A power cabinet current sharing method and system

Abstract

The application discloses a power cabinet current sharing method and system, which comprises the following steps: arranging or bus of the field excitation variable AC side in a symmetrical manner, and sorting and screening thyristors in the power cabinet; in the steady state operation condition, the trigger signal is adjusted according to the detected current size of each power cabinet branch, so that the parallel branch current is balanced; in the dynamic operation condition, the corresponding trigger signal offset angle value of the corresponding current value is found by using the look-up table method through the adjusted historical data, the trigger signal offset angle value is adjusted, and the phase-shifting angle of the trigger angle of each phase is automatically matched by using the look-up table method, so that the fast dynamic current sharing is realized; the method provided by the application fundamentally reduces the current sharing factors, and the trigger signal is adjusted according to the branch current size, so that the trigger angle offset can be quickly changed, the current rapid change is adapted, and the intelligent current sharing in a true sense is realized.

Description

Technical Field

[0001] This invention relates to the field of power system stability and control technology, specifically to a power cabinet current sharing method and system. Background Technology

[0002] The parameter used to measure the current balance of each rectifier cabinet is called the current sharing coefficient, and the standard requires the current sharing coefficient to reach 0.85 or higher. This coefficient serves as the design basis for the rated output current of the rectifier bridge in the excitation system. If the current sharing coefficient of the excitation system does not meet this requirement, and the system is in a near-full load operating state for a long time, rectifier cabinets with high current will experience abnormal phenomena such as thyristor aging and fast-blow fuse failure, thereby affecting the service life of components and reducing the mean time between failures (MTBF) of the system.

[0003] Current current sharing methods are mostly natural and intelligent. Natural current sharing is related to the selection and arrangement of thyristor parameters and the laying of AC / DC cables during the design phase. Once installed, it cannot be modified and lacks flexibility. Intelligent current sharing achieves current sharing between cabinets by dynamically changing the trigger time of thyristors. This method can achieve steady-state current sharing, but in the dynamic process, due to the limitation of the adjustment speed of the current sharing device (in order not to affect the dynamic performance of the main voltage and current control loop, the adjustment speed is generally about 10 times slower than the main control loop), the dynamic compensation angle cannot be calculated quickly, which may lead to the deterioration of current sharing. Sometimes it may be more serious than not using intelligent current sharing measures, resulting in the overload and damage of some thyristors, posing a major hidden danger to the excitation system. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the above-mentioned problems, the present invention is proposed.

[0006] A first aspect of this invention provides a power cabinet current sharing method, comprising: symmetrically designing the cable arrangement or busbar on the AC side of the field excitation transformer, and sorting and screening the thyristors in the power cabinet; under steady-state operation, adjusting the trigger signal according to the detected current magnitude of each power cabinet branch to achieve current balance in parallel branches; under dynamic operation, using historical data of the adjustment to find the trigger signal offset angle value corresponding to the current value through a lookup table method, adjusting the trigger signal offset angle value, and then automatically matching the phase shift angle of the trigger angle of each phase using a lookup table method to achieve rapid dynamic current sharing.

[0007] As a preferred embodiment of the power cabinet current sharing method described in this invention, the cable layout or busbars on the AC side of the field excitation transformer are designed symmetrically during the design phase to make the AC side impedances as equal as possible.

[0008] As a preferred embodiment of the power cabinet current sharing method described in this invention, the step of sorting and screening the thyristors in the power cabinet includes:

[0009] Based on the actual parameters of each thyristor in the power cabinet, the on-state voltage drop V T and slope resistance R T Sort the thyristors from smallest to largest;

[0010] Then, the impedance of each thyristor's corresponding bridge arm is determined by the AC input position, the installation position of the power cabinet, and the position of the thyristor. The thyristors are then sorted according to their impedance. Finally, the thyristors with larger impedance and smaller on-state voltage drop are configured.

[0011] As a preferred embodiment of the power cabinet current sharing method described in this invention, the step of adjusting the trigger signal includes:

[0012] Under steady-state operation, the branch current of each power cabinet is detected, and the trigger signal is adjusted according to the detected branch current of each power cabinet.

[0013] By adjusting the trigger signal of the circuit, the branch with smaller current is triggered earlier, and the branch with larger current is triggered later, thereby achieving current balancing of parallel branches.

[0014] As a preferred embodiment of the power cabinet current sharing method described in this invention, the step of using a lookup table to find the trigger signal offset angle value corresponding to the current value includes:

[0015] In dynamic operation, the angle of the trigger pulse issued by the regulator is automatically compensated using a lookup table method based on the historical data of the adjustment.

