Adjustable inductance loop based on multi-port electric energy router and design method thereof

Abstract

The invention belongs to the technical field of alternating-current and direct-current power distribution networks, and discloses an adjustable inductance loop based on a multi-port electric energy router and a design method thereof.The adjustable inductance loop comprises two high-frequency busbars, a plurality of lifting mechanisms, ports and an electric reactor, and the distance between the two high-frequency busbars is adjusted through the lifting mechanisms; a plurality of reactors are arranged on one group of high-frequency busbars; the plurality of ports are connected through two high-frequency busbars, and a dual-active bridge is formed between any two ports; the port is formed by connecting a plurality of modules in parallel, each module comprises a supporting capacitor, an H-bridge structure and a high-frequency transformer, the supporting capacitors are connected to the two ends of the H-bridge structure in parallel, and two branches of the high-frequency transformer are connected with two half-bridge middle points of the H-bridge structure respectively. According to the invention, the loss of the high-frequency transformer can be reduced, the efficiency of the whole system is improved, and the phase-shift inductance in the power transmission process can be accurately found, so that the stability of the system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of AC and DC power distribution networks, and in particular to an adjustable inductance loop based on a multi-port power router and a design method thereof. Background Art

[0002] With the large-scale access of distributed renewable energy and the continuous increase in power load, transformer overload events have occurred frequently and the mismatch between source and load has intensified, which has seriously affected the safe operation of the power grid and caused the inability of distributed photovoltaic to be connected, generated, and operated. At present, the traditional distribution and use power grid with rigid closing and opening and weak regulation capabilities, as well as traditional switches and transformer equipment, can no longer meet the large-scale access of renewable energy. It is urgent to develop new equipment and research new systems. The flexible transformation of the traditional distribution and use power grid is urgent. The structure of highly autonomous partitions and hierarchical and grouped operation based on power routers is an important form of the new distribution system, which can effectively improve the flexible regulation capability, distributed energy consumption capability, and fault recovery capability. With the continuous development of power router technology, there are currently a variety of topology solutions. The power router with a common high-frequency AC busbar collection solution has the advantages of less power conversion, high efficiency, and low cost, and has a wide range of application scenarios. The core device of the power router is the power unit. Multiple power units are connected in series and parallel to achieve the improvement of the voltage and power level of the power router.

[0003] The power router of the common high-frequency AC bus collection solution realizes power transmission between any ports of the converter by controlling the phase shift angle between different H bridges. The current existing technology uses the leakage inductance value of the high-frequency transformer as the phase shift inductance required for power transmission. This method will bring the following problems in practical applications:

[0004] (1) For the high-frequency transformer itself, the smaller the leakage inductance value of the high-frequency transformer, the smaller its loss. In order to meet the phase-shift inductance required for power transmission, it is necessary to increase the leakage inductance of the high-frequency transformer to match the required phase-shift inductance, which increases the loss of the high-frequency transformer and thus reduces the efficiency of the entire converter.

[0005] (2) The power router of the common high-frequency AC bus collection scheme often adopts a modular integrated structure. Each port is composed of X modules, each module contains a high-frequency transformer, and the X modules are connected in parallel on the high-frequency AC bus side. The required leakage inductance value of each high-frequency transformer is X times the port leakage inductance value, that is, the phase-shift leakage inductance value required for power transmission, which increases the leakage inductance value of the high-frequency transformer in disguised form, thereby increasing the loss.

[0006] (3) The phase-shifting inductance required for power transmission between ports cannot be completely equivalent to the leakage inductance of all high-frequency transformers at the ports, but should also include the stray inductance in the loop. In low-voltage and low-power scenarios, the loop is short and the stray inductance in the loop is relatively small and can be ignored. However, in medium-voltage and high-voltage high-power scenarios, each phase of the AC port is a separate cabinet, and each port is connected through a common high-frequency bus. The loop is long, the loop inductance is large and cannot be ignored. Since the stray inductance in the loop cannot be calculated accurately, there is a certain deviation between the leakage inductance of the high-frequency transformer, the stray inductance in the loop and the phase-shifting inductance required for power transmission. The leakage inductance value of the high-frequency transformer is fixed after production and cannot be adjusted, which affects the range of transmission power.

