JP2009254106A - Instantaneous voltage drop compensator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an instantaneous voltage drop compensator in which the heat sink is effectively utilized, the reduction in size and weight is achieved, and assembly into the other equipment is easy. <P>SOLUTION: In the instantaneous voltage drop compensator, electric power of a commercial power supply is supplied to a load during normal operation, and the electric power is supplied to the load by a voltage generated from a charging voltage of a compensation capacitor at the time of instantaneous voltage drop. This compensator includes: power semiconductor elements Q<SB>1</SB>, Q<SB>3</SB>; a metal plate 13 which is commonly provided for the power semiconductor elements Q<SB>1</SB>, Q<SB>3</SB>and in which the power semiconductor elements Q<SB>1</SB>, Q<SB>3</SB>are mounted on one main surface 13a side; heat spreaders HS<SB>1</SB>, HS<SB>3</SB>which are separatedly provided at the power semiconductor elements Q<SB>1</SB>, Q<SB>3</SB>respectively and are joined to respective power semiconductor elements; an insulating layer 14 interposed between the respective heat spreaders HS<SB>1</SB>, HS<SB>3</SB>and the metal plate 13; and a heat sink H which abuts on the other main surface 13b side of the metal plate 13. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  In the present invention, when an instantaneous voltage drop occurs in a commercial power source that supplies power to a load, the commercial power source and the load are disconnected, and instantaneous power is supplied to the load by a compensation voltage generation circuit provided in parallel to the commercial power source. The present invention relates to a voltage drop compensation device.

  In recent years, due to the widespread use of various electronic devices such as power electronics equipment and computers, not only power outages due to lightning strikes, but also instantaneous voltage drops for about 0.2 to 1 second that do not lead to power outages (hereinafter simply referred to as “instantaneous drops”) The failure of various electrical equipment due to is a problem. For this reason, in critical load facilities such as bank online facilities and traffic control facilities, an instantaneous voltage drop compensator is introduced that quickly detects the instantaneous drop that occurs in commercial AC power and compensates the power to be supplied to the critical load facility. (For example, refer to Patent Document 1).

  FIG. 1 shows a constant commercial power supply type instantaneous voltage drop compensator that has been conventionally used. The instantaneous voltage drop compensation device 1 ′ mainly includes a system changeover switch circuit 2 and a compensation voltage generation circuit 3. Among these, the system changeover switch circuit 2 connects the commercial power source 4 and the load 5 to constantly supply the power of the commercial power source 4 to the load 5, and disconnects the commercial power source 4 and the load 5 when an instantaneous drop occurs. The power supply from is cut off. In addition, the compensation voltage generation circuit 3 supplies the power stored in the compensation capacitor C to the load when the instantaneous drop occurs.

Specifically, the system changeover switch circuit 2 includes a bridge diode composed of diodes D _{6 to} D ₉ and power semiconductor elements Q ₅ and Q ₆ such as IGBT (insulated gate bipolar transistor). Further, a resistor R ₂ for limiting an inrush current generated when the load 5 is connected is provided on the side of the commercial power supply 4 of the power semiconductor element Q ₆ . In this configuration, when both the power semiconductor elements Q ₅ and Q ₆ are turned off, the commercial power supply 4 and the load 5 are disconnected.
Compensation voltage generating circuit 3 is mainly the compensation capacitor C, a coil L, a booster circuit consisting of power semiconductor elements _{Q 8} and diode _{D 5,} the power semiconductor element _Q 1 to Q ₄ and a reflux diode _D 1 to D ₄ The inverter which consists of. When an instantaneous drop occurs in the commercial power supply 4, the charging voltage of the compensation capacitor C is boosted by the booster circuit to generate a predetermined DC voltage, and the DC voltage is switched by the inverter and output to the load 5. A voltage is generated. As a result, the required power is supplied to the load 5 even during a momentary drop, and the instantaneous voltage drop is compensated.
Note that the gate of each power semiconductor element is appropriately controlled by a control unit (not shown).

