeling of the multilayer substrate 60 by the potting material 150 can be obtained, so that the arc discharge voltage can be increased and the current interrupting effect is improved. The first through hole may be formed in the second terminal pattern 22 .

In power converter 300 according to the present embodiment, the voltage supplied to cutoff mechanism 30 is a DC voltage of 20 V or higher. According to this configuration, arc discharge is more likely to occur after the fuse pattern 31 is fused, so the effect of interrupting the arc discharge is more likely to be obtained.

In power converter 300 according to the present embodiment, potting material 150 is filled so as to cover field power semiconductor module 120 . The field power semiconductor module 120 is an example of a semiconductor element. With this configuration, the thickness of the potting material 150 covering the blocking mechanism 30 can be increased, so that the effect of preventing peeling of the multilayer substrate 60 is improved.

Power converter 300 according to the present embodiment further includes shield 199 . A shield 199 is arranged to cover the blocking mechanism 30 . The stiffness of the shield 199 is higher than the stiffness of the potting material 150 . According to this configuration, the effect of preventing peeling of the multilayer substrate 60 is improved. Furthermore, electromagnetic noise from the fuse pattern 31 can be shielded by the shield 199, and heat generated in the fuse pattern 31 can be efficiently radiated through the shield 199. FIG.

A rotating electrical machine 1000 according to the present embodiment includes a power conversion device 300 according to the present embodiment and a rotating electrical machine body 200 . The rotary electric machine body 200 includes a rotor shaft 4, a rotor 6 that rotates integrally with the rotor shaft 4, a stator 3 arranged radially outside the rotor 6, and the rotor 6 and the stator 3. has a housing 10 covering the outside of the According to this configuration, in rotating electric machine 1000, the same effects as described above can be obtained.

Embodiment 2.
A power converter according to Embodiment 2 will be described. 20 to 25 are plan views showing the configuration of the cutoff mechanism of the power converter according to this embodiment. FIGS. 20 to 25 show the structures of the first to sixth layers of the multilayer substrate 60, respectively. 26 is a sectional view showing the XXVI-XXVI section of FIG. 20. FIG. Components having the same functions and actions as those of the first embodiment are given the same reference numerals, and descriptions thereof are omitted.

A power conversion device 300 according to the present embodiment differs from that of the first embodiment in that it has a scattering prevention pattern for preventing scattering of blown material of a fuse pattern 31 . The scattering prevention pattern is formed by one of the plurality of conductive patterns that the multilayer substrate 60 has. The scattering prevention pattern is formed in a layer different from the layer in which the fuse pattern 31 is formed, among the first to sixth layers of the multilayer substrate 60 . When viewed in the direction normal to the substrate surface of the multilayer substrate 60, the anti-scattering pattern overlaps at least a portion of the blown portion of the fuse pattern 31, ie, at least a portion of the fuse portion 35. As shown in FIG.

In this embodiment, a plurality of anti-scattering patterns are formed. The first anti-scattering pattern 40a and the second anti-scattering pattern 40b are formed in different layers.

The first scattering prevention pattern 40a is formed on the first layer. That is, the first scattering prevention pattern 40a is formed in a layer on the rear side of the layer in which the fuse pattern 31 is formed. In the first layer, the first scattering prevention pattern 40 a is connected to the second terminal pattern 22 and separated from the first terminal pattern 21 .

The second scattering prevention pattern 40b is formed on the sixth layer. That is, the second anti-scatter pattern 40b is formed in a layer closer to the front side than the layer in which the fuse pattern 31 is formed. In the sixth layer, the second scattering prevention pattern 40b is connected to the first terminal pattern 21 and separated from the second terminal pattern 22. As shown in FIG.

The first terminal pattern 21 and the second terminal pattern 22 are electrically connected only through the fuse pattern 31 . Therefore, no current flows through the first anti-scattering pattern 40a and the second anti-scattering pattern 40b.

Both the first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b are formed in a rectangular plate shape covering the entire fuse portion 35 . The first scattering prevention pattern 40 a overlaps at least a portion of the fuse portion 35 when viewed in the normal direction of the substrate surface of the multilayer substrate 60 . When viewed in the same direction, the second scattering prevention pattern 40b overlaps at least a portion of the fuse portion 35. As shown in FIG.

