A twelve-phase generator-based ac-dc power system and a power supply method thereof

Abstract

The application relates to a kind of AC / DC power system based on twelve-phase generator and its power supply method, the power system includes power machine, twelve-phase generator, rectifier, filter unit and phase transformer;Single set of twelve-phase star-shaped armature winding is arranged on the stator of the generator, and excitation winding is arranged on the rotor;The output end of the generator is divided into two parallel roads, one road is connected with rectifier and filter unit in turn, for outputting DC;The other road is connected with phase transformer, and the phase transformer transforms twelve-phase AC containing four three-phase electric into one road full-power AC through a group of three-phase end points;The sum of the respective power outputs of twelve-phase AC and DC of the twelve-phase generator is the apparent output power of the generator, and the respective power outputs of AC and DC are not proportionally limited;The system can output AC and DC simultaneously without electronic inverter, which improves the versatility, reliability, economy and redundancy of the system.

Description

Technical Field

[0001] This application relates primarily to the field of power technology, and in particular to an AC / DC power system based on a twelve-phase generator and its power supply method. Background Technology

[0002] Various types of electricity are required in various industries and daily life sectors. The public power grid used for power supply, that is, the power grid that provides single-phase or three-phase alternating current with standard voltage and standard frequency, can be considered as the largest energy system shared by society. It also serves as the power supply system for local power grids such as ship inspection and aircraft. The AC / DC power system described in this invention broadly refers to various power systems at the level of ships, mobile bodies, islands, computing centers, local power grids, and even national or regional power grids.

[0003] The superior performance of alternating current (AC) makes it the preferred choice for electric drives. However, besides AC power, current electronic, communication, and digital devices on ships are better suited to direct current (DC) power. DC is more stable, reliable, and cleaner than AC, and is also more suitable for energy storage. From the perspective of energy conservation and carbon emission reduction trends, the use of new energy sources on ships is receiving increasing attention from various countries. Photovoltaic power generation is DC, and the application of DC is becoming increasingly widespread. DC is continuously expanding into areas previously dominated by AC power, such as LED lights in lighting systems and variable-speed motors in variable-frequency air conditioners. The proportion of DC power in advanced ship inspection systems has also been rapidly increasing recently. Currently, advanced ship inspection systems and aircraft abroad all employ AC / DC multi-system power supply technology. my country's ship inspection and aircraft have also begun to establish medium-voltage DC integrated power systems, with the original AC power supply system evolving towards a DC power supply system. Many Chinese ships have adopted a DC power supply system using multi-phase AC rectifier generators.

[0004] In 2017, my country issued the national standard "General Requirements for Medium-Voltage DC Power Systems for Ships" (GB / T 35719-2017), providing specifications for the design and manufacture of new power systems. In 2024, the monograph "Integrated Medium-Voltage DC Power Systems for Ships," compiled by experts including Zhang Yigang from the 704 Research Institute, systematically integrated cutting-edge research findings in this field, from generator grid connection and hybrid energy storage control to fault protection, becoming an important technical guide. Currently, there are two main types of advanced shipboard AC / DC power systems based on multiphase generators.

[0005] The first type is a variable-speed AC rectifier power generation system based on a permanent magnet multiphase generator. The power source of this system is a high-speed turbine, and the generator is a variable-speed AC rectifier generator with four sets of three-phase windings. The four independent three-phase power supplies are rectified and DC regulated separately before being connected in series to obtain 3000V high-voltage DC. The AC power is constant-frequency, constant-voltage industrial-frequency AC power obtained from the DC output through a DC / AC power electronic inverter. The advantages of this technical solution are the high efficiency of the permanent magnet motor and the small size and weight of the high-speed motor. The disadvantages are the high cost of the power electronic inverter and its vulnerability to voltage and current surges. Furthermore, the generator outputs AC power, but it requires a secondary power conversion from DC to AC, resulting in poor technical rationality and multiple energy conversions that affect the overall power efficiency.