[0007] Therefore, how to provide an adjustable inductance loop based on a multi-port power router and a design method thereof is a problem that needs to be solved urgently. Summary of the invention

[0008] The embodiment of the present invention provides an adjustable inductance loop based on a multi-port power router and a design method thereof, which can not only design the leakage inductance of the high-frequency transformer to be as small as possible, thereby reducing losses and improving overall efficiency, but also can continuously adjust the loop inductance to find the optimal phase-shift inductance value, thereby improving the stability of power transmission, so as to solve the above-mentioned technical problems in the prior art.

[0009] In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended to be a general review, nor is it intended to identify key / important components or to delineate the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0010] According to a first aspect of an embodiment of the present invention, an adjustable inductance loop based on a multi-port power router and a design method thereof are provided.

[0011] In one embodiment, the adjustable inductance circuit based on the multi-port power router includes two high-frequency busbars, several lifting mechanisms, ports and reactors, and the spacing between the two high-frequency busbars is adjusted by several lifting mechanisms, and one group of the high-frequency busbars is provided with several reactors; several ports are connected by the two high-frequency busbars, and a dual active bridge is formed between any two ports.

[0012] In one embodiment, the two high-frequency busbars have the same height and thickness, and are arranged parallel to each other along the thickness direction.

[0013] In one embodiment, the number of the lifting mechanisms is configured according to the actual length of the two high-frequency busbars, the number of the ports is greater than the number of the reactors, and reactors are provided between adjacent ports.

[0014] In one embodiment, the lifting mechanism includes an insulating screw, a fixed seat, a lifting seat and a fixed plate, and one end of the insulating screw is connected to one group of the high-frequency busbars through the fixed seat, the lifting seat is sleeved on the middle part of the insulating screw, and the lifting seat is connected to another group of the high-frequency busbars, and the other end of the insulating screw is connected to the fixed plate.

[0015] In one embodiment, the port is formed by connecting several groups of modules in parallel, each module includes a supporting capacitor, an H-bridge structure and a high-frequency transformer, the supporting capacitor is connected in parallel at both ends of the H-bridge structure, and the two branches of the high-frequency transformer are respectively connected to the middle points of the two half bridges of the H-bridge structure.

[0016] According to a second aspect of an embodiment of the present invention, a design method for an adjustable inductor loop based on a multi-port power router is provided.

[0017] In one embodiment, the design method of the adjustable inductance loop based on the multi-port power router includes:

[0018] Determine the phase shift inductance required for power transmission between ports based on the transmission power expression, and determine the shortest length and minimum spacing between two high-frequency busbars based on the number and position of ports;

[0019] The finite element analysis method is used to estimate the loop inductance value, and the maximum spacing value between the two high-frequency busbars is determined based on the loop inductance value, and the optimal spacing between the two high-frequency busbars is determined based on the maximum spacing value;

[0020] Based on the optimal spacing, adjust the length of the two high-frequency busbars or connect series reactors to ensure that the loop inductance value meets the phase-shift inductance requirements;

[0021] Adjust the distance between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is maximum, until the design requirements are met.

[0022] In one embodiment, the transmission power expression is:

[0023]

[0024] In the formula, P represents the required transmission power between ports, n represents the transformation ratio of the high-frequency transformer, U1 and U2 represent the voltages at both ends of the dual active bridge, D represents the phase shift ratio, f represents the frequency, and L represents the phase shift inductance required for power transmission between ports.

[0025] In one embodiment, the phase-shift inductance required for power transmission between the ports includes loop inductance and high-frequency transformer leakage inductance, and the loop inductance of the conductor in the loop is positively correlated with the length of the high-frequency busbar and the distance between the two high-frequency busbars.

[0026] In one embodiment, the minimum spacing between the two high-frequency busbars is equal to the minimum insulation distance between the two high-frequency busbars.

