JP3799352B2 - Power converter - Google Patents

Description

  The present invention relates to a power conversion device that houses a plurality of sets of power conversion circuits.

  There are various types of power conversion circuits composed of semiconductor elements, including an inverter circuit that converts direct current into alternating current and a converter circuit that converts alternating current into direct current. The inverter circuit includes a variable voltage variable frequency inverter (hereinafter referred to as a VVVF inverter) circuit that variably controls the voltage and frequency of the AC output, and a constant voltage constant frequency inverter that controls the voltage and frequency of the AC output to be constant. There are circuits, etc. (hereinafter referred to as CVCF inverters), and these constitute a power conversion system.

  Taking a railway vehicle system as an example, a power conversion device in which a plurality of groups of VVVF inverter circuits for controlling an induction motor for driving a vehicle are housed for each control unit is attached to the vehicle. For example, a power converter that accommodates one vehicle, that is, four groups of VVVF inverter circuits that individually control one induction motor is widely used. This power conversion device is a system with excellent redundancy that operation can be continued by disconnecting the failed VVVF inverter circuit in the event of a failure. In addition, a CVCF inverter circuit is used in the auxiliary power supply system. Recently, a plurality of groups of VVVF inverter circuits and CVCF inverter circuits are housed in one power converter, and if the CVCF inverter circuit fails, the VVVF inverter circuit is used. In some systems, a group of circuits is switched to a CVCF inverter circuit to improve redundancy as a railway vehicle system.

  In an AC electric vehicle, a system that drives an induction motor by controlling an output voltage and an output frequency by combining a converter circuit that converts AC to DC and an inverter circuit that converts DC to AC is generally used. Yes. Conventionally, these various power conversion systems have been installed in vehicles as separate devices. Recently, however, the installation space has been reduced and the devices have been consolidated to reduce the number of wires connecting between the devices. There is a tendency to store various conversion circuits in one power conversion device. In a power conversion device in which a plurality of groups of power conversion circuits are housed in one device, for example, for each electrical function such as a converter conversion circuit unit, an inverter conversion circuit unit, a control board unit, and a control power supply unit, In many cases, each is mounted in a region partitioned inside and is configured as a unit.

  In a conversion circuit unit using a semiconductor element, a cooler is required for discharging heat generated by the semiconductor element (hereinafter referred to as loss heat) to the outside of the apparatus and using the temperature of the semiconductor element below an allowable value. The basic configuration of the cooler consists of a heat receiving part to which a semiconductor element is attached and a heat radiating part that dissipates heat to the outside air. The heat receiving part is placed in a sealed chamber part of the power converter, and the heat radiating part is an open room that communicates with the outside air. Placed in the part. The open room part where the heat radiating part is placed protrudes slightly from the housing of the device to make it easy to dissipate heat to the outside air, or it is used as a cooling wind tunnel for forcing cooling air by an electric blower, or it is installed under the floor of a railway vehicle In the apparatus, it is provided in a portion where it is easy to receive a traveling wind relatively flowing on the outer surface of the apparatus when the vehicle is traveling.

  A conventional power conversion apparatus that houses a plurality of groups of conversion circuits as described above will be described below. FIG. 11 is a circuit diagram of a power conversion device for driving a railway vehicle. FIG. 11 is a circuit diagram of a power conversion device that houses one group of motors, that is, four groups of VVVF inverter circuits that individually control four induction motors. is there. In the figure, a pantograph 1 is connected to a positive input terminal of a VVVF inverter circuit 4 via a circuit breaker 2 and a filter reactor 3, and a negative input terminal thereof is grounded through a wheel. A filter capacitor 5 is connected between the positive and negative input terminals of the VVVF inverter circuit 4, and an induction motor 6 is connected to the output terminal. In this way, the four groups of circuits are connected in parallel, and the four groups of VVVF inverter circuits 4 individually control the four induction motors 6 for one car. Among the electrical components shown in this circuit diagram, four groups of VVVF inverter circuits 4 and filter capacitors 5 are housed in one box to constitute a power conversion device 7A, and the other electrical components are each independently or other It is housed in a box of the apparatus, and these are electrically connected by vehicle body wiring to constitute a railway vehicle drive system.

  12A is a perspective view showing a state in which the above-described power conversion device 7A is mounted under the floor of the railway vehicle, and FIG. 12B is a side view seen from the traveling direction of the vehicle, and FIG. ) Is a plan view of the power conversion device 7A viewed from the direction of attachment to the bottom surface of the vehicle, and FIG. 13B is a bottom view thereof. In each of these drawings, the power conversion device 7A includes four coolers 9 for cooling a semiconductor element (for example, a collective term for a IGBT in which a snubber diode is connected in parallel). A single cooler 9 collectively stores a group of semiconductor elements 8 of the VVVF inverter circuit, and a filter capacitor 5 is stored in a single box (see, for example, Patent Document 1).

