JP6319074B2 - Power converter - Google Patents

Description

  The present invention relates to a power conversion device that includes a box body that houses components of a power conversion device such as an inverter device, and that cools internal component devices by passing air through the box.

  In general, a power conversion device such as an inverter is mainly composed of a semiconductor rectifier element constituting a rectifier circuit, a semiconductor switch element constituting an inverter circuit, and a smoothing capacitor provided between an output part of the rectifier circuit and an input part of the inverter circuit. A circuit component device, a control circuit of an inverter circuit, and the like are accommodated in a box.

  In particular, main circuit components such as semiconductor elements and capacitors that generate a large amount of heat need to be cooled in order to suppress temperature rise. For this reason, it is general to cool the component equipment contained inside the box body by forcing the cooling air through the box body so that the cooling air sucked from one end of the box body is exhausted from the other end of the box body. Done.

  A power conversion device that performs cooling with cooling air in this manner is well known as shown in, for example, Patent Document 1. FIG. 8 shows a conventional example of such a power converter.

  In FIG. 8, 50 is a rectangular parallelepiped box which constitutes the main body of the power converter. An intake port 52 is provided at one end of the box body 50, and an exhaust port 53 is provided at the opposite end. A cooling fan 54 composed of a suction fan is provided facing the exhaust port 53 of the box 50. Further, inside the box 50, a semiconductor rectifying element constituting a power conversion device, a semiconductor module element 61 in which a semiconductor switch element is modularized, and a cooling body 62 with a radiation fin coupled to the semiconductor module element 61 are provided. Components such as a capacitor 63 for smoothing a DC voltage, a control circuit 64 for controlling on / off of the semiconductor module element 61, and a terminal block 65 for drawing and connecting main circuit conductors and control lines are accommodated. The semiconductor module element 61 and the capacitor 63 are connected via a main circuit connection conductor 66. Although not shown here, each component device is fixed to the box 50 or an internal support frame via an appropriate support.

  In such a power converter, by driving the cooling fan 54, outside air is sucked into the box body 50 as cooling air from the intake port 52. The cooling air flows through the box and is exhausted from the exhaust port 53. Since the box 50 acts as one wind tunnel, the cooling air sucked into the box is guided to the inner wall of the box and flows toward the exhaust port 53. During this flow-through process, the cooling air comes into contact with the component devices housed therein to cool the component devices. Thus, the cooling air whose temperature has risen is exhausted from the exhaust port 53 to the outside by the cooling fan 54.

  Most of the dust contained in the outside air is removed by the filter and is sucked into the box. However, the cooling air drawn into the box contains a small amount of fine dust that has passed through the filter. For this reason, when the power conversion device is operated for a long period of time, in the process in which the cooling air sucked from the outside air flows through the box, fine dust contained therein adheres to and accumulates on the surface of each component device. If the dust adheres to the terminals of the component equipment where the dust is electrically exposed or the main circuit connecting conductor 66, the insulation is hindered, resulting in a short circuit accident and trouble in operation.

  For this reason, a dustproof filter is attached to the air inlet 52 of the box 50 to suppress the suction of dust. However, it is difficult to completely suppress the suction of dust. Therefore, this is dealt with by increasing the insulation distance of each component device. However, in this case, there is a problem that the power conversion device used at a particularly high voltage becomes large.

  Further, in this type of power conversion device, as shown in FIG. 9, the inside of the box 50 is divided into two compartments by a partition wall 55 made of a metal plate, and the components are separately accommodated. Cooling is performed indoors. That is, the cooling body 62 and the capacitor 63 coupled to the semiconductor module element 61 having a large calorific value are accommodated in one compartment 51a, and the remaining components, connection conductors 66, and the like are accommodated in the other compartment 51b. The compartments 51a and 51b are provided with intake ports 52a and 52b and exhaust ports 53a and 53b in communication with each other. Cooling fans 54a and 54b are provided opposite to the exhaust ports 53a and 53b, respectively.

  When the cooling fans 54a and 54b in each compartment are operated, the outside air sucked into the compartments 51a and 51b from the intake ports 52a and 52b flows through the compartments as cooling air and is discharged to the outside through the exhaust ports 53a and 53b. Is done. In this process, the cooling air comes into contact with the component devices accommodated in the respective compartments to cool the component devices.

  In this way, each compartment formed by partitioning the box body 50 with the partition wall 55 is partitioned small, so that the cooling air flows concentrated on the components accommodated in the respective compartments, so that the cooling effect is obtained. Can be increased.