[0016] When the current value of each power cabinet reaches the current value I in the current interval table i At that time, the trigger angle offset Δα corresponding to the current value of each power cabinet is read. Ii and the trigger angle offset Δα Ii Implement dynamic current sharing by writing into the FPGA.

[0017] As a preferred embodiment of the power cabinet current sharing method described in this invention, the calculation of the relationship between the excitation voltage and the secondary voltage of the excitation transformer includes,

[0018] U di =1.35U i cos(α+ΔαIi )

[0019] Among them, U di U represents the excitation voltage. i Δα represents the secondary voltage of the excitation transformer, α represents the trigger angle calculated by the current excitation regulator, and Δα represents the trigger angle. Ii Indicating the use of lookup tables, I is in the table. i The trigger angle offset corresponding to the current value.

[0020] As a preferred embodiment of the power cabinet current sharing method described in this invention, the phase shift angle for automatically matching the trigger angle of each phase using a lookup table interpolation method includes:

[0021] To further consider the impact of the secondary voltage change of the excitation transformer on the trigger signal, a lookup table interpolation method is used to automatically match the phase shift angle of the trigger angle of each phase to achieve current sharing.

[0022] The relationship between the excitation voltage and the secondary voltage of the excitation transformer is calculated as follows:

[0023] U dij =1.35U i cos(α+Δα Ii +Δα uj )

[0024] Among them, U dij This represents the excitation voltage when using the lookup table interpolation method, Δα. uj This indicates that U in the table is obtained through lookup interpolation. j The trigger angle offset corresponding to the voltage value.

[0025] A second aspect of the present invention provides a power cabinet current sharing system, comprising:

[0026] The design and screening unit is used to symmetrically design the cable layout or busbars on the AC side of the field excitation transformer and to sort and screen the thyristors in the power cabinet.

[0027] The steady-state operation unit is used to adjust the trigger signal according to the detected current of each power cabinet branch under steady-state operation conditions, so as to achieve current balance of parallel branches;

[0028] The dynamic operation unit is used to find the trigger signal offset angle value corresponding to the corresponding current value by using a lookup table method based on the historical data of the adjustment under dynamic operation, and adjust the trigger signal offset angle value. Then, it uses a lookup table method to automatically match the phase shift angle of the trigger angle of each phase to achieve rapid dynamic current sharing.

[0029] A third aspect of the present invention provides an apparatus, the apparatus comprising,

[0030] processor;

[0031] Memory used to store processor-executable instructions;

[0032] The processor is configured to invoke instructions stored in the memory to execute the method described in any embodiment of the present invention.

[0033] A fourth aspect of the present invention provides a computer-readable storage medium having stored thereon computer program instructions, including:

[0034] When the computer program instructions are executed by the processor, they implement the method as described in any embodiment of the present invention.

[0035] The beneficial effects of this invention are as follows: This invention provides a power cabinet current sharing method and system. From the design stage, by selecting the parameters of the thyristors and arranging the rectifier bridge, the factors of uneven current are fundamentally reduced. On this basis, the trigger signal is adjusted according to the magnitude of the branch current. In dynamic situations, the trigger angle offset can be quickly changed to adapt to rapid current changes, realizing true intelligent current sharing (steady-state and dynamic rapid current sharing). It can effectively avoid the reduction of thyristor device life caused by the inrush current generated by dynamic uneven current. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0037] Figure 1 A flowchart of a power cabinet current sharing method and system provided by the present invention;

[0038] Figure 2 The present invention provides a lookup table calculation flowchart for a power cabinet current sharing method and system. Detailed Implementation

[0039] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0040] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0041] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0042] This invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0043] Furthermore, in the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for 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 the invention. In addition, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] Unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" in this invention should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; similarly, they can refer to mechanical connections, electrical connections, or direct connections, or indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0045] Example 1

[0046] Reference Figures 1-2 As one embodiment of the present invention, a power cabinet current sharing method is provided, comprising:

[0047] S1: Design the cable layout or busbar on the AC side of the field excitation transformer symmetrically to make the AC side impedance as equal as possible.

[0048] S2: During the design phase, thyristors are sorted and screened, with the sorting aiming to ensure good consistency in key parameters among thyristors operating in parallel, and basic thyristor parameters matched with impedance. It should be noted that:

[0049] Based on the actual parameters of each thyristor, the on-state voltage drop V T and slope resistance R T Sort the thyristors from smallest to largest;

[0050] Then, by determining the impedance of the corresponding bridge arm of each thyristor based on the AC input line location, the installation location of the power cabinet, and the location of the thyristors, the thyristors are sorted according to their impedance. Thyristors with larger impedance are configured with smaller on-state voltage drop in actual parameters.