Usually during operation sag is not generated, by connecting this instantaneous voltage drop compensating device 1 'to a commercial power source 4, a load 5 is the commercial power source 4, the resistance from the viewpoint of limiting the inrush current R ₂ and the power semiconductor device Q ₆ is connected. Thereafter, the power semiconductor element Q ₆ is ON the power semiconductor device Q ₅ together are turned OFF, the load and the commercial power supply 4 5 are connected via the power semiconductor element Q _5. Therefore, the power loss is not generated in the resistor R ₂ at the time of normal operation. When the commercial power supply 4 and the load 5 are connected, charging of the compensation capacitor C is started. Charging is performed via the freewheeling diodes D _{1 to} D ₄ , the power semiconductor element Q ₇ , and the resistor R ₁ . The compensation capacitor C is charged to a predetermined voltage, the power semiconductor element Q ₇ is OFF. Thereafter, the power semiconductor element Q _7, the charging voltage of the compensation capacitor C is ON only when lowered by leakage current, the charging voltage is kept constant.

On the other hand, when the instantaneous drop occurs, it is OFF the power semiconductor device Q ₅ immediately, a load 5 is the commercial power source 4 is disconnected. At the same time, boosting of the charging voltage of the compensation capacitor C is started, and the DC voltage obtained by boosting is switched by the inverter, and the AC voltage is output to the load 5.
When the commercial power source 4 returns from the voltage sag condition, is connected the load 5 and the commercial power source 4 is turned ON the power semiconductor device Q _5, the step-up and switching in the compensation voltage generating circuit 3 is stopped.

As shown in FIG. 7, as the power semiconductor element provided in the instantaneous voltage drop compensator 1 ′, a discrete component that is easy to handle is usually used.
Here, in order to operate the power semiconductor element Q safely, it is necessary to efficiently dissipate heat so that the operating temperature does not exceed the junction temperature. For this reason, the power semiconductor element Q is usually provided with a heat sink H with a thermal compound in between, and the fin portion is ventilated by a fan and cooled. On the other hand, an instantaneous voltage drop compensator with a relatively small power scale of several hundred VA to several kVA may be designed so that it can sufficiently dissipate natural heat without using a fan from the viewpoint of installation location and cost. In this case, a relatively large heat sink is required.

  The power semiconductor element Q has an active electrode A having the same potential as the collector, and the active electrode A is in contact with the heat sink H. Therefore, a plurality of power semiconductor elements Q having different collector potentials cannot be directly attached to one heat sink H for cooling.

From the above, the conventional instantaneous voltage drop compensator 1 ′ is generally configured as shown in FIG. That is, the power semiconductor device Q ₅ strains switching circuit 2 is provided on the back surface side of the substrate 6, is radiated in large heat sink H _5. The power semiconductor elements Q _{1 to} Q ₄ constituting the inverter are provided on the surface side of the substrate 6 and radiated by the heat sinks H _{1 to} H ₄ , respectively. Further, the substrate 6 is attached to the heat sink H ₅ via a spacer 7 provided at the four corners, thereby a space for arranging the power semiconductor device Q ₅ is ensured.
In FIG. 8, only the power semiconductor elements Q _{1 to} Q ₅ that generate a relatively large amount of heat are displayed, and the other power semiconductor elements and the compensation capacitor C shown in FIG. 1 are omitted.
JP 2008-54468 A

  However, the conventional instantaneous voltage drop compensator 1 ′ has the following two problems.

[First problem]
As described above, the instantaneous voltage drop compensator 1 ′ shown in FIG. 1 includes the plurality of power semiconductor elements Q _{1 to} Q ₈ , but not all of them are used at the same time. For example, only one of the power semiconductor elements Q ₅ and Q ₆ in the system changeover switch circuit 2 is turned on during normal operation, and the commercial power supply 4 and the load 5 are connected. Further, while the power semiconductor elements Q ₅ and Q _{6 of} the system changeover switch circuit 2 are turned on during normal operation, the power semiconductor elements Q _{1 to} Q ₄ of the compensation voltage generation circuit 3 are turned on only at the time of a momentary drop.

Accordingly, during normal operation, only the heat sink H ₅ for cooling the power semiconductor element Q ₅ functions and the heat sinks H _{1 to} H ₄ provided in the power semiconductor elements Q _{1 to} Q ₄ that do not generate heat (is not driven) radiate heat. Hardly contributes. On the contrary, at the time of a sag, the heat sinks H _{1 to} H ₄ radiate the power semiconductor elements Q _{1 to} Q ₄ , and the heat sink H ₅ provided in the power semiconductor element Q ₅ that does not generate heat hardly contributes to the heat dissipation. .