The first anti-scattering pattern 40a and the second anti-scattering pattern 40b are made of copper foil, for example. The first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b are made of the same material as the fuse pattern 31 .

In the present embodiment, the first scattering prevention pattern 40a and the second scattering prevention pattern 40b are provided in a layer different from the layer in which the fuse pattern 31 is provided. The first anti-scattering pattern 40 a and the second anti-scattering pattern 40 b have Young's modulus higher than the Young's modulus of the base material 19 . Both the first anti-scattering pattern 40a and the second anti-scattering pattern 40b overlap the blown portion of the fuse pattern 31, that is, the fuse portion 35 when viewed in the normal direction of the substrate surface.

Therefore, when the fuse pattern 31 is blown, the first anti-scattering pattern 40a and the second anti-scattering pattern 40b can prevent the melted material of the fuse pattern 31 from scattering to other circuits. Furthermore, by providing the first anti-scattering pattern 40a and the second anti-scattering pattern 40b having a Young's modulus higher than that of the base material 19, the effect of preventing peeling of the multilayer substrate 60 is more exhibited, and the effect of interrupting the arc discharge is improved. .

Also, the first anti-scattering pattern 40 a and the second anti-scattering pattern 40 b have thermal conductivity higher than that of the substrate 19 . As a result, the heat generated by the fuse pattern 31 during normal operation of the power converter 300 can be dissipated to the first anti-scatter pattern 40a and the second anti-scatter pattern 40b, so that the temperature rise of the fuse pattern 31 can be reduced. Furthermore, noise radiated from the fuse pattern 31 can be suppressed by providing the first anti-scattering pattern 40a and the second anti-scattering pattern 40b.

<Modification 2-1>
27 to 32 are plan views showing the configuration of the cutoff mechanism of the power converter according to modification 2-1 of the present embodiment. 27 to 32 show the structures of the first to sixth layers of the multilayer board 60, respectively. 33 is a sectional view showing the XXXIII-XXXIII section of FIG. 27. FIG.

In the configuration shown in FIGS. 20 to 26, the first anti-scatter pattern 40a and the second anti-scatter pattern 40b are formed on the outer layers of the multilayer substrate 60, respectively. Each of the patterns 40b may be formed in an inner layer of the multilayer substrate 60. FIG.

As shown in FIGS. 27 to 33, the first anti-scatter pattern 40a is formed on the second layer, which is the inner layer of the multilayer substrate 60. As shown in FIGS. The second scattering prevention pattern 40 b is formed on the fourth layer, which is the inner layer of the multilayer substrate 60 . Both the first scattering prevention pattern 40a and the second scattering prevention pattern 40b are formed in a layer adjacent to the third layer in which the fuse pattern 31 is formed.

By forming the first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b in the inner layer of the multilayer substrate 60 , each of the first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b and the fuse pattern 31 . The thickness of the substrate 19 can be reduced. Therefore, it is possible to further prevent the melted material of the fuse pattern 31 from scattering to other circuits. In addition, the effect of preventing peeling of the multilayer substrate 60 is more exhibited, and the effect of interrupting arc discharge is improved. Furthermore, it is possible to reduce the temperature rise of the fuse pattern 31 when the power conversion device 300 normally operates.

In this way, the first anti-scatter pattern 40a and the second anti-scatter pattern 40b can be arranged on either the outer layer or the inner layer as long as the layer is different from the fuse pattern 31 .

<Modification 2-2>
34 to 39 are plan views showing the configuration of the cutoff mechanism of the power converter according to modification 2-2 of the present embodiment. 34 to 39 show the structures of the first to sixth layers of the multilayer board 60, respectively.

As shown in FIGS. 34 to 39, the first anti-scatter pattern 40a is separated from both the first terminal pattern 21 and the second terminal pattern 22. As shown in FIGS. Therefore, the first scattering prevention pattern 40 a has a potential different from that of the fuse pattern 31 . Similarly, the second scattering prevention pattern 40 b is separated from both the first terminal pattern 21 and the second terminal pattern 22 . Therefore, the second anti-scatter pattern 40b has a potential different from that of the fuse pattern 31 .