[0027] In one embodiment, the estimating the loop noise inductance value by using the finite element analysis method, determining the maximum spacing value between the two high-frequency busbars based on the loop noise inductance value, and determining the optimal spacing between the two high-frequency busbars according to the maximum spacing value includes:

[0028] According to the preset distance threshold, the distance between the two high-frequency busbars is increased in sequence, and the loop noise inductance value is estimated by the finite element analysis method until the change of the loop noise inductance value is less than the preset loop noise inductance threshold, and the maximum spacing value is obtained, and the middle spacing value of the maximum spacing is taken as the optimal spacing between the two high-frequency busbars.

[0029] In one embodiment, the preset distance threshold when the distance between two high-frequency busbars is increased sequentially is 10 mm, and the preset loop noise threshold when the change of the loop noise value is less than the preset loop noise threshold is 1%.

[0030] In one embodiment, the loop inductance value is equal to the difference between the phase-shift inductance value and the leakage inductance value of the high-frequency transformer.

[0031] In one embodiment, adjusting the length of two high-frequency busbars or connecting a series reactor based on the optimal spacing to ensure that the loop inductance value meets the phase-shift inductance requirement includes:

[0032] Estimate the inductance of the two high-frequency busbars according to the optimal spacing, and calculate the difference between the loop inductance and the phase-shift inductance. Gradually increase the length of the two high-frequency busbars. When the loop inductance is equal to the phase-shift inductance, take the current high-frequency busbar length as the optimal length. When the loop inductance is not equal to the phase-shift inductance and the high-frequency busbar length cannot be increased, then based on the shortest length of the high-frequency busbar, connect reactors in series between the two ports to meet the phase-shift inductance.

[0033] In one embodiment, adjusting the spacing between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is maximum until the design requirements are met includes:

[0034] Determine whether the power reaches the preset design value when the displacement is maximum. If it is less than the preset design value, use the lifting mechanism to reduce the distance between the two high-frequency busbars according to the preset distance until the power meets the preset design value. If it is greater than the preset design value, use the lifting mechanism to increase the distance between the two high-frequency busbars according to the preset distance until the power meets the preset design value.

[0035] In one embodiment, the lifting mechanism reduces or increases the distance between the two high-frequency busbars according to the preset distance of 10 mm.

[0036] In one embodiment, the step of adjusting the spacing between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is the maximum until the design requirements are met also includes:

[0037] Based on the optimal spacing and length between the two high-frequency busbars and the series connection of the reactors between the two ports, an adjustable inductance circuit based on a multi-port power router is designed, produced and assembled.

[0038] The technical solution provided by the embodiment of the present invention may have the following beneficial effects:

[0039] The present invention can not only reduce the loss of the high-frequency transformer and improve the efficiency of the entire system by replacing the leakage inductance of the high-frequency transformer with the loop inductance, but also accurately find the phase-shifting inductance in the power transmission process through the adjustable loop inductance, thereby improving the stability of the system.

[0040] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0042] Figure 1 is a topological structure diagram of an adjustable inductor loop based on a multi-port power router according to an exemplary embodiment;

[0043] Figure 2 is a diagram of a port topology structure in an adjustable inductance loop based on a multi-port power router according to an exemplary embodiment;

[0044] Figure 3 is a schematic diagram of a high-frequency busbar lifting mechanism in an adjustable inductance circuit based on a multi-port power router according to an exemplary embodiment;

[0045] Figure 4 The invention is a flow chart of a method for designing an adjustable inductor loop based on a multi-port power router according to an exemplary embodiment. DETAILED DESCRIPTION

[0046] The following description and accompanying drawings fully illustrate the specific embodiments of this article so that those skilled in the art can practice them. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of this article includes the entire scope of the claims, as well as all available equivalents of the claims. Herein, the terms "first", "second", etc. are only used to distinguish one element from another, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the structure, device or equipment including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also include elements inherent to such structure, device or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the structure, device or equipment including the elements. Each embodiment is described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other.

[0047] The terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. in this document indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this document and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of this document, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, it can also be the internal communication of two elements, it can be a direct connection, or it can be an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0048] As used herein, unless otherwise specified, the term "plurality" means two or more than two.

[0049] In this document, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0050] In this article, the term "and / or" is a description of the association relationship between objects, indicating that three relationships may exist. For example, A and / or B means: A or B, or, A and B.