[0006] The second type of AC / DC power system uses a dual-winding AC rectifier generator. This generator is a constant-frequency, constant-voltage excitation type, with one winding being a multi-phase winding (greater than three phases) that generates AC power which is then rectified to obtain stable DC power. The other winding is a three-phase winding that directly outputs standard industrial-frequency three-phase power. Its advantages include eliminating the need for a DC / AC power electronic inverter, resulting in high system economy and reliability; additionally, there is no electrical connection between the AC and DC systems, leading to high safety. However, its disadvantages include insulation between the two windings, and the additional second layer of insulation occupying a portion of the limited slot area of ​​the motor's magnetic circuit, thus reducing the motor's output power. More importantly, the ratio of AC to DC output power is locked by the pre-designed motor structure, lacking direct substitution and flexible application of AC and DC power, resulting in insufficient versatility of the power system. Summary of the Invention

[0007] The purpose of this application is to provide an AC / DC power system based on a twelve-phase generator and its power supply method, in order to solve the problems of low power supply efficiency, reduced output power, inflexible AC / DC power ratio, and insufficient system versatility in the prior art.

[0008] According to one aspect of this application, an AC / DC power system based on a twelve-phase generator is provided, including a power unit and a twelve-phase generator, wherein the twelve-phase generator is a brushed synchronous motor or a brushless synchronous motor, and the power unit is used to drive the twelve-phase generator to output twelve-phase AC power; the system further includes a rectifier, a filter unit, and a phase transformer; The stator of the twelve-phase generator is uniformly arranged with a single set of twelve-phase armature windings along the circumference, and the rotor is provided with an excitation winding for passing excitation current to establish a rotor magnetic field. The output terminals of the twelve-phase armature winding are divided into two parallel paths. One path is connected to the rectifier and the filter unit in sequence to output DC power. Another path is connected to the phase transformer, which converts the twelve-phase AC power containing four sets of three-phase electricity into a single full-power AC output through a set of three-phase terminals.

[0009] Optionally, the twelve-phase armature winding adopts a star connection, and the neutral point of the star connection is grounded through a resistor to limit the short-circuit current generated by the twelve-phase armature winding or DC output terminal due to a ground fault.

[0010] Optionally, the transformer has six iron cores and a primary winding wound on each iron core. The six iron cores are divided into a first iron core group and a second iron core group. The primary winding in each iron core group includes two sets of three-phase terminals. Each set of three-phase terminals is used to connect to one set of three-phase power in the twelve-phase AC power. The center terminals of each set of three-phase voltages are connected by a neutral point, and any set of three-phase terminals is used as an output terminal to output a full-power AC power. Each core of the first core group is also wound with two electrically isolated secondary windings, which are electromagnetically coupled to the primary windings on the same core. The primary winding on the first core group is connected to either an odd-numbered phase voltage or an even-numbered phase voltage, while the primary winding on the second core group is connected to the other. The center ends of all the primary windings are connected together. The odd-numbered phase voltage and the even-numbered phase voltage are obtained by dividing the twelve-phase alternating current.

[0011] Optionally, each core of the second core group is further wound with a secondary winding, the secondary winding of the second core group including a set of three-phase terminals, which are used as the output terminals to output the full-power alternating current.

[0012] Optionally, the primary winding wound on each iron core is connected to two phase voltages with opposite phases in the same phase voltage, and the center end divides the primary winding into two half windings, each of the half windings corresponding to one of the two phase voltages with opposite phases. The two secondary windings on each core in the first core group correspond to the two phase voltages with opposite phases connected to the primary winding on the same core. In the first core group, the secondary windings of two phase voltages located on two different cores and corresponding to a phase difference of 60° are connected in series. The three equivalent phase voltages in another set of phase voltages are generated by phasor synthesis. Each of the equivalent phase voltages is connected to the same-name terminal of the primary winding of the corresponding core in the second core group to establish an electrical connection between the phase voltages of the first core group and the second core group.

[0013] Optionally, the number of turns in each secondary winding of the first core assembly is n times the number of turns in the corresponding primary half-winding. times.

[0014] Optionally, the phase transformer includes a first transformer and a second transformer; The first transformer includes three cores of the first core group, and the second transformer includes three cores of the second core group.

[0015] Optionally, both the first transformer and the second transformer are three-phase planar transformers, wherein the three cores of the three-phase planar transformer are arranged side by side in the same plane and connected by a common magnetic yoke.

[0016] Optionally, both the first transformer and the second transformer are three-phase three-dimensional transformers. The three iron cores of the three-phase three-dimensional transformer are arranged in an equilateral triangle and inserted into the slots of the upper and lower magnetic yokes, respectively.