  In such a conventional power conversion device, the partition wall 55 that partitions the inside of the box 50 is formed of a metal plate such as a steel plate. On the other hand, the capacitor 63 with the connection terminal exposed needs to secure an insulation distance between the connection terminal and the partition wall 55. Therefore, a part of the body of the capacitor 63 protrudes above the partition wall 55, and a part of the body of the capacitor is disposed outside the compartment 51a. However, this makes it difficult to uniformly cool the entire capacitor, necessitating the use of a capacitor having a large heat resistance capacity.

  The compartment 51b is also cooled by allowing the outside air sucked by the cooling fan 54b to flow inside. Therefore, during long-term operation, fine dust contained in the outside air adheres to and accumulates on the surfaces of the component devices accommodated therein. Since the main circuit conductor 66 connecting the semiconductor module element 61 and the capacitor 63 and the connection terminal of the capacitor 63 are electrically exposed, there is a high possibility that fine dust accumulates on these to cause an insulation failure. For this reason, it is necessary to ensure the sufficient insulation distance of a component apparatus for the compartment containing the main circuit conductor and terminal which are not insulated. As a result, there is a problem that the power converter becomes large.

JP 2005-348533 A

  The present invention solves the above-described problems in the conventional apparatus, and can uniformly cool the entire component equipment, particularly the capacitor, so that there is little adhesion and accumulation of dust on the exposed terminal portion and main circuit connecting conductor portion. An object of the present invention is to provide a power conversion device.

  In order to solve the above-described problems, the present invention provides a power conversion apparatus in which components are housed in a closed box, and a plurality of compartments are formed inside the box by partitioning it with partition walls. At least one of the compartments is configured to allow forced cooling air to flow from the outside, and a partition adjacent to the partition wall through the partition wall is configured not to allow forced cooling air to flow from the outside. A component device that requires cooling of the power conversion device is accommodated in a compartment where the cooling air can be forced to flow through, and an electrical connection terminal portion of the component device accommodated in the compartment is connected to the partition wall. And exposed in the compartment where the forced cooling air cannot be forced through, and between the exposed connection terminal portions of the constituent equipment in the compartment where the forced cooling air cannot flow through, and other constituent equipment Connection end And performing the electrical connection of the component devices mutually by connecting the connecting conductors between the parts.

  In the present invention, the partition wall is preferably composed of an insulating thin plate, and a flexible synthetic resin thin plate is suitable as the insulating thin plate.

  The partition wall composed of the synthetic resin thin plate having flexibility is fixed to the frame of the box by fitting the partition wall and a notch for fitting provided in a corresponding portion of the frame of the box. be able to.

  In addition, the component device includes a capacitor, and the partition wall is provided with a through-portion for exposing the electrical connection terminal portion of the capacitor to the compartment where the cooling air cannot be forced. And in this penetration part, the cut-and-raised part can be provided in the compartment side in which the forced flow of the said cooling air is impossible.

  Further, a partition chamber in which the cooling air can be forced through is formed above and below the box body, and a partition chamber in which the cooling air cannot be forced through is formed in the middle of the box, so that the cooling air can be forced through. The connecting terminal portions of the components housed in the separate compartments are exposed in the compartments where the cooling air cannot be forced through, adjacent to each other through the partition walls, and this cooling air cannot be forced through In the above configuration, the connection terminals may be connected to each other by a connection conductor to electrically connect the components housed in the compartment where the cooling air can be forced through.

  According to this invention, the component device that requires cooling of the power conversion device is accommodated in the compartment that is formed by partitioning the partition wall in the box and capable of forced throughflow of cooling air, and the electrical connection terminal of the component device is provided. The exposed connecting terminal of the component device is exposed through the partition wall and exposed through the partition wall to the adjacent compartment where the cooling air is not allowed to flow, and the cooling air cannot be forced through. The connection conductors are electrically connected to each other and to connection terminal portions of other components. By configuring in this way, the connection terminals and connection conductors of the component devices that are exposed are housed in a compartment where forced cooling air cannot be forced through, so that the accumulation of fine dust hardly occurs even after a long period of operation. Absent. Therefore, the insulation performance can be kept stable for a long time without securing an insulation distance more than necessary in the box. This contributes to downsizing of the device.

  In addition, since the partition wall is made of an insulating material, it is not necessary to consider the insulation distance from the contact terminal portion of the component device passing through the partition wall. Then, only the connection terminal portion may be provided in a compartment where forced cooling air cannot flow. Furthermore, since the entire body of the component equipment that requires cooling can be housed in a compartment where cooling air can be forced through, the cooling effect of the component equipment can be enhanced, and the component equipment can be downsized. Become.

