JP2022163572A - Uninterruptible power supply - Google Patents

Abstract

To provide an uninterruptible power supply that can be reduced in size.SOLUTION: An uninterruptible power supply comprises: a plurality of first and second semiconductor modules including semiconductor devices for performing power conversion; and a heat sink for cooling the plurality of first and second semiconductor modules. The heat sink includes a base part for mounting the plurality of first and second semiconductor modules, and a fin part connected with the base part. The plurality of first and second semiconductor modules are provided respectively on an inflow port surface and an outflow port surface of cooling air from the fin part. A longitudinal direction of the plurality of first semiconductor modules is provided to be perpendicular to an inflow direction of the cooling air from the fin part from the inflow port surface to the outflow port surface. A longitudinal direction of the plurality of second semiconductor modules is provided to be parallel to the inflow direction of the cooling air from the fin part.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to uninterruptible power supplies.

Conventionally, an uninterruptible power supply includes a converter that converts an AC voltage into a DC voltage, and an inverter that converts the DC voltage from the converter back into an AC voltage and outputs the AC voltage to a load.

Power semiconductor modules composed of IGBTs (Insulated Gate Bipolar Transistors), diodes, and the like are used in converters, inverters, and the like.

During the operation of the uninterruptible power supply, these power semiconductor modules generate heat due to conduction loss caused by current flow and switching loss caused by switching, and the element temperature rises. If the temperature of the power semiconductor module exceeds the rated temperature, the internal circuits will be degraded or destroyed.

Therefore, the power semiconductor module is arranged on one side of the heat sink, the other side of the heat sink is provided with cooling fins, and the cooling fins are blown by the cooling fan to dissipate the heat of the power semiconductor elements. Various methods have been proposed for arranging them on a heat sink (see Patent Documents 1 to 3).

Patent No. 5558401 JP-A-2003-259658 Patent No. 5715352

In this respect, further improvements are needed in terms of the arrangement of power semiconductor modules for converters and inverters on heat sinks.

The present disclosure has been made to solve the above problems, and provides an uninterruptible power supply that can be downsized.

An uninterruptible power supply according to a certain aspect includes semiconductor elements, a plurality of first and second semiconductor modules for power conversion, and a heat sink for cooling the plurality of first and second semiconductor modules. . The heat sink includes a base portion for mounting the plurality of first and second semiconductor modules, and a fin portion connected to the base portion. The plurality of first and second semiconductor modules are provided on the cooling air inlet surface side and the cooling air outlet surface side of the fin portion, respectively. The longitudinal direction of the plurality of first semiconductor modules is provided so as to be perpendicular to the inflow direction of the cooling air of the fin portion from the inlet surface side to the outlet surface side. The longitudinal direction of the plurality of second semiconductor modules is provided so as to be parallel to the inflow direction of the cooling air of the fin portion.

The plurality of first semiconductor modules are converters that convert AC voltage into DC voltage, and the plurality of second semiconductor modules are inverters that convert DC voltage into AC voltage.

Each of the plurality of first and second semiconductor modules includes one IGBT element.

The plurality of first semiconductor modules are provided on the cooling air inlet surface side of the fin portion. The plurality of second semiconductor modules are provided on the cooling air outlet surface side of the fin portion.

According to one embodiment, the uninterruptible power supply can be miniaturized.

It is a figure explaining circuit composition of uninterruptible power supply 1 based on an embodiment. 3 is a diagram illustrating the configuration of a power conversion unit including a converter CNV, an inverter INV, and an electrolytic capacitor 11 according to the embodiment; FIG. FIG. 10 is a diagram illustrating the configuration of a heat sink 50 of a converter CNV and an inverter INV based on a comparative example; 4 is a diagram illustrating the configuration of a heat sink 60 of a converter CNV and an inverter INV based on the embodiment; FIG. FIG. 10 is a diagram for explaining the flow of cooling air in a heat sink 50 based on a comparative example; FIG. 4 is a diagram illustrating the flow of cooling air in the heat sink 60 based on the embodiment; FIG. 5 is a diagram illustrating temperature changes of heat sinks 50 and 60 due to cooling air based on the embodiment and a comparative example; FIG. 5 is a diagram for explaining temperature distribution of a base portion 100 of a heat sink 50 based on a comparative example; 4 is a diagram illustrating temperature distribution of a base portion 100 of a heat sink 60 based on an embodiment; FIG. FIG. 10 is a diagram illustrating the configuration of a heat sink 70 of a converter CNV and an inverter INV based on another embodiment; FIG. 10 is a diagram illustrating temperature distribution of a base portion 100 of a heat sink 50 based on another embodiment;

This embodiment will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are given the same reference numerals, and the description thereof will not be repeated.