  In addition, although one group of VVVF inverter circuits is a three-phase inverter circuit of U, V, and W, depending on the case, one phase of each of the four groups of VVVF inverter circuits is attached to one cooler 9, Three of these may be arranged side by side. This is because, if the semiconductor elements 8 for each phase constituting the VVVF inverter circuit of each group are collectively arranged, the peripheral components can be easily arranged and electrically connected, and the power converter 7A is functionally divided. As a result, a unit configuration for each function is possible, and thus the cooler 9 is also formed by such a group of conversion circuits.

  11 to 13 is mounted with a cooling unit including a heat receiving portion to which the semiconductor element 8 is attached and a heat radiating portion that dissipates heat to the outside air. The heat receiving portion is sealed by the power converter 7A. It is placed in the chamber part, and the heat radiating part is placed in the open chamber part communicating with the outside air. The open room where the heat dissipating part is placed is slightly protruded from the housing, making it easy to dissipate heat to the outside air. .

  During operation of the power converter 7A, heat loss is generated from the semiconductor element 8, but this is transferred to the heat receiving part of the cooling unit mounted in the cooler 9 by heat conduction, and is dissipated from the heat radiating part of the cooling unit to the outside air. The semiconductor element 8 is cooled and can be used at an allowable temperature or lower.

  By the way, during the operation in which the four groups of VVVF inverters constituting the power converter 7A are all healthy, the four groups of VVVF inverters are individually controlled, but the heat loss generated from each group is the same. Yes, each of the coolers 9 dissipates almost the same amount of heat loss. However, at the time of failure of the power conversion device 7A, the group of VVVF inverter circuits that failed was disconnected by the circuit breaker 2, and the system was made redundant so that the operation could be continued with the remaining groups of VVVF inverter circuits. This is a feature of the power conversion device 7A.

  When the operation of the remaining three groups of VVVF inverter circuits is continued due to failure of the first group of VVVF inverter circuits, the semiconductor elements 8 constituting the VVVF inverter circuit that continues the operation include all the VVVF inverter circuits of the four groups. It is necessary to pass a larger current than when healthy. For this reason, the heat loss generated from the semiconductor element 8 is larger than that in a healthy state, and the heat dissipation capability of the cooler 9 is required to be higher than that in a healthy state. Accordingly, each of the coolers 9 can dissipate not only heat loss when all the four groups of VVVF inverter circuits are operating soundly but also heat loss due to failure that is increasing compared to the normal state. It is necessary to secure capacity. In other words, each cooler 9 has a sufficient cooling capacity at the time of soundness, and at the time of failure, the cooler 9 to which the semiconductor element 8 of the VVVF inverter circuit separated by the failure is attached does not perform the heat dissipation process at all. Only the cooler 9 to which the semiconductor element 8 of the remaining VVVF inverter circuit that continues the above is subjected to the heat dissipation process.

  As a result, the coolers 9 must be individually increased in size, which has been a factor that hinders the reduction in size and weight of the power conversion device 7A.

  Another conventional power conversion device that houses a plurality of groups of power conversion circuits will be described below. FIG. 14 is a circuit diagram of a power conversion device 7B in which a group of VVVF inverter circuits for driving a vehicle and a group of vehicle power CVCF inverter circuits 17 are configured as the same system. Elements are denoted by the same reference numerals and description thereof is omitted. Here, one of the two groups of VVVF inverter circuits is configured to be able to be operated by switching from the VVVF inverter circuit to the CVCF inverter circuit when the CVCF inverter circuit fails, and by securing the vehicle power supply, The system has increased redundancy.

  15A is a perspective view showing a state in which the power conversion device shown in FIG. 14 is mounted under the floor of the railway vehicle, and FIG. 14B is a side view seen from the traveling direction of the vehicle. 16 (a) is a plan view of the power conversion device 7 as viewed from the direction attached to the bottom surface of the vehicle, and FIG. 16 (b) is a bottom view thereof. This is provided with two coolers 9 for the VVVF inverter circuit and one cooler 9 for the CVCF inverter circuit, as in the conventional apparatus shown in FIGS. (For example, see Patent Document 2).