After the fuse pattern 31 is fused, the remaining portion of the fuse pattern 31 may be electrically connected to the first anti-scattering pattern 40a or the second anti-scattering pattern 40b by the melted material of the fuse pattern 31. be. In this modification, since the first anti-scattering pattern 40a and the second anti-scattering pattern 40b are separated from both the first terminal pattern 21 and the second terminal pattern 22, even in the above case, short-circuiting is prevented even in the above case. It is possible to prevent the current from continuing to flow.

<Modification 2-3>
40 to 45 are plan views showing the configuration of the cutoff mechanism of the power converter according to modification 2-3 of the present embodiment. 40 to 45 show the structures of the first to sixth layers of the multilayer substrate 60, respectively.

As shown in FIGS. 40 to 45, the first anti-scatter pattern 40a is separated from both the first terminal pattern 21 and the second terminal pattern 22. As shown in FIGS. Therefore, the first scattering prevention pattern 40 a has a potential different from that of the fuse pattern 31 . Similarly, the second scattering prevention pattern 40 b is separated from both the first terminal pattern 21 and the second terminal pattern 22 . Therefore, the second anti-scatter pattern 40b has a potential different from that of the fuse pattern 31 .

In this modification, a first connecting pattern 44a and a second connecting pattern 44b are provided in each of the first to sixth layers. The first connection pattern 44a and the second connection pattern 44b are made of copper foil and have electrical conductivity. The first connection pattern 44 a and the second connection pattern 44 b are made of the same material as the first terminal pattern 21 and the second terminal pattern 22 . The first connection pattern 44a and the second connection pattern 44b have a rectangular plate shape in this example.

The first connection patterns 44a of each layer are arranged at positions overlapping each other when viewed in the normal direction of the substrate surface. In each layer, the first connecting pattern 44 a is separated from both the first terminal pattern 21 and the second terminal pattern 22 . A cylindrical through hole 45a is provided in the first connection pattern 44a. The through-holes 45 a pass through the multilayer substrate 60 and are open on one substrate surface and the other substrate surface of the multilayer substrate 60 . A plurality of through holes 45a may be formed. The first connecting patterns 44a of each layer are electrically connected via through holes 45a.

The second connection patterns 44b of each layer are arranged at positions overlapping each other when viewed in the normal direction of the substrate surface. The second connecting pattern 44b is separated from both the first terminal pattern 21 and the second terminal pattern 22 in each layer. A cylindrical through hole 45b is provided in the second connection pattern 44b. The through holes 45 b pass through the multilayer substrate 60 and open on one substrate surface and the other substrate surface of the multilayer substrate 60 . A plurality of through holes 45b may be formed. The second connection patterns 44b of each layer are electrically connected via through holes 45b.

Although the first connection pattern 44a and the second connection pattern 44b are provided in this modification, only one of the first connection pattern 44a and the second connection pattern 44b may be provided.

In a plane parallel to the substrate surface of the multilayer substrate 60, the extending direction of the fuse pattern 31 is defined as the Y direction, and the direction perpendicular to the Y direction is defined as the X direction. 40 to 45, the horizontal direction is the Y direction, and the vertical direction is the X direction. At this time, both the first connection pattern 44a and the second connection pattern 44b are arranged on one side of the fuse pattern 31 in the X direction.

The first connection pattern 44a is arranged closer to one side in the Y direction than the central portion of the fuse pattern 31 in the Y direction when viewed in the normal direction of the substrate surface. The second connection pattern 44b is arranged closer to the other side in the Y direction than the central portion of the fuse pattern 31 in the Y direction when viewed in the normal direction of the substrate surface. The fuse portion 35, which is a blown portion, is provided in the central portion of the fuse pattern 31 in the Y direction.

In each layer, the first connecting pattern 44a is arranged on one side of the first terminal pattern 21 in the X direction with a space therebetween. In each layer, the second connection pattern 44b is arranged on one side of the second terminal pattern 22 in the X direction with a space therebetween.

The first scattering prevention pattern 40a is electrically and thermally connected to the first connection pattern 44a and the second connection pattern 44b provided in the same layer. Similarly, the second scattering prevention pattern 40b is electrically and thermally connected to the first connection pattern 44a and the second connection pattern 44b provided in the same layer. As a result, the first anti-scattering pattern 40a and the second anti-scattering pattern 40b can be made to have the same potential, thereby improving the noise shielding effect.