Drawing 1 is a figure explaining circuit composition of uninterruptible power supply 1 based on an embodiment.
As shown in FIG. 1 , uninterruptible power supply 1 is connected to AC input power 2 , bypass input power 3 and load 4 . The uninterruptible power supply 1 is also connected to the storage battery 31 via the switch 14 .

The AC input power supply 2 and the bypass input power supply 3 are AC power supplies that supply AC power to the uninterruptible power supply 1 . Each of these input power supplies is composed of, for example, a commercial AC power supply or a private power generator.

A single-phase single-wire (1φ1W) system is shown as an example of an input AC power supply. However, the type of input AC power supply is not limited to the single-phase single-wire system, and may be, for example, a three-phase three-wire power supply or a single-phase three-wire power supply.

The uninterruptible power supply 1 includes a bypass input terminal T1, an AC input terminal T2, a storage battery terminal T3, and an output terminal T4.

A bypass input terminal T1 receives AC power from the bypass input power supply 3 . AC input terminal T2 receives AC power from AC input power supply 2 . The storage battery terminal T3 is connected to the positive electrode of the storage battery 31 via the switch 14 . A load 4 is connected to the output terminal T4.

The uninterruptible power supply 1 includes electromagnetic contactors (contactors) 5, 15, 17, reactors 7, 9, a converter CNV, an electrolytic capacitor 11, an inverter INV, capacitors 8, 10, a thyristor switch 18, and a control device 30 .

Among these, the contactor 5, reactors 7 and 9, inverter INV, converter CNV, and contactor 15 are connected in series between AC input terminal T2 and output terminal T4.

Contactor 5 and reactor 7 are inserted and connected to an energization path between AC input terminal T2 and converter CNV. A capacitor 8 is connected to the contactor 5 in parallel with the reactor 7 . The contactor 5 opens (turns on) and closes (turns off) in response to commands from the controller 30 . Capacitor 8 and reactor 7 are filters for removing harmonics and high frequencies of AC power input to and output from converter CNV.

Converter CNV converts AC power supplied from AC input power supply 2 into DC power. Electrolytic capacitor 11 smoothes the output voltage of converter CNV. Inverter INV converts the DC power smoothed by electrolytic capacitor 11 into AC power having a predetermined voltage and a predetermined frequency. Each of converter CNV and inverter INV is controlled by control device 30 .

The contactor 15 and the reactor 9 are inserted and connected to an energization path between the output terminal T4 and the inverter INV. Capacitor 10 is connected to contactor 15 in parallel with reactor 9 . The contactor 15 opens (turns on) and closes (turns off) in response to commands from the controller 30 . The contactor 15 and the reactor 9 are filters for removing harmonics and high frequencies from AC power input to and output from the inverter INV.

The contactor 15 switches the AC output from the output terminal T4 to the load 4 between the output of the inverter INV and the output of the bypass circuit composed of the thyristor switch 18 and the contactor 17. FIG.

Thyristor switch 18 and contactor 17 are connected in parallel between bypass input terminal T1 and output terminal T4. The thyristor switch 18 is a switch for rapidly switching the AC power output from the output terminal T4 to the load 4 from the output of the inverter INV to the AC power from the bypass input power supply 3 . The contactor 17 is inserted and connected to the current path from the bypass input terminal T1 to the output terminal T4. The contactor 17 is for maintaining the AC power from the bypass input power supply 3 as an AC output from the uninterruptible power supply. Contactor 15 , thyristor switch 18 and contactor 17 are closed (on) and open (off) in response to commands from controller 30 .

Storage battery 31 is a power storage device for supplying DC power to inverter INV when AC input power supply 2 cannot supply AC power (for example, during a power failure). Reactor 12 and switch 14 are connected in series with storage battery 31 . Reactor 12 is provided to prevent rush current to storage battery 31 .