[0051] S3: Under steady-state operation, the trigger signal is adjusted according to the detected current magnitude of each power cabinet branch to achieve current balancing in parallel branches. It should be noted that:

[0052] Under steady-state operation, the branch current of each power cabinet is detected. Since the power cabinets are connected in parallel, the voltage applied to the rectifier bridge is the same. When the impedance is greater, the current is smaller.

[0053] The trigger signal is adjusted according to the current of each power cabinet branch. By adjusting the trigger signal of the circuit, the smaller current is triggered earlier and the larger current is triggered later. In other words, the current of each power cabinet is adjusted to make the current basically equal, thereby improving the current sharing effect.

[0054] S4: Under dynamic operation, by using historical data for adjustment, a lookup table method is employed to find the trigger signal offset angle value corresponding to the current value, and this trigger signal offset angle value is written into the FPGA to achieve dynamic current sharing. It should be noted that:

[0055] Under dynamic operation, the trigger pulse angle issued by the regulator is automatically compensated using a lookup table method based on historical data, enabling rapid response to current changes. The principle of the lookup table method is to set up a current interval table, where each current entry corresponds to a trigger angle offset, and the current interval can be freely set.

[0056] When the current value of each power cabinet reaches the current value I in the table i At that time, read the trigger angle offset Δα corresponding to the current value of each power cabinet. Ii and will trigger angle offset Δα Ii Implement dynamic current sharing by writing it into the FPGA;

[0057] It should be noted that the calculation of the relationship between the excitation voltage and the secondary voltage of the excitation transformer includes,

[0058] U di =1.35U i cos(α+Δα Ii )

[0059] Among them, U di U represents the excitation voltage. i Δα represents the secondary voltage of the excitation transformer, α represents the trigger angle calculated by the current excitation regulator, and Δα represents the trigger angle. Ii Indicating the use of lookup tables, I is in the table. i The trigger angle offset corresponding to the current value is obtained by interpolation for offset angles not corresponding to the current in the table.

[0060] S5: Automatically matches the phase shift angle of each phase's trigger angle using a lookup table interpolation method. It should be noted that:

[0061] like Figure 2 As shown, further considering the influence of the secondary voltage change of the excitation transformer on the trigger signal, a lookup table interpolation method is used to automatically match the phase shift angle of the trigger angle of each phase to achieve current sharing. The calculated relationship between the excitation voltage and the secondary voltage of the excitation transformer is then expressed as:

[0062] U dij =1.35U i cos(α+Δα Ii +Δα uj )

[0063] Among them, U dij This represents the excitation voltage when using the lookup table interpolation method, Δα. uj This indicates that U in the table is obtained through lookup interpolation. j The offset of the trigger angle corresponding to the voltage value is obtained by interpolation for the offset angle that is not on the corresponding current in the table.

[0064] It should be noted that the present invention provides a power cabinet current sharing method and system. From the design stage, by selecting the parameters of the thyristors and arranging the rectifier bridge, the factors of current imbalance are fundamentally reduced. On this basis, the trigger signal is adjusted according to the magnitude of the branch current. In dynamic situations, the trigger angle offset can be quickly changed to adapt to rapid current changes, realizing true intelligent current sharing (steady-state and dynamic rapid current sharing). It can effectively avoid the reduction of thyristor device life caused by the inrush current generated by dynamic current imbalance.

[0065] The second aspect disclosed in this invention,

[0066] A power cabinet current sharing system is provided, comprising:

[0067] The design and screening unit is used to symmetrically design the cable layout or busbars on the AC side of the field excitation transformer and to sort and screen the thyristors in the power cabinet.

[0068] The steady-state operation unit is used to adjust the trigger signal according to the detected current of each power cabinet branch under steady-state operation conditions, so as to achieve current balance of parallel branches;

[0069] The dynamic operation unit is used to find the trigger signal offset angle value corresponding to the current value by looking up the historical data in dynamic operation, adjust the trigger signal offset angle value, and then automatically match the phase shift angle of the trigger angle of each phase by looking up the table to achieve rapid dynamic current sharing.

[0070] The third aspect disclosed in this invention,

[0071] A device is provided, comprising:

[0072] processor;

[0073] Memory used to store processor-executable instructions;

[0074] The processor is configured to invoke instructions stored in memory to execute any of the aforementioned methods.

