Current regulating device and cubicle system

Abstract

The application belongs to the technical field of electrical equipment, and particularly relates to a current regulating device and a centrally installed cabinet system. The current regulating device comprises: a first resistor body and a second resistor body which are arranged in parallel and are electrically insulated, one end of the first resistor body is provided with a first fixed connection end for being connected with an external first conductor, and one end of the second resistor body is provided with a second fixed connection end for being connected with an external second conductor; a sliding electric connection component, opposite ends of the sliding electric connection component are respectively in sliding electric contact with the first resistor body and the second resistor body, and the sliding electric connection component can move along the length direction of the first resistor body and the second resistor body; wherein, the movement of the sliding electric connection component is used for regulating the access resistance value between the first fixed connection end and the second fixed connection end. The application can realize accurate current shunt regulation of the centrally installed cabinet which operates in parallel at a lower cost and higher reliability, so as to meet strict temperature rise test requirements.

Description

Technical Field

[0001] This application belongs to the field of electrical equipment technology, specifically relating to a current regulating device and a central switchgear system. Background Technology

[0002] Currently, when conducting temperature rise tests on multiple parallel-connected intermediate frequency switchgear units, a common method is to connect a large-value sliding resistor in series in the circuit to achieve current distribution. This method controls the current shunting by adjusting the resistance value of the sliding resistor.

[0003] However, this scheme, which uses a series high-power sliding resistor, has the problems of high cost of the whole device and the sliding resistor being prone to overheating and burning during high current tests, resulting in high test costs and insufficient reliability. Utility Model Content

[0004] The purpose of this application is to provide a current regulating device and a central switchgear system that can achieve precise current shunting regulation of central switchgear operating in parallel with lower cost and higher reliability, thereby meeting the stringent temperature rise test requirements.

[0005] The first aspect of this application provides a current regulating device, comprising: a first resistive element and a second resistive element arranged in parallel and electrically insulated from each other, wherein one end of the first resistive element is provided with a first fixed connection end for connecting to an external first conductor, and one end of the second resistive element is provided with a second fixed connection end for connecting to an external second conductor; and a sliding electrical connection component, wherein the sliding electrical connection component makes sliding electrical contact with the first resistive element and the second resistive element at opposite ends, and is movable along the length direction of the first resistive element and the second resistive element; wherein the movement of the sliding electrical connection component is used to adjust the connection resistance value between the first fixed connection end and the second fixed connection end.

[0006] In one exemplary embodiment of this application, the first resistor and the second resistor are provided with guide structures extending along their length direction, and the sliding electrical connection component is slidably mounted on the guide structures.

[0007] In one exemplary embodiment of this application, the sliding electrical connection component is a conductive shorting block.

[0008] In one exemplary embodiment of this application, the first resistor and the second resistor are sheet resistors.

[0009] In one exemplary embodiment of this application, both the first fixed connection end and the second fixed connection end are connection holes formed at the ends of the resistor.

[0010] A second aspect of this application provides a central switchgear system, comprising: an incoming line cabinet and at least three feeder cabinets arranged in parallel; three sets of main bus pairs, each set of main bus pairs including a first main bus segment and a second main bus segment electrically spaced from each other; and three current regulating devices as described in any one of the preceding claims, each current regulating device corresponding to a set of main bus pairs, the first fixed connection terminal of each current regulating device being electrically connected to the first main bus segment of a set of main bus pairs, and the second fixed connection terminal being electrically connected to the second main bus segment of the same set of main bus pairs, so as to be connected in parallel with the feeder cabinets, forming an adjustable impedance branch between the first main bus segment and the second main bus segment.

[0011] In another exemplary embodiment of this application, the at least three feeder cabinets have the same electrical configuration.

[0012] In another exemplary embodiment of this application, by adjusting the access resistance value of the current regulating device, the current flowing through a feeder cabinet close to the incoming line cabinet can be adjusted to a rated operating current of 1250A.

[0013] In another exemplary embodiment of this application, the access resistance value of the current regulating device is adjusted to 300 μΩ.

[0014] In another exemplary embodiment of this application, when the access resistance value of the current regulating device is adjusted to 300μΩ, the displacement distance of the sliding electrical connection component is 222mm.