Further, for example, the first connection pattern 44a or the second connection pattern 44b of the sixth layer and a convex portion (not shown) formed on the housing portion 140 may be electrically connected. In this case, the potentials of the first anti-scattering pattern 40a and the second anti-scattering pattern 40b can be set to the same potential as the casing 140, that is, the ground potential. Therefore, the noise shielding effect is further improved. Further, when the first connection pattern 44a or the second connection pattern 44b of the sixth layer and the convex portion (not shown) formed on the housing portion 140 are thermally connected, the power conversion device The heat generation of the fuse pattern 31 during normal operation of the device 300 is controlled by the base material 19, the first scattering prevention pattern 40a, the second scattering prevention pattern 40b, the through holes 45a, the through holes 45b, the first connection pattern 44a, and the second connection pattern. Heat can be dissipated to the housing 140 via 44b. Therefore, the temperature rise of the fuse pattern 31 can be reduced.

The first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b may have the same thickness as the fuse pattern 31 or may have a different thickness from the fuse pattern 31 . For example, when the thickness of the first anti-scattering pattern 40a and the second anti-scattering pattern 40b is greater than the thickness of the fuse pattern 31, the rigidity of the first anti-scattering pattern 40a and the second anti-scattering pattern 40b is improved. The effect of preventing peeling of the multilayer substrate 60 is improved. Furthermore, the heat generated by the fuse pattern 31 during normal operation can be easily dissipated to the first anti-scattering pattern 40a and the second anti-scattering pattern 40b, so that the temperature rise of the fuse pattern 31 can be reduced.

As described above, in the power conversion device 300 according to the present embodiment, the cutoff mechanism 30 has the first anti-scattering pattern 40a and the second anti-scattering pattern 40b that prevent the blown material of the fuse pattern 31 from scattering. ing. Each of the first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b is formed on a conductor layer different from the fuse pattern 31 among the plurality of conductor layers of the multilayer substrate 60 . Each of the first anti-scattering pattern 40 a and the second anti-scattering pattern 40 b overlaps at least a portion of the blown portion of the fuse pattern 31 when viewed in the direction normal to the substrate surface of the multilayer substrate 60 . According to this configuration, it is possible to prevent the melted material of the fuse pattern 31 from scattering to other circuits.

In power conversion device 300 according to the present embodiment, the plurality of conductor layers of multilayer substrate 60 are different from the inner layer in which fuse pattern 31 is formed as a conductor layer formed inside multilayer substrate 60. have. The first anti-scattering pattern 40 a and the second anti-scattering pattern 40 b are each formed in the separate inner layer of the multilayer substrate 60 . According to this configuration, since the thickness of the insulating member between each of the first anti-scattering pattern 40a and the second anti-scattering pattern 40b and the fuse pattern 31 can be reduced, the fused material of the fuse pattern 31 can be reduced. scattering to other circuits can be further suppressed.

In the power conversion device 300 according to the present embodiment, each of the first anti-scattering pattern 40a and the second anti-scattering pattern 40b has a ground potential. This configuration improves the noise shielding effect of the fuse pattern 31 by the first anti-scattering pattern 40a and the second anti-scattering pattern 40b.

Embodiment 3.
A power converter according to Embodiment 3 will be described. FIG. 46 is a cross-sectional view showing the configuration of the cutoff mechanism of the power converter according to this embodiment. Components having the same functions and actions as those in the first or second embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.

Power conversion device 300 according to the present embodiment differs from Embodiment 1 in that resin member 80 is provided between multilayer substrate 60 in which cutoff mechanism 30 is formed and housing portion 140. different. As shown in FIG. 46 , resin member 80 is formed between blocking mechanism 30 and housing 140 . The resin member 80 is arranged so as to overlap the fuse pattern 31 when viewed in the direction normal to the substrate surface of the multilayer substrate 60 .

The resin member 80 has a Young's modulus lower than both the Young's modulus of the side wall 131 of the housing part 140 and the Young's modulus of the potting material 150 . For example, the Young's modulus of the resin member 80 is on the order of several tens of MPa, such as 10 MPa to 30 MPa. For example, the resin member 80 is made of rubber material, silicone rubber, silicone gel, or the like.