  Here, although details of the switching operation are omitted, when the CVCF inverter circuit fails, the cooler 9 to which the semiconductor element 8 of the CVCF inverter circuit is attached does not, of course, perform the heat dissipation process, and originally the VVVF inverter circuit. The two coolers that have been subjected to the heat dissipation treatment will work for the VVVF inverter circuit and the CVCF inverter circuit. As in the conventional device shown in FIGS. 11 to 13, the cooler 9 to which the semiconductor element 8 of the group that continues to operate as a VVVF inverter circuit is required to have a high heat dissipation capability compared to the normal state. It is necessary to make the outer shape of the cooler 9 suitable for the heat dissipation capability. Further, although it is required that the VVVF inverter circuit and the CVCF inverter circuit are configured in common, the heat loss generated from the semiconductor element 8 is not necessarily equal between the VVVF inverter circuit and the CVCF inverter circuit depending on the applied vehicle system. Nevertheless, since the coolers 9 having the same shape are used, it is difficult to say that each cooler 9 is equally responsible for heat dissipation even during sound operation. 7B was a factor that hindered the small size and weight reduction.

  Furthermore, another conventional power conversion device that houses a plurality of groups of conversion circuits will be described below with reference to FIGS. FIG. 17 is a circuit diagram of the power conversion device 7C, and substantially two sets of converter circuits 18 that convert the alternating current into direct current using alternating current as input, and the direct current converted by the converter circuit 18 with variable voltage, The inverter circuit 19 is configured to convert the variable frequency-controlled alternating current into an alternating current circuit, thereby forming a system for driving the four induction motors 6 of the railway vehicle. 18A is a plan view seen from the side where the power converter 7C is mounted on the bottom of the vehicle, FIG. 18B is a side view seen from the traveling direction of the vehicle, and FIG. 19 is FIG. It is AA arrow sectional drawing. The power conversion device 7C includes two cooling units 9a and 9b. Of these, the cooling unit 9a includes a semiconductor element 8 constituting a converter circuit, and the cooling unit 9b includes a semiconductor element 8 constituting an inverter circuit. It is attached and is configured to perform heat dissipation by being forcedly blown by the electric blower 14 (see, for example, Patent Document 3).

The heat loss generated from each conversion circuit does not increase or decrease at the same timing, but increases or decreases at different timings. When the railway vehicle is relatively low speed, that is, when accelerating or decelerating, the heat loss generated from the inverter circuit is large, and when operating at a relatively high speed, the heat loss generated from the converter circuit is large. Therefore, when the heat dissipation from the cooling unit 9a is large, the heat dissipation from the cooling unit 9b is relatively small, and when the heat dissipation from the cooling unit 9b is large, the heat dissipation from the cooling unit 9a is relatively small. It will be small. In addition, in this apparatus, since the heat radiation side of the cooling units 9a and 9b is cooled by forced air blowing, the thermal time constant is small, so the size of each cooling unit 9a and 9b is determined by the maximum heat loss. End up. That is, since the temperature of the cooler follows in a short time according to the increase / decrease of the heat loss, when the heat loss changes according to the time, it is necessary to enable cooling with the maximum heat loss in a short time.
JP-A-10-66201 JP 2000-134701 A JP-A-9-118225

  In the power converters shown in FIGS. 17 to 19, as in the power converters shown in FIGS. 11 to 13 or FIGS. In many cases, the heat load applied to the cooler is in an unbalanced state, and as a result, the cooler becomes large and obstructs the miniaturization and weight reduction of the device.

  An object of the present invention is to solve the above-described problem, and a cooling structure having a minimum necessary size can be realized by leveling the share of heat loss applied to a plurality of coolers. In addition, an object of the present invention is to provide a power conversion device that can be reduced in size and weight.

The invention according to claim 1 is a power converter that houses two groups of inverter circuits that are connected in parallel and can be operated independently of each other. It attached to the common cooling unit which has a part and a thermal radiation part, It is characterized by the above-mentioned.

The invention according to claim 2 includes two groups of inverter circuits that perform variable voltage and variable frequency control and inverter circuits that perform constant voltage and constant frequency control , which are connected in parallel and are independently operated individually. In a power conversion apparatus that houses a group of inverter circuits, the semiconductor elements constituting the two groups of inverter circuits are attached to one common cooling unit having a heat receiving portion and a heat radiating portion.

Invention, in the power converter according to claim 1 or 2, the semiconductor elements constituting one phase one inverter circuit on one surface of the cooler heat receiving unit, the same cooler heat according to claim 3 A semiconductor element constituting one phase of the other inverter circuit is attached to the other surface of the part.

Invention, in the power converter according to claim 1 or 2, wherein the condenser to the heat receiving portion and one of the inverter circuit one phase of the semiconductor element other inverter circuit one phase of the semiconductor device according to claim 4 Are installed side by side.

  Since the present invention is configured as described above, the sharing of loss heat applied to a plurality of coolers is leveled, thereby enabling a cooling structure with a minimum required size, The power converter device which can implement | achieve weight reduction can be provided.

  Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the drawings.

  FIG. 1 shows the configuration of a first embodiment of a power conversion device according to the present invention, in which (a) is a plan view seen from the direction attached to the bottom of a vehicle, and (b) is a bottom view thereof. It is. The power conversion device 7D shown here is applied to the four groups of VVVF inverter circuits whose circuit diagram is shown in FIG. 11 as a conventional device, and the components of each group include three coolers 9U, 9V, 9W. Each phase is divided and stored. That is, among the four groups of VVVF inverter circuits, the U-phase semiconductor elements 8 of each group are accommodated in the cooler 9U, the V-phase semiconductor elements 8 of each group are accommodated in the cooler 9V, and the W-phase of each group. The semiconductor element 8 is accommodated in the cooler 9W. The power conversion device 7D further accommodates four control units 15 and is configured to individually control four groups of VVVF inverter circuits.

  Here, in a state where the four groups of VVVF inverter circuits are operating soundly, the heat loss generated from the semiconductor element 8 is released to the outside air by the coolers 9U, 9V, 9W, and all the semiconductor elements 8 are below the allowable temperature. To be cooled. At this time, each of the coolers 9U, 9V, and 9W is loaded with substantially the same amount of heat loss, and the semiconductor element 8 is cooled to an allowable temperature or less.

  On the other hand, when one group out of the four groups of VVVF inverter circuits has failed, when this group is separated from the system and operated, a larger current than normal is supplied to the remaining VVVF inverter circuits that continue operation. It is necessary to prevent system performance degradation. At this time, the heat loss of the semiconductor element 8 constituting the VVVF inverter circuit increases. However, all three coolers 9U, 9V, and 9W are loaded with heat loss almost evenly, and the coolers 9U, 9V, and 9W originally have the ability to cool the heat loss for four groups. Therefore, even if the heat loss for the three groups increases from the normal time, sufficient cooling is performed.

  Thus, not only during normal normal operation of all groups of VVVF inverter circuits, but also when one group of VVVF inverter circuits is disconnected due to a failure and operated with the remaining groups of VVVF inverter circuits, the entire plurality of coolers are efficient. Good cooling performance. In general, the ratio of the size of the cooler to the outer shape of the power converter is large, and according to the present invention, the cooling system efficiently cools down, so that the entire cooler can be downsized and the power can be reduced. The entire conversion device can be reduced in size and weight.

  FIG. 2 shows the configuration of a second embodiment of the power converter according to the present invention, in which (a) is a plan view seen from the direction attached to the bottom of the vehicle, and (b) is a bottom view thereof. . In the power converter 7E shown here, the semiconductor elements 8 respectively constituting the two groups of VVVF inverter circuits and the group of CVCF inverter circuits shown in the circuit diagram of FIG. 14 are separately housed for each phase. That is, out of the three coolers 9U, 9V, and 9W, the cooler 9U includes two U-phase semiconductor elements 8 of the VVVF inverter circuit and one U-phase semiconductor element 8 of the CVCF inverter circuit. In the cooler 9V, two V-phase semiconductor elements 8 of the VVVF inverter circuit and one V-phase semiconductor element 8 in the CVCF inverter circuit are accommodated, and in the cooler 9W, the VVVF inverter The semiconductor elements 8 for two groups of the W phase of the circuit and the semiconductor elements 8 for one group of the W phase of the CVCF inverter circuit are housed. This power conversion device 7E also includes three control units 15, each configured to control two groups of VVVF inverter circuits and one group of CVCF inverter circuits.

  Here, when all of the circuits of the second group of VVVF inverter circuits and the first group of CVCF inverter circuits are in a healthy state, each of the coolers 9U, 9V, 9W is loaded with substantially the same amount of heat loss, and all the semiconductor elements Heat loss generated from the heat 8 is released to the outside air by the coolers 9U, 9V, and 9W, and the semiconductor element 8 is cooled to an allowable temperature or lower.

  On the other hand, when the CVCF inverter circuit fails, a group of VVVF inverter circuits is switched to the CVCF inverter circuit. At this time, it is necessary to supply a larger current to the remaining one group of VVVF inverter circuits that continue to operate so as to prevent the system performance from being deteriorated. Therefore, it is necessary to prevent the system performance from deteriorating by flowing a larger current than usual in the remaining VVVF inverter circuit for continuing the operation. As a result, the heat loss generated from one semiconductor element 8 is all greater than during healthy operation. However, all three coolers 9U, 9V, and 9W are loaded with heat loss almost evenly, and the coolers 9U, 9V, and 9W originally have heat loss from the VVVF inverter circuit for two groups and one group. The CVCF inverter circuit is provided with the ability to dissipate the heat loss of each semiconductor element 8, so that even if the heat loss for one group that continues operation increases more than usual, sufficient cooling is performed.