When AC power is normally supplied from AC input power supply 2 , DC power generated by converter CNV is stored in storage battery 31 and converted to AC power by inverter INV and supplied to load 4 . On the other hand, during a power outage when the supply of AC power from the AC input power supply 2 is stopped, the operation of the converter CNV is stopped, and the DC power stored in the storage battery 31 is converted into AC power by the inverter INV and supplied to the load 4. . Therefore, according to the uninterruptible power supply, the operation of the load 4 can be continued using the electric power stored in the storage battery 31 even during a power failure.

Control device 30 is a control device for controlling converter CNV and inverter INV in order to generate AC power to be supplied to load 4 during normal operation and power failure. , ROM (Read Only Memory) and RAM (Random Access Memory). Control device 30 controls converter CNV, inverter INV and the like by causing CPU to read a program stored in ROM or the like in advance into RAM and execute the program.

Further, control device 30 controls contactors 5, 15, 17 and a bypass circuit in addition to controlling converter CNV and inverter INV. At least part of the control device 30 may be configured to execute predetermined numerical value/logic operation processing by hardware such as an electronic circuit.

FIG. 2 is a diagram illustrating a configuration of a power conversion unit including converter CNV, inverter INV, and electrolytic capacitor 11 according to the embodiment.

Referring to FIG. 2, the power conversion unit includes a plurality of semiconductor elements (IGBT) QA1-QA4, QA1#-QA4#, capacitor units CD1, CD2, resistor units RCD1, RCD2, and bus lines L1, L2. include. The configuration of each semiconductor element (IGBT) is the same.

Semiconductor elements (IGBTs) QA1-QA4 forming converter CNV are connected in common to the input terminal and respectively connected between bus line L1 and bus line L2.

A plurality of semiconductor elements (IGBTs) QA#1 to QA#4 forming the inverter INV are connected in parallel between the bus line L1 and the bus line L2, and their outputs and output terminals are commonly connected.

Capacitor units CD1 and CD2 are connected in parallel between bus L1 and bus L2.

Resistance units RCD1 and RCD2 are connected in parallel between bus L1 and bus L2.
FIG. 3 is a diagram illustrating the configuration of heat sink 50 of converter CNV and inverter INV based on a comparative example.

As shown in FIG. 3A, the layout configuration of a plurality of semiconductor elements (IGBTs) QA of the base portion 100 of the heat sink 50 is shown.

A plurality of semiconductor elements QA are provided on the cooling air inlet surface side and the cooling air outlet surface side of the fin portion 200, respectively. The plurality of semiconductor elements QA has a two-stage structure arranged on the front side and the back side.

The heat sink 50 shown in FIG. 3(B) is an example of the structure, and includes a base portion provided on the upper portion and a comb-shaped fin portion on the lower portion. Note that the fins are not limited to this, and lattice-shaped fins, wave-shaped fins, or the like may be used.

As an example, a plurality of metal pieces are provided at predetermined intervals so that the cooling air can be received from one side surface (inflow port) and discharged to the opposite side surface (outflow port). It is possible to cool the temperature of the base portion connected to the fin portion by passing the cooling air through the fin portion.

All of the plurality of semiconductor elements QA are oriented in the same direction, and the longitudinal direction is arranged along the inflow direction of the cooling air.

FIG. 4 is a diagram illustrating the configuration of the heat sink 60 of the converter CNV and the inverter INV based on the embodiment.

As shown in FIG. 4A, the layout configuration of a plurality of semiconductor elements (IGBTs) QA of the base portion 100 of the heat sink 60 is shown.

As shown in FIG. 4B, the heat sink 50 is provided with a base portion on the upper portion and a comb-shaped fin portion on the lower portion.

The layout configuration of the semiconductor element QA is different from that of the heat sink 50 described with reference to FIG. Specifically, the plurality of semiconductor elements QA are provided on the cooling air inlet surface side and the cooling air outlet surface side of the fin portion 200, respectively. The plurality of semiconductor elements QA has a two-stage structure arranged on the front side and the back side. The plurality of semiconductor elements QA are not all oriented in the same direction, and the longitudinal direction of the plurality of semiconductor elements QA arranged on the inlet surface side (the front side) is arranged perpendicular to the inflow direction of the cooling air. The longitudinal direction of the plurality of semiconductor elements QA arranged on the outlet surface side (rear side) is arranged in parallel along the inflow direction of the cooling air.