[0017] Optionally, the phase transformer is a single six-phase three-dimensional transformer, wherein the six iron cores are arranged at equal distances in a clockwise or counterclockwise direction along the circumference and are respectively inserted into the slots of the upper and lower magnetic yokes; The arrangement of the six iron cores along the circumference is consistent with the phase sequence of the phase voltages they are connected to, such that the primary windings connected to odd-numbered phase voltages and the primary windings connected to even-numbered phase voltages are arranged alternately along the circumference in the order C1-C6.

[0018] Optionally, the system further includes a first fuse group and a second fuse group; Each fuse in the first fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding positive terminal rectifier branch of the rectifier. Each fuse in the second fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding negative rectifier branch of the rectifier; Each input terminal of the phase transformer is connected to the connection point between the first or second fuse group and the positive or negative rectifier branch of the rectifier.

[0019] Optionally, the system further includes a speed governor and an automatic voltage regulator; The speed regulator is used to automatically adjust the power supply of the power unit according to the speed change of the power unit, so as to make the power unit run at a constant speed; The automatic voltage regulator is used to adjust the excitation current in the excitation winding according to the deviation between the output voltage of the twelve-phase generator and a preset value, so as to make the twelve-phase generator output a constant voltage.

[0020] According to another aspect of this application, an AC / DC power supply method based on a twelve-phase generator is also provided, applied to a system as described in any of the preceding claims, the method comprising: The power unit drives the twelve-phase generator at a constant speed and supplies excitation current to the excitation winding on the rotor, so that the twelve-phase armature winding outputs a constant frequency and constant voltage twelve-phase alternating current. The output terminals of the twelve-phase armature winding are divided into two parallel paths. The twelve-phase AC power output from one path is rectified by the rectifier and filtered by the filter unit to output DC power. The twelve-phase AC power output from another path is input into the phase transformer. The phase voltages of the twelve-phase AC power are divided into two phase voltage groups according to the phase sequence. By combining the phasors of two adjacent phase voltages in the same group within the phase transformer, an equivalent phase voltage in the other group is generated. The generated equivalent phase voltage is electrically connected to the corresponding phase voltage in the other group to establish an electrical connection between the windings corresponding to the two groups of phase voltages. Combined with the magnetic field coupling within the phase transformer, all windings of the twelve-phase armature winding are electromagnetically linked and electromagnetically coupled. Therefore, even if only one set of three-phase windings is connected to the output terminal, all generator windings can still share the AC power output. The output terminal of the transformer outputs three-phase AC power shared by the entire winding. The output terminal can be any set of three-phase terminals of the primary winding to achieve input and output terminal sharing, or a set of three-phase terminals of the secondary winding of the second core group to achieve electrical isolation.

[0021] Optionally, the two phase voltage groups of the twelve-phase alternating current are respectively an odd-numbered phase voltage group composed of odd-numbered phase voltages and an even-numbered phase voltage group composed of even-numbered phase voltages, and the phase difference between the two adjacent phase voltages is 60°. The phasor synthesis is performed by the transformer, where each phase corresponds to one of the two adjacent phase voltages and has a number of turns corresponding to the number of turns n of the primary half-winding. The two secondary windings are connected in series to achieve the same value, and the phase difference between the generated equivalent phase voltage and the two adjacent phase voltages is 30°.

[0022] Compared with existing technologies, this application, through an AC / DC power system and power supply method based on a twelve-phase generator, leverages a single-set multi-phase armature winding structure design and an electromagnetically coupled phase-changing transformer to achieve dual AC / DC output. This improves generator power density and operating efficiency while enabling flexible allocation of AC / DC output power, combining high reliability with high economy. Consequently, it achieves greater generator output power and higher generator efficiency; wider versatility, eliminating limitations on the proportion of AC / DC power usage; greater system reliability and redundancy; and greater system technical and economic benefits. Attached Figure Description