  That is, the conventional instantaneous voltage drop compensator 1 ′ shown in FIG. 8 includes a heat sink for each power semiconductor element, but all the heat sinks do not contribute to heat dissipation at the same time, and the heat sink can be used effectively. There was no situation.

[Second problem]
Further, in the conventional instantaneous voltage drop compensating device 1 'shown in FIG. 8, as described above, it is necessary to provide a space between the substrate 6 and the heatsink H _5. Further, when the instantaneous voltage drop compensator 1 ′ is incorporated in another device, the heat sink H ₅ also serves as an outer case of the device, but when the heat sink H ₅ is a part of the outer case. , heat sink H ₅ had been large in size to more than necessary. All of these have led to an increase in the size of the instantaneous voltage drop compensator 1 ', which has been an obstacle to the use by incorporating it into other devices.

  Accordingly, an object of the present invention is to provide an instantaneous voltage drop compensation device that can effectively use a heat sink, can be reduced in size and weight, and can be easily incorporated into other devices.

  In order to solve the above problems, an instantaneous voltage drop compensator according to the present invention has at least one first power semiconductor element, and connects a commercial power source and a load during normal operation to supply the power of the commercial power source to the power source. A system changeover switch circuit that supplies power to the load via a first power semiconductor element and interrupts power supply from the commercial power source to the load when an instantaneous voltage drops, a power storage unit that stores power, and a plurality of second powers A compensation voltage generating circuit that has a semiconductor element and generates a compensation voltage from the electric power stored in the power storage unit using the plurality of second power semiconductor elements when an instantaneous voltage drop occurs and supplies the compensation voltage to the load; In the instantaneous voltage drop compensator provided, the first and second power semiconductor elements are provided in common, and both the first and second power semiconductor elements are one of them. A metal plate mounted on the surface side; a plurality of heat spreaders provided separately from each other for each of the first and second power semiconductor elements; and joined to each power semiconductor element; and each of the heat spreaders and the metal plate And an insulating layer interposed therebetween, and a heat sink provided in contact with the other main surface of the metal plate.

According to this configuration, the first power semiconductor element is driven only during normal operation, while the second power semiconductor element is driven only during a sag. That is, the first power semiconductor element and the second power semiconductor element are not driven simultaneously. For this reason, during normal operation, it is only necessary to consider steady heat generation without considering transient heat generation at the time of a sag, and it is possible to effectively use the heat sink by dissipating heat with a single heat sink. It has become.
Here, in the case where there are power semiconductor elements that output different potentials from among the first and second power semiconductor elements, in order to avoid mutual conduction between these power semiconductor elements, For each power semiconductor element that outputs different potentials, it is necessary to insulate against a metal plate provided in contact with the heat sink (a metal plate provided in common to the first and second power semiconductor elements). Therefore, in the present invention, an insulating layer is provided between each power semiconductor element and the metal plate.
On the other hand, when the insulating layer is provided in this manner, the thermal resistance increases in the insulating layer (the thermal conductivity is deteriorated), and it becomes difficult to dissipate the transient heat generated at the time of instantaneous drop well. Therefore, in the present invention, a plurality of heat spreaders provided separately for each power semiconductor element are joined to each power semiconductor element, and an insulating layer is interposed between the heat spreader and the metal plate.
Thereby, the transient heat generation of the power semiconductor element can be diffused in the in-plane direction by the heat spreader bonded to each of the power semiconductor elements, and a rapid temperature rise of the power semiconductor element can be suppressed. Furthermore, since the heat diffused in the in-plane direction by the heat spreader is dissipated by the heat sink disposed via the metal plate, the maximum temperature achieved by the temperature increase of the power semiconductor element can be lowered.

  Further, according to this configuration, it is possible to radiate heat from a plurality of power semiconductor elements having different output potentials and different heat generation timings with a single heat sink. Therefore, it is possible to realize an instantaneous voltage drop compensator that is small and light in weight and can be easily incorporated into other devices.