[0015] The current regulating device and central switchgear system proposed in this application have at least the following beneficial effects: This application employs a current regulating device composed of a first and second resistive element arranged in parallel and electrically insulated configuration, and a sliding electrical connection component. This device is integrated into a centrally located cabinet system comprising an incoming line cabinet, a feeder cabinet, and three main bus pairs, with one device corresponding to one set of main bus pairs. The two fixed connection terminals of this device are directly connected in parallel to the two sections of a set of main bus pairs, thus forming a continuously adjustable shunt branch in parallel with the feeder cabinet. This structure eliminates the need for traditional, expensive, and easily damaged high-power series resistors for shunt regulation. The shunt ratio can be changed flexibly and cost-effectively simply by adjusting the position of the sliding component on the dual resistive elements. Simultaneously, the direct parallel connection of the device to the bus pairs simplifies system integration, reduces overall complexity and cost, and improves the reliability and practicality of the temperature rise test system.

[0016] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0017] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0019] Figure 1 A schematic diagram of the connection between the current regulating device and the main bus provided in the embodiment of this application is shown.

[0020] Figure 2 A schematic diagram of the structure of the first resistor or the second resistor provided in the embodiments of this application is shown.

[0021] Figure 3 A side view of the structure of the first resistor or the second resistor provided in the embodiments of this application is shown.

[0022] Figure 4 A schematic diagram of the structure of the central cabinet system provided in an embodiment of this application is shown.

[0023] Figure 5 The circuit diagram of each feeder cabinet without a current regulating device is shown in the embodiment of this application.

[0024] Figure 6 It shows Figure 5 The equivalent circuit diagram is shown in the figure.

[0025] Figure 7 The circuit diagram of each feeder cabinet with a current regulating device provided in the embodiment of this application is shown.

[0026] Figure 8 It shows Figure 7 The equivalent circuit diagram is shown in the figure.

[0027] Figure 9 A circuit diagram illustrating the current regulating device installed in each feeder cabinet, as provided in related technologies, is shown.

[0028] Explanation of reference numerals in the attached figures: 10. Current regulating device; 11. First resistor; 12. Second resistor; 110. First fixed connection end; 111. Second fixed connection end; 13. Sliding electrical connection component; 14. Guide structure; 20. Central cabinet system; 21. Main bus pair; 210. First main bus segment; 211. Second main bus segment; T11. Incoming line cabinet; T01. First feeder cabinet; T02. Second feeder cabinet; T03. Third feeder cabinet. Detailed Implementation

[0029] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0030] In this application, 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.

[0031] In this application, unless otherwise expressly specified and limited, the terms "assembly," "connection," etc., should be interpreted broadly. For example, they can refer to a fixed 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.

[0032] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0033] See Figures 1 to 3As shown, this application embodiment provides a current regulating device 10. The current regulating device 10 may include a first resistive element 11 and a second resistive element 12 arranged in parallel and electrically isolated. In this embodiment, the two resistive elements may be resistive sheets made of 304 stainless steel, with specifications of a long strip-shaped structure of 400mm in length, 3mm in thickness, and 90mm in width. 304 stainless steel has an Ω·mm² content of approximately 0.73 Ω·mm². 2 With a resistivity of / m, high strength, and good thermal stability (withstanding temperatures up to 870℃), it can meet the working requirements at the expected temperature (not exceeding 200℃) in the temperature rise test. Each resistor has a connection hole machined at one end, which respectively constitutes the first fixed connection end 110 and the second fixed connection end 111, used to achieve a reliable electrical connection with an external conductor through fasteners such as bolts.

[0034] Understandably, in addition to 304 stainless steel sheets, the resistive element can also be made of other alloy materials with suitable resistivity and thermal stability (such as nickel-chromium alloys). Its shape can also be a circular resistance rod or other conductive material with a regular cross-sectional shape.

[0035] In some embodiments, see Figure 1 As shown, to achieve continuous adjustment of the resistance value, the device includes a sliding electrical connection component 13. This sliding electrical connection component 13 can be a conductive shorting bar. The first resistor 11 and the second resistor 12 can be provided with guide structures 14 (e.g., grooves or rails) extending along their length. The shorting bar can be slidably mounted on the guide structure 14 via an adapter structure (e.g., a slider or a snap-fit), ensuring smooth movement and maintaining good, stable electrical contact with the resistor surfaces. The opposite ends of the shorting bar are in sliding contact with the conductive surfaces of the first resistor 11 and the second resistor 12, respectively.

[0036] For example, see Figure 2 As shown, the first resistor 11 and the second resistor 12 are each provided with two parallel sliding grooves or guide rails 14, forming a double-rail guide structure 14. The two ends of the shorting bar simultaneously engage with the two sliding grooves or guide rails through their adapter structures, achieving dual positioning and constraint. This double-rail guide design ensures that the shorting bar maintains a perpendicular relationship to the surface of the resistor during sliding, effectively reducing lateral offset or torsion, thereby achieving an extremely smooth movement feel and uniform, stable, and low-resistance electrical contact with the surface of the resistor.