[0023] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This diagram illustrates a prior art twelve-phase generator DC power system circuit. Figure 2 This shows a block diagram of a traditional AC / DC power system; Figure 3 A schematic diagram of an AC / DC power system provided according to one aspect of this application is shown; Figure 4 This invention illustrates the phasor diagram of the output voltage of a twelve-phase generator with a star connection used in one embodiment of the present application. Figure 5 This invention illustrates a phasor comparison diagram of three-phase and twelve-phase induced voltages in one embodiment of the present application. Figure 6 This invention illustrates a circuit diagram of a twelve-phase generator output circuit breaker and rectifier in one embodiment of the present application. Figure 7 This diagram illustrates electromagnetic coupling phasor synthesis in one embodiment of the present application. Figure 8(a) shows a wiring diagram of an electromagnetic coupling phase transformer in one embodiment of this application; Figure 8(b) shows a wiring diagram of an electromagnetic coupling phase transformer with an electrically isolated winding in one embodiment of this application; Figure 9 This diagram shows a split magnetic circuit structure of a laminated three-phase transformer according to an embodiment of this application. Figure 10 This diagram shows a split magnetic circuit structure of a hybrid three-phase transformer according to an embodiment of this application. Figure 11 This document shows an external view of a six-phase three-dimensional transformer according to one embodiment of the present application. Figure 12 This invention provides a structural block diagram of a simplified AC / DC power system according to one embodiment of the present application. Figure 13 This diagram illustrates a block diagram of a PMS-controlled AC / DC power system according to an embodiment of this application.

[0024] Figure label: 110 power unit 120 Three-phase generator 130 rectifier transformer 140 rectifier 150 filter units 160 circuit breaker 161 DC circuit breaker 162 AC circuit breaker 170 Power Plant Automation Equipment 220 twelve-phase generator 240 controller 250 Automatic Voltage Regulator 300 phase transformer 301 iron core 310 Upper Magnetic Yoke 320 Lower yoke 321 Circular groove The same or similar reference numerals in the accompanying drawings represent the same or similar parts. Detailed Implementation

[0025] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0026] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein, and therefore this application is not limited to the specific embodiments disclosed below.

[0027] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0028] Currently, advanced shipboard AC / DC power systems with multiphase generators as the core technology are mainly divided into two categories. Figure 1 The first type is a variable-speed AC rectifier generator composed of a permanent magnet multiphase generator. The power unit T is a high-speed turbine, and the generator is a variable-speed AC rectifier generator with four sets of three-phase windings. The four independent three-phase power supplies are rectified and DC regulated separately before being connected in series to obtain 3000V high-voltage DC. The AC power is constant-frequency and constant-voltage industrial frequency AC power obtained from the DC output terminal through a DC / AC power electronic inverter. The advantages of this technical solution are the high efficiency of the permanent magnet motor and the small size and weight of the high-speed motor. The disadvantages are the high cost of the power electronic inverter and its vulnerability to voltage and current surges. Furthermore, the fact that it requires a secondary power conversion from DC to AC despite being an AC generator results in poor technical rationality and multiple energy conversions that affect the overall power efficiency.

[0029] The second type of AC / DC power system uses a dual-winding AC rectifier generator. This generator is a constant-frequency, constant-voltage excitation type, with one winding being a multi-phase winding (greater than three phases) that generates AC power which is then rectified to obtain stable DC power. The other winding is a three-phase winding that directly outputs standard industrial-frequency three-phase power. Its advantages include eliminating the need for a DC / AC power electronic inverter, resulting in high system economy and reliability; additionally, there is no electrical connection between the AC and DC systems, leading to high safety. However, its disadvantages include insulation between the two windings, and the additional second layer of insulation occupying a portion of the limited slot area of ​​the motor's magnetic circuit, thus reducing the motor's output power. More importantly, the ratio of AC to DC output power is locked by the pre-designed motor structure, lacking direct substitution and flexible application of AC and DC power, resulting in insufficient versatility of the power system.

[0030] To address the shortcomings of the two existing types of typical advanced AC / DC power systems and to meet the needs of economy and versatility, the technical solution in this application is based on the most economical and fundamental solution, namely, the traditional solution that is closest to a three-phase generator plus a three-phase rectifier. However, this solution suffers from poor DC voltage stability, large ripple and harmonics, and low power quality after three-phase rectification. Therefore, high-power AC / DC power systems typically require the addition of a rectifier transformer before the rectifier to increase the number of phases of the three-phase input power to quasi-six-phase or twelve-phase.

[0031] Figure 2 This diagram illustrates a conventional AC / DC power system with a rectifier transformer. In the diagram, a power unit 110 drives a three-phase generator 120 to generate three-phase AC power at a constant speed. One path of the three-phase AC power is directly transmitted to the AC bus, while the other path is rectified by a three-phase rectifier transformer 130 and a rectifier 140 before being transmitted to the DC bus, thus forming a conventional AC / DC power system.