Here, each of the heat spreaders is preferably composed of a copper plate having a thickness of 1 mm or more, and heat generated in the power semiconductor element can be suitably diffused by the endothermic effect of the copper plate.
According to this configuration, it is possible to quickly absorb the transient heat generated at the time of a sag and effectively suppress the temperature rise of the power semiconductor element.

Each of the power semiconductor elements that output different potentials may further include a bonding layer that is provided separately between each of the plurality of heat spreaders and the insulating layer, and bonds each heat spreader to the insulating layer. You may comprise.
According to this configuration, even when it is difficult to join the heat spreader and the insulating layer, the heat spreader and the insulating layer are joined via the joining layer, so that heat can be transferred from the heat spreader to the metal plate and the heat sink. Can be conducted efficiently.

It is preferable that the contact surface of the heat sink that contacts the other main surface of the metal plate has a plane size equal to or larger than the other main surface of the metal plate.
According to this configuration, the thermal resistance between the metal plate and the heat sink can be reduced, and heat can be efficiently conducted from the metal plate to the heat sink.

Further, a hollow case that engages with an end of the metal plate and accommodates the first and second power semiconductor elements, the heat spreader, and the insulating layer in an opening may be further provided.
According to this configuration, the members constituting the compensation voltage generation circuit excluding the system changeover switch circuit and the power storage unit, that is, the first and second power semiconductor elements, the heat spreader, and the insulating layer are accommodated in the case. Thus, the instantaneous voltage drop compensator can be configured compactly and easily incorporated into other devices.

Further, the system changeover switch circuit and the compensation voltage generation circuit are provided on the same substrate, and the power module (configured by integrating the first and second power semiconductor elements, the metal plate, the heat spreader, the insulating layer, and the heat sink) and the compensation voltage. The compensation capacitor for storing the power for generating the power may be mounted on the same side of the substrate.
According to this configuration, by arranging the power module and the compensation capacitor together on one side of the substrate, the other side of the substrate can be made a non-mounting surface. This is effective in reducing weight.

Further, it is preferable to form the power module so that the height of the power module is equal to or less than the height of the compensation capacitor in the normal direction of the substrate.
According to this configuration, the power module is accommodated in a space on the substrate region other than the substrate region on which the compensation capacitor is mounted (a space on the substrate region formed from the substrate mounting surface to the height of the compensation capacitor or less). Thus, the instantaneous voltage drop compensator can be further miniaturized. That is, such a space often becomes a dead space when incorporated in other equipment, but by accommodating the power module in the space, the space can be effectively used to further reduce the instantaneous voltage drop compensation device. Can be achieved.

  According to the present invention, it is possible to provide an instantaneous voltage drop compensator that can effectively use a heat sink, can be reduced in size and weight, and can be easily incorporated into other devices.

  A preferred embodiment of an instantaneous voltage drop compensator according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a circuit diagram of an instantaneous voltage drop compensator according to the present invention. The instantaneous voltage drop compensator 1 is always a commercial power supply type, and includes a system changeover switch circuit 2 and a compensation voltage generation circuit 3.
Among these, the system changeover switch circuit 2 includes at least one first power semiconductor element Q ₅ , Q ₆ , and connects the commercial power supply 4 and the load 5 to supply the power of the commercial power supply 4 to the first power semiconductor element Q ₅ , supplies all times to the load 5 through Q _6, disconnect the commercial power source 4 and a load 5 in instantaneous drop occurs during, interrupting the power supply from the commercial power source 4.
The compensation voltage generation circuit 3 includes a plurality of second power semiconductor elements Q _{1 to} Q ₄ and a compensation capacitor C (corresponding to “power storage unit”) that accumulates electric power for compensating for a sag. The electric power stored in the compensation capacitor C when a voltage sag occurs is converted into AC power using a plurality of second power semiconductor elements Q _{1 to} Q ₄ and supplied to the load.
Since the instantaneous voltage drop compensator 1 according to the present invention and the conventional instantaneous voltage drop compensator 1 ′ have the same circuit configuration, the specific circuit configuration of the instantaneous voltage drop compensator 1 according to the present invention and A description of the operation is omitted.