In this embodiment, since the resin member 80 having a strength lower than that of the side wall 131 and the potting material 150 is provided, when the fuse pattern 31 is fused, the melted material scattered through the base material 19 is Absorbed at 80. Therefore, it is possible to prevent the melted material from scattering around, and to reliably maintain interruption of the short-circuit current.

The resin member 80 may be made of a resin material that extinguishes arc discharge that occurs when the fuse pattern 31 melts. In general, arcing occurs when the power supply voltage is 20V or higher. In the power conversion device 300, if the voltage of the battery 500 is 20 V or higher, an arc may occur after the fuse pattern 31 is blown. Since the resin member 80 is made of a resin material that extinguishes the arc discharge, it is possible to suppress the continuation of the short-circuit current due to the arc discharge, and the fuse pattern 31 can be blown out immediately. Current can be interrupted.

The resin member 80 may have thermal conductivity higher than that of the potting material 150 . Also, the resin member 80 may be thermally connected to the multilayer substrate 60 and the housing section 140 . In this case, the heat generated by the fuse pattern 31 during normal operation of the power converter 300 can be dissipated to the housing 140 through the resin member 80, and the temperature rise of the fuse pattern 31 can be reduced.

<Modification 3-1>
FIG. 47 is a cross-sectional view showing the configuration of the cutoff mechanism of the power converter according to Modification 3-1 of the present embodiment. As shown in FIG. 47, the housing part 140 may have a convex part 140a. The resin member 80 is provided between the blocking mechanism 30 formed on the multilayer substrate 60 and the housing portion 140 . Since the thickness of the resin member 80 is reduced by the protrusions 140a, the heat resistance of the resin member 80 is reduced. Therefore, it is possible to further reduce the temperature rise of the fuse pattern 31 when the power conversion device 300 normally operates.

As described above, in power conversion device 300 according to the present embodiment, resin member 80 is provided between blocking mechanism 30 and housing portion 140 . The resin member 80 is an example of a second resin member. The resin member 80 has a Young's modulus lower than that of the potting material 150 . According to this configuration, when the fuse pattern 31 is fused, the fuse scattered through the insulating member of the multilayer substrate 60 is absorbed by the resin member 80 . Therefore, it is possible to prevent the melted material from scattering around, and to reliably maintain interruption of the short-circuit current.

Embodiment 4.
A power converter according to Embodiment 4 will be described. 48 to 53 are plan views showing the configuration of the cutoff mechanism of the power converter according to this embodiment. FIGS. 48 to 53 show the structures of the first to sixth layers of the multilayer board 60, respectively. Components having the same functions and actions as those in any one of the first to third embodiments are denoted by the same reference numerals, and descriptions thereof are omitted.

A power conversion device 300 according to the present embodiment differs from that of the first embodiment in that through holes 17 are provided.

As shown in FIGS. 48 to 53, through holes 17 are formed in the multilayer substrate 60 in addition to the through holes 16 and 43. As shown in FIGS. The through hole 17 is formed around the fuse pattern 31 when viewed in the direction normal to the substrate surface. In this embodiment, four through holes 17 are arranged two by two on both sides of the fuse pattern 31 when viewed in the direction normal to the substrate surface. Each of the through holes 17 penetrates the multilayer substrate 60 .

A land 23 is formed around each through-hole 17 in each of the first to sixth layers. Land 23 is made of the same material as fuse pattern 31 . In each layer, the land 23 is separated from the first terminal pattern 21 and the second terminal pattern 22 . The land 23 of the third layer is separated from the fuse pattern 31 .

A plated layer (not shown) is formed on the inner wall of the through hole 17 . The lands 23 of each layer may be electrically connected through the through holes 17 . Lands 23 and through holes 17 have different potentials than fuse patterns 31 .

In the present embodiment, through holes 17 are formed, so that the strength of multilayer substrate 60 in the thickness direction is improved. Therefore, the effect of preventing peeling of the multilayer substrate 60 is improved, and the current interrupting performance after the fuse pattern 31 is melted is improved.

