Power unit mounting structure of liquid-cooled frequency converter

Abstract

The utility model relates to a liquid cooling frequency converter power unit installation structure, comprising a liquid cooling plate, a rectification module, a capacitor module, an inversion module, a reactor, a control assembly, an inversion laminated busbar and a capacitor laminated busbar, the inversion module is installed on the inversion laminated busbar, the capacitor module is installed on the capacitor laminated busbar, and the capacitor module is installed on the liquid cooling plate. The liquid cooling plate, the rectification module, the inversion module, the capacitor module and the control assembly are sequentially arranged in a laminated mode, the rectification module and the inversion laminated busbar are fixedly installed on the liquid cooling plate through an insulation connection structure, and the capacitor laminated busbar is fixedly installed on the inversion laminated busbar through an insulation connection structure. The control assembly is arranged above the capacitor laminated busbar and is fixedly mounted on the liquid cooling plate; and two ends of the reactor are respectively connected with the rectifier module and the capacitor laminated busbar through copper bars. The installation structure is simple and compact in design, high in modularization degree, good in cooling effect, and capable of effectively reducing stray inductance and guaranteeing the electrical performance of the power unit.

Description

Technical Field

[0001] The utility model relates to the technical field of frequency converters, and particularly relates to an installation structure of a liquid-cooled frequency converter power unit. Background Art

[0002] Liquid cooling is a relatively common method in industrial liquid cooling methods, and frequency converters have great advantages in special occasions with high protection levels and high power. Compared with traditional air-cooled frequency converters, liquid-cooled frequency converters can more effectively solve the heat dissipation problem, thereby greatly reducing the volume of high-power frequency converters and making their performance more stable. Liquid-cooled frequency converters have a history of nearly ten years in Europe and are widely used in occasions with high power, high protection levels and limited space, such as ships and locomotives.

[0003] As Figure 1 shown is the circuit schematic diagram of the frequency converter. As Figure 1 shown, the main devices in the primary circuit of a high-power frequency converter, such as a rectifier bridge, an IGBT-based inverter module, filter capacitors, reactors, etc., form a power unit. The power unit is the core of the frequency converter and plays a decisive role in the electrical performance of the frequency converter. The externally input three-phase power supply passes through the switch power supply module (such as a circuit breaker) via the R, S, and T three-phase power supply copper bars and then is connected to the three-phase rectification module. The L phase at the output end of the rectification module is connected to the reactor, and the N phase at the output end of the rectification module is connected to the N phase of the capacitor module and the N phase of the inverter module. After the reactor is connected in series, its output end is connected to the L phase of the capacitor module and the L phase of the inverter module.

[0004] The externally input three-phase power supply is rectified into direct current after passing through the rectification module. The direct current reduces harmonic interference after passing through the reactor, and then the peak voltage in the direct current is filtered out after passing through the filter circuit composed of the resistor module and the capacitor module, making the direct current more stable; then the filtered direct current is input into the inverter module, and the control and drive unit controls the operation of the inverter module, thereby inverting the direct current into three-phase electricity with a desired frequency and then supplying power to the load (such as motor M). At the same time, the three-phase current output by the inverter module is monitored in real time through a current sensor and fed back to the control and drive unit to achieve closed-loop control of the output. The liquid-cooled plate in the liquid-cooled frequency converter is the most critical component for heat dissipation, and the heat-generating devices such as the IGBT module and the rectifier bridge of the power unit are concentratedly arranged on it. The devices in the power unit are often connected using wires or copper bars, and the setting of a large number of wires and copper bars easily causes complex wire management inside the device, which is not conducive to the miniaturization design of the device. Due to the increasing market requirements for device miniaturization, an optimized installation structure of the liquid-cooled frequency converter power unit needs to be designed to facilitate the miniaturization of the liquid-cooled frequency converter device. Summary of the Utility Model

[0005] Based on the above description, the present utility model provides an installation structure for a liquid-cooled frequency converter power unit to solve the problem of miniaturization of the installation structure of the liquid-cooled frequency converter power unit.

[0006] The technical solution of the present utility model for solving the above technical problems is as follows: An installation structure for a liquid-cooled frequency converter power unit includes a liquid-cooled plate, a rectification module, a capacitor module, an inversion module, a reactor, and a control component, and further includes an inversion laminated busbar and a capacitor laminated busbar. The inversion module is installed on the inversion laminated busbar, the capacitor module is installed on the capacitor laminated busbar, the liquid-cooled plate, the rectification module, the inversion module, the capacitor module, and the control component are sequentially stacked, the rectification module and the inversion laminated busbar are fixedly installed on the liquid-cooled plate through an insulating connection structure, the capacitor laminated busbar is fixedly installed on the inversion laminated busbar through an insulating connection structure, the control component is arranged above the capacitor laminated busbar and is fixedly installed on the liquid-cooled plate through an insulating connection structure; both ends of the reactor are respectively connected to the rectification module and the capacitor laminated busbar through copper bars.