FIG. 2 is an external perspective view of the instantaneous voltage drop compensator 1 according to the present invention. The instantaneous voltage drop compensation device 1 includes a substrate 6, a power module 10 mounted on the substrate 6, and a compensation capacitor C such as an electrolytic capacitor, an electric double layer capacitor, and an electrochemical capacitor. That is, the system changeover switch circuit 2 and the compensation voltage generation circuit 3 are provided on the same substrate. The power module 10 and the compensation capacitor C are both disposed on the one surface (front surface) 6 a side of the substrate 6. On the other hand, the other surface (back surface) 6b side of the substrate 6, the conventional apparatus large part of the heat sink H ₅ and the like in (see FIG. 8) is not arranged. Further, the height of the power module 10 (the dimension in the normal direction of the substrate 6) is equal to or less than that of the compensation capacitor C (in this embodiment, the height is lower than that of the compensation capacitor C). For this reason, the instantaneous voltage drop compensator 1 can be reduced in size, and can be easily attached to and incorporated in other devices.

As shown in FIG. 3, the power module 10 abuts against a hollow and square case 11, a metal plate 13 fitted in the opening of the case 11, and a surface (the other main surface) 13 b side of the metal plate 13. A heat sink H is provided. The case 11 is engaged with the end of the metal plate 13 and each member (the first power semiconductor elements Q ₅ , Q ₆ and the first power semiconductor elements Q ₅ and Q ₆₎ constituting the compensation voltage generation circuit 3 excluding the system changeover switch circuit 2 and the compensation capacitor C. In addition to the two-power semiconductor elements Q _{1 to} Q ₄ , a heat spreader, an insulating layer, etc. described later) are accommodated in the opening. Here, the heat sink H is composed of a single block body having substantially the same plane size as the case 11 from the viewpoint of achieving both the reduction in the instantaneous voltage drop compensator and the heat radiation efficiency. The case 11 and the heat sink H are appropriately screwed. Below the case 11, a plurality of external terminals (electrode terminals) 12 for electrically connecting the power module 10 and the substrate 6 are provided. The case 11 is made of an insulating resin, and the metal plate 13 and the heat sink H are made of copper or aluminum having a high thermal conductivity.

In this embodiment, the first power semiconductor elements Q ₅ and Q ₆ are driven only during normal operation, while the second power semiconductor elements Q _{1 to} Q ₄ are driven only during a momentary drop. That is, the first power semiconductor element and the second power semiconductor element are not driven simultaneously. For this reason, during normal operation, it is sufficient to consider only the steady heat generation without considering the transient heat generation at the time of a sag, and the heat sink is made effective by dissipating heat with the single heat sink H as described above. It can be used.

4A is a perspective view of the case 11 and the metal plate 13 shown in FIG. 3 that are vertically inverted, and FIG. 4B is an exploded perspective view of FIG. 4A. On the back surface (one main surface) 13a side of the metal plate 13, that is, on the opposite surface side facing the substrate 6, chip-shaped first and second power semiconductor elements Q _{1 to} Q _{5 to be} radiated, etc. (power semiconductor element Q _{6 to} Q ₈ are mounted, and heat spreaders HS _{1 to} HS ₅ are provided directly below each power semiconductor element (between each power semiconductor element and the metal plate) corresponding to each power semiconductor element. Be joined. That is, while the metal plate 13 is provided in common to the first power semiconductor device _{Q 5} and the second power semiconductor elements _Q 1 to Q _4, a plurality of heat spreader _HS 1 _{~HS 5} are separated from each other for each power semiconductor element Is provided.

  A cross-sectional view taken along line XX in FIG. 4B is shown in FIG. The metal plate 13 is positioned with respect to the case 11 using a step provided at the opening of the case 11. In addition, the heat sink H contacts only the surface 13 b of the metal plate 13 and does not contact the case 11. The abutment surface of the heat sink H that abuts against the surface 13b of the metal plate 13 (the surface opposite to the side from which the fins protrude) has a planar size that is equal to or greater than that of the surface 13b of the metal plate 13. Therefore, the thermal resistance between the metal plate 13 and the heat sink H can be reduced, and the heat from the metal plate 13 can be efficiently propagated to the heat sink H.