[0051] It should be understood that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0052] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0053] Figure 1-Figure 3 An adjustable inductance loop based on a multi-port power router of the present invention is shown.

[0054] In this optional embodiment, the adjustable inductance circuit based on the multi-port power router includes two high-frequency busbars 1, several lifting mechanisms 2, ports 3 and reactors 4, and the distance between the two high-frequency busbars 1 is adjusted by several lifting mechanisms 2, and one group of the high-frequency busbars 1 is provided with several reactors 4; several ports 3 are connected through the two high-frequency busbars 1, and a dual active bridge is formed between any two ports 3.

[0055] In this optional embodiment, the two high-frequency busbars 1 have the same height and thickness, and the two high-frequency busbars 1 are arranged in parallel along the thickness direction.

[0056] In this optional embodiment, the number of the lifting mechanisms 2 is configured according to the actual length of the two high-frequency busbars 1 , the number of the ports 3 is greater than the number of the reactors 4 , and reactors 4 are provided between adjacent ports 3 .

[0057] In this optional embodiment, the lifting mechanism 2 includes an insulating screw 21, a fixed seat 22, a lifting seat 23 and a fixed plate 24, and one end of the insulating screw 21 is connected to one group of the high-frequency busbars 1 through the fixed seat 22, the lifting seat 23 is sleeved on the middle part of the insulating screw 21, and the lifting seat 23 is connected to another group of the high-frequency busbars 1, and the other end of the insulating screw 21 is connected to the fixed plate 24.

[0058] In this optional embodiment, the port 3 is composed of several groups of modules connected in parallel, each module includes a supporting capacitor C, an H-bridge structure and a high-frequency transformer T, the supporting capacitor C is connected in parallel at both ends of the H-bridge structure, and the two branches of the high-frequency transformer T are respectively connected to the middle points of the two half bridges of the H-bridge structure.

[0059] Figure 2 An embodiment of a design method of an adjustable inductance loop based on a multi-port power router of the present invention is shown.

[0060] In this optional embodiment, the design method of the adjustable inductance loop based on the multi-port power router includes:

[0061] Determine the phase shift inductance required for power transmission between ports based on the transmission power expression, and determine the shortest length and minimum spacing between two high-frequency busbars based on the number and position of ports;

[0062] The finite element analysis method is used to estimate the loop inductance value, and the maximum spacing value between the two high-frequency busbars is determined based on the loop inductance value, and the optimal spacing between the two high-frequency busbars is determined based on the maximum spacing value;

[0063] Based on the optimal spacing, adjust the length of the two high-frequency busbars or connect series reactors to ensure that the loop inductance value meets the phase-shift inductance requirements;

[0064] Adjust the distance between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is maximum, until the design requirements are met.

[0065] In this optional embodiment, the transmission power expression is:

[0066]

[0067] In the formula, P represents the required transmission power between ports, n represents the transformation ratio of the high-frequency transformer, U1 and U2 represent the voltages at both ends of the dual active bridge, D represents the phase shift ratio, f represents the frequency, and L represents the phase shift inductance required for power transmission between ports.

[0068] In this optional embodiment, the phase-shifting inductance required for power transmission between the ports includes loop inductance and high-frequency transformer leakage inductance, and the loop inductance of the conductor in the loop is positively correlated with the length of the high-frequency busbar and the distance between the two high-frequency busbars.

[0069] In this optional embodiment, the minimum spacing between the two high-frequency busbars is equal to the minimum insulation distance between the two high-frequency busbars.

[0070] In this optional embodiment, the estimating the loop noise inductance value by using the finite element analysis method, determining the maximum spacing value between the two high-frequency busbars based on the loop noise inductance value, and determining the optimal spacing between the two high-frequency busbars according to the maximum spacing value includes:

[0071] According to the preset distance threshold, the distance between the two high-frequency busbars is increased in sequence, and the loop noise inductance value is estimated by the finite element analysis method until the change of the loop noise inductance value is less than the preset loop noise inductance threshold, and the maximum spacing value is obtained, and the middle spacing value of the maximum spacing is taken as the optimal spacing between the two high-frequency busbars.

