A frequency converter

Abstract

This application relates to a frequency converter, comprising: multiple unit modules, which can be combined to form the main circuit of the frequency converter, each unit module being provided with a connection port and a first communication port; a control unit, which is provided with multiple second communication ports and is communicatively connected to the first communication port of each unit module through the multiple second communication ports; and a unit connector, which is provided with multiple parallel ports and is connected to the connection port of each unit module through the multiple parallel ports.

Description

Technical Field

[0001] This application relates to the field of electrical equipment technology, and more particularly to a frequency converter. Background Technology

[0002] A variable frequency drive (VFD) is a power control device primarily used to control the speed and torque of an AC motor by adjusting the frequency and voltage of the motor power supply. It is widely used in industrial automation, energy-saving control, and precision speed regulation.

[0003] A frequency converter is a system consisting of an input section (rectifier), an intermediate section (filter), an output section (inverter), and a control section. The working principle of a frequency converter is to convert alternating current (AC) to direct current (DC) through a rectifier, and then convert the DC current back to AC with an adjustable frequency through an inverter. A complete frequency converter must include a three-phase input section (R, S, T), a three-phase output section (U, V, W), and control circuitry.

[0004] When machines require maintenance or malfunctions necessitating on-site disassembly and repair, the complex environment and specific requirements, such as numerous wiring harnesses and prohibitions against open flames, can severely complicate repairs and lead to production line downtime. Directly replacing the entire machine would incur significant costs, especially with high-power machines, where their sheer size makes complete replacement extremely difficult. Utility Model Content

[0005] This application provides a frequency converter to solve the above-mentioned technical problems.

[0006] This application provides a frequency converter, including:

[0007] Multiple unit modules, which can be combined to form the main circuit of the frequency converter, and each unit module is provided with a connection port and a first communication port;

[0008] The control unit is provided with multiple second communication ports, which are respectively connected to the first communication port of each unit module.

[0009] The unit connector is provided with multiple parallel ports, and the connection ports of each unit module are connected through the multiple parallel ports.

[0010] Preferably, the connection ports include: N connection ports, P connection ports and O connection ports, and each of the parallel ports includes: N parallel ports, P parallel ports and O parallel ports;

[0011] The N-connection port, P-connection port, and O-connection port of the multiple unit modules are connected in parallel through the N-parallel port, P-parallel port, and O-parallel port, respectively.

[0012] Preferably, the unit connector includes: an N-parallel conductive sheet, a P-parallel conductive sheet, and an O-parallel conductive sheet, wherein the N-parallel port, the P-parallel port, and the O-parallel port are respectively disposed on the N-parallel conductive sheet, the P-parallel conductive sheet, and the O-parallel conductive sheet.

[0013] Preferably, the N-parallel conductive sheet, P-parallel conductive sheet and O-parallel conductive sheet are stacked, and the N-parallel conductive sheet, P-parallel conductive sheet and O-parallel conductive sheet are isolated from each other by a first insulating sheet and a second insulating sheet, respectively.

[0014] The N parallel port, P parallel port and O parallel port are arranged to avoid each other in the stacking direction, and the first insulating sheet and the second insulating sheet are respectively provided with corresponding first insulating avoidance holes and second insulating avoidance holes.

[0015] Preferably, the unit connector further includes: a third insulating sheet disposed at the topmost point in the stacking direction and a fourth insulating sheet disposed at the bottommost point in the stacking direction;

[0016] The third insulating sheet is provided with a third insulating clearance hole to avoid the N parallel port, P parallel port and O parallel port.

[0017] Preferably, at least one of the N-parallel conductive sheet, P-parallel conductive sheet, and O-parallel conductive sheet is a rigid structure;

[0018] Alternatively, at least one of the first insulating sheet, the second insulating sheet, the third insulating sheet, and the fourth insulating sheet may be a rigid structure.

[0019] Preferably, the N-parallel conductive sheet, P-parallel conductive sheet, and O-parallel conductive sheet have a U-shaped cross-section in the width direction.

[0020] Preferably, the unit module includes: a base, a power module, a power module driver board, and a capacitor sequentially disposed on the base;

[0021] The power module, the power module driver board, and the capacitor are electrically connected.

[0022] Preferably, the capacitor's outer casing is provided with a handle.

[0023] Preferably, the unit module is an inverter unit module, a rectifier unit module, or a filter unit module.