  Thus, according to the second embodiment, even when a group of CVCF inverter circuits fails, all the coolers function to dissipate the heat loss of the semiconductor elements, and the cooling system is efficient and efficient. A simple cooling system can be realized. As a result, the entire cooler can be reduced in size, and the entire power converter can be reduced in size and weight.

  FIG. 3 shows the configuration of a third embodiment of the power conversion apparatus according to the present invention, in which (a) is a plan view seen from the direction of being attached to the bottom of the vehicle, and (b) is the progression of the vehicle. It is the side view seen from the direction. The power conversion device 7F shown here is applied to the device shown in the circuit diagram of FIG. 17 as a conventional device. In the figure, the same elements as in FIG. To do. Here, the power conversion device 7 </ b> F includes a cooling unit 9 c attached to the blowing path of the electric blower 14. On this cooling unit 9c, the semiconductor element 8 constituting the inverter circuit is housed for each phase of U, V, W and divided into three parts in the width direction of the blower path, and the semiconductor element 8 constituting the converter circuit is positively connected. It is divided into a side and a negative side, and is mounted in two in the width direction of the blower path behind the semiconductor element 8 constituting the inverter circuit when viewed from the electric blower 14.

  The operation of this embodiment will be described below. At low speed, that is, at acceleration / deceleration, heat loss is mainly generated from the semiconductor element 8 of the inverter circuit, and heat loss from the converter circuit is small. During high-speed operation, heat loss is mainly generated from the semiconductor element 8 of the converter circuit, and heat loss from the semiconductor element of the inverter circuit is small. As described above, the heat loss generated from the converter circuit and the heat loss generated from the inverter circuit increase or decrease at different timings without increasing or decreasing at the same timing. In the cooling unit, the converter circuit and the inverter circuit are equally divided and arranged in the width direction, and are arranged before and after the air blowing path, so that it is possible to process almost uniform heat loss in all speed ranges.

  In this way, by arranging the converter circuit and the inverter circuit that generate heat loss that varies depending on the speed range in the front-rear direction of the air flow path, the cooling unit is loaded with heat loss that is substantially uniform in each speed range. As a whole, the cooling performance is efficiently demonstrated, and an efficient cooling system without waste in the cooling system can be realized.

  Thus, according to the third embodiment, it is possible to reduce the size of the entire cooler and to reduce the size and weight of the entire power conversion device.

FIG. 4 shows a fourth embodiment of the power conversion device according to the present invention, in which each semiconductor element 8 of the four groups of inverter circuits 4 shown in FIG. 11 is attached to a common cooling unit. It is a top view which shows a detailed structure, (b) is the sectional drawing. In each of these drawings, the cooling unit 30 includes a heat receiving portion 31 having a flat surface and a heat radiating portion 32 made up of a number of heat radiating fins formed on the back surface. And the semiconductor element 8 which comprises 4 groups of inverter circuits on the surface of the heat receiving part 31 is mounted | worn with 2 rows 2 columns for every group. In addition, four heat pipes 33 are embedded in the heat receiving portion 31 in parallel at appropriate intervals so as to equalize the heat receiving portion 31.
Here, the heat pipe 33 embedded in the heat receiving part 31 of the cooling unit 30 has the effect of thermally leveling the entire heat receiving part 31, but as described in the first and second embodiments, Since the heat is also transported to the mounting portion of the semiconductor element that has been cut off and no loss heat is applied, the heat loss of the semiconductor element 8 that continues to operate is transported to the entire heat receiving section 31 to be cooled.

  Thus, the heat pipe 33 embedded in the heat receiving section 31 of the cooling unit 30 can equalize the temperature of the heat receiving section 31 not only during a sound operation but also during a failure, so that the cooling unit 30 as a whole can be divided into a plurality of inverters. The heat loss of the semiconductor element 8 of the circuit is dissipated, and an efficient cooling system without waste in the cooling system can be realized. As a result, the entire cooler can be reduced in size, and the entire power converter can be reduced in size and weight.

  FIG. 5 shows a fifth embodiment of the power converter according to the present invention, in which each semiconductor element 8 of the four groups of inverter circuits 4 shown in FIG. 11 is attached to a common cooling unit. It is a top view which shows a detailed structure, (b) is the sectional drawing. In each of these drawings, the cooling unit 40 has a flat-shaped box-shaped heat receiving portion 41 and a heat radiating portion in which a large number of cooling fins are continuously formed on one outer peripheral portion of the heat receiving portion 41 divided into approximately half. 42, and the semiconductor elements 8 constituting the four groups of inverter circuits are mounted in two rows and two columns for each group on the other half of the surface. In addition, a refrigerant 43 made of fluorinate or water is sealed inside the heat receiving portion 41.

