Magnetic circuit collaborative design method for zigzag primary side multi-winding phase-shifting transformer

Abstract

The application discloses a magnetic circuit collaborative design method of a zigzag primary side multi-winding phase-shifting transformer, and comprises the following steps: according to a target phase angle and a structure constraint, a circuit basic structure is designed, that is, a multi-winding mixed connection structure of a zigzag Z11 connection of a primary side and a D1 connection of a secondary side; a physical topology structure matched with the circuit basic structure is constructed; two half windings of the zigzag primary winding are arranged in adjacent high magnetic flux areas of core columns respectively, and a main winding and a segmented voltage regulation winding of a secondary side are distributed in a multi-column mutual embedding mode; a symmetrically arranged coupling winding is introduced between the main winding and the secondary winding; and based on the physical topology structure, electrical and structural parameters are optimized, and a circuit diagram of the phase-shifting transformer is constructed. The topology and the design method have good engineering popularization value, which is suitable for various application scenarios such as flexible loop closing of a power distribution network and grid connection of a distributed power supply, and can adjust the number of secondary side multi-windings, the number of voltage regulation segments and the gear configuration according to different engineering requirements without changing the zigzag structure of the primary side.

Description

Technical Field

[0001] This invention belongs to the field of transformer topology design and electromagnetic design technology, specifically relating to a method for the coordinated design of magnetic circuits in a tortuous primary-side multi-winding phase-shifting transformer. Background Technology

[0002] With the expansion of distribution network scale and the large-scale integration of distributed power sources, power grid operation exhibits typical characteristics of multiple feeders, strong coupling, and bidirectional power flow, placing higher demands on the phase angle coordination and flexible regulation capabilities of the distribution network. In medium-voltage distribution networks, power supply lines from different substations often use different main transformer connection groups, resulting in an inherent phase angle difference in line voltage at the loop closing point. When using traditional loop closing methods, a large inrush current is generated at the moment of loop closing due to the phase angle deviation, which also forms a continuous circulating current during steady-state operation, leading to problems such as line overload, protection malfunction, and reduced system stability margin. Therefore, achieving flexible compensation of the phase angle between the two systems has become a key technical direction for improving the flexibility and reliability of the distribution network.

[0003] Existing technologies generally achieve phase angle adjustment through phase-shifting transformers with fixed phase shifts or power electronic "back-to-back" flexible interconnection systems. However, the former has a fixed and unadjustable phase angle and poor adaptability; while the latter, although possessing rapid adjustment capabilities, suffers from engineering drawbacks such as high cost, large losses, complex maintenance, and insufficient reliability. Traditional D-type or YN-type connected phase-shifting transformers typically rely on winding connection methods to obtain a fixed 30° or 60° phase difference, making it difficult to meet the continuous, controllable, and multi-level phase adjustment requirements of applications such as distributed power supply access, multi-feeder power supply coordination, and uninterrupted load transfer. Furthermore, traditional methods are mostly designed based on the potential distribution between a single main and auxiliary winding, lacking a systematic magnetic circuit-circuit structure design framework under the coordinated action of multiple windings, electromagnetic coupling, and multi-state switches. This results in significant limitations in terms of phase adjustment continuity, adjustment range, and output stability.

[0004] To address unbalanced loads and zero-sequence current issues, some engineering solutions have introduced zigzag winding structures. This structure, by splitting each phase winding into two segments, winding across columns and employing a bend in the connection, can improve the zero-sequence flux path and unbalanced operation performance without altering the fundamental equivalent phase. However, existing zigzag windings are mostly used in distribution transformers and grounding transformers, primarily targeting zero-sequence and unbalanced compensation. They have not yet been deeply integrated with multi-winding phase-shifting topologies, and lack a systematic approach for unified modeling and collaborative optimization of the zigzag primary-side magnetic circuit characteristics and the continuous phase-shifting circuit of the multi-winding secondary side.