Since the configuration related to the mounting of the power semiconductor elements Q _{1 to} Q _{5 and the} like on the metal plate 13 is the same, here, the power semiconductor element Q ₁ will be described with reference to FIG. The power semiconductor element Q ₁ is bonded to the heat spreader HS ₁ via the solder layer 16. A diode D ₁ connected between the collector and emitter of the power semiconductor element Q ₁ is also joined to the heat spreader HS ₁ via the solder layer 16. The heat spreader HS ₁ is preferably made of a copper plate having a thickness of 1 mm or more, and heat generated by the power semiconductor element Q ₁ and the diode D ₁ can be quickly diffused in the in-plane direction by the heat absorption effect of the copper plate. Thus, it is possible to effectively suppress the temperature rise of the power semiconductor element Q ₁ to rapidly absorb transient heat generated by the power semiconductor device Q ₁ and diode D ₁ is driven when an instantaneous drop .

The heat spreader HS ₁ is bonded to the pattern layer 15 via the solder layer 17. The pattern layer 15 is bonded to the insulating layer 14, and the insulating layer 14 is bonded to the back surface side of the metal plate 13. Further, a wire made of aluminum or the like is bonded to the pattern layer 15 so as to be electrically connected to the external terminal 12 formed integrally with the case 11. The connection with the external terminal 12 is not limited to the case where a wire is bonded to the pattern layer 15, and the wire may be bonded to the heat spreader HS ₁ .

The pattern layer 15 is provided from the viewpoint of satisfactorily bonding the heat spreaders HS _{1 to} HS ₅ and the insulating layer 14. That is, the pattern layer 15 is provided separately between each of the plurality of heat spreaders HS _{1 to} HS ₅ and the insulating layer 14, and functions as a bonding layer that bonds each heat spreader and the insulating layer 14. By providing such a pattern layer 15, heat can be efficiently transferred from the heat spreaders HS _{1 to} HS ₅ to the metal plate 13. In addition, the pattern layer 15 in this embodiment has a function as a wiring layer for electrically connecting elements such as the power semiconductor elements Q _{1 to} Q ₅ in addition to a function as a bonding layer. . Pattern layer 15 is not limited to the case of providing each heat spreader _HS 1 _{~HS 5,} each power semiconductor element for outputting a different potentials of the power semiconductor elements _Q 1 to Q _5, a plurality of heat spreader _HS 1 _{~HS 5} It suffices if they are provided separately from each other and between the insulating layers 14.

The thickness of the pattern layer 15 is set to be smaller than the thickness of the heat spreader (for example, a copper plate) from the viewpoint of solving the following problems caused by the thickness of the metal layer (for example, the copper layer) immediately above the insulating layer 14. That is, when the thickness of the metal layer immediately above the insulating layer 14 is increased, the reflow or the like causes warpage of the metal layer due to the thermal effect, which adversely affects the adhesion between the insulating layer 14 and the metal layer. Will be affected.
Therefore, in this embodiment, the thickness of the pattern layer 15 is set sufficiently thin with respect to the thickness of the heat spreader (for example, 1 mm or more) (depending on the current capacity flowing through the pattern, about 70 to 120 μm). In this way, by inserting the pattern layer 15 having a relatively small thickness between the heat spreader and the insulating layer 14, the heat spreader having a large thickness can improve heat dissipation (heat diffusion in the in-plane direction), but can be insulated. The problem (deterioration of adhesion between the insulating layer and the metal layer) due to the arrangement of the metal layer having a large thickness immediately above the layer 14 can be solved. In addition, by setting the thickness of the pattern layer 15 to be relatively small, the amount of useless metal that does not contribute to heat dissipation is reduced, and production defects due to wire bonding due to fluctuations in the thickness of the metal layer occur. Can be prevented.

  The pattern layer 15 is designed with a pattern width that allows a necessary current to flow at the time of normal energization or at the time of sag compensation. Further, since the instantaneous voltage drop compensator is used for compensation of a relatively high commercial power supply of AC 100 V or AC 200 V, the interval between the high voltage side pattern to which the high voltage is applied and the low voltage side pattern to which the low voltage is applied is AC1. It is desirable to secure an insulation distance having a dielectric breakdown voltage performance of 0.5 KV, 1 minute or AC 2 kV, 1 minute. The insulating layer 14 inserted between the pattern layer 15 and the metal plate 13 generally uses an epoxy insulating resin containing a highly thermally conductive filler. If high thermal conductivity is required, the insulating layer 14 is filled with filler. An insulating layer whose amount is increased to about 40 wt% can also be used.