[0024] The technical solutions provided in this application have the following advantages compared with the prior art:

[0025] The inverter provided in this application embodiment has a main circuit formed by combining multiple unit modules. This allows for the creation of different inverter products by combining different types and quantities of unit modules according to actual usage scenarios, thereby reducing the inventory burden on inverter manufacturers. In the event of damage to individual unit modules, the module can be quickly replaced by disassembling its connection to the unit connector and the mounting plate. Furthermore, the unit module and control unit are connected by only a single communication cable, eliminating the need to disassemble the inverter's internal circuit board into multiple and varied wiring harnesses, such as sensor wires, drive wires, and control wires, during machine disassembly and maintenance. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0029] Figure 1 This is a schematic diagram of the inverter structure provided in an embodiment of this application;

[0030] Figure 2 This is a schematic diagram of the unit module structure provided in an embodiment of this application;

[0031] Figure 3 This is an exploded view of the unit module structure provided in the embodiments of this application;

[0032] Figure 4 This is a schematic diagram of the unit connector structure provided in an embodiment of this application;

[0033] Figure 5 This is an exploded view of the unit connector structure provided in an embodiment of this application;

[0034] Figure 6 A schematic diagram of a structure for combining the unit modules provided in the embodiments of this application;

[0035] Figure 7 This is another structural diagram illustrating the combination of unit modules provided in the embodiments of this application.

[0036] Explanation of reference numerals in the attached figures:

[0037] Unit module 1, connection port 11, first communication port 12, N connection port 111, P connection port 112, O connection port 113, base 101, power module 102, power module driver board 103, capacitor 104, base plate 1011, side wall 1012, limiting surface 1013, pressure block 1015, outer shell 1041, handle 1042;

[0038] Control unit 2, second communication port 22;

[0039] Unit connector 3, parallel port 31, N parallel port 311, P parallel port 312, O parallel port 313, N parallel conductive piece 301, P parallel conductive piece 302, O parallel conductive piece 303, first insulating piece 304, second insulating piece 305, third insulating piece 306, fourth insulating piece 307, terminal 309, first terminal clearance hole 3021, second terminal clearance hole 3022, third terminal clearance hole 3033, first insulating clearance hole 3041, second insulating clearance hole 3051, third insulating clearance hole 3061. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0041] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0042] For ease of description, spatial relative terms may be used in the text to describe the relative position or movement of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "front," "back," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure undergoes a positional flip, orientation change, or change of motion, these directional indications will change accordingly. For instance, an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0043] To address the technical problems of high maintenance difficulty and cost of frequency converters in the prior art, this application provides a frequency converter that enables rapid maintenance and reduces maintenance costs. At the same time, the technical solution of this application also reduces the difficulty for manufacturers in stocking up.

[0044] Figure 1 The image shows a frequency converter provided in an embodiment of this application. This frequency converter can be used to adjust the frequency and voltage of the motor power supply to control the speed and torque of an AC motor. Specifically, the line connection structure includes: multiple unit modules 1, a control unit 2, and a unit connector 3.

[0045] In this embodiment, the main circuit of the frequency converter mainly includes an inverter unit module, a rectifier unit module, and a filter unit module. The multiple unit modules 1 can be combined to form the main circuit of the frequency converter, such as... Figure 2 As shown, each unit module 1 is provided with a connection port 11 and a first communication port 12. The connection port 11 is mainly used for parallel connection between each unit module 1 to realize the combination of each unit module into the main circuit of the frequency converter. The first communication port 12 is used to communicate with the control unit 2 through a communication line, so that the control unit 2 can communicate and control each unit module 1.

[0046] As an optional implementation method, combined with Figure 2 and Figure 3As shown, the unit module 1 includes: a base 101, a power module 102, a power module driver board 103, and a capacitor 104 sequentially disposed on the base 101. A connection port 11 and a first communication port 12 are respectively disposed at both ends of the unit module 1. The power module 102, the power module driver board 103, and the capacitor 104 are electrically connected. The power module 102 is positioned against the bottom of the base 101, allowing it to fit against the heat sink during assembly. This effectively conducts the heat generated by the power module to the heat sink, achieving efficient heat dissipation. The power module driver board 103 generates less heat and is placed on top of the power module 102. The capacitor 104 is positioned on top, as there are no other obstructions, thus increasing the capacitor's volume and capacitance.

[0047] Furthermore, the base 101 is composed of a base plate 1011 and side walls 1012 arranged around the base plate 1011. The base plate 1011 and the side walls 1012 enclose the installation space for the power module 102 and the power module drive board 103. The installation space is provided with corresponding fixing structures to fix the power module 102 and the power module drive board 103. The capacitor 104 is directly installed on the top of the side wall 1012 and closes the installation space.

[0048] In one optional embodiment, the base plate 1011 has a rectangular structure, and its two ends are provided with mounting structures for mounting onto the module mounting plate (not shown in the figure). Specifically, as an optional embodiment, the two ends of the base plate 1011 are provided with limiting surfaces 1013, and the base plate 1011 can be pressed onto the mounting plate by limiting blocks 1015.