[0005] To address the above issues, proposing multi-winding coupling-assisted adjustment mechanisms and hybrid wiring topologies has become a feasible approach. However, existing publicly available technologies generally suffer from the following shortcomings in their related designs:

[0006] (1) The limited number of windings and the single coupling method make it difficult to achieve wide-range, high-resolution continuous phase adjustment;

[0007] (2) The coupling between the main and auxiliary magnetic circuits and the adjustable windings is asymmetrical, and the potential of the tortuous structure in zero sequence and harmonic suppression is not fully utilized, which easily leads to the accumulation of phase error and load voltage distortion during the adjustment process; (3) The magnetic circuit and circuit parameters are often designed independently. The magnetic flux distribution characteristics of the tortuous primary side and the coupling matrix of the secondary side of multiple windings lack unified constraints, making it difficult to optimize the leakage inductance distribution, short-circuit impedance and magnetomotive force balance between windings as a whole; (4) Traditional phase adjustment structures mostly adopt fixed taps or mechanical switching methods, which are difficult to adapt to the requirements of modern distribution networks for fast, fine-grained adjustment and multi-condition adaptive operation.

[0008] In summary, to address the aforementioned technical shortcomings, a collaborative design method for the magnetic circuit and electrical circuit of multi-winding phase-shifting transformers is urgently needed. Summary of the Invention

[0009] Therefore, the purpose of this invention is to provide a method for the coordinated design of magnetic circuits for a tortuous primary-side multi-winding phase-shifting transformer, in order to solve the above-mentioned technical problems.

[0010] The technical solution provided by this invention is: a method for coordinated design of magnetic circuits for a tortuous primary-side multi-winding phase-shifting transformer, comprising:

[0011] Based on the target phase angle and structural constraints, the basic circuit structure is designed as a multi-winding hybrid connection structure with a zigzag Z11 connection on the primary side and a D1 connection on the secondary side.

[0012] Construct a physical topology that matches the circuit foundation; the two half-windings of the zigzag primary winding are respectively arranged in the high flux region of adjacent iron core columns, and the secondary main winding and segmented voltage regulating winding are distributed in a multi-column interlocking manner; symmetrically arranged coupling windings are introduced between the main and secondary windings;

[0013] Based on the physical topology, electrical and structural parameters are optimized to construct the circuit diagram of the phase-shifting transformer.

[0014] Specifically, the multi-winding hybrid connection structure with the primary side zigzag Z11 connection and the secondary side D1 connection is as follows: each phase winding on the primary side is divided into two half-windings with equal number of turns, which are wound on adjacent iron core columns and connected in series with opposite winding directions to form a zigzag connection; several coupling auxiliary windings are introduced on the secondary side to form a cross-connected multi-winding voltage regulating network.

[0015] Specifically, the process of constructing a phase-shifting transformer circuit diagram based on physical topology, optimizing electrical and structural parameters, includes:

[0016] Calculate the structural parameters of the phase-shifting transformer based on the target phase shift range, rated capacity, and operating frequency;

[0017] Based on the structural parameters of the phase-shifting transformer, a multi-winding coupled inductance matrix consisting of a zigzag primary winding and multiple windings is established. The self-inductance and mutual inductance parameters of each winding are solved, and the short-circuit impedance, leakage inductance distribution and phase-shifting characteristics are derived accordingly.

[0018] Based on the self-inductance and mutual inductance parameters of each winding of the phase-shifting transformer, as well as the short-circuit impedance, leakage inductance distribution, and phase-shifting characteristics, the circuit diagram of the phase-shifting transformer is constructed.

[0019] Specifically, the calculation of the phase-shifting transformer structural parameters based on the target phase shift range, rated capacity, and operating frequency includes:

[0020] The core parameters of the transformer are calculated based on the selected transformer model and original parameter data. The core diameter is calculated according to the following formula:

[0021] (1)

[0022] In the formula, D is the core diameter, K is an empirical coefficient, and S is the capacity per column of the transformer.

[0023] Based on the fact that the magnitude of magnetic flux density is inversely proportional to the number of turns in the winding, and the square of the number of turns in the winding is directly proportional to the impedance voltage, it can be concluded that the magnetic flux density is related to the impedance voltage.