  The cooler unit 40 is a boiling cooling type, and the temperature of the mounting surface of the semiconductor element 8 can be leveled efficiently by the refrigerant 43. As a result, the entire cooler can be reduced in size, and the entire power converter can be reduced in size and weight.

  FIG. 6 shows a sixth embodiment of the power conversion device according to the present invention, and is a configuration example of a cooling unit in which the semiconductor elements 8 constituting the four groups of inverter circuits shown in FIG. It is a top view which shows a detailed structure, (b) is the sectional drawing. In each of these drawings, the cooling unit 50 includes a box-shaped heat receiving portion 51 that is flat as a whole, and a heat radiating portion 52 in which a large number of cooling fins are continuously formed on one outer peripheral portion that divides the heat receiving portion 51 into approximately half. And six semiconductor elements 8 (corresponding to those constituting the two groups of inverters shown in FIG. 11) are mounted in two rows and three columns on the other half surface, and six on the back surface. The semiconductor elements 8 (corresponding to those constituting the two groups of inverters shown in FIG. 11) are mounted in the same manner as the surface. A refrigerant 53 is sealed inside the heat receiving portion 51.

  This cooling unit 50 is also a boiling cooling type, and the temperature of the mounting surface of the semiconductor element 8 can be leveled efficiently by the refrigerant 53. In this case, since the semiconductor elements 8 are dispersedly arranged on the front and back surfaces of the heat receiving portion 51, the cooling efficiency is further improved as compared with the cooling unit 40 shown in FIG. There is also an effect that the arrangement of the conductors connected to can be simplified.

  FIG. 7 shows a seventh embodiment of the power conversion device according to the present invention, in which each semiconductor element 8 of the four groups of inverter circuits 4 shown in FIG. 11 is attached to a common cooling unit. Is a plan view showing a detailed configuration, and (b) is a cross-sectional view thereof. In each of these drawings, the cooling unit 60 includes a box-shaped heat receiving portion 61 that is flat as a whole, and a heat radiating portion in which a large number of cooling fins are continuously formed on one outer peripheral portion obtained by dividing the heat receiving portion 61 into approximately half. 62, and the semiconductor elements 8a and 8b of the respective phases are mounted in two rows and six columns in the width direction of the heat receiving portion 61, that is, for each phase, on the remaining half of the surface. A refrigerant 63 is sealed inside the heat receiving portion 61.

  This embodiment corresponds to the fact that, among the four groups of inverter circuits shown in FIG. 11, the two groups of inverter circuits and the remaining inverter circuits use semiconductor elements of different types or ratings. The semiconductor elements 8a of the inverter circuit are arranged at intervals in the order of U phase, V phase, and W phase, and the semiconductor elements 8b of the other two groups of inverter circuits are U phase, V phase, and W phase. Are arranged adjacent to the semiconductor element 8a in this order.

  Also in this cooling unit 60, the temperature of the heat receiving portion 61 at the time of failure is leveled without being partially biased, and a cooling system more efficient than the cooler shown in FIG. 5 or FIG. 6 can be realized.

  FIG. 8 shows an eighth embodiment of the power converter according to the present invention, in which each semiconductor element 8 of the four groups of inverter circuits 4 shown in FIG. 11 is attached to a common cooling unit. Is a plan view showing a detailed configuration, and (b) is a side view thereof. In each of these drawings, the cooling unit 70 has a flat-shaped box-shaped heat receiving portion 71 and a heat radiating portion in which a number of cooling fins are continuously formed on one outer peripheral portion obtained by dividing the heat receiving portion 71 into approximately half. 72, and the semiconductor elements 8a and 8b of the respective phases described above are arranged in 2 rows and 6 columns in the lateral width direction of the heat receiving portion 61 on the remaining half of the surface. A refrigerant 63 is sealed inside the heat receiving portion 61.

  In the cooling unit 70 shown here, the mounting surface of the semiconductor element 8a is replaced by the mounting surface of the semiconductor element 8b by the height difference ΔH in order to align the height positions when the heights of the electrical connection terminals of the semiconductor elements are different. Irregularities are formed on the surface of the heat receiving portion 71 so as to be lower. As a result, the heights of the electrical connection terminals of the semiconductor elements 8a and 8b are made uniform and can be connected as they are by the straight connection conductors 21, and the electrical connection between the semiconductor elements becomes easy and the configuration is simplified. The effect of being done is also obtained.