[0007] On the basis of the above technical solution, the present utility model can be further improved as follows.

[0008] Further, a refrigerant channel is provided in the liquid-cooled plate, the refrigerant channel is provided with a liquid inlet and a liquid outlet, and the liquid inlet and the liquid outlet are arranged on a surface of the liquid-cooled plate facing away from the rectification module and the inversion laminated busbar.

[0009] Further, the rectification module includes a plurality of rectifier bridges, and all the rectifier bridges are arranged side by side on the liquid-cooled plate; the inversion laminated busbar is arranged adjacent to the rectification module, and the inversion laminated busbar is fixedly connected to the liquid-cooled plate through a plurality of first insulating columns.

[0010] Further, the three-phase inversion bridge arms of the inversion module are arranged in a pin shape on the inversion laminated busbar; the inversion laminated busbar includes a P-layer inversion busbar and an N-layer inversion busbar which are stacked and insulated from each other. The P-layer inversion busbar is connected to the positive input end of the inversion module, the N-layer inversion busbar is connected to the negative input end of the inversion module, and the three-phase output ends of the inversion module are connected to three-phase output copper bars.

[0011] Further, it further includes a three-phase current sensor, the three-phase current sensor is installed on the liquid-cooled plate and is connected to the three-phase output copper bars, and the three-phase current sensor is electrically connected to the control component.

[0012] Further, the capacitor laminated busbar is fixedly installed on the inverter laminated busbar through a plurality of second insulating columns. The capacitor laminated busbar includes N-layer capacitor busbars, P-layer capacitor busbars, and C-layer capacitor busbars that are sequentially laminated and insulated from each other. The P-layer capacitor busbar is electrically connected to the P-layer inverter busbar through a first transfer busbar, and the N-layer capacitor busbar is connected to the N-layer inverter busbar through a second transfer busbar; the capacitor module includes a plurality of filter capacitors, and the plurality of filter capacitors are divided into a first capacitor group and a second capacitor group. The filter capacitors in the first capacitor group are connected in parallel, and the filter capacitors in the second capacitor group are connected in parallel; the positive electrode of the first capacitor group is connected to the P-layer capacitor busbar, and the negative electrode of the first capacitor group and the positive electrode of the second capacitor group are both connected to the C-layer capacitor busbar, and the negative electrode of the second capacitor group is connected to the N-layer capacitor busbar.

[0013] Further, the control component includes an upper-layer PCBA, a lower-layer PCBA, and a PCBA mounting board that are sequentially laminated. The upper-layer PCBA, the lower-layer PCBA, and the PCBA mounting board are insulated from each other; the PCBA mounting board is disposed above the capacitor laminated busbar and is fixedly installed on the liquid cooling plate through a rigid support structure. The upper-layer PCBA and the lower-layer PCBA are respectively fixedly connected to the PCBA mounting board; a control and drive unit of the liquid cooling frequency converter is disposed on the upper-layer PCBA, and the control and drive unit is electrically connected to the inverter module through a wire; a resistor module is disposed on the lower-layer PCBA, and the resistor module includes a first resistor module and a second resistor module. The first resistor module is connected in parallel with the first capacitor group, and the first capacitor group is connected in parallel with the second capacitor group.

[0014] Further, a plurality of capacitor avoidance holes are provided on the PCBA mounting board, and each of the filter capacitors in the capacitor module penetrates through the capacitor avoidance holes.

[0015] Further, a fan is also provided on the capacitor laminated busbar. The air outlet end of the fan is oriented towards the capacitor module, and the control end of the fan is electrically connected to the control and drive unit.

[0016] Further, an insulating layer is provided between the rectifier module and the inverter laminated busbar, an insulating layer is provided between the P-layer inverter busbar and the N-layer inverter busbar of the inverter laminated busbar, and insulating layers are respectively provided between the N-layer capacitor busbar and the P-layer capacitor busbar, between the P-layer capacitor busbars, and between the C-layer capacitor busbars of the capacitor laminated busbar.