[0024] The magnetic flux density is determined based on the actual requirements of the multi-winding phase-shifting transformer, and the turn potential is calculated.

[0025] (2)

[0026] In the formula, e is the turn potential. , where is the magnetic flux density This is the cross-sectional area of ​​the iron core;

[0027] The number of turns is calculated from the turn potential and voltage, where the number of turns in the high-voltage winding is:

[0028] (3)

[0029] In the formula, Rated voltage;

[0030] The number of tap turns for the voltage regulator is:

[0031] (4)

[0032] (5)

[0033] In the formula, , This refers to the number of tap turns of the voltage regulating winding;

[0034] Low-voltage winding turns: Calculate the number of turns in the phase-shifting winding and the main winding respectively based on the transformer's phase-shifting requirements and winding structure. Both follow the following relationship:

[0035] (6)

[0036] in, U is the number of turns, U is the voltage, and e is the voltage per turn.

[0037] Adjust the wire gauge and winding arrangement multiple times based on the number of turns in the winding;

[0038] No-load current From active component and reactive power The following formula can be used to calculate:

[0039] (7)

[0040] short-circuit impedance Similarly, from the resistor voltage With reactance voltage The composition is calculated according to the following formula:

[0041] (8).

[0042] Specifically, based on the structural parameters of the phase-shifting transformer, a six-winding coupled inductance matrix is ​​established, comprising a zigzag primary winding and multiple windings:

[0043] (9)

[0044] In equation (9), the unit of inductance is H. Each row of the matrix represents the inductance of the nth winding. When it is on the diagonal, the value is its own inductance value, and otherwise it is the mutual inductance value between the windings.

[0045] This invention provides a method for the coordinated design of magnetic circuits in a tortuous primary-side multi-winding phase-shifting transformer. This design method comprehensively considers electromagnetic factors such as the magnetic flux distribution of the tortuous core, winding coupling coefficients, parasitic leakage inductance, and short-circuit impedance matching, forming a complete design system from topology construction and circuit model parameter calculation to physical implementation. Compared with existing technologies, this invention, while maintaining the advantages of the tortuous primary-side structure, achieves high-resolution continuous phase shifting and parameterized design of the multi-winding secondary side, providing important technical support for constructing flexible loop-closing devices for distribution networks and a new generation of electromagnetically adjustable flexible interconnection switches. Attached Figure Description

[0046] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 A schematic diagram of the phase-shifting transformer circuit structure constructed using the design method provided in this invention;

[0049] Figure 2 The simulation waveform diagram of the phase-shifting transformer circuit provided by the present invention includes (a) the voltage waveform of the high-voltage winding circuit on the primary side of phase A; (b) the voltage waveform of the low-voltage winding circuit on the secondary side of phase A; and (c) the voltage waveform of the voltage regulating winding circuit on the secondary side of phase A.

[0050] Figure 3 The simulation waveform diagram of the phase-shifting transformer circuit provided by this invention;

[0051] Figure 4 The schematic diagram of the phase shifting principle of the phase-shifting transformer provided by the present invention. Detailed Implementation

[0052] The present invention will be further explained below with reference to specific implementation schemes, but this explanation does not limit the scope of the invention.

[0053] This invention addresses the problems of limited phase adjustment range, scattered adjustment step distance, insufficient zero-sequence and unbalance suppression capabilities, and disconnect between magnetic circuit and circuit design in existing multi-winding phase-shifting transformers. It proposes a coordinated magnetic circuit and circuit design method for a tortuous primary-side multi-winding phase-shifting transformer. This method achieves multi-level continuously adjustable phase shifting based on a natural 60° reference phase difference while maintaining the requirements of flexible loop-connected distribution networks; it provides better suppression capabilities for zero-sequence current and unbalanced loads; and it integrates and optimizes the master-slave windings, electromagnetic parameters, and topology.