The interior of the through hole 17 may be a space, or the interior of the through hole 17 may be filled with a potting material 150 . When the inside of the through-hole 17 is filled with the potting material 150, the effect of preventing the peeling of the multilayer substrate 60 is further improved.

<Modification 4-1>
54 to 59 are plan views showing the configuration of the cutoff mechanism of the power converter according to Modification 4-1 of the present embodiment. FIGS. 54 to 59 show the structures of the first to sixth layers of the multilayer board 60, respectively.

As shown in FIGS. 54 to 59, the through holes 17 may be connected to the first anti-scattering pattern 40a and the second anti-scattering pattern 40b. In the second layer, the through holes 17 are formed in the first scattering prevention pattern 40a. In the fourth layer, the through holes 17 are formed in the second scattering prevention pattern 40b. As a result, the first anti-scattering pattern 40a of the second layer, the second anti-scattering pattern 40b of the fourth layer, and the lands 23 of the first, third, fifth, and sixth layers are formed into through holes. 17 are electrically connected.

This further improves the strength of the multilayer substrate 60 in the thickness direction, thereby further improving the effect of preventing the peeling of the multilayer substrate 60 .

As described above, in power conversion device 300 according to the present embodiment, through holes 17 penetrating multilayer substrate 60 are formed around fuse pattern 31 . Through hole 17 is an example of a second through hole. According to this configuration, the effect of preventing peeling of the multilayer substrate 60 is improved by the through holes 17 .

In the power conversion device 300 according to the present embodiment, the cutoff mechanism 30 has a first anti-scattering pattern 40a and a second anti-scattering pattern 40b that prevent the melted material of the fuse pattern 31 from scattering. Each of the first anti-scatter pattern 40 a and the second anti-scatter pattern 40 b is formed on a conductor layer different from the fuse pattern 31 among the plurality of conductor layers of the multilayer substrate 60 . Each of the first anti-scattering pattern 40 a and the second anti-scattering pattern 40 b overlaps at least a portion of the blown portion of the fuse pattern 31 when viewed in the direction normal to the substrate surface of the multilayer substrate 60 . The through hole 17 is connected to the first anti-scattering pattern 40a and the second anti-scattering pattern 40b. According to this configuration, the strength in the thickness direction of the multilayer substrate 60 is improved, so the effect of preventing the peeling of the multilayer substrate 60 is improved.

In power converter 300 according to the present embodiment, through holes 17 are filled with potting material 150 . According to this configuration, the strength in the thickness direction of the multilayer substrate 60 is improved, so the effect of preventing the peeling of the multilayer substrate 60 is improved.

The above embodiments and modifications can be implemented in combination with each other.

1 front bracket 2 rear bracket 3 stator 3a stator core 3b stator winding 4 rotor shaft 5 field winding 6 rotor 9 pulley 10 housing 11a first intake port 11b second intake port 12a first exhaust port 12b second exhaust port 16 through hole 17 through hole 19 substrate 21 first terminal pattern 22 second terminal pattern 23 land 30 blocking mechanism 31 Fuse pattern 33 First terminal side base 34 Second terminal side base 35 Fuse part 40a First scattering prevention pattern 40b Second scattering prevention pattern 43 Through hole 44a First connection pattern 44b Second connection pattern , 45a through hole, 45b through hole, 51 solder, 52 solder, 60 multilayer substrate, 71 front side bearing, 72 rear side bearing, 73 first cooling fan, 74 second cooling fan, 80 resin member, 100 brush, 110 rotation Sensor, 120 field power semiconductor module, 121 stator power semiconductor module, 121U U-phase power semiconductor module, 121V V-phase power semiconductor module, 121W W-phase power semiconductor module, 122 smoothing capacitor, 123 filter core, 124 control board , 125 positive electrode side conductor, 126 filter capacitor, 127 filter coil, 130 cover, 131 side wall, 132 bottom wall, 132a support, 140 housing, 140a projection, 141 fin, 143 projection, 150 potting material, 153 wiring member , 171 upper arm power semiconductor switching element, 172 lower arm power semiconductor switching element, 173 positive terminal, 174 negative terminal, 175 AC terminal, 176 signal terminal, 177 heat dissipation surface, 178 third screw, 179 first screw, 183 Positive side terminal 184 Negative side terminal 185 Positive side terminal 186 Negative side terminal 187 Pin terminal 188 Terminal 190 Positive side terminal 191 Negative side terminal 192 Positive side terminal 193 Partial portion 194 Negative side terminal 195 Positive side Terminal 196 Negative terminal 197 Fourth screw 198 Fifth screw 199 Shield 200 Rotating electric machine body 211 Connection bus bar 300 Power converter 500 Battery 501 Positive terminal 502 Negative terminal 503 Positive side cable, 504 negative electrode side cable, 1000 rotating electric machine.