[0072] In this optional embodiment, the preset distance threshold when the distance between two high-frequency busbars is increased sequentially is 10 mm, until the preset loop noise inductance threshold when the change in the loop noise inductance value is less than the preset loop noise inductance threshold is 1%.

[0073] In this optional embodiment, the loop inductance value is equal to the difference between the phase-shift inductance value and the leakage inductance value of the high-frequency transformer.

[0074] In this optional embodiment, adjusting the length of the two high-frequency busbars or the series reactor based on the optimal spacing to ensure that the loop inductance value meets the phase shift inductance requirement includes:

[0075] Estimate the inductance of the two high-frequency busbars according to the optimal spacing, and calculate the difference between the loop inductance and the phase-shift inductance. Gradually increase the length of the two high-frequency busbars. When the loop inductance is equal to the phase-shift inductance, take the current high-frequency busbar length as the optimal length. When the loop inductance is not equal to the phase-shift inductance and the high-frequency busbar length cannot be increased, then based on the shortest length of the high-frequency busbar, connect reactors in series between the two ports to meet the phase-shift inductance.

[0076] In this optional embodiment, adjusting the spacing between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is maximum until the design requirements are met includes:

[0077] Determine whether the power reaches the preset design value when the displacement is maximum. If it is less than the preset design value, use the lifting mechanism to reduce the distance between the two high-frequency busbars according to the preset distance until the power meets the preset design value. If it is greater than the preset design value, use the lifting mechanism to increase the distance between the two high-frequency busbars according to the preset distance until the power meets the preset design value.

[0078] In this optional embodiment, the lifting mechanism reduces or increases the distance between the two high-frequency busbars according to the preset distance of 10 mm.

[0079] In this optional embodiment, the step of adjusting the spacing between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is the maximum until the design requirements are met also includes:

[0080] Based on the optimal spacing and length between the two high-frequency busbars and the series connection of the reactors between the two ports, an adjustable inductance circuit based on a multi-port power router is designed, produced and assembled.

[0081] In order to facilitate understanding of the above technical solutions of the present invention, the above technical solutions of the present invention are further described below from the perspective of architecture and principle, as follows:

[0082] An adjustable inductance circuit based on a multi-port power router includes two high-frequency busbars 1, N groups of lifting mechanisms 2, M ports 3, and M-1 reactors 4; the number N is configured according to the actual length of the two high-frequency busbars 1; and M is greater than 1. The port 3 includes Z groups of modules in parallel; the module includes: a supporting capacitor C, an H-bridge structure, and a high-frequency transformer T; the supporting capacitor C is connected in parallel at both ends of the H-bridge; the two branches of the high-frequency transformer T are respectively connected to the middle points of the two half-bridges of the H-bridge structure; the leakage inductance of the high-frequency transformer T is as small as possible; each port 3 is connected through two high-frequency busbars 1, and a dual active bridge is formed between any two ports 3; the two high-frequency busbars 1 have the same width and thickness and are arranged in parallel along the thickness direction. The lifting mechanism 2 includes an insulating screw 21, a fixing seat 22, a lifting seat 23, and a fixing plate 24; one end of the insulating screw 21 is connected to a high-frequency busbar 1 through the fixing seat 22, and the other end is connected to the fixing plate 24; the lifting seat 23 is connected to another high-frequency busbar 1; the lifting seat 23 and the insulating screw 21 can move relative to each other to achieve a change in the distance between the high-frequency busbars 1.