[0049] In this embodiment, all unit modules 1 of the same or different types adopt the same structural form to facilitate free combination. When unit module 1 is an inverter unit module, power module 102 is an inverter power device; when unit module 1 is a rectifier unit module, power module 102 is a rectifier power device; when unit module 1 is a filter unit module, power module 102 is a filter power device.

[0050] Furthermore, a handle 1042 is provided on the outer shell 1041 of the capacitor 104, which allows the entire unit module 1 to be easily lifted for assembly or disassembly.

[0051] In this embodiment, the control unit 2 is provided with multiple second communication ports 22, which are respectively connected to the first communication port 12 of each unit module 1 to realize communication control of each unit module 1.

[0052] In this embodiment, the unit connector 3 is used to realize the parallel connection between each unit module 1. The unit connector 3 is provided with multiple parallel ports 31, and the multiple parallel ports 31 are connected to the connection port 11 of each unit module 1.

[0053] As a specific implementation method, such as Figure 2 As shown, each unit module 1's connection port 11 includes: N connection port 111, P connection port 112, and O connection port 113, corresponding to, as Figure 4 As shown, the parallel port 31 of the unit connector 3 includes: an N parallel port 311, a P parallel port 312, and an O parallel port 313. The N connection port 111, P connection port 112, and O connection port 113 of the plurality of unit modules 1 are connected in parallel through the N parallel port 311, P parallel port 312, and O parallel port 313, respectively.

[0054] In this embodiment, the unit connector 3 includes: an N-parallel conductive sheet 301, a P-parallel conductive sheet 302, and an O-parallel conductive sheet 303. The N-parallel port 311, the P-parallel port 312, and the O-parallel port 313 are respectively disposed on the N-parallel conductive sheet 301, the P-parallel conductive sheet 302, and the O-parallel conductive sheet 303.

[0055] Furthermore, to achieve compact installation of each unit module 1, the N-parallel conductive sheet 301, P-parallel conductive sheet 302, and O-parallel conductive sheet 303 are stacked, and the port structure is realized by terminals 309 on each conductive sheet. This allows the distance between the ports to be closer, and multiple sets of ports can be implemented in one unit connector 3. Moreover, the N-parallel conductive sheet 301, P-parallel conductive sheet 302, and O-parallel conductive sheet 303 are isolated from each other by a first insulating sheet 304 and a second insulating sheet 305, respectively, thereby preventing short circuits between the conductive sheets.

[0056] To ensure that the ports of the multiple conductive sheets stacked on a single unit connector 3 are independent and not short-circuited, the N-parallel port 311, P-parallel port 312, and O-parallel port 313 are arranged to avoid each other in the stacking direction. This is achieved by providing clearance holes, where the upper conductive sheet provides clearance holes to avoid the ports of the lower conductive sheets. Taking an N-parallel conductive sheet 301 at the bottom, an O-parallel conductive sheet 303 in the middle layer, and a P-parallel conductive sheet 302 at the top as an example, the P-parallel conductive sheet 302 has a first terminal clearance hole 3021 and a second terminal clearance hole 3022 to avoid the N-parallel port 311 and the O-parallel port 312, respectively. The O-parallel conductive sheet 303 requires a third terminal clearance hole 3033 to avoid the O-parallel port 311. Similarly, the first insulating sheet 304 and the second insulating sheet 305 are respectively provided with corresponding first insulating clearance holes 3041 and second insulating clearance holes 3051.

[0057] Furthermore, the unit connector 3 also includes: a third insulating sheet 306 disposed at the top of the stacking direction and a fourth insulating sheet 307 disposed at the bottom of the stacking direction; the third insulating sheet 306 is provided with a third insulating clearance hole 3061 to avoid the N parallel port 311, P parallel port 312 and O parallel port 313.

[0058] To ensure the installation reliability of the unit connector 3, the unit connector 3 as a whole should have a certain degree of rigidity. In this embodiment, at least one of the N-parallel conductive sheet 301, P-parallel conductive sheet 302, and O-parallel conductive sheet 303 is a rigid structure; or, at least one of the first insulating sheet 304, second insulating sheet 305, third insulating sheet 306, and fourth insulating sheet 307 is a rigid structure. As a preferred embodiment, the N-parallel conductive sheet 301, P-parallel conductive sheet 302, and O-parallel conductive sheet 303 are made of conductive copper sheets with a certain thickness, thereby giving the unit connector 3 a certain degree of rigidity.