[0017] Compared with the prior art, the technical solution of the present application has the following beneficial technical effects:

[0018] The installation structure of the liquid-cooled inverter power unit of the present utility model stacks the power units on the liquid-cooled plate to reduce the equipment space; at the same time, the rectifier module and the inverter module with relatively large heat generation are arranged close to the liquid-cooled plate, which can achieve a better liquid-cooling effect. The electrical connection is carried out through the stacked busbar. Using the stacked busbar as the current transmission component can provide structural support and meet the electrical performance, making the overall design simple and compact, with a high degree of modularization, effectively reducing the stray inductance and ensuring the electrical performance of the power unit. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the working principle of a commonly used inverter;

[0020] Figure 2 It is a schematic diagram of the usage scenario of the installation structure of the liquid-cooled inverter power unit provided by the embodiment of the present utility model;

[0021] Figure 3 It is a schematic diagram of the overall installation structure of the liquid-cooled inverter power unit provided by the embodiment of the present utility model;

[0022] Figure 4 It is an exploded view of the installation structure of the liquid-cooled inverter power unit provided by the embodiment of the present utility model.

[0023] In the drawings, the list of components represented by each reference numeral is as follows:

[0024] 1, cabinet; 2, switch power supply module; 3, liquid-cooled plate; 4, rectifier module, 401, rectifier bridge, 402, first insulating paper; 5, inverter module; 6, inverter stacked busbar, 601, P-layer inverter busbar, 602, N-layer inverter busbar, 603, second insulating paper; 7, capacitor stacked busbar, 701, N-layer capacitor busbar, 7011, first avoidance hole, 702, P-layer capacitor busbar, 7021, second avoidance hole, 703, C-layer capacitor busbar, 7031, third avoidance hole, 704, third insulating paper, 705, fourth insulating paper; 8, capacitor module; 9, control component, 901, upper-layer PCBA, 902, lower-layer PCBA, 903, PCBA mounting plate, 9031, capacitor avoidance hole, 904, PCBA heat dissipation plate; 10, reactor; 11, first insulating column; 12, second insulating column; 13, first transfer row; 14, second transfer row; 15, support column; 16, fan; 17, three-phase output copper bar; 18, three-phase current sensor. Detailed Embodiments

[0025] To facilitate the understanding of the present application, the present application will be described more comprehensively with reference to the relevant accompanying drawings. Embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terms used in the specification of this application herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0027] It can be understood that spatial relationship terms such as "under", "below", "beneath", "underneath", "above", "over" etc. can be used herein to describe the relationship of one element or feature shown in the drawings with other elements or features. It should be understood that, in addition to the orientation shown in the drawings, spatial relationship terms also include different orientations of the device during use and operation. For example, if the device in the drawing is flipped, the element or feature described as "under other elements" or "beneath it" or "under it" will be oriented "above" other elements or features. Therefore, the exemplary terms "under" and "beneath" can include both the upper and lower orientations. In addition, the device can also include other orientations (such as rotating 90 degrees or other orientations), and the spatial descriptive terms used herein are accordingly interpreted.

[0028] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediate element. In the following embodiments, "connection", if there is an electrical signal or data transfer between the connected circuits, modules, units, etc., should be understood as "electrically connected", "communicatively connected", etc.

[0029] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprise / include" or "have" etc. specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.

[0030] As Figure 1 shown is a schematic diagram of the principle of a commonly used frequency converter circuit in the prior art. As Figure 1As shown in the figure, when a common frequency converter is working, the three-phase power supply R / S / T input externally is rectified by the power management module and then input into the rectification module 4. The rectification module 4 outputs direct current, which reaches the reactor L1 after passing through the soft start module composed of the charging capacitor C4, the soft start switch K1, and the resistor R1. After passing through the reactor L1, the direct current reduces the harmonic interference, and then passes through the filter circuit composed of the resistor module (resistors R2, R3) and the capacitor module (capacitors C5, C6) to filter out the interference voltage in the direct current, making the direct current more stable. Then, the filtered direct current is input into the DC input terminal of the inverter module IPM, where the direct current is inverted into three-phase electricity with the desired frequency and then supplies power to the load (such as the motor M). The control and drive unit controls the operation of the inverter module IPM and can also control the operation of the soft start module. At the same time, the three-phase current output by the inverter module IPM is monitored in real time through the current sensor and fed back to the control and drive unit to achieve closed-loop control of the output.

[0031] The installation structure of the liquid-cooled frequency converter power unit provided in this embodiment is based on the above circuit working principle. The main improvement lies in the installation structure of the liquid-cooled frequency converter power unit, and there is no substantial change to the circuit working principle.

[0032] As Figure 2 shown is a schematic diagram of the applicable scenario of the installation structure of the liquid-cooled frequency converter power unit provided in the embodiment of the present invention. As Figure 2 shown, the entire installation structure of the liquid-cooled frequency converter power unit can be installed on the frame inside the cabinet 1 of the frequency converter, and is connected to the external three-phase power supply through the switching power supply module 2 provided inside the cabinet 1.