[0032] exist Figure 2 In this system, the power unit 110 drives the three-phase generator 120 to generate constant-frequency, constant-voltage three-phase AC power, which is directly supplied to the AC load. Simultaneously, the three-phase AC power is connected to a rectifier transformer 130 to convert it into quasi-six-phase or twelve-phase power. Then, a rectifier 140 rectifies the multi-phase power (greater than three phases) to output stable, high-quality DC power. The energy efficiency of this basic AC / DC power system is generally low, and its redundancy is very poor. If one phase of the generator fails, the three-phase power output becomes single-phase power; if two phases fail, the power output capacity is even lower or may even drop to zero.

[0033] This application presents a new technological solution based on a three-phase generator with a rectifier transformer. Since an additional transformer is needed to convert three-phase electricity to twelve-phase electricity, it's more efficient to first convert the three-phase generator into a multi-phase generator at a low cost, directly generating more than three-phase AC power, thus eliminating the need for a separate transformer. Figure 2The rectifier transformer 130 is used in this system. However, this change results in the problem that multiphase electricity cannot be supplied to the current three-phase power system under AC power. Therefore, a phase-changing transformer needs to be configured again to convert multiphase electricity to three-phase AC power.

[0034] It should be noted that the phase-changing transformer referred to in this application can also be called a phase-shifting transformer or a phase-changing transformer, which is a transformer device used to change the phase or number of phases of alternating current.

[0035] It should be particularly pointed out that, Figure 2 Although the rectifier transformer in the proposed solution and the phase-changing transformer in this application both fall under the functional category of phase-changing transformers, their functional characteristics are completely different and they generally cannot be reverse-substituted for each other. A typical rectifier transformer can only convert a few-phase AC power to a multi-phase AC power, and cannot be used in reverse to convert multi-phase AC power to a few-phase AC power; similarly, a typical phase-changing transformer cannot be used in reverse. Therefore, Figure 2 Structure and Figure 3 Although the structures are similar at the block diagram level, the direction of conversion from three-phase to multi-phase and from multi-phase to three-phase is reversed. It is not a simple equivalent replacement, and a new structure of electromagnetically coupled phase-changing transformer, as described below, is required to achieve an engineering-usable solution. In addition, from a cost perspective, the increased cost of replacing a three-phase generator with a twelve-phase generator is not significant, and the replacement of the rectifier transformer with a phase-changing transformer is a component of equivalent value. Therefore, the new structure maintains essentially the same system cost.

[0036] The AC / DC power system and power supply method based on a twelve-phase generator provided in this application are grounded in a single-set multi-phase armature winding structure design. Combined with an electromagnetically coupled phase-changing transformer, it achieves dual AC / DC output, improving generator power density and operating efficiency while enabling flexible allocation of AC / DC output power, thus combining high reliability and high economy. This results in greater generator output power and higher generator efficiency; wider versatility, eliminating limitations on the proportion of AC / DC power usage; greater system reliability and redundancy; and greater system technical and economic benefits.

[0037] Figure 3This application illustrates an AC / DC power system based on a twelve-phase generator according to one aspect of the present application, comprising a power unit 110 and a twelve-phase generator 220, wherein the twelve-phase generator 220 is a brushed synchronous motor or a brushless synchronous motor, and the power unit 110 is used to drive the twelve-phase generator 220 to output twelve-phase AC power; the system further includes a rectifier 140, a filter unit 150, and a phase transformer 300; a single set of twelve-phase armature windings are evenly arranged along the circumference on the stator of the twelve-phase generator 220, and an excitation winding is provided on the rotor for passing excitation current to establish a rotor magnetic field; the output terminals of the twelve-phase armature windings are divided into two parallel paths, one path is connected sequentially to the rectifier 140 and the filter unit 150 for outputting DC power; the other path is connected to the phase transformer 300, which converts the twelve-phase AC power containing four sets of three-phase electricity into a single full-power three-phase AC power output through a set of three-phase terminals.

[0038] During operation, the power unit 110 drives the twelve-phase generator 220 to generate constant-frequency, constant-voltage twelve-phase AC power. One path of the twelve-phase AC power is directly input to the rectifier, and after rectification and filtering, it outputs high-quality DC power. The other path of the twelve-phase AC power is input to the phase transformer 300, and through electromagnetic coupling and phasor transformation, it is converted into standard three-phase AC power for external power supply. Compared with traditional dual-winding AC / DC generators, this solution uses a single set of twelve-phase armature windings to achieve dual AC / DC output. It eliminates the need for two independent windings and interlayer insulation in the motor slot, saving effective space in the motor slot, increasing the conductor cross-sectional area, and improving the motor's power density and output capacity. At the same time, the AC / DC output power is determined only by the load demand and is not limited by the preset ratio of the motor winding structure. It can flexibly adapt to application scenarios with different AC / DC load ratios, significantly improving the system's versatility.