[0059] As a further improvement, the N-parallel conductive sheet 301, P-parallel conductive sheet 302, and O-parallel conductive sheet 303 have a U-shaped cross-section in the width direction. This increases the overall area of ​​each conductive sheet, enabling it to withstand a larger current. At the same time, the U-shaped structure increases the effective area without increasing the overall width of the unit connector 3, allowing the inverter to be assembled in a more compact space. Furthermore, the U-shaped structure also enhances the overall structural strength of the unit connector 3, making it less prone to bending and thus reducing installation difficulties.

[0060] Based on the above, such as Figure 6 The diagram shows the main circuit of a 710kW four-quadrant frequency converter composed of six inverter unit modules 1a. Figure 1As described above, connecting it to control unit 2 constitutes a frequency converter main body. For example... Figure 7 As shown, three inverter unit modules 1a and one rectifier unit module 1b can be combined to form a 250kW two-quadrant frequency converter. Furthermore, depending on the actual application scenario, different types and quantities of unit modules 1 can be combined to form different frequency converter products, thereby reducing the inventory burden for frequency converter manufacturers. In the event of damage to individual unit modules 1, they can be quickly replaced by disassembling the connection to the unit connector and the connection to the mounting plate. Moreover, the unit module and control unit are connected by only a single communication cable, eliminating the need to disassemble the multiple and varied wiring harnesses (sensor wires, drive wires, control wires, etc.) from the internal circuit board of the frequency converter during machine disassembly and maintenance.

[0061] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0062] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0064] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0065] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0066] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0067] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Since these modifications and variations fall within the scope of the claims and their equivalents, this application also intends to include these modifications and variations.

[0068] The above description describes specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A frequency converter, characterized in that, include: Multiple unit modules (1) can be combined to form the main circuit of the frequency converter. Each unit module (1) is provided with a connection port (11) and a first communication port (12). The control unit (2) is provided with multiple second communication ports (22), which are respectively connected to the first communication port (12) of each unit module (1) through the multiple second communication ports (22); The unit connector (3) is provided with multiple parallel ports (31) and is connected to the connection port (11) of each unit module (1) through the multiple parallel ports (31).

2. The frequency converter according to claim 1, characterized in that, The connection port (11) includes: N connection port (111), P connection port (112) and O connection port (113), and each of the parallel ports (31) includes: N parallel port (311), P parallel port (312) and O parallel port (313). The N connection port (111), P connection port (112) and O connection port (113) of the multiple unit modules (1) are connected in parallel through the N parallel port (311), P parallel port (312) and O parallel port (313), respectively.

3. The frequency converter according to claim 2, characterized in that, The unit connector (3) includes: an N parallel conductive sheet (301), a P parallel conductive sheet (302) and an O parallel conductive sheet (303), wherein the N parallel port (311), the P parallel port (312) and the O parallel port (313) are respectively disposed on the N parallel conductive sheet (301), the P parallel conductive sheet (302) and the O parallel conductive sheet (303).

4. The frequency converter according to claim 3, characterized in that, The N-parallel conductive sheet (301), P-parallel conductive sheet (302) and O-parallel conductive sheet (303) are stacked and isolated from each other by a first insulating sheet (304) and a second insulating sheet (305), respectively. The N parallel port (311), P parallel port (312) and O parallel port (313) are arranged to avoid each other in the stacking direction, and the first insulating sheet (304) and the second insulating sheet (305) are respectively provided with corresponding first insulating avoidance hole (3041) and second insulating avoidance hole (3051).

5. The frequency converter according to claim 4, characterized in that, The unit connector (3) further includes: a third insulating sheet (306) disposed at the top of the stacking direction and a fourth insulating sheet (307) disposed at the bottom of the stacking direction. The third insulating sheet (306) is provided with a third insulating clearance hole (3061) to avoid the N parallel port (311), P parallel port (312) and O parallel port (313).

6. The frequency converter according to claim 5, characterized in that, At least one of the N-parallel conductive sheet (301), P-parallel conductive sheet (302) and O-parallel conductive sheet (303) is a rigid structure; Alternatively, at least one of the first insulating sheet (304), the second insulating sheet (305), the third insulating sheet (306), and the fourth insulating sheet (307) may be a rigid structure.

7. The frequency converter according to claim 6, characterized in that, The N-parallel conductive sheet (301), P-parallel conductive sheet (302) and O-parallel conductive sheet (303) have a U-shaped cross-section in the width direction.

8. The frequency converter according to claim 2, characterized in that, The unit module (1) includes: a base (101), a power module (102), a power module driver board (103), and a capacitor (104) sequentially disposed on the base (101). The power module (102), the power module driver board (103), and the capacitor (104) are electrically connected.

9. The frequency converter according to claim 8, characterized in that, A handle (1042) is provided on the outer shell (1041) of the capacitor (104).

10. The frequency converter according to claim 1, characterized in that, The unit module (1) is an inverter unit module, or a rectifier unit module, or a filter unit module.

Images