[0033] As Figure 3 shown is a three-dimensional structure schematic diagram of the installation structure of the liquid-cooled frequency converter power unit provided in the embodiment of the present invention. Figure 4 It is Figure 3 an exploded view of the overall structure.

[0034] Combined with Figures 2 to 4As shown in the figure, an installation structure of a liquid-cooled inverter power unit provided by an embodiment of the present utility model includes a liquid-cooled plate 3, a rectification module 4, a capacitor module 8, an inversion module 5, a reactor 10, and a control component 9. It further includes an inversion laminated busbar 6 and a capacitor laminated busbar 7. The inversion module 5 is installed on the inversion laminated busbar 6, the capacitor module 8 is installed on the capacitor laminated busbar 7. The liquid-cooled plate 3, the rectification module 4, the inversion module 5, the capacitor module 8, and the control component 9 are sequentially arranged in a laminated manner. The rectification module 4 and the inversion laminated busbar 6 are fixedly installed on the liquid-cooled plate 3 through an insulating connection structure. The capacitor laminated busbar 7 is fixedly installed on the inversion laminated busbar 6 through an insulating connection structure. The control component 9 is arranged above the capacitor laminated busbar 7 and is fixedly installed on the liquid-cooled plate 3 through an insulating connection structure. The control and drive unit of the inverter is arranged on the control component 9. The reactor 10 is installed on a support frame in the cabinet 1. One end of the reactor 10 is connected to the output end of the rectification module 4 through a certain copper busbar, and one end of the reactor 10 is connected to the capacitor laminated busbar 7 through another copper busbar, thereby being electrically connected to the capacitor module 8.

[0035] It can be understood that Figure 1 the soft start module shown includes a soft start switch and a soft start resistor R1 connected in parallel with each other, and further includes a charging capacitor C4 connected in parallel with the rectification module 4. Since the soft start module is not an essential module inside the inverter (the operation of the inverter can be controlled by setting a switching power supply module 2 at the external power supply inlet), and it is not a module with a large heat generation in the inverter. Therefore, the installation structure of the liquid-cooled inverter power unit provided in this embodiment does not include Figure 1 the soft start module therein. In an application scenario where a soft start module needs to be set, the soft start module can be set on the control module 9 and is electrically connected to the installation structure of the liquid-cooled inverter power unit in this embodiment according to the circuit structure of the inverter. For the installation structure of the liquid-cooled inverter power unit of the present utility model, each component module of the power unit is arranged in a laminated manner on the liquid-cooled plate 3 to reduce the equipment space. At the same time, the rectification module 4 and the inversion module 5 with a large heat generation are arranged close to the liquid-cooled plate 3, which can achieve a better liquid-cooling effect. Electrical connection is carried out through the laminated busbar. Using the laminated busbar as a current transmission component can not only provide structural support but also meet the electrical performance, making the overall design structure simple and compact, with a high degree of modularization, effectively reducing stray inductance, and ensuring the electrical performance of the power unit.

[0036] In one possible implementation, a refrigerant channel is provided in the liquid cooling plate 3. The refrigerant channel is provided with a liquid inlet and a liquid outlet, and the liquid inlet and the liquid outlet are arranged on a side of the liquid cooling plate 3 facing away from the rectification module 4 and the inverter laminated busbar 6. The refrigerant in the refrigerant channel can be cooling water, cooling oil or other cooling media. For the sake of simplicity and understandability of the following description, cooling water is taken as an example in the embodiments of the present invention.

[0037] During the operation of the frequency converter, the cooling water enters the refrigerant channel from the liquid inlet, flows out from the liquid outlet after passing through the winding refrigerant channel, and takes away the heat generated by the power unit, thereby cooling the power unit of the frequency converter. The liquid inlet and the liquid outlet are arranged away from the power unit, which can avoid the problem of accidental leakage of cooling water and causing a short circuit of the frequency converter, and improve the safety performance of the equipment.

[0038] In one possible implementation, the rectification module 4 includes a plurality of rectifier bridges 401, and all the rectifier bridges 401 are arranged side by side on the liquid cooling plate 3; the inverter laminated busbar 6 is arranged adjacent to the rectification module 4, and the inverter laminated busbar 6 is fixedly connected to the liquid cooling plate 3 through a plurality of first insulating columns 11, and the first insulating columns 11 are locked on the liquid cooling plate 3 by screws.