[0054] The steps include the following:

[0055] S1: Based on the target phase angle and structural constraints, design the basic circuit structure; the primary winding adopts a zigzag Z11 connection group, and each phase primary winding consists of two half-windings wound on two adjacent iron core columns. The half-windings have the same number of turns and opposite winding directions, and are connected in series through a bend-waist connection method, forming a Z11 group with the three phases connected; the secondary main winding adopts a D1 connection method. Through this specific connection group combination, an initial voltage phase difference of approximately 60° is formed between the primary and secondary sides.

[0056] This step first clarifies the transformer's operational objectives and functional requirements, namely, to achieve controllable and continuous phase adjustment based on the natural phase difference, while also considering zero-sequence suppression and unbalanced operation performance. Based on the phase offset requirements of different feeder lines and grid connection interfaces in the power system, the basic phase shift angle is determined during the design phase through a reasonable combination of primary and secondary winding connection methods.

[0057] A multi-winding hybrid connection structure with a zigzag Z11 connection on the primary side and a D1 connection on the secondary side is adopted. Each phase winding on the primary side is divided into two equal-turn half-windings, wound on adjacent core columns and connected in series with opposite winding directions to form a bend-waist connection. This achieves phase characteristics equivalent to Y11 under fundamental conditions while improving zero-sequence flux distribution. The secondary side uses a D1 connection as the main output winding, and several coupled auxiliary windings are introduced on the secondary side to form a cross-connected multi-winding voltage regulation network. By rationally configuring the phasor superposition relationship of the primary and secondary side connection groups and auxiliary windings, continuous and controllable phase shift is achieved based on a natural 60° phase difference. This step is based on the composite connection group of the zigzag Z11 primary winding and the D1 secondary winding, and by introducing a multi-winding hybrid connection structure and a quantity-assisted adjustment mechanism on the secondary side, a circuit topology capable of continuous phase shift is constructed. Without altering the main magnetic circuit reference structure, the multi-level continuously adjustable phase shift capability is achieved by utilizing the superposition of potentials and magnetomotive force compensation between multiple auxiliary coupling windings, based on a natural 60° phase difference. Simultaneously, by leveraging the absorption capability of the tortuous primary side against zero-sequence and unbalanced components, the operational stability of the multi-winding phase-shifting transformer under asymmetrical operating conditions is improved.

[0058] The above steps introduce a zigzag Z11 primary side structure into a multi-winding phase-shifting transformer for the first time. While maintaining a natural 60° reference phase difference, the zigzag connection improves the distribution of zero-sequence flux and magnetomotive force under unbalanced loads, achieving an integrated design of phase-shifting function and zero-sequence / unbalance suppression function, which is superior to the traditional fixed phase-shifting structure with a single D11 connection. By combining "main winding + low-voltage main winding + multi-segment voltage-regulating winding" to form a topology of six windings coupled per phase, a voltage vector superposition network combining cross-phase series and segmented voltage regulation is introduced. Based on the natural 60° phase difference, a wide-range, multi-level, and high-resolution continuously adjustable phase shift is achieved. Compared with the traditional discrete adjustment scheme relying on a single winding tap, the phase shifting accuracy is higher and the adjustment step is finer.

[0059] S2: Construct a physical topology that matches the circuit foundation: Based on the circuit design results, construct a physical topology that matches it.

[0060] The two half-windings of the zigzag primary winding are arranged in the high flux regions of adjacent core columns to ensure the continuity of the main flux path. The secondary main winding and multiple voltage regulating windings are distributed in a multi-column interlocking manner to achieve coupling of six windings per phase. By introducing symmetrically arranged coupling windings between the main and secondary windings, the voltage injection path is clear, the flux linkage distribution is balanced, and the interphase coupling is controllable, thereby improving the accuracy and repeatability of phase adjustment.

[0061] During the topology construction phase, the design focus shifts from electrical principles to physical implementation. The topology of the phase-shifting transformer directly determines the magnetic coupling path, leakage flux distribution, and the accuracy of voltage phase shift. The core type, winding arrangement, coil arrangement, and nesting relationship of auxiliary windings all need to be comprehensively considered.