As an example, semiconductor elements QA1 to QA4 forming converter CNV are arranged on the inlet face side (front side). On the other hand, the semiconductor elements QA#1 to QA#4 forming the inverter INV are arranged on the outflow surface side (back side). In this example, the semiconductor elements QA1 to QA4 forming the converter CNV are arranged on the inlet surface side (front side), and the semiconductor elements QA#1 to QA#4 forming the inverter INV are arranged on the outlet surface side ( Although the case of arranging them on the back side) will be described, they may be arranged in an interchangeable manner. In this respect, comparing the heat generation of the semiconductor elements, the semiconductor element with the higher heat generation is arranged on the inlet surface side (front side), and the semiconductor element with the lower heat generation amount is arranged on the outlet surface side (rear side). Placement is desirable.

FIG. 5 is a diagram illustrating the flow of cooling air in the heat sink 50 based on the comparative example.
Referring to FIG. 5, a plurality of semiconductor elements QA are provided on the cooling air inlet surface side and the cooling air outlet surface side of fin portion 200, respectively. The plurality of semiconductor elements QA has a two-stage structure arranged on the front side and the back side. Here, a cross-sectional line DA of a plurality of semiconductor elements QA arranged on the back side and a cross-sectional line DB of a plurality of semiconductor elements QA arranged on the front side are shown.

The cooling air flows in from the inlet surface side of the heat sink 50 and is discharged from the outlet surface side. The heat of the semiconductor element QA arranged on the front side of the base portion 100 is cooled by the fin portion 200 by the cooling air. On the other hand, the cooling air containing the heat passes through the fin portion 200 corresponding to the semiconductor element QA arranged on the back side of the base portion 100 . Therefore, the heat of the semiconductor element QA arranged on the back side of the base portion 100 is cooled by the fin portion 200 with the warmed cooling air.

FIG. 6 is a diagram illustrating the flow of cooling air in the heat sink 60 based on the embodiment.

Referring to FIG. 6, a plurality of semiconductor elements QA are provided on the cooling air inlet surface side and the cooling air outlet surface side of fin portion 200, respectively. The plurality of semiconductor elements QA has a two-stage structure arranged on the front side and the back side. Here, a cross-sectional line DC of a plurality of semiconductor elements QA arranged on the back side and a cross-sectional line DD of a plurality of semiconductor elements QA arranged on the front side are shown.

The cooling air flows in from the inlet surface side of the heat sink 50 and is discharged from the outlet surface side. The heat of the semiconductor element QA arranged on the front side of the base portion 100 is cooled by the fin portion 200 by the cooling air. On the other hand, the cooling air containing the heat passes through the fin portion 200 corresponding to the semiconductor element QA arranged on the back side of the base portion 100 . Therefore, the heat of the semiconductor element QA arranged on the back side of the base portion 100 is cooled by the fin portion 200 with the warmed cooling air.

Here, the configuration of the heat sink 60 is such that the longitudinal direction of the plurality of semiconductor elements QA arranged on the front side is arranged perpendicular to the inflow direction of the cooling air. On the other hand, the longitudinal direction of the plurality of semiconductor elements QA arranged on the outlet surface side (back side) is arranged in parallel along the inflow direction of the cooling air.

Therefore, the cooling air that has passed through the fin portions 200 for the semiconductor elements QA arranged on the front side of the base portion 100 all passes through the fin portions 200 corresponding to the semiconductor elements QA arranged on the back side of the base portion 100. Instead, the fin portion 200 cools the region in which the arrangement overlaps with the inflow direction of the cooling air by the heated cooling air.

FIG. 7 is a diagram illustrating temperature changes of the heat sinks 50 and 60 caused by cooling air based on the embodiment and the comparative example.

Referring to FIG. 7, the vertical axis indicates temperature T. As shown in FIG. The horizontal axis indicates the position of the heat sink. In this example, the heatsink is shown from the left end to the right end.

As shown in the figure, when comparing the comparative example and the embodiment, the cross-sectional line DA and the cross-sectional line DC are at the same position. Section line DB and section line DD are at the same position.

In this example, temperature change waveforms M1 to M4 are shown on cross-sectional lines DA to DD, respectively.

As shown in the temperature change waveform, the local maximum temperature is lower in the embodiment than in the comparative example. That is, the temperature is distributed without being locally concentrated. Therefore, it can be seen that the cooling effect is clearly higher in the embodiment than in the comparative example.

FIG. 8 is a diagram illustrating the temperature distribution of the base portion 100 of the heat sink 50 based on the comparative example.

FIG. 9 is a diagram illustrating the temperature distribution of the base portion 100 of the heat sink 60 based on the embodiment.