Claims (16)

a semiconductor element;
a blocking mechanism that is electrically connected to the semiconductor element and blocks overcurrent;
a housing portion that houses the semiconductor element and the blocking mechanism;
with
The blocking mechanism is formed of a multilayer substrate having a plurality of conductor layers and a plurality of insulating members,
The plurality of conductor layers includes an inner layer that is a conductor layer formed inside the multilayer substrate,
The breaking mechanism has a fuse pattern that melts when the overcurrent flows,
The fuse pattern is formed in the inner layer,
A power conversion device in which the inside of the casing is filled with a first resin member. 2. The power converter according to claim 1, wherein said multilayer board is a printed board. The blocking mechanism has a first terminal pattern connected to one end of the fuse pattern and a second terminal pattern connected to the other end of the fuse pattern,
a first through hole penetrating the multilayer substrate is formed in the first terminal pattern or the second terminal pattern,
3. The power converter according to claim 1, wherein a terminal is inserted into said first through hole. The blocking mechanism has a first terminal pattern connected to one end of the fuse pattern and a second terminal pattern connected to the other end of the fuse pattern,
a first through hole penetrating the multilayer substrate is formed in the first terminal pattern or the second terminal pattern,
3. The power converter according to claim 1, wherein said first through hole is filled with said first resin member. The blocking mechanism has a scattering prevention pattern that prevents scattering of the melted material of the fuse pattern,
the scattering prevention pattern is formed on a conductor layer different from the fuse pattern among the plurality of conductor layers,
The anti-scattering pattern according to any one of claims 1 to 4, wherein the anti-scattering pattern overlaps at least a part of the blown portion of the fuse pattern when viewed in the direction normal to the substrate surface of the multilayer substrate. Power converter. The plurality of conductor layers includes another inner layer different from the inner layer as a conductor layer formed inside the multilayer substrate,
6. The power converter according to claim 5, wherein said anti-scattering pattern is formed on said another inner layer. 7. The power converter according to claim 5, wherein said anti-scattering pattern has a ground potential. The power converter according to any one of claims 1 to 7, wherein the voltage supplied to the cutoff mechanism is a DC voltage of 20V or more. The power converter according to any one of claims 1 to 8, wherein a second resin member is provided between the blocking mechanism and the housing. The power converter according to claim 9, wherein said second resin member has a Young's modulus lower than that of said first resin member. The power conversion device according to any one of claims 1 to 10, wherein a second through hole penetrating through the multilayer substrate is formed around the fuse pattern. The blocking mechanism has a scattering prevention pattern that prevents scattering of the melted material of the fuse pattern,
the scattering prevention pattern is formed on a conductor layer different from the fuse pattern among the plurality of conductor layers,
The anti-scattering pattern overlaps at least a part of the blown portion of the fuse pattern when viewed in the direction normal to the substrate surface of the multilayer substrate,
12. The power converter according to claim 11, wherein said second through hole is connected to said anti-scattering pattern. The power converter according to claim 11 or 12, wherein the second through hole is filled with the first resin member. The power converter according to any one of claims 1 to 13, wherein the first resin member is filled so as to cover the semiconductor element. Further comprising a shield arranged to cover the blocking mechanism,
The power converter according to any one of claims 1 to 14, wherein the rigidity of the shield is higher than the rigidity of the first resin member. A power conversion device according to any one of claims 1 to 15,
A rotor having a rotor shaft, a rotor that rotates integrally with the rotor shaft, a stator arranged radially outside the rotor, and a housing that covers the rotor and the stator. an electric machine body;
Rotating electric machine with

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