[0039] For example Figure 4 As shown, the rectification module 4 includes 9 rectifier bridges 401, and the 9 rectifier bridges 401 are arranged side by side on the liquid cooling plate 3. When making electrical connections, the 9 rectifier bridges 401 are evenly divided into 3 groups to form Figure 1 As shown, the three-phase rectifier bridge 401 structure; the 3 rectifier bridges 401 in each group are connected in parallel to ensure the reliability of the operation of the rectification module 4. Both the rectification module 4 and the inverter module 5 are components with relatively large heat generation, so they are arranged close to the liquid cooling plate 3 to achieve a better heat dissipation effect. The first insulating column 11 provides structural support for the inverter laminated busbar 6 and can ensure the electrical insulation performance between the inverter laminated busbar 6 and the liquid cooling plate 3.

[0040] To further ensure the electrical performance of the equipment, a first insulating paper 402 can be arranged outside the rectification module 4. The first insulating paper 402 has a U-shaped groove structure. The rectification module 4 is arranged in the U-shaped groove of the first insulating paper 402, and the rectification module 4 is electrically isolated from the liquid cooling plate 3 and the inverter laminated busbar 6 through the first insulating paper 402 to ensure the safety distance.

[0041] In one possible implementation, the three-phase inverter bridge arms of the inverter module 5 are arranged in a pin shape on the inverter laminated busbar 6; for example Figure 4As shown, the inverter module 5 includes 12 IGBTs. Each three-phase inverter arm of the inverter module 5 includes 4 IGBTs. The upper arm of each three-phase inverter arm is composed of two IGBTs in parallel, and the lower arm of each three-phase inverter arm is also composed of two IGBTs in parallel. Since IGBTs generate a large amount of heat during operation, the three-phase inverter arms are arranged in a staggered shape like a product character, which is beneficial to improving the heat dissipation effect. As Figure 4 shown, the inverter laminated busbar 6 includes a P-layer inverter busbar 601 and an N-layer inverter busbar 602 that are stacked in sequence from top to bottom and insulated from each other. The P-layer inverter busbar 601 is connected to the positive input terminal of the inverter module 5, and the N-layer inverter busbar 602 is connected to the negative input terminal of the inverter module 5. The three-phase output terminals of the inverter module 5 are connected to the three-phase output copper busbar 17. In order to further improve the electrical safety performance, a second insulating paper 603 is provided between the P-layer inverter busbar 601 and the N-layer inverter busbar 602, and the four sides of the second insulating paper 603 have flanges to increase the safety distance. While ensuring the electrical clearance and creepage distance, the dimensional distance between the P-layer inverter busbar 601 and the N-layer inverter busbar 602 can be reduced.

[0042] In one possible implementation, as Figure 4 shown, it further includes a three-phase current sensor 18 (equivalent to Figure 1 the current sensors CT1 to CT3 shown, and a Hall sensor can be preferably used). The three-phase current sensor 18 is installed on the liquid cooling plate 3 and connected to the three-phase output copper busbar 17. The three-phase current sensor 18 is electrically connected to the control component 9. The three-phase output copper busbar 17 is used to connect an external load, such as Figure 1 the motor M in

[0043] In one possible implementation, the capacitor laminated busbar 7 is fixedly installed on the inverter laminated busbar 6 through a plurality of second insulating columns 12. The capacitor laminated busbar 7 includes an N-layer capacitor busbar 701, a P-layer capacitor busbar 702, and a C-layer capacitor busbar 703 that are stacked in sequence and insulated from each other. The P-layer capacitor busbar 702 is electrically connected to the P-layer inverter busbar 601 through a first transfer busbar 13, and the N-layer capacitor busbar 701 is connected to the N-layer inverter busbar 602 through a second transfer busbar 14; the capacitor module 8 includes a number of filter capacitors, and a number of the filter capacitors are divided into a first capacitor group (equivalent to Figure 1 the capacitor C5 in Figure 1In the capacitor C6), the filtering capacitors in the first capacitor group are connected in parallel, and the filtering capacitors in the second capacitor group are connected in parallel; the positive pole of the first capacitor group is connected to the P-layer capacitor busbar 702, and the negative pole of the first capacitor group and the positive pole of the second capacitor group are both connected to the C-layer capacitor busbar 703, and the negative pole of the second capacitor group is connected to the N-layer capacitor busbar 701. For example Figure 4 As shown, in this embodiment, the capacitor module 8 is composed of 24 filtering capacitors. The 24 filtering capacitors are divided into two groups and connected in series to the circuit for filtering the circuit.