With reference to FIGS. 8 and 9, the temperature elevation is shown in grayscale. The black part indicates the case where the temperature is high, and the white part indicates the case where the temperature is low.

It can be seen that the embodiment has a wider white temperature region than the comparative example, and clearly has a higher cooling effect.

Therefore, the heat dissipation capability of the heat sink can be fully utilized, and the size of the heat sink itself can be reduced.

FIG. 10 is a diagram illustrating the configuration of heat sinks 70 of converter CNV and inverter INV according to another embodiment.

As shown in FIG. 10A, the layout configuration of a plurality of semiconductor elements (IGBTs) QA of the base portion 100 of the heat sink 70 is shown.

As shown in FIG. 10B, the heat sink 70 is provided with a base portion on the upper portion and a comb-shaped fin portion on the lower portion.

The layout configuration of the semiconductor element QA is different from that of the heat sink 50 described with reference to FIG. Specifically, the plurality of semiconductor elements QA are provided on the cooling air inlet surface side and the cooling air outlet surface side of the fin portion 200, respectively. The plurality of semiconductor elements QA has a two-stage structure arranged on the front side and the back side. The plurality of semiconductor elements QA are not all oriented in the same direction, and the longitudinal direction of the plurality of semiconductor elements QA arranged on the outlet surface side (back side) is arranged perpendicular to the inflow direction of the cooling air. The longitudinal direction of the plurality of semiconductor elements QA arranged on the inlet surface side (the front side) is arranged in parallel along the inflow direction of the cooling air.

FIG. 11 is a diagram illustrating the temperature distribution of the base portion 100 of the heat sink 50 according to another embodiment.

Referring to FIG. 11, the temperature elevation is shown in gray scale. The black part indicates the case where the temperature is high, and the white part indicates the case where the temperature is low.

It can be seen that the white temperature region is wider in another embodiment than in the temperature distribution of the comparative example in FIG. 8, and the cooling effect is clearly higher.

Therefore, by configuring the heat sink 70, it is possible to perform cooling more efficiently than in the comparative example. Therefore, the heat dissipation capability of the heat sink can be fully utilized, and the size of the heat sink itself can be reduced.

When the heat sink 60 in FIG. 4 and the heat sink 70 in FIG. 10 are compared, the heat sink 60 has a higher cooling effect.

In the above description, as an example, the semiconductor elements QA1 to QA4 constituting the converter CNV are arranged on the inlet face side (front side), and the inverter INV is arranged on the outlet face side (back side). Although the configuration in which the semiconductor elements QA#1 to QA#4 are arranged has been described, the present invention is not limited to this. , semiconductor elements QA1 to QA4 forming the converter CNV may be arranged on the outflow surface side (rear side).

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

1 uninterruptible power supply, 2 AC input power supply, 3 bypass input power supply, 4 load, 5, 15, 17 contactor, 7, 9, 12 reactor, 8, 10 capacitor, 11 electrolytic capacitor, 14 switch, 18 thyristor switch, 30 Control device, 31 storage battery, 50-70 heat sink, 100 base part, 200 fin part.

Claims (4)

a plurality of first and second semiconductor modules including semiconductor devices for power conversion;
a heat sink for cooling the plurality of first and second semiconductor modules;
The heat sink
a base for mounting the plurality of first and second semiconductor modules;
a fin portion coupled to the base portion;
The plurality of first and second semiconductor modules are provided on the cooling air inlet surface side and the cooling air outlet surface side of the fin portion, respectively;
The longitudinal direction of the plurality of first semiconductor modules is provided so as to be perpendicular to the inflow direction of the cooling air from the inlet surface side of the fin portion to the outlet surface side,
The uninterruptible power supply is provided such that the longitudinal direction of the plurality of second semiconductor modules is parallel to the inflow direction of the cooling air of the fin portion. the plurality of first semiconductor modules are converters that convert AC voltage to DC voltage;
2. The uninterruptible power supply according to claim 1, wherein said plurality of second semiconductor modules are inverters for converting said DC voltage into AC voltage. 2. The uninterruptible power supply according to claim 1, wherein each of said plurality of first and second semiconductor modules includes one IGBT element. The plurality of first semiconductor modules are provided on a cooling air inlet surface side of the fin portion,
2. The uninterruptible power supply according to claim 1, wherein said plurality of second semiconductor modules are provided on a cooling air outlet surface side of said fin portion.

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