[0062] In this embodiment, the two half-windings of the primary side zigzag winding are respectively arranged in the high flux region of two adjacent core columns to maintain good main flux continuity and low leakage inductance. The secondary side main winding, voltage regulating winding, and energy harvesting winding are symmetrically distributed on each core column, forming a six-winding coupling space configuration per phase. The primary and secondary windings are preferentially arranged in the high flux region of the core to maintain good coupling and low leakage inductance, while the auxiliary windings are arranged symmetrically or in a coupled superposition manner to ensure three-phase flux balance. During the structural design process, the core utilization rate, heat dissipation conditions, insulation coordination, and manufacturing complexity must be balanced. To reduce the phase error caused by parasitic coupling, a shielding layer and an independent auxiliary window are introduced between the primary and secondary windings to achieve electrical isolation and electromagnetic compatibility.

[0063] like Figure 3 As shown, in this embodiment, the incoming line is directly connected to the primary side zigzag high-voltage winding, forming a 20kV high-voltage side; the secondary side includes a low-voltage main winding, segmented voltage regulating windings, and energy extraction windings. One end of the low-voltage main winding is directly connected to the line, and the other end is connected to the voltage regulating winding. As the core part of the phase-shifting function, the voltage regulating winding is divided into two segments per phase, each segment having multiple taps, and is divided into 200V and 400V parts, thus enabling 7 voltage levels (200V, 400V, 600V, -200V, -400V, -600V, 0V) on each segment. The three voltage regulating windings are connected in series across phases: one end of the first voltage regulating winding of phase A is connected to the low-voltage winding of this phase, and the other end is connected to the second voltage regulating winding of phase B, and so on, completing a closed loop of six voltage regulating windings for phases A, B, and C. This design, while simplifying the transformer structure as much as possible, achieves multi-level voltage amplitude and phase joint regulation. The vector relationship of its phase regulation function is as follows: Figure 4 As shown.

[0064] S3: Optimize electrical and structural parameters based on physical topology: Based on the above topology, carry out parametric design and optimization.

[0065] S31: Calculate the appropriate core cross-section, number of winding turns, conductor cross-sectional area, and insulation layer thickness based on the target phase shift range, rated capacity, and operating frequency;

[0066] Multi-winding transformers can be fully utilized in the phase-shifting process of loop closing. To design a multi-winding phase-shifting transformer, the core parameters must first be calculated based on the selected transformer model and original parameter data. The core diameter is generally calculated using the following formula:

[0067] (1)

[0068] In the formula, D is the core diameter, K is an empirical coefficient, and S is the capacity per column of the transformer.

[0069] The magnitude of magnetic flux density is inversely proportional to the number of turns in the winding, while the square of the number of turns is directly proportional to the impedance voltage; that is, magnetic flux density is related to impedance voltage. After determining the magnetic flux density based on the actual requirements of a multi-winding phase-shifting transformer, the turn potential can be calculated.

[0070] (2)

[0071] In the formula, e is the turn potential. , where is the magnetic flux density Let be the cross-sectional area of ​​the iron core.

[0072] The number of turns can be calculated from the turn potential and voltage. The number of turns in the high-voltage winding is as follows:

[0073] (3)

[0074] In the formula, For the rated voltage, the corresponding number of turns of the voltage regulating tap is:

[0075] (4)

[0076] (5)

[0077] In the formula, , This refers to the number of tap turns of the voltage regulating winding.

[0078] When calculating the number of turns in the low-voltage winding, the number of turns in the phase-shifting winding and the number of turns in the main winding need to be calculated separately according to the phase-shifting requirements and winding structure of the transformer. Both follow the following relationship:

[0079] (6)

[0080] in, U is the number of turns, U is the voltage, and e is the calculated turn potential.

[0081] Once the number of turns in the winding is determined, the winding size is directly related to the specifications of the electromagnetic wire and the winding arrangement, as well as the impedance voltage and losses. Therefore, the selection of the electromagnetic wire and the winding arrangement must meet the requirements of impedance voltage, and generally require multiple adjustments to the wire gauge and winding arrangement.