[0075] The fourth aspect disclosed in this invention,

[0076] A computer-readable storage medium is provided, having stored thereon computer program instructions, including:

[0077] A method by which computer program instructions are executed by a processor to implement any of the foregoing.

[0078] The present invention may be a method, apparatus, system and / or computer program product, and the computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for performing various aspects of the present invention.

[0079] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0080] Example 2

[0081] This embodiment differs from the first embodiment in that it provides a verification test of a power cabinet current sharing method and system to verify and explain the technical effects used in this method.

[0082] Based on the symmetrical design, all thyristors that can participate in the sorting are determined according to the on-state voltage drop V. T The thyristors are sorted from largest to smallest as follows: V1, V2, V3, ... . The 6n thyristors with the closest parameters are selected for the same project, where n represents the number of parallel bridge arms. In this embodiment, a certain unit has 4 power cabinets, and the AC line is connected between cabinets 2 and 3. Therefore, the impedances of cabinets 2 and 3 are approximately equal and less than the impedances of cabinets 1 and 4, and the impedances of cabinets 1 and 4 are approximately equal. Current sharing requires that the current flowing through the same bridge arm in different cabinets be equal. Therefore, the thyristor parameters of the same bridge arm should be as consistent as possible, that is, the parameters of the thyristors in the +A bridge arm should be as consistent as possible. Therefore, during the selection, the four thyristors with continuous on-state voltage drops, V1, V2, V3, and V4, are selected first. The thyristors with larger parameters are placed in cabinets 2 and 3 with smaller impedances. The final thyristor sorting is shown in Table 1.

[0083] Table 1: Thyristor screening and sorting diagram.

[0084] 1 container V1 V5 V9 V13 V17 V21 2 containers V3 V7 V11 V15 V19 V23 3 cabinets V4 V8 V12 V16 V20 V24 4 cabinets V2 V6 V10 V14 V18 V22

[0085] Referring to Table 2, based on the test data under steady-state operation, read the current value I when each power cabinet reaches the current value I in the table. i The trigger angle is recorded. For currents larger than the experimental data, the trigger angle is calculated using simulation. In this embodiment, the rated excitation current is set to 4000A, with 4 power cabinets. Each cabinet is rated at approximately 1000A. Table I1 is set to 800A, I2 to 1000A, I3 to 1200A, and so on, up to twice the rated excitation current of 2000A. However, the actual field test will not exceed the rated current. Therefore, starting from I3, the setting needs to be based on simulation calculations. Once the measured section matches the simulation, extrapolation from the simulation is used. After the parameters are set, assuming the current trigger angle of the power cabinet is α1, and the current abruptly changes to I... i So, by using the table lookup method, we can find I. i The corresponding trigger angle is α1 + Δα Ii The offset is Δα Ii This offset is written to the FPGA, which takes about two running cycles, to achieve dynamic and fast current sharing.

[0086] Table 2: Schematic diagram of the lookup table method.

[0087] Triggering angle <![CDATA[α=α1+Δα I1 ]]> <![CDATA[α=α1+Δα I2 ]]> <![CDATA[α=α1+Δα I3 ]]> <![CDATA[α=α1+Δα Ii ]]>

[0088] Referring to Table 3, in order to further achieve precise current sharing, it is also necessary to consider the change of the secondary side voltage of the excitation transformer. First, referring to Table 2, according to the test data under steady-state operation, when the secondary side voltage of the excitation transformer is U1, when the current value of each power cabinet reaches the current value I in the table i , record the corresponding firing angle; when the secondary side voltage of the excitation transformer is U2, when the current value of each power cabinet reaches the current value I in the table i , record the corresponding firing angle; when the secondary side voltage of the excitation transformer is U3, when the current value of each power cabinet reaches the current value I in the table i , record the corresponding firing angle; when the secondary side voltage of the excitation transformer is U j , when the current value of each power cabinet reaches the current value I in the table i , record the corresponding firing angle; for the firing angles corresponding to currents larger than the test data, they are filled in by means of simulation calculation. After the measurable section is consistent with the simulation, extrapolation is performed by simulation. After the parameters are set, it is assumed that the current secondary side voltage of the excitation transformer is U2, the firing angle of the power cabinet is α2, and the current suddenly changes to I i , then through the table lookup method, the firing angle corresponding to I i is α2+Δα Ii +Δα u2 , thus the offset is Δα Ii +Δα u2 , and this offset is written into the FPGA, which takes about 2 operation cycles, realizing dynamic and rapid current sharing.

[0089] Table 3: Schematic table of the table lookup method.