[0083] The design method of the adjustable inductor loop based on the multi-port power router includes: the port power transmission phase shift inductor L includes the loop inductance L s , high frequency transformer leakage inductance L m ; The leakage inductance of the high-frequency transformer is as small as possible to reduce transformer loss; The inductance of the conductor in the loop is related to the length of the high-frequency busbar and the spacing between the two high-frequency busbars; The longer the high-frequency busbar is, the greater the inductance of the conductor in the loop; The greater the spacing, the greater the loop inductance, and vice versa; In the process of designing the port adjustable inductance loop, firstly according to the formula Determine the phase shift inductance required for power transmission between ports, where P represents the required transmission power between ports, n represents the transformation ratio of the high-frequency transformer, U1 and U2 represent the voltages at both ends of the dual active bridge, D represents the phase shift ratio, f represents the frequency, and L represents the phase shift inductance required for power transmission between ports. s Equal to the phase shift inductance L minus the high frequency transformer leakage inductance L m, determine the shortest length between the two high-frequency busbars and the minimum spacing between the busbars according to the port position. The minimum spacing is equal to the minimum insulation distance between the two high-frequency busbars; the spacing between the two high-frequency busbars increases by 10mm accordingly, and the loop inductance values ​​are estimated by finite element analysis method respectively, until the change of the inductance value is less than 1%, record the maximum spacing value, and take the middle spacing value as the optimal spacing between the two high-frequency busbars; estimate the inductance value of the two high-frequency busbars at this time, calculate the difference between the inductance value and the phase-shift inductance value, and judge whether the loop inductance value and the phase-shift inductance value are equal by gradually increasing the length of the two high-frequency busbars; if they are equal, then the high-frequency busbar length is the optimal length at this time. If the high-frequency busbar length cannot be increased, the loop inductance still cannot meet the phase-shift inductance value. On the basis of the shortest length of the high-frequency busbar, a reactor is connected in series between the two ports to meet the phase-shift inductance; the adjustable circuit is designed, produced and assembled, and its loop path and high-frequency transformer leakage inductance value have been determined. According to the formula

[0084] It can be seen that through experimental tests, when the displacement is the largest, it is judged whether the power reaches the design value. If it is less than the design value, the spacing between the high-frequency busbars is reduced by a lifting mechanism according to a spacing of 10 mm, that is, the loop noise value is reduced until the power meets the design value; if it is greater than the design value, the spacing between the busbars is increased by a lifting mechanism according to a spacing of 10 mm, that is, the loop noise value is increased, until the power meets the design value.

[0085] The present invention is not limited to the structures which have been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. An adjustable inductance loop based on a multi-port power router, characterized in that: It includes two high-frequency busbars, several lifting mechanisms, ports and reactors, and the distance between the two high-frequency busbars is adjusted by several lifting mechanisms, and one group of the high-frequency busbars is provided with several reactors; several ports are connected by the two high-frequency busbars, and a dual active bridge is formed between any two ports.

2. The adjustable inductance loop based on a multi-port power router according to claim 1, characterized in that: The two high-frequency busbars have the same height and thickness, and are arranged parallel to each other along the thickness direction.

3. The adjustable inductance loop based on a multi-port power router according to claim 1, characterized in that: The number of the lifting mechanisms is configured according to the actual length of the two high-frequency busbars, the number of the ports is greater than the number of the reactors, and reactors are arranged between adjacent ports.

4. The adjustable inductance loop based on a multi-port power router according to claim 1, characterized in that: The lifting mechanism includes an insulating screw, a fixing seat, a lifting seat and a fixing plate, and one end of the insulating screw is connected to one group of the high-frequency busbars through the fixing seat, the lifting seat is sleeved on the middle part of the insulating screw, and the lifting seat is connected to another group of the high-frequency busbars, and the other end of the insulating screw is connected to the fixing plate.

5. The adjustable inductance loop based on a multi-port power router according to claim 1, characterized in that: The port is formed by connecting several groups of modules in parallel, each module includes a supporting capacitor, an H-bridge structure and a high-frequency transformer, the supporting capacitor is connected in parallel to both ends of the H-bridge structure, and the two branches of the high-frequency transformer are respectively connected to the middle points of the two half-bridges of the H-bridge structure.

6. A design method for an adjustable inductance loop based on a multi-port power router, characterized in that: include: Determine the phase shift inductance required for power transmission between ports based on the transmission power expression, and determine the shortest length and minimum spacing between two high-frequency busbars based on the number and position of ports; The finite element analysis method is used to estimate the loop inductance value, and the maximum spacing value between the two high-frequency busbars is determined based on the loop inductance value, and the optimal spacing between the two high-frequency busbars is determined based on the maximum spacing value; Based on the optimal spacing, adjust the length of the two high-frequency busbars or connect series reactors to ensure that the loop inductance value meets the phase-shift inductance requirements; Adjust the distance between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is maximum, until the design requirements are met.