BRIEF DESCRIPTION OF THE DRAWINGS Side surface sectional drawing which shows schematic structure of the 1st Example of the power converter device of this invention. The side view which shows the state which removed the side plate of 2nd Example of the power converter device of this invention. The perspective view which shows the external appearance of the state which removed the side plate of 2nd Example of the power converter device of this invention. Side surface sectional drawing which shows the structure of the 2nd Example of the power converter device of this invention. The fragmentary perspective view which expands and shows the coupling | bonding structure of the partition wall and box frame in 2nd Example of the power converter device of this invention. The fragmentary perspective view which expands and shows the terminal penetration part of the partition wall in 2nd Example of this invention. Side surface sectional drawing which shows the application example of 2nd Example of this invention. Side surface sectional drawing which shows the prior art example of a power converter device. Side surface sectional drawing which shows the other conventional example of a power converter device.

  Embodiments of the present invention will be described with reference to the embodiments shown in the drawings.

  FIG. 1 shows a schematic configuration of a first embodiment of the power conversion apparatus of the present invention.

  In FIG. 1, reference numeral 11 denotes a closed box constituting the main body of the power converter, which is usually formed of a steel plate. Two compartments 16 and 17 are formed in the box 11 by partitioning with a partition wall 15 made of an insulating thin plate made of synthetic resin, for example.

  The compartment 16 has an opening on the opposite end face, and is configured to allow forced flow of cooling air. That is, one of them is an intake port 12 for sucking outside air into the box body 11, and the other is an exhaust port 13 for exhausting air from the box body to the outside air. By attaching a cooling fan 14, which is a suction fan, facing the exhaust port 13, outside air is sucked as cooling air from the intake port 12. The cooling air is forced to flow through the interior of the compartment 16 and exhausted from the exhaust port 13. On the other hand, the partition chambers 17 adjacent via the partition wall 15 are configured such that the entire peripheral wall is closed and the forced flow of the cooling air is impossible.

  In the compartment 16 configured to forcibly flow cooling air, a cooling body 22 with a radiation fin to which a semiconductor module element 21 in which a semiconductor rectifying element or a semiconductor switching element having a large calorific value of the power converter is combined is combined. The capacitor 23 is accommodated. The connection terminal portion 21a of the semiconductor module element 21 is exposed in the adjacent compartment 17 through the through hole 15a provided in the partition wall. Similarly, the connection terminal portion 23 a of the capacitor 23 is exposed to the compartment 17 through the through hole 15 b provided in the partition wall 15.

  The connection terminal 21 a of the semiconductor module element 21 exposed to the compartment 17 and the connection terminal 23 a of the capacitor 23 are connected to each other by a connection conductor 26 in the compartment 17.

  In addition, the compartment 17 accommodates a control circuit 24 that performs on / off control of the semiconductor module element 21, a terminal block 25 that is used for internal and external electrical connections, and the like.

  When the power conversion device configured as described above is in operation, the cooling fan 14 is driven. As a result, outside air is sucked into the compartment 16 as cooling air from the air inlet 12 as indicated by an arrow. The cooling air flows through the compartment 16 and is discharged from the exhaust port 13 to the outside. For this reason, the cooling body 22 with which the capacitor | condenser 23 accommodated in the compartment 16 and the semiconductor module element 21 were couple | bonded is forcedly cooled by cooling air, and a temperature rise is suppressed.

  At this time, the compartment 17 is configured such that the cooling air is not forced to flow through, so that the outside air is not flowed through. For this reason, even if it is operated for a long time, the connection terminal portions 21a and 23a, the connection conductor 26, the control circuit 24 and the terminal block 25 of the semiconductor module element and the capacitor 23 accommodated in the compartment 17 are contained in the outside air. There is almost no adhesion of fine dust.

  Thereby, the connection terminal part 21a of the semiconductor module element 21, the terminal part 23a of the capacitor | condenser 23, and the connection conductor 26 which comprise the main circuit of a power converter device can maintain insulation performance stably for a long period of time.

  Next, a second embodiment of the power converter of the present invention shown in FIGS. 2 to 7 will be described.

  2 and 3 show a side view and a perspective view of the power converter of the present invention with the side plate removed, and FIG. 4 shows a side cross-sectional view.

  In the second embodiment, the interior of the box 30 constituting the main body is partitioned by a partition wall 35 and a partition wall 39 to form three compartments 36, 37, and 38. Here, at least the partition wall 35 is formed of an insulating synthetic resin thin plate having flexibility.