[0039] The sum of the AC and DC power outputs of the twelve-phase generator 220 constitutes the apparent output power of the generator, and there is no proportional limitation on the AC and DC power outputs. Specifically, since both the AC and DC branches are drawn from the same set of twelve-phase armature windings, and they are connected in parallel at the output terminals of the armature windings, the sum of the apparent power absorbed by the AC load and the power absorbed by the DC load is equal to the apparent output power of the twelve-phase generator under rated operating conditions. Provided that this rated apparent power is not exceeded, the respective proportions of the AC and DC sides are entirely determined by the actual load, and they can be arbitrarily allocated between zero and full load. It can output either all AC or all DC power, without any pre-locked proportional relationship based on the winding structure. This is the fundamental difference between this application and a dual-winding AC / DC generator in terms of versatility: the capacity of the two sets of windings in the latter is fixed during motor design and manufacturing, and the AC / DC power ratio cannot be adjusted during operation, while the AC and DC power of this application have direct mutual substitution.

[0040] The generator principle of an AC synchronous generator is as follows: the rotor magnetic field rotates with the rotor, causing a periodic change in the magnetic flux coupled to the stator armature winding, thus inducing a voltage in the winding. After the winding is connected to an external circuit, an induced current flows through it. The product of the induced voltage and the current is the generator's output power. Therefore, under the condition that the rotor magnetic field and winding current are constant, the utilization factor of the induced voltage in the winding directly determines the generator's output capacity. This is also the physical starting point for this application to replace the three-phase winding with a twelve-phase winding.

[0041] The main body of the 12-phase generator 220 consists of a stator and a rotor. Twelve sets of concentrated or distributed windings are evenly arranged on the entire circumference of the stator. To reduce generator copper losses, the armature winding can be made of electrolytic copper enameled wire, insulated copper busbars, or copper tubes. An excitation winding is provided on the rotor to apply excitation current and establish the rotor magnetic field.

[0042] The twelve-phase generator 220 can be either a brushed synchronous motor or a brushless synchronous motor. In a brushed synchronous motor, external DC excitation current enters the rotor excitation winding through brushes and slip rings to establish the rotor magnetic field. In a brushless synchronous motor, a coaxial exciter is added. The stator winding of the exciter is powered by an external power source, and the AC current generated by the rotor winding is rectified by a rotating rectifier on the shaft before supplying the rotor excitation winding of the twelve-phase generator. The external excitation power supply of the brushless generator is significantly less than that of a brushed generator. Compared to a traditional three-phase generator in an AC / DC power system, the only difference in this application's multi-phase generator scheme is that it changes the traditional generator's six output terminals to 12-13, while the manufacturing costs are almost the same.

[0043] In one embodiment of this application, the twelve-phase armature winding adopts a star connection, and the neutral point of the star connection is grounded through a resistor to limit the short-circuit current generated by the twelve-phase armature winding or DC output terminal due to a ground fault.

[0044] Because the fault ground current is too large when the neutral point is directly grounded, the neutral point should not be directly grounded. Instead, a grounding resistor of a certain resistance value should be connected in series to avoid the fault current from damaging the winding insulation or rectifier devices and to improve the safety of the system under fault conditions.

[0045] The generator operates at a constant speed to obtain standard industrial frequency AC power; its constant voltage output is achieved by the automatic voltage regulator 250 described below. Regarding the winding architecture of the three-phase and twelve-phase generators, they can be configured with different electrical systems based on the same physical stator core structure. When the stator has twelve independent armature windings, each corresponding to one phase voltage, a twelve-phase generator can be constructed. Under the premise that the physical architecture remains unchanged, if the above twelve armature windings are divided into three winding groups, each containing four armature windings connected in series, and each winding group outputs one phase voltage, a three-phase generator can be constructed.