7. The design method of an adjustable inductance loop based on a multi-port power router according to claim 6, characterized in that: The transmission power expression is: In the formula, P represents the required transmission power between ports, n represents the transformation ratio of the high-frequency transformer, U1 and U2 represent the voltages at both ends of the dual active bridge, D represents the phase shift ratio, f represents the frequency, and L represents the phase shift inductance required for power transmission between ports.

8. The design method of an adjustable inductance loop based on a multi-port power router according to claim 6, characterized in that: The phase shift inductance required for power transmission between the ports includes loop inductance and high-frequency transformer leakage inductance, and the loop inductance of the conductor in the loop is positively correlated with the length of the high-frequency busbar and the distance between the two high-frequency busbars.

9. The design method of an adjustable inductance loop based on a multi-port power router according to claim 6, characterized in that: The minimum spacing between two high-frequency busbars is equal to the minimum insulation distance between the two high-frequency busbars.

10. The design method of an adjustable inductance loop based on a multi-port power router according to claim 6, characterized in that: The method of estimating the loop noise inductance value by using the finite element analysis method, determining the maximum spacing value between the two high-frequency busbars based on the loop noise inductance value, and determining the optimal spacing between the two high-frequency busbars according to the maximum spacing value includes: According to the preset distance threshold, the distance between the two high-frequency busbars is increased in sequence, and the loop noise inductance value is estimated by the finite element analysis method until the change of the loop noise inductance value is less than the preset loop noise inductance threshold, and the maximum spacing value is obtained, and the middle spacing value of the maximum spacing is taken as the optimal spacing between the two high-frequency busbars.

11. The design method of an adjustable inductance loop based on a multi-port power router according to claim 10, characterized in that: The preset distance threshold when the distance between the two high-frequency busbars is increased successively is 10 mm, and the preset loop noise inductance threshold when the change of the loop noise inductance value is less than the preset loop noise inductance threshold is 1%.

12. The design method of an adjustable inductance loop based on a multi-port power router according to claim 10, characterized in that: The loop inductance value is equal to the difference between the phase shift inductance value and the leakage inductance value of the high frequency transformer.

13. The design method of an adjustable inductance loop based on a multi-port power router according to claim 6, characterized in that: The method of adjusting the length of the two high-frequency busbars or connecting a series reactor based on the optimal spacing to ensure that the loop inductance value meets the phase shift inductance requirement includes: Estimate the inductance of the two high-frequency busbars according to the optimal spacing, and calculate the difference between the loop inductance and the phase-shift inductance. Gradually increase the length of the two high-frequency busbars. When the loop inductance is equal to the phase-shift inductance, take the current high-frequency busbar length as the optimal length. When the loop inductance is not equal to the phase-shift inductance and the high-frequency busbar length cannot be increased, then based on the shortest length of the high-frequency busbar, connect reactors in series between the two ports to meet the phase-shift inductance.

14. The design method of an adjustable inductance loop based on a multi-port power router according to claim 6, characterized in that: The adjustment of the spacing between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is the maximum until the design requirements are met includes: Determine whether the power reaches the preset design value when the displacement is maximum. If it is less than the preset design value, use the lifting mechanism to reduce the distance between the two high-frequency busbars according to the preset distance until the power meets the preset design value. If it is greater than the preset design value, use the lifting mechanism to increase the distance between the two high-frequency busbars according to the preset distance until the power meets the preset design value.

15. The design method of an adjustable inductance loop based on a multi-port power router according to claim 14, characterized in that: When the lifting mechanism reduces or increases the distance between the two high-frequency busbars, the preset distance is 10 mm.

16. The design method of an adjustable inductance loop based on a multi-port power router according to claim 13, characterized in that: The step of adjusting the spacing between the two high-frequency busbars according to the test results to ensure that the power reaches the design value when the displacement is the maximum until the design requirements are met also includes: Based on the optimal spacing and length between the two high-frequency busbars and the series connection of the reactors between the two ports, an adjustable inductance circuit based on a multi-port power router is designed, produced and assembled.

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