  The adhesion of the pattern layer 15 and the insulating layer 14 to the metal plate is performed by sandwiching an insulating sheet formed in advance into a sheet shape between the metal plate 13 and the copper foil (pattern layer material), and heating / pressurizing them. And glue. The pattern layer 15 is formed by exposing the pattern portion after this adhesion and performing an etching process.

A large heat sink H is provided on the surface 13 b side of the metal plate 13. Thus, the heat diffusion in the plane direction at the heat spreader HS _1, it is possible to heat dissipation by the heat sink H disposed through the metal plate 13, reducing the maximum temperature reached by the temperature rise of the power semiconductor device Q ₁ be able to.

  After all, according to the configuration shown in FIG. 5, the transient heat generation of the power semiconductor element is diffused in the in-plane direction by the heat spreader and quickly dissipated (see arrow α in FIG. 6). The rise can be suppressed. Thereby, for example, it is possible to suppress an abrupt increase in temperature between about 0.2 seconds after the occurrence of a sag. Furthermore, since the heat diffused in the in-plane direction by the heat spreader can be dissipated by the heat sink, the maximum temperature achieved by the temperature rise of the power semiconductor element can be lowered (see arrow β in FIG. 6). In addition, since transient heat generation is sufficiently diffused by the heat spreader's endothermic effect (since rapid temperature rise is suppressed), a decrease in thermal conductivity due to the arrangement of the heat sink through the insulating layer is hardly a problem. .

Further, according to the configuration shown in FIG. 5, since the insulating layer is interposed between the heat spreader and the metal plate, different potentials are applied to the metal plate provided in common for each power semiconductor element. Can be insulated from each other (for example, Q ₁ and Q ₃ ), and the power semiconductor elements can be prevented from being energized with each other.
On the other hand, if an insulating layer is provided in this way, the thermal resistance of the insulating layer increases (the thermal conductivity deteriorates), and it may be difficult to dissipate transient heat generated at the time of instantaneous drop well. It is. However, in this embodiment, as described above, the heat spreader provided separately from each other for each power semiconductor element is joined to each power semiconductor element, so that the transient heat generated at the time of instantaneous drop is absorbed and diffused by the heat spreader. And a rapid temperature rise of the power semiconductor element can be suppressed.

  As described above, according to this embodiment, a plurality of power semiconductor elements having different output potentials and different heat generation times can be radiated by one heat sink. Therefore, it is possible to realize an instantaneous voltage drop compensator that is small and light in weight and can be easily incorporated into other devices.

Even in the conventional instantaneous voltage drop compensator, it is conceivable to change the configuration as shown in FIG. At this time, when there are discrete type components (power semiconductor elements) that output different potentials, it is necessary to place the insulating sheet 8 between the discrete type components Q _{1 to} Q ₅ and the heat sink H instead of the thermal compound. There is. However, the insulating sheet 8 has a low thermal conductivity, and the heat generated by the discrete components Q _{1 to} Q ₅ is quickly diffused to the heat sink H and cannot be dissipated.

In order to solve such a problem, it is conceivable to insert a heat spreader between the insulating sheet 8 and each of the discrete components Q _{1 to} Q ₅ , but this is not realistic for the following reason. That is, (i) it is difficult to join each discrete part Q _{1 to} Q ₅ (usually the joining surface is formed of copper) and the heat spreader by soldering or the like, and there is a problem in the fixing method of the heat spreader. . (Ii) In relation to the problem of such a fixing method, a relatively large thermal resistance is generated between each discrete component Q _{1 to} Q ₅ and the heat spreader and between the heat spreader and the insulating sheet 8. and it will, eventually, rapidly absorb heat generated from the discrete component Q ₁ to Q _5, can not be diffused.
From the above, from the viewpoint of configuring a small instantaneous voltage drop compensator with a large output, the configuration as shown in FIG. 9 cannot be adopted.