  The compartments 36 and 38 have openings 32a, 32b, 33a, 33b serving as intake ports or exhaust ports at both ends, and are configured to be able to forcibly flow cooling air from the outside. A compartment 37 formed between the compartments 36 and 38 is configured such that at least one end is closed and the cooling air cannot be forced through from the outside.

  Capacitor 43 and transformer 47, which are components that require cooling with a large amount of heat generation, are accommodated in compartment 36 configured to allow forced flow of cooling air. The connection terminal 43a of the capacitor 43 is exposed to a compartment 37 that is configured to pass through a through hole provided in the insulating partition wall 35 so that the forced flow of cooling air is impossible.

  The compartment 37 accommodates a connection terminal of a semiconductor module element 41 obtained by modularizing a semiconductor rectifier element or a semiconductor switch element coupled to a cooling body with cooling fins 42. The cooling body 42 coupled to the semiconductor module element 41 is accommodated in a compartment 38 that is configured to penetrate the partition wall 39 and to allow forced flow of cooling air.

  The semiconductor module element 41 and the capacitor 43 are electrically connected at their connection terminals in the compartment 37 by the main circuit connection conductor 46.

  An input terminal 51 for connecting to an AC power source and an output terminal 52 for connecting to a load are provided on the front wall of the box 30. The input terminal 51 is drawn into the compartment 37 by the connection conductor 53 through the protective switch 49 and is connected to the connection terminal 41 a that is an AC input terminal of the power conversion circuit of the semiconductor module element 41. The connection terminal 41 a serving as the output terminal of the power conversion circuit of the semiconductor module element 41 is connected to the output terminal 52 via the connection conductor 54.

  The compartment 37 further houses a bypass electromagnetic switch 48 for bypassing the output of the power converter by short-circuiting. The bypass electromagnetic switch 48 is connected in parallel to the connection terminal 41a of the semiconductor module element serving as the output terminal of the power conversion circuit via the connection conductor 56.

  All of the electrical connections of the main circuit are made in a compartment 37 that is configured so as not to allow forced flow of cooling air.

  2 to 4, reference numerals 31a and 31b denote a base frame and a support frame constituting the box body 30, respectively.

  In addition, the partition wall 35 which partitions off the compartments 36 and 37 can be made flexible by being composed of an insulating synthetic resin thin plate. The flexible partition wall 35 can be easily fixed to the box 5 without using a fixing screw.

  FIG. 5 shows a coupling structure between the partition wall 35 and the support frame 31b. A fitting notch 35c or a fitting projection 35d is provided at a location where the partition wall 35 is coupled to the support frame 31b. Then, a fitting notch 31c or a fitting hole 31d is provided at a corresponding portion of the support frame 31b. When the partition wall 35 is attached to the box, it is bent slightly to fit the fitting notch 35c into the fitting notch 31c of the support frame 31b, and the fitting projection 35d is fitted into the fitting hole 31d. Thereby, since the partition wall 35 is supported by the fitting notch 31c and the fitting hole 31d of the support frame 31b, it can be stably attached to the box 30.

  Furthermore, a through hole is provided for allowing the connection terminal 43a of the capacitor 43 provided in the partition wall 35 to pass therethrough. As shown in FIG. 6A, this through hole can be provided individually corresponding to each connection terminal 43a. Or as shown in FIG.6 (b), it can provide in the through-hole 35b common to the two connection terminals 43a and 43a of one capacitor | condenser. The common through hole 35b is cut and raised at both ends to facilitate positioning of the capacitor when passing through the connection terminal 43a of the capacitor 43. Further, if the height of the cut and raised 35e is set to the height of the connection terminal 43a of the capacitor, the cut and raised 35e can be pressed by the connection conductor 26, so that the partition wall 35 can be more stably fixed.

  The power conversion device 1 configured as described above is accommodated in a multistage manner as shown in FIG. 7 in a plurality of units for each of the three phases. For example, when the voltage rating of the power conversion device 1 is 1 kV, a voltage of 6 kV can be output when the output terminals of five power conversion devices 1 are connected in series with each other for each phase.

  The high-pressure board 10 is provided with an air inlet 10a covered with a filter 10b on the front side, and an air passage 10c common to the three power converters 1 on the back side. And the ceiling wall of the ventilation path 10c is opened, and the suction-type cooling fan 14 is provided here.

  By driving the cooling fan 14, outside air is sucked into the high-pressure panel 10 from the front air inlet 10 a through the filter 10 b. Most of the dust contained in the outside air that has been sucked in passes through the filter 10b. However, since the dust cannot be completely removed, a slight amount of fine dust remains in the outside air.