[0037] Furthermore, by manually moving the shorting bar along the length of the resistor, the total path length of the current flowing from the first fixed connection terminal 110 through the first resistor 11, through the shorting bar, and then through the second resistor 12 to the second fixed connection terminal 111 can be continuously changed, thereby precisely adjusting the connection resistance value between the first fixed connection terminal 110 and the second fixed connection terminal 111. This bridge structure with dual resistors and sliding shorting, combined with a dual-rail guide system, constitutes a low-cost, intuitively adjustable linear variable resistor.

[0038] It should be noted that the drive of the sliding electrical connection component 13 (short circuit bar) is not limited to manual operation. An insulated handle can be added for easy operation, or a stepper motor or other drive mechanism can be integrated to achieve remote or automatic adjustment under specific requirements.

[0039] See Figure 4 As shown, this application embodiment also provides a central switchgear system 20 using the aforementioned current regulating device 10, specifically designed for simulating temperature rise tests under actual operating conditions. The system may include: one incoming line cabinet T11 and at least three feeder cabinets connected in parallel. In some embodiments, the central switchgear system 20 may employ three feeder cabinets with identical electrical configurations: a first feeder cabinet T01, a second feeder cabinet T02, and a third feeder cabinet T03, to simulate equal load conditions. The central switchgear system 20 is equipped with three sets of main busbar pairs 21, corresponding to phases A, B, and C respectively. Each set of main busbar pairs 21 includes a first main busbar segment 210 and a second main busbar segment 211 electrically separated from each other.

[0040] It is worth mentioning that in some other embodiments, the central cabinet system 20 can also be applied to test scenarios with more or fewer feeder cabinets connected in parallel, simply by configuring the current regulating device 10 and adjusting the calculation parameters accordingly.

[0041] In some embodiments, the central distribution cabinet system 20 integrates three current regulating devices 10 as described above, with each current regulating device 10 corresponding to a set (one phase) of main bus pairs 21. For each phase, such as phase A, the first fixed connection terminal 110 of the corresponding current regulating device 10 is electrically connected to the first main bus segment 210 in the phase A main bus pair 21, and its second fixed connection terminal 111 is electrically connected to the second main bus segment 211 in the same main bus pair 21. This connection method allows the current regulating device 10, together with all the parallel feeder cabinets, to be connected in parallel between the first main bus segment 210 and the second main bus segment 211, thereby forming an impedance-adjustable shunt branch.

[0042] It should be noted that, in addition to using bolt-fixed connection holes, the connection between the first fixed connection end 110 and the first main busbar segment 210, and between the second fixed connection end 111 and the second main busbar segment 211, can also employ other reliable electrical connection methods such as crimp terminals or welding. The guide structure 14 can also be an independent guide rail, rather than being directly machined onto the resistor element.

[0043] The following is a brief introduction to the working principle and test method: The working principle of the central switchgear system 20 in this application is based on the current division law of parallel circuits. Total current I A The current flows from the incoming line cabinet T11 into the common busbar, and then into the parallel feeder cabinet branches (equivalent resistances R1, R2, R3 respectively) and the current regulating device 10 branch (equivalent resistance R). 调 The allocation is made between ).

[0044] See Figure 5 and Figure 6 As shown, when the sliding resistor is not connected, the current shunt formula is: ; ; .

[0045] See Figure 7 and Figure 8 As shown, when a sliding resistor (resistance value R) is connected... 调 When ), the diversion formula becomes: ; ; ; ; By adjusting R 调 (i.e., the shorting bar on the moving current regulating device 10) can change the distribution ratio of the current in each branch.

[0046] The specific experimental steps are as follows: The first step is to measure the basic resistance: Before the test, first measure the loop resistance of the three phases A, B and C of each feeder cabinet (T01, T02, T03) (as shown in Table 1).

[0047] Table 1

[0048] The second step is calculation and preliminary verification: Based on the parallel formula, calculate the theoretical current shunt value of each cabinet after the total current (e.g., 3600A) is applied when the current regulating device 10 is not connected (or the regulating device is placed in a certain position). Compare with the actual measured values ​​(e.g., Table 2). If there is a deviation, the influence of the main busbar's own resistance (e.g., approximately 20μΩ for T01 to T02 and approximately 40μΩ for T01 to T03 in Table 3) needs to be considered, and the calculation model needs to be corrected.