  FIG. 9 shows a ninth embodiment of the power conversion apparatus according to the present invention, and particularly shows a modification of the cooling unit constituting the third embodiment shown in FIG. (A) is a top view which shows the detailed structure of a cooling unit and the attachment state of a semiconductor element, and (b) is the side view. Here, the cooling unit 80 includes a flat heat receiving portion 81. The heat receiving portion 81 may have a heat pipe embedded therein, or may have a structure that is formed in a box shape and seals the refrigerant therein. A semiconductor element 8a constituting an inverter and a semiconductor element 8b constituting a converter are mounted on the surface of the heat receiving portion 81, and heat radiation is made by arranging a large number of cooling fins in parallel on the back surface of the heat receiving portion 81 in the wind flow direction. A portion 82 is formed.

  The semiconductor element 8a attached to the surface of the heat receiving portion 81 of the cooling unit 80 includes three sets of semiconductor elements U1, U2, U3 for the U phase constituting three groups of inverter circuits and three sets of semiconductors for the V phase. The elements V1, V2, V3 and three sets of semiconductor elements W1, W2, W3 for the W phase are included, and the semiconductor element 8b includes three sets of semiconductor elements Q1, Q2, Q3 constituting three groups of converter circuits. It is out.

  These semiconductor elements are seen in the direction in which the wind passes through the heat radiating portion 82, the semiconductor elements U 1, U 2, U 3 for the U phase of the inverter circuit, the semiconductor elements V 1, V 2, V 3 for the V phase, and the W phase component. The semiconductor elements W1, W2, and W3 are sequentially arranged in a row, and the semiconductor elements Q1, Q2, and Q3 of the converter circuit are arranged in a row on the side thereof. The feature of this embodiment is that the U-phase semiconductor elements are arranged in the order of U1, U2 and U3 in the wind flow direction, whereas the V-phase semiconductor elements are arranged in the order of V3, V1 and V2. The semiconductor elements for the W phase are arranged in the order of W2, W3 and W1.

  As is well known, the temperature of the cooling air gradually rises due to the heat loss of the semiconductor elements while the cooling air passes between the cooling fins 82 of the cooling unit 80. Therefore, the cooling efficiency of the semiconductor element arranged upstream is high, and the cooling efficiency of the semiconductor element arranged downstream is low. Therefore, as described above, the temperature of the semiconductor elements can be leveled for each group of inverters by changing the position of the semiconductor elements in each group of the inverters regularly in the cooling air passage direction. An efficient cooling system can be realized.

  In addition, when a group of inverters is separated and operated due to a failure, the heat loss from the semiconductor elements of this inverter circuit is eliminated and the heat loss of the semiconductor elements of the remaining inverters increases, but there is a margin in the cooling capacity. Therefore, it is possible to configure a system with excellent redundancy at the time of failure.

  FIG. 10 shows a tenth embodiment of the power conversion device according to the present invention, in which an electric blower is disposed in an open chamber portion disposed adjacent to the sealed chamber portion, and two sets of cooling units and the related units are related thereto. In this configuration, two sets of peripheral circuits are arranged side by side in the wind flow direction, (a) shows a plan view thereof, and (b) shows a side view thereof. In each of these drawings, two sets of cooling units 90a and 90b have the same shape as the cooling unit shown in FIG. 4, and six semiconductor elements 8a are mounted on the surface of the heat receiving portion of the cooling unit 90a. Six semiconductor elements 8b are mounted on the surface of the heat receiving portion 90b. These cooling units 90a and 90b are mounted such that the semiconductor elements 8a and 8b are housed on the sealed chamber portion 12 side, and a heat radiating portion made of cooling fins is located on the open chamber portion 13 side. In this case, the cooling units 90 a and 90 b are arranged side by side in a direction orthogonal to the direction in which the wind is sent by the electric blower 14. On the other hand, the peripheral circuit 22a related to the semiconductor element 8a attached to the cooling unit 90a is attached to the open chamber portion on the downstream side of the cooling unit 90b when viewed in the direction of the air flow, and conversely, attached to the cooling unit 90b. A peripheral circuit 22b related to the semiconductor element 8b is mounted in an open chamber portion on the downstream side of the cooling unit 90a when viewed in the direction of air flow. That is, the cooling unit and the peripheral circuit related to each other are mounted with their positions interchanged.

  Thus, by arranging the peripheral circuits 22a and 22b downstream of each other group, a plurality of groups of conversion circuits are made common to the flow of the cooling air, and the temperature rise of the cooling air is leveled. Similarly to the ninth embodiment shown in FIG. 9, when a group is separated due to a failure, the heat loss of the cooling units 90b and 90a to which the upstream side semiconductor elements 8a and 8b are attached as the peripheral circuits 22a and 22b. With the remaining groups operating, there is a sufficient cooling capacity even if the amount of heat generated increases, so that a system with excellent redundancy at the time of failure can be configured.