[0044] In order to further reduce the space distance between adjacent layer busbars in the capacitor stack busbar 7, a plurality of first avoidance holes 7011 can be provided on the N-layer capacitor busbar 701 corresponding to the capacitor connection points on the P-layer capacitor busbar 702 / C-layer capacitor busbar 703, and a plurality of second avoidance holes 7021 are provided on the P-layer capacitor busbar 702 corresponding to the first avoidance holes 7011 and the capacitor connection points on the C-layer capacitor busbar 703, and a plurality of third avoidance holes 7031 are provided on the C-layer capacitor busbar 703 corresponding to the second avoidance holes 7021 to avoid the pins of each capacitor and the capacitor connection points of each capacitor on the busbar, and ensure the safety distance of the capacitor stack busbar 7.

[0045] In order to further improve the electrical safety performance, a third insulating paper 704 is provided between the N-layer capacitor busbar 701 and the P-layer capacitor busbar 702, and a fourth insulating paper 705 is provided between the P-layer capacitor busbar 702 and the C-layer capacitor busbar 703. While ensuring the electrical clearance and creepage distance, the dimensional distance between the N-layer capacitor busbar 701 and the P-layer capacitor busbar 702, and between the P-layer capacitor busbar 702 and the C-layer capacitor busbar 703 can be reduced.

[0046] More specifically, in a certain implementation scenario, such as Figure 4 As shown, the capacitor stack busbar 7 from top to bottom is the N-layer capacitor busbar 701, the P-layer capacitor busbar 702, and the C-layer capacitor busbar 703 in sequence. A third insulating paper 704 is sandwiched between the N-layer capacitor busbar 701 and the P-layer capacitor busbar 702, and a fourth insulating paper 705 is sandwiched between the P-layer capacitor busbar 702 and the C-layer capacitor busbar 703. After the three stacked busbars and the two insulating papers are stacked in sequence, they are fixed to all the filtering capacitors by screws to form an integral component.

[0047] Preferably, 24 filter capacitors are arranged in the capacitor module 8, which are laid out on the uppermost layer of the capacitor laminated busbar 7 (i.e., on the N-layer capacitor busbar 701). The positive and negative poles of the filter capacitors face downward. The filter capacitors are arranged in a 6-column × 4-row matrix. The positive poles of the filter capacitors in the first and third rows are connected to the P-layer capacitor busbar 702, and the negative poles of the filter capacitors in the second and fourth rows are connected to the N-layer capacitor busbar 701. The two groups of filter capacitors are connected in series through the C-layer capacitor busbar 703, that is, the C-layer capacitor busbar 703 connects the negative poles of the capacitors in the first and third rows and the positive poles of the capacitors in the second and fourth rows.

[0048] Preferably, as Figure 4 shown, two positioning posts with asymmetric positions can be riveted on the N-layer capacitor busbar 701 of the capacitor laminated busbar 7 to facilitate positioning and assembly during lamination. The C-layer capacitor busbar 703 is folded downward around the perimeter to increase the support strength. Six M4 wiring screw holes are provided on each of the front and rear folded edges. The left and right sides of the third insulating paper 704 have folded edges to increase the safety distance.

[0049] Two first transfer buses 13 and two second transfer buses 14 are correspondingly arranged on the left and right sides of the capacitor laminated busbar 7. There are two pairs of pins on both the left and right sides of the N-layer capacitor busbar 701 and the P-layer capacitor busbar 702, which are respectively connected to the four transfer buses. The two first transfer buses 13 and the two second transfer buses 14 are then connected to the lower-layer inverter laminated busbar 6. Two M4 wiring screw holes are provided on each of the first transfer bus 13 and the second transfer bus 14.

[0050] In one possible implementation, as Figure 4 shown, the control component 9 includes an upper-layer PCBA 901, a lower-layer PCBA 902, and a PCBA mounting plate 903 that are stacked in sequence. The upper-layer PCBA 901, the lower-layer PCBA 902, and the PCBA mounting plate 903 are insulated from each other. The PCBA mounting plate 903 is arranged above the capacitor laminated busbar 7 and is fixedly installed on the liquid cooling plate 3 through a rigid support structure (such as a sheet metal part). The upper-layer PCBA 901 and the lower-layer PCBA 902 are respectively fixedly connected to the PCBA mounting plate 903. A control and drive unit of the liquid cooling frequency converter is arranged on the upper-layer PCBA 901. The control and drive unit is electrically connected to the inverter module 5 through a wire. The soft start switch can also be arranged on the upper-layer PCBA 901. The soft start switch can be implemented by a relay and is controlled by the control and drive unit. More specifically, the control and drive unit includes as Figure 1The control module and its peripheral circuits shown, as well as the drive protection circuit for driving the inverter module 5, etc. In order to improve the heat dissipation effect of the upper-layer PCBA901, a PCBA heat dissipation plate 904 can also be set in regions on the upper-layer PCBA901. A resistor module is provided on the lower-layer PCBA902, and the resistor module includes a first resistor module and a second resistor module (and a soft-start resistor R1). The first resistor module (equivalent to Figure 1 the resistor R2 shown) is in parallel with the first capacitor bank (equivalent to Figure 1 the capacitor C5 shown), and the second resistor module (equivalent to Figure 1 the resistor R3 shown) is in parallel with the second capacitor bank (equivalent to Figure 1 the capacitor C6 shown).