[0082] No-load current From active component and reactive power The following formula can be used to calculate:

[0083] (7)

[0084] short-circuit impedance Similarly, from the resistor voltage With reactance voltage The composition is calculated according to the following formula:

[0085] (8)

[0086] The preliminary structural data of the phase-shifting transformer obtained according to the calculation process are shown in Table 1.

[0087] Table 1. Structural parameters of the phase-shifting transformer

[0088] Iron core diameter / mm High voltage winding cross-sectional area / mm2 Low voltage winding cross-sectional area / mm2 Window height / mm 246 44.84 23.74 756

[0089] Calculations and verifications have shown that the basic performance of the transformer meets the relevant requirements.

[0090] Any aspects not covered in this invention are applicable to existing technologies.

[0091] S32: By establishing a six-winding coupled inductance matrix consisting of a zigzag primary winding and multiple windings, the self-inductance and mutual inductance parameters of each winding are solved, and the short-circuit impedance, leakage inductance distribution and phase shift characteristics are derived accordingly.

[0092] This invention relates to a phase-shifting transformer with a total of 6 coupled windings, which have self-inductance and mutual inductance. The inductance values ​​calculated based on the initial transformer structural parameters are shown in the following matrix:

[0093] (9)

[0094] The inductance unit in the above formula is H. Each row of the matrix represents the inductance of the nth winding. When it is on the diagonal, the value is its own inductance value, otherwise it is the mutual inductance value between the windings. The circuit and 3D simulation are both simulated according to the above inductance values.

[0095] By establishing an inductance matrix that includes a tortuous primary winding and multiple windings, and by uniformly considering factors such as core flux distribution, winding coupling coefficient, leakage inductance, and short-circuit impedance, the magnetic circuit design and circuit topology design are upgraded from separate calculations to integrated collaborative optimization. This significantly improves the accuracy of parameter calculations and the predictability of design results, and reduces the costs of prototype debugging and repeated trial production.

[0096] Based on the circuit distribution and coupling relationship of the phase-shifting transformer, a system was established as follows: Figure 1 The circuit inductance simulation model shown:

[0097] Simulation verification was conducted at a 50Hz power frequency. The voltage waveforms of the primary winding, the secondary low-voltage winding, and the regulating winding were measured respectively. The simulation waveforms obtained under these conditions are as follows: Figure 2 As shown, simulations were performed under a 50Hz power frequency condition, and the voltage waveforms of the primary side zigzag high-voltage winding, the secondary side low-voltage main winding, and the voltage regulating winding were measured respectively, yielding the following results: Figure 2 The simulation results are shown in the figure. As can be seen from the figure, the primary and secondary sides of the phase-shifting transformer have achieved the expected phase relationship under the reference structure; when the equivalent inductance value in the circuit is changed or the winding connection method is adjusted, the theoretical phase-shifting function is realized. For example, when the peak phase shift time is set to 0.002s, the comparison of the circuit voltage waveform results shows that the peak voltage of the primary side is still 0.086s, while the peak time of the low-voltage winding and the voltage regulating winding of the secondary side shifts to 0.084s, which is consistent with the initially set peak time shift, verifying the feasibility of the tortuous primary side multi-winding phase-shifting transformer circuit topology.

[0098] This invention optimizes the winding coupling matrix, the segmented structure of the voltage regulating winding, the voltage vector superposition path, and the spatial distribution of the auxiliary winding on the core column. This method achieves precise control of the circuit vector based on the tortuous magnetic circuit constraint, significantly improving phase shift accuracy, adjustment continuity, and load stability.

[0099] The topology and design method proposed in this invention can adjust the number of secondary windings, voltage regulation segments, and tap configuration according to different engineering needs without changing the tortuous structure of the primary side. This enables flexible configuration from small-scale fine phase shifting to large-scale wide-range phase shifting, and is applicable to various application scenarios such as flexible loop closing of distribution networks, grid connection of distributed power sources, and phase angle balancing of multi-feeder lines. It has good engineering promotion value.