The top view and the bottom view which looked at the 1st example of the power converter concerning the present invention from the direction attached to the bottom of vehicles. The top view and the bottom view which looked at the 2nd example of the power converter concerning the present invention from the direction attached to the bottom of vehicles. The top view and the side view which looked at 3rd Example of the power converter device which concerns on this invention from the direction attached to the bottom face of a vehicle. The top view which shows the attachment state of the cooling unit which comprises 4th Example of the power converter device which concerns on this invention, and a semiconductor element, and its sectional drawing. The top view which shows the attachment state of the cooling unit which comprises 5th Example of the power converter device which concerns on this invention, and a semiconductor element, and its sectional drawing. The top view which shows the attachment state of the cooling unit which comprises 6th Example of the power converter device which concerns on this invention, and a semiconductor element, and its sectional drawing. The top view which shows the attachment state of the cooling unit which comprises 7th Example of the power converter device which concerns on this invention, and a semiconductor element, and its sectional drawing. The top view and its side view which show the attachment state of the cooling unit which comprises the 8th Example of the power converter device which concerns on this invention, and a semiconductor element. The top view which shows the attachment state of the cooling unit and semiconductor element which comprise 9th Example of the power converter device which concerns on this invention, and its side view. The top view which shows the attachment state of the cooling unit and semiconductor element which comprise 10th Example of the power converter device which concerns on this invention, and its side view. The circuit diagram which shows the structure of the power converter device for a rail vehicle drive which has a 4 group VVVF inverter circuit as a conventional power converter device. The perspective view which shows the state which mounted | worn the power converter device shown in FIG. 11 under the floor of a railway vehicle, and the side view seen from the advancing direction of the vehicle. The top view which looked at the power converter device shown in FIG. 11 from the direction attached to the bottom face of a vehicle, and its bottom view. The circuit diagram which shows the structure of the power converter device for a railway vehicle drive containing 2 groups of VVVF inverter circuits and 1 group of CVCF inverter circuits as another conventional power converter device. The perspective view which shows the state which mounted | wore the underfloor of the rail vehicle with the power converter device shown in FIG. 14, and the side view seen from the advancing direction of the vehicle. The top view which looked at the power converter device shown in FIG. 14 from the direction attached to the bottom face of a vehicle, and its bottom view. The circuit diagram of the power converter device for a vehicle drive which accommodated the multiple groups conversion circuit as another conventional power converter device. The top view seen from the side which mounts the power converter device shown in FIG. 17 in a vehicle bottom part, and the side view seen from the advancing direction of the vehicle. The longitudinal cross-sectional view of the power converter device shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pantograph 2 Circuit breaker 3 Filter reactor 4 VVVF inverter circuit 5 Filter capacitor 6 Induction motors 7A-7F Power converters 8, 8a, 8b Semiconductor elements 9, 9U, 9V, 9W Coolers 9a, 9b, 9c Cooling unit 12 Sealed chamber Part 13 Opening room part 14 Electric blower 15 Control unit 17 CVCF inverter circuit 18 Converter circuit 19 Inverter circuit 21 Connection conductors 22a and 22b Peripheral circuits 30, 40, 50, 60, 70, 80, 90a, 90b Cooling units 31, 41, 51, 61, 71, 81 Heat receiving part 32, 42, 52, 62, 72, 82 Heat radiating part 33 Heat pipe
43, 53, 63 Refrigerant

Claims (4)

In a power conversion device that houses two groups of inverter circuits that are connected in parallel and can be operated independently of each other ,
A power conversion device, wherein the semiconductor elements constituting the two groups of inverter circuits are attached to one common cooling unit having a heat receiving portion and a heat radiating portion. In a power converter that houses two groups of inverter circuits, an inverter circuit that performs variable voltage variable frequency control and an inverter circuit that performs constant voltage constant frequency control , which are connected in parallel and each independently operated ,
A power conversion device, wherein the semiconductor elements constituting the two groups of inverter circuits are attached to one common cooling unit having a heat receiving portion and a heat radiating portion.   A semiconductor element constituting one phase of one inverter circuit is attached to one surface of the cooler heat receiving portion, and a semiconductor element constituting one phase of another inverter circuit is attached to the other surface of the same heat receiving portion. The power converter according to claim 1 or 2, wherein   The power converter according to claim 1 or 2, wherein a semiconductor element for one phase of one inverter circuit and a semiconductor element for one phase of another inverter circuit are mounted side by side on the cooler heat receiving portion.

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