[0051] In one possible implementation, in combination with Figure 3 and Figure 4 shown, a plurality of capacitor avoidance holes 9031 are provided on the PCBA mounting plate 903. Each filtering capacitor in the capacitor module 8 passes through the capacitor avoidance holes 9031 to reduce the mounting size of the control component 9. In order to reliably support the accommodation space of the capacitor module 8, a plurality of support columns 15 are also fixedly provided on the PCBA mounting plate 903 to prevent the lower-layer PCBA902 above the PCBA mounting plate 903 from interfering with the capacitor module 8.

[0052] In one possible implementation, a fan 16 is also provided on the capacitor stacked busbar 7 or the PCBA mounting plate 903. The air outlet end of the fan 16 is arranged towards the capacitor module 8, and the control end of the fan 16 is electrically connected to the control and drive unit. Since the number of capacitors is large and the heat generation is large, and because they are stacked above the inverter module 5 and are slightly far from the liquid cooling plate 3, and in addition, the control component 9 also generates heat during operation. In this embodiment, the air outlet direction of the fan 16 is arranged towards the capacitor, which can accelerate the air flow at the capacitor and achieve efficient heat dissipation for the capacitor and the control component 9.

[0053] In this embodiment, the surfaces of all stacked busbars are nickel-plated. The weak parts of the copper busbar cross-section should meet the current-carrying requirements. The minimum electrical clearance and the minimum creepage distance between each pin, and between the pin and the sheet metal and the liquid cooling plate 3 should all meet the electrical safety regulations requirements, and each insulating paper also meets the electrical insulation withstand voltage requirements.

[0054] An installation structure of a liquid-cooled frequency converter power unit provided by the present utility model stacks the main heat-generating components of the frequency converter power unit on a liquid-cooled plate 3 to reduce the equipment space; connects each layer of components through multiple insulators to make the entire power unit assembly support stable and firm, and the entire power unit assembly is supported and fixed on the frame of the liquid-cooled frequency converter cabinet 1. At the same time, the rectifier module 4 and the inverter module 5 with relatively large heat generation are arranged close to the liquid-cooled plate 3, so as to achieve a better liquid-cooling heat dissipation effect, and the capacitors and the control component 9 are air-cooled by a fan 16, obtaining an excellent comprehensive heat dissipation effect. Electrical connection is carried out through laminated busbars, and insulating columns and insulating paper and other facilities are arranged between the busbars of adjacent layers to prevent accidental conduction between adjacent busbars and ensure the electrical safety performance between the laminated busbars. Using the laminated busbars as current transmission components can provide structural support and meet electrical performance requirements, making the overall design structure simple and compact, simplifying the internal wire management of the equipment, having a high degree of modularization, effectively reducing stray inductance, and ensuring the electrical performance of the power unit.

[0055] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A liquid-cooled inverter power unit installation structure, comprising a liquid cooling plate (3), a rectifier module (4), a capacitor module (8), an inverter module (5), a reactor (10) and a control component (9), characterized in that: The invention also comprises an inverter stacked busbar (6) and a capacitor stacked busbar (7), wherein the inverter module (5) is mounted on the inverter stacked busbar (6), and the capacitor module (8) is mounted on the capacitor stacked busbar (7); the liquid cooling plate (3), the rectifier module (4), the inverter module (5), the capacitor module (8) and the control component (9) are stacked in sequence; the rectifier module (4) and the inverter stacked busbar (6) are fixedly mounted on the liquid cooling plate (3) through an insulating connection structure; the capacitor stacked busbar (7) is fixedly mounted on the inverter stacked busbar (6) through an insulating connection structure; and the control component (9) is arranged above the capacitor stacked busbar (7) and fixedly mounted on the liquid cooling plate (3) through an insulating connection structure; and the two ends of the reactor (10) are respectively connected to the rectifier module (4) and the capacitor stacked busbar (7) through a copper busbar.

2. According to claim 1, a liquid-cooled inverter power unit installation structure is characterized in that: A refrigerant channel is provided in the liquid cooling plate (3), and the refrigerant channel is provided with a liquid inlet and a liquid outlet, and the liquid inlet and the liquid outlet are arranged on a side of the liquid cooling plate (3) away from the rectifier module (4) and the inverter stacked busbar (6).