As mentioned above, although preferred embodiment of the instantaneous voltage drop compensation apparatus based on this invention was described, this invention is not limited to the said structure.
For example, the compensation voltage generation circuit 3 is not limited to the single-phase inverter shown in FIG. 1, but can be a three-phase inverter having U, V, and W phase outputs.

It is a circuit diagram of an instantaneous voltage drop compensation device. 1 is an external perspective view of an instantaneous voltage drop compensation device according to the present invention. It is a disassembled perspective view of the power module which concerns on this invention. It is the case and metal plate which concern on this invention, Comprising: (A) is a perspective view of the state which reversed FIG. 3 up and down, (B) is an exploded perspective view of (A). FIG. 6 is a cross-sectional view taken along line XX in FIG. It is the graph which contrasted the temperature change of the power semiconductor element in the conventional instantaneous voltage drop compensation apparatus and the instantaneous voltage drop compensation apparatus which concerns on this invention. A power semiconductor element used in a conventional instantaneous voltage drop compensator and a heat sink attached thereto, wherein (A) is an exploded perspective view, and (B) and (C) are states in which the power semiconductor element and the heat sink are attached, respectively. It is a front view and a side view. It is an external appearance perspective view of the conventional instantaneous voltage drop compensation apparatus. It is a disassembled perspective view of the other conventional instantaneous voltage drop compensation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Instantaneous voltage drop compensation apparatus 2 System changeover switch circuit 3 Compensation voltage generation circuit 4 Commercial power supply 5 Load 6 Substrate 7 Spacer 8 Insulation sheet 10 Power module 11 Case 12 External terminal 13 Metal plate 14 Insulation layer 15 Pattern layer 16 Solder layer 17 Solder layer C compensation capacitor _{D, D} 1 ~D ₉ diode _{H, H} 1 _{~H 5} heat sink _HS 1 _{~HS 5} spreader _{Q, Q} 1 ~Q ₇ power semiconductor element

Claims (7)

Having at least one first power semiconductor element, connecting a commercial power source and a load during normal operation to supply power of the commercial power source to the load via the first power semiconductor element, and at the time of instantaneous voltage drop A system switch circuit for cutting off power supply from the commercial power source to the load;
A power storage unit that stores power and a plurality of second power semiconductor elements, and when an instantaneous voltage drop occurs, a compensation voltage is generated from the power stored in the power storage unit using the plurality of second power semiconductor elements. A compensation voltage generation circuit for supplying the load;
In the instantaneous voltage drop compensator with
A metal plate that is provided in common to the first and second power semiconductor elements, and both the first and second power semiconductor elements are mounted on one main surface side;
A plurality of heat spreaders provided separately from each other for each of the first and second power semiconductor elements, and joined to each power semiconductor element;
An insulating layer interposed between each of the heat spreaders and the metal plate;
A heat sink provided in contact with the other main surface of the metal plate;
An instantaneous voltage drop compensation device comprising:   2. The instantaneous voltage drop compensator according to claim 1, wherein each of the heat spreaders is made of a copper plate having a thickness of 1 mm or more.   Each of the first and second power semiconductor elements that outputs different potentials is provided between each of the plurality of heat spreaders and the insulating layer, and each heat spreader and the insulating layer The instantaneous voltage drop compensation device according to claim 1, further comprising a bonding layer that bonds the two.   The contact surface of the heat sink that contacts the other main surface of the metal plate has a plane size equal to or larger than that of the other main surface of the metal plate. The instantaneous voltage drop compensator described in 1.   2. A hollow case that engages with an end of the metal plate and accommodates the first and second power semiconductor elements, the heat spreader, and the insulating layer in an opening. 4. The instantaneous voltage drop compensator according to any one of 4 above. The system switching switch circuit and the compensation voltage generation circuit are provided on the same substrate,
The power storage unit includes a compensation capacitor that stores power for generating the compensation voltage,
The case, the first and second power semiconductor elements housed in the case, the heat spreader and the insulating layer, the metal plate engaged with the case, and the heat sink abutted on the metal plate Integrated into a power module,
6. The instantaneous voltage drop compensator according to claim 5, wherein the power module and the compensation capacitor are mounted on the same side of the substrate.   The instantaneous voltage drop compensator according to claim 6, wherein a height of the power module is formed to be equal to or less than a height of the compensation capacitor in a normal direction of the substrate.

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