[0049] Table 2

[0050] Table 3

[0051] The third step is adjustment and target setting: Since the circuit resistance of feeder cabinets farther from the incoming line cabinet T11 is larger and the current they receive is smaller, the test usually aims to ensure that the current of the feeder cabinet closest to the incoming line cabinet T11 reaches its rated value (e.g., 1250A). According to the formula, to achieve this target, the connection resistance value R of the current regulating device 10 should be... 调 It needs to be adjusted to 300μΩ.

[0052] Step 4, Adjustment: For a 304 stainless steel resistance sheet with a total length of 400mm and dimensions of 3 (thickness) × 90 (width) mm, adjust according to the formula... Coco calculated that when At that time, the adjustment length L of the shorting bar is 222mm. In actual operation, fine-tuning is performed based on the calculated value until the target feeder cabinet current stabilizes at 1250A.

[0053] The fifth step is to conduct a temperature rise test: After the target current distribution is achieved, a long-term temperature rise test can be carried out to verify the temperature rise performance of each cabinet under simulated actual current distribution conditions.

[0054] As can be seen from the above implementation process, the current regulating device 10 and the central cabinet system 20 of this application achieve low-cost and convenient adjustment of the parallel branch impedance through a simple mechanical sliding structure of dual resistors and shorting bars. Compared with the related technologies that use series high-power sliding resistors (such as...), this approach is more efficient. Figure 9 As shown in the figure, this application has a lower cost (e.g., a cost ratio of up to 1:2200), a robust and reliable structure, and is easy to install, effectively reducing the problems of high cost and insufficient reliability of existing technologies. It is especially suitable for temperature rise test occasions where cost is sensitive and accuracy requirements are relatively relaxed.

[0055] In the description of this specification, references to terms such as "some embodiments," "exemplarily," 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 do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0056] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application. Therefore, any changes or modifications made in accordance with the claims and description of this application should fall within the scope of this patent application.

Claims

1. A current regulating device, characterized in that, include: A first resistor and a second resistor are arranged in parallel and electrically insulated manner. One end of the first resistor is provided with a first fixed connection end for connecting to an external first conductor, and one end of the second resistor is provided with a second fixed connection end for connecting to an external second conductor. A sliding electrical connection component, wherein the opposite ends of the sliding electrical connection component are in sliding electrical contact with the first resistor and the second resistor respectively, and the sliding electrical connection component is capable of moving along the length direction of the first resistor and the second resistor; The movement of the sliding electrical connection component is used to adjust the connection resistance value between the first fixed connection end and the second fixed connection end.

2. The current regulating device according to claim 1, characterized in that, The first resistor and the second resistor are provided with guide structures extending along their length direction, and the sliding electrical connection component is slidably mounted on the guide structures.

3. The current regulating device according to claim 1 or 2, characterized in that, The sliding electrical connection component is a conductive shorting block.

4. The current regulating device according to claim 1 or 2, characterized in that, The first and second resistors are sheet resistors.

5. The current regulating device according to claim 1 or 2, characterized in that, Both the first fixed connection end and the second fixed connection end are connection holes formed at the end of the resistor element.

6. A central control cabinet system, characterized in that, include: The incoming line cabinet and at least three feeder cabinets connected in parallel; Three sets of main busbar pairs, each set of main busbar pairs includes a first main busbar segment and a second main busbar segment that are electrically separated from each other; as well as The three current regulating devices as described in any one of claims 1 to 5, wherein each current regulating device corresponds to a set of main bus pairs, the first fixed connection terminal of each current regulating device is electrically connected to the first main bus segment of the set of main bus pairs, and the second fixed connection terminal is electrically connected to the second main bus segment of the same set of main bus pairs, so as to be connected in parallel with the feeder cabinet, forming an adjustable impedance branch between the first main bus segment and the second main bus segment.

7. The central control cabinet system according to claim 6, characterized in that, The at least three feeder cabinets have the same electrical configuration.

8. The central control cabinet system according to claim 6 or 7, characterized in that, By adjusting the input resistance value of the current regulating device, the current flowing through a feeder cabinet near the incoming line cabinet can be adjusted to a rated operating current of 1250A.

9. The central control cabinet system according to claim 8, characterized in that, The input resistance of the current regulating device is adjusted to 300μΩ.

10. The central control cabinet system according to claim 9, characterized in that, When the resistance value of the current regulating device is adjusted to 300μΩ, the displacement distance of the sliding electrical connection component is 222mm.

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