3. The liquid-cooled inverter power unit installation structure according to claim 1, characterized in that: The rectifier module (4) comprises a plurality of rectifier bridges (401), and all of the rectifier bridges (401) are arranged side by side on the liquid cooling plate (3); the inverter stacked busbar (6) is arranged adjacent to the rectifier module (4), and the inverter stacked busbar (6) is fixedly connected to the liquid cooling plate (3) via a plurality of first insulating columns (11).

4. The liquid-cooled inverter power unit installation structure according to claim 3, characterized in that: The three-phase inverter bridge arm of the inverter module (5) is arranged in a herringbone shape on the inverter stacked busbar (6); the inverter stacked busbar (6) comprises a P-layer inverter busbar (601) and an N-layer inverter busbar (602) which are stacked and insulated from each other, the P-layer inverter busbar (601) is connected to the positive input terminal of the inverter module (5), the N-layer inverter busbar (602) is connected to the negative input terminal of the inverter module (5), and the three-phase output terminal of the inverter module (5) is connected to the three-phase output copper busbar (17).

5. The liquid-cooled inverter power unit installation structure according to claim 4, characterized in that: It also includes a three-phase current sensor (18), which is mounted on the liquid cooling plate (3) and connected to the three-phase output copper busbar (17), and is electrically connected to the control component (9).

6. A liquid-cooled inverter power unit installation structure according to claim 4 or 5, characterized in that: The capacitor stack busbar (7) is fixedly mounted on the inverter stack busbar (6) via a plurality of second insulating columns (12); the capacitor stack busbar (7) comprises an N-layer capacitor busbar (701), a P-layer capacitor busbar (702) and a C-layer capacitor busbar (703) which are stacked in sequence and insulated from each other; the P-layer capacitor busbar (702) is electrically connected to the P-layer inverter busbar (601) via a first transfer bar (13); the N-layer capacitor busbar (701) is electrically connected to the N-layer inverter busbar (603) via a second transfer bar (14). The capacitor module (8) comprises a plurality of filter capacitors, the plurality of filter capacitors being divided into a first capacitor group and a second capacitor group, the filter capacitors in the first capacitor group being connected in parallel, and the filter capacitors in the second capacitor group being connected in parallel; the positive electrode of the first capacitor group being connected to the P-layer capacitor busbar (702), the negative electrode of the first capacitor group and the positive electrode of the second capacitor group being connected to the C-layer capacitor busbar (703), and the negative electrode of the second capacitor group being connected to the N-layer capacitor busbar (701).

7. The liquid-cooled inverter power unit installation structure according to claim 6, characterized in that: The control component (9) comprises an upper PCBA (901), a lower PCBA (902) and a PCBA mounting plate (903) which are stacked in sequence, and the upper PCBA (901), the lower PCBA (902) and the PCBA mounting plate (903) are insulated from each other; the PCBA mounting plate (903) is arranged above the capacitor stack busbar (7) and is fixedly mounted on the liquid cooling plate (3) through a rigid support structure, and the upper PCBA (901) and the lower PCBA (902) are respectively fixedly connected to the PCBA mounting plate (903); a control and drive unit of a liquid cooling inverter is arranged on the upper PCBA (901), and the control and drive unit is electrically connected to the inverter module (5) through a wire; and a resistor module is arranged on the lower PCBA (902), and the resistor module comprises a first resistor module and a second resistor module, the first resistor module is connected in parallel with the first capacitor group, and the first capacitor group is connected in parallel with the second capacitor group.

8. The liquid-cooled inverter power unit installation structure according to claim 7, characterized in that: The PCBA mounting plate (903) is provided with a plurality of capacitor avoidance holes (9031), and each of the filter capacitors in the capacitor module (8) passes through the capacitor avoidance holes (9031).

9. The liquid-cooled inverter power unit installation structure according to claim 8, characterized in that: A fan (16) is also provided on the capacitor stack busbar (7), the air outlet end of the fan (16) is arranged toward the capacitor module (8), and the control end of the fan (16) is electrically connected to the control and drive unit.

10. A liquid-cooled inverter power unit installation structure according to claim 8 or 9, characterized in that: An insulating layer is provided between the rectifier module (4) and the inverter stack busbar (6), an insulating layer is provided between the P-layer inverter busbar (601) and the N-layer inverter busbar (602) of the inverter stack busbar (6), and insulating layers are provided between the N-layer capacitor busbar (701) and the P-layer capacitor busbar (702), between the P-layer capacitor busbars (702), and between the C-layer capacitor busbars (703) of the capacitor stack busbar (7).

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