[0100] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0101] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for coordinated magnetic circuit design of a tortuous primary-side multi-winding phase-shifting transformer, characterized in that, include: Based on the target phase angle and structural constraints, the basic circuit structure is designed as a multi-winding hybrid connection structure with a zigzag Z11 connection on the primary side and a D1 connection on the secondary side. Construct a physical topology that matches the circuit foundation; the two half-windings of the zigzag primary winding are respectively arranged in the high flux region of adjacent iron core columns, and the secondary main winding and segmented voltage regulating winding are distributed in a multi-column interlocking manner; symmetrically arranged coupling windings are introduced between the main and secondary windings; Based on the physical topology, electrical and structural parameters are optimized to construct the phase-shifting transformer circuit diagram, including: Calculate the structural parameters of the phase-shifting transformer based on the target phase shift range, rated capacity, and operating frequency; Based on the structural parameters of the phase-shifting transformer, a multi-winding coupled inductance matrix consisting of a zigzag primary winding and multiple windings is established. The self-inductance and mutual inductance parameters of each winding are solved, and the short-circuit impedance, leakage inductance distribution and phase-shifting characteristics are derived accordingly. Based on the self-inductance and mutual inductance parameters of each winding of the phase-shifting transformer, as well as the short-circuit impedance, leakage inductance distribution, and phase-shifting characteristics, the circuit diagram of the phase-shifting transformer is constructed.

2. The magnetic circuit collaborative design method for the tortuous primary-side multi-winding phase-shifting transformer according to claim 1, characterized in that, The multi-winding hybrid connection structure with the primary side zigzag Z11 connection and the secondary side D1 connection is as follows: each phase winding on the primary side is divided into two half-windings with equal number of turns, which are wound on adjacent iron core columns and connected in series with opposite winding directions to form a zigzag connection; several coupling auxiliary windings are introduced on the secondary side to form a cross-connected multi-winding voltage regulating network.

3. The magnetic circuit collaborative design method for the tortuous primary-side multi-winding phase-shifting transformer according to claim 1, characterized in that, The calculation of the structural parameters of the phase-shifting transformer based on the target phase shift range, rated capacity, and operating frequency includes: The core parameters of the transformer are calculated based on the selected transformer model and original parameter data. The core diameter is calculated according to the following formula: (1) In the formula, D is the core diameter, K is an empirical coefficient, and S is the capacity per column of the transformer. Based on the fact that the magnitude of magnetic flux density is inversely proportional to the number of turns in the winding, and the square of the number of turns in the winding is directly proportional to the impedance voltage, it can be concluded that the magnetic flux density is related to the impedance voltage. The magnetic flux density is determined based on the actual requirements of the multi-winding phase-shifting transformer, and the turn potential is calculated. (2) In the formula, e is the turn potential. , where is the magnetic flux density This is the cross-sectional area of ​​the iron core; The number of turns is calculated from the turn potential and voltage, where the number of turns in the high-voltage winding is: (3) In the formula, Rated voltage; The number of tap turns for the voltage regulator is: (4) (5) In the formula, , This refers to the number of tap turns of the voltage regulating winding; Low-voltage winding turns: Calculate the number of turns in the phase-shifting winding and the main winding respectively based on the transformer's phase-shifting requirements and winding structure. Both follow the following relationship: (6) in, U is the number of turns, U is the voltage, and e is the voltage per turn. Adjust the wire gauge and winding arrangement multiple times based on the number of turns in the winding; No-load current From active component and reactive power The following formula can be used to calculate: (7) short-circuit impedance Similarly, from the resistor voltage With reactance voltage The composition is calculated according to the following formula: (8)。 4. The magnetic circuit collaborative design method for the tortuous primary-side multi-winding phase-shifting transformer according to claim 1, characterized in that, Based on the structural parameters of the phase-shifting transformer, a six-winding coupled inductance matrix is ​​established, comprising a zigzag primary winding and multiple windings: (9) In equation (9), the unit of inductance is H. Each row of the matrix represents the inductance of the nth winding. When it is on the diagonal, the value is its own inductance value, and otherwise it is the mutual inductance value between the windings.

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