[0090]

[0091] Taking the fifth-dimensional table as an example, when the current secondary side voltage of the excitation transformer is U, and U1<U<U2, the current of the power cabinet is I, and I1<I<I2, it is found by table lookup that the value of the firing angle is in the gray area of Table 3. The interpolation method is used to calculate α=f(U,I), obtain the firing angle offset, write it into the FPGA, and output the result.

[0092] It can be seen from the above that the method provided by the present invention fundamentally reduces the factors causing uneven current sharing. On this basis, the firing signal is adjusted according to the branch current magnitude, which can quickly change the firing angle offset, adapt to rapid current changes, realize real intelligent current sharing, and avoid the service life reduction of thyristor devices caused by the impulse current generated by dynamic uneven current sharing.

[0093] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for current sharing in a power cabinet, characterized in that, include: The cable layout or busbars on the AC side of the field excitation transformer are designed symmetrically, and the thyristors in the power cabinet are sorted and screened. Under steady-state operation, the trigger signal is adjusted according to the detected current of each power cabinet branch to achieve current balance in parallel branches; Under dynamic operation, the trigger signal offset angle value corresponding to the current value is found by looking up the historical data and adjusting the trigger signal offset angle value. Then, the phase shift angle of the trigger angle of each phase is automatically matched by looking up the table to achieve dynamic current sharing. The adjustment of the trigger signal includes, Under steady-state operation, the branch current of each power cabinet is detected, and the trigger signal is adjusted according to the detected branch current of each power cabinet. By adjusting the trigger signal of the circuit, the branch with smaller current is triggered earlier, and the branch with larger current is triggered later, thereby achieving current balancing of parallel branches; The method of using a lookup table to find the trigger signal offset angle value corresponding to the current value includes... Under dynamic operation, the angle of the trigger pulse issued by the regulator is automatically compensated by looking up a table using historical data. When the current value of each power cabinet reaches the current value in the current interval table At that time, the trigger angle offset corresponding to the current value of each power cabinet is read. and the trigger angle offset Implement dynamic current sharing by writing it into the FPGA; The calculation of the relationship between the excitation voltage and the secondary voltage of the excitation transformer includes, in, Indicates the excitation voltage. This represents the secondary voltage of the excitation transformer. This indicates the trigger angle calculated by the current excitation regulator. Indicating the use of lookup tables The trigger angle offset corresponding to the current value; The phase shift angle for automatically matching the trigger angle of each phase using the lookup table interpolation method includes, To further consider the impact of the secondary voltage change of the excitation transformer on the trigger signal, a lookup table interpolation method is used to automatically match the phase shift angle of the trigger angle of each phase to achieve current sharing. The relationship between the excitation voltage and the secondary voltage of the excitation transformer is calculated as follows: in, This represents the excitation voltage when using the lookup table interpolation method. This indicates the table lookup interpolation method in the table. The trigger angle offset corresponding to the voltage value.

2. The power cabinet current sharing method as described in claim 1, characterized in that: During the design phase, the cable layout or busbars on the AC side of the field excitation transformer should be designed symmetrically to ensure that the AC side impedances are as equal as possible.

3. The power cabinet current sharing method as described in claim 2, characterized in that: The sorting and screening of thyristors in the power cabinet includes... Based on the actual on-state voltage drop of each thyristor in the power cabinet and slope resistance Sort the thyristors from smallest to largest; Then, the impedance of each thyristor's corresponding bridge arm is determined by the AC input position, the installation position of the power cabinet, and the position of the thyristor. The thyristors are then sorted according to their impedance. Finally, the thyristors with larger impedance and smaller on-state voltage drop are configured.

4. A system for implementing the power cabinet current sharing method as described in any one of claims 1 to 3, characterized in that, include: The design and screening unit is used to symmetrically design the cable layout or busbars on the AC side of the field excitation transformer and to sort and screen the thyristors in the power cabinet. The steady-state operation unit is used to adjust the trigger signal according to the detected current of each power cabinet branch under steady-state operation conditions, so as to achieve current balance of parallel branches; The dynamic operation unit is used to find the trigger signal offset angle value corresponding to the corresponding current value by looking up historical data in dynamic operation, adjust the trigger signal offset angle value, and then automatically match the phase shift angle of the trigger angle of each phase by looking up the table to achieve rapid dynamic current sharing.

5. An electronic device, characterized in that, The device includes, processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the method described in any one of claims 1 to 3.

6. A computer-readable storage medium having computer program instructions stored thereon, characterized in that, When the computer program instructions are executed by the processor, they implement the method described in any one of claims 1 to 3.

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