  The outside air slightly containing fine dust sucked into the high-pressure board 10 flows as cooling air through the power conversion device 1 and the ventilation path 10c as indicated by arrows.

  The compartments 36 and 38, which are provided above and below the box 30 of the power converter 1 and configured to allow forced flow of cooling air, communicate with the ventilation path 10c of the high-pressure board 10. Accordingly, the cooling air flows through the compartments 36 and 38 in each power conversion device 1 and forces the condensers 43, the transformers 47, and the cooling bodies 42 of the semiconductor module elements 41 with the components accommodated in the respective compartments. Cooling.

  However, since the components housed in the compartments 36 and 38 are insulated, no insulation failure occurs even if fine dust adheres to these surfaces.

  On the other hand, the intermediate compartment 37 in which the connection terminals of the component devices and the connection conductors 46, 53, 54, 56 connecting them are accommodated is closed at the rear end side so that the cooling air cannot flow therethrough. Yes. For this reason, the fine dust contained in the outside air hardly adheres to the connection conductor or the like accommodated in the compartment 37. As a result, the occurrence of insulation failure due to dust accumulation in the main circuit of the power converter 1 is suppressed. That is, the compartment 37 can maintain the electrical insulation performance without making the space larger than necessary by disabling the flow of the cooling air.

  As a result, the power conversion device according to the present invention can be stably operated for a long period of time without any insulation failure even if forced cooling is performed by passing cooling air that has taken in outside air.

  In addition, if a thin plate made of an insulating material such as an insulating synthetic resin thin plate is used for the partition wall constituting the compartment by partitioning the box constituting the main body, only the connection terminal at the tip of the capacitor is penetrated. The tip can be placed close to the partition wall. As a result, almost the entire condenser can be accommodated in the compartment 36 configured to allow the cooling air to flow therethrough. As a result, it is possible to uniformly cool the entire component device such as a capacitor in the compartment, and the cooling effect can be enhanced.

11: Box body 12: Inlet port 13: Exhaust port 14: Cooling fan 15: Insulating partition wall 16: Compartment chamber 17 in which cooling air can be forced through 17: Compartment chamber 21 in which cooling air cannot be forced through 21: Semiconductor module Element 21a: Connection terminal 22: Semiconductor module element cooling body 23: Capacitor 23a: Connection terminal 24: Control circuit 25: Terminal block 26: Connection conductor

Claims (4)

In the power conversion device in which components are housed in a closed box, a plurality of compartments are formed by partitioning the inside of the box by partition walls, and at least one of the compartments is external The cooling chamber is configured to allow forced flow of cooling air, and the adjacent compartment through the partition wall is configured not to allow forced cooling air to flow from the outside, and the cooling chamber is configured to allow forced flow of cooling air. In addition, a component device that requires cooling of the power conversion device is accommodated, and the electrical connection terminal portion of the component device accommodated in the compartment is not allowed to pass through the partition wall to forcibly pass the cooling air. Connected between the exposed connection terminal portions of the component devices and between the connection terminal portions of other component devices by connection conductors in the partition chamber where the cooling air cannot be forced through. To do Shall more for electrical connection of the construction component interconnect, further wherein the partition wall is constituted by an insulating thin plate, also contains capacitors in the configuration device, the partition wall, the electrical connection terminals of the capacitor A through portion is provided in the compartment where the cooling air cannot be forced to flow through, and a cut-and-raised portion is provided on the side of the compartment where the cooling air cannot be forced through. The semiconductor power converter characterized by the above-mentioned. The power converter according to claim 1 , wherein the partition wall is made of a flexible insulating synthetic resin thin plate. The partition wall made of the insulating synthetic resin thin plate having flexibility is fitted to the partition wall and a notch for fitting provided in a corresponding portion of the frame of the box to form a box frame. The power converter according to claim 2 , wherein the power converter is fixed. A partition chamber in which the cooling air can be forced through is formed above and below the box, and a partition chamber in which the cooling air cannot be forced through is formed between the compartments. The connecting terminal portions of the component devices housed in the chamber are exposed to the adjacent compartments where the cooling air cannot be forced through the partition walls, and in the compartments where the cooling air cannot be forced, The electrical connection of the component apparatus accommodated in the division chamber in which the forced flow of the said cooling air is possible by connecting between connection terminal parts by a connection conductor is given in any one of Claim 1 to 3 characterized by the above-mentioned. The power converter described.

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