[0046] Figure 4 The diagram shows the phasor diagram of the output voltage of a twelve-phase generator in a star connection. The twelve-phase voltages U1~U12 are evenly distributed along the circumference, with a phase difference of 30° between adjacent phases, forming four independent three-phase voltage groups: U1, U5, and U9 in one group; U2, U6, and U10 in another group; U3, U7, and U11 in another group; and U4, U8, and U12 in yet another group. Any one of these groups can output three-phase electricity that meets the requirements on its own.

[0047] Figure 5 The diagram shows a vector comparison of induced voltages in three-phase and twelve-phase electricity. The diagram uses a basic two-pole generator for comparison. In the original twelve-phase winding, each phase voltage is a=b=c=d. When this twelve-phase generator is converted to a three-phase generator, these phase voltages are connected by a broken line to form a phase voltage u in the three-phase system. It is clear from the vector diagram that because the total length of the broken line is greater than the length of the straight line, the following expression applies: u < a+b+c+d Theoretically, the induced voltage utilization coefficient Ua of AC windings with different phase numbers can be expressed as: Ua = 2m×sin(180 / pm) In the formula, p represents the number of pole pairs of the motor, and m represents the number of phases of the AC power. Based on the above formula, the theoretical induced voltage utilization coefficients of a three-phase motor and a twelve-phase motor within the same physical architecture are calculated as follows: Ua3 = 2 × 3 × sin 60° ≈ 6 × 0.8660 ≈ 5.196 Ua12 = 2 × 12 × sin 15° ≈ 24 × 0.2588 ≈ 6.211 Under the same physical structure and winding current, for a two-pole motor, theoretically, the induced voltage utilization coefficient of the twelve-phase winding is significantly higher than that of the three-phase winding, allowing for an additional 19.53% of power output. However, this extra 19.53% power output is not generated by the generator itself; it requires additional mechanical energy input from the power unit. Therefore, in terms of generator efficiency, if a three-phase generator and a twelve-phase generator output the same amount of power, the proportional current output of the twelve-phase generator will definitely be less than that of the three-phase generator. In this case, the copper losses of the former will certainly be less than those of the latter. In other words, under the premise of outputting the same amount of power, the power generation efficiency of the twelve-phase generator will be significantly higher than that of the three-phase generator.

[0048] Therefore, based on the above-mentioned basic theory, the physical basis for achieving increased power output and improved power generation efficiency is to first improve the three-phase power generation system by replacing the three-phase generator with a twelve-phase generator. This is also the physical basis for achieving the technical objectives proposed in this application.

[0049] In one embodiment of this application, the system further includes a first fuse group and a second fuse group; each fuse in the first fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding positive rectifier branch of the rectifier; each fuse in the second fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding negative rectifier branch of the rectifier; each input terminal of the phase transformer is connected to the connection point between the first or second fuse group and the positive or negative rectifier branch of the rectifier.

[0050] Figure 6 The diagram shows the circuit diagram of the output circuit protection and rectifier of the twelve-phase generator. The twelve output terminals U1~U12 of the twelve-phase generator 220 are protected against overcurrent by fuses F1~F12 in the first fuse group and fuses F13~F24 in the second fuse group, and then output into AC and DC paths: AC output terminals E1~E12, and DC positive and negative output terminals rectified by rectifier 140. Each fuse in the first fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding positive rectifier branch of rectifier 140, i.e., F1~F12 in the diagram; each fuse in the second fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding negative rectifier branch of rectifier 140, i.e., F13~F24 in the diagram. Each input terminal of the phase transformer 300 is connected to the connection point between the first or second fuse group and the positive or negative rectifier branch of the rectifier.

[0051] By arranging two fuses, both AC circuit overload protection and positive / negative rectifier diode breakdown protection can be achieved simultaneously. F1-F12 provide dual protection against AC circuit overload and positive rectifier diode breakdown, while F13-F24 provide protection against negative rectifier diode breakdown. Even when one or two phases of the AC load disconnect, or one to four rectifier diodes experience breakdown short-circuit faults, the system can still maintain a power supply rate of over 80%, possessing high redundancy power supply capability. Its reliability and fault tolerance are far superior to traditional three-phase power systems.

[0052] In this embodiment, the rectifier 140 is a twelve-phase rectifier. The rectifier can be uncontrolled, semi-controlled, fully controlled, or bidirectional. Silicon diodes can be used as the rectifier diodes, which are the most economical, but they have a large forward voltage drop and significant heat generation. Therefore, fully controlled or semi-controlled rectifier devices such as MOSFETs, IGBTs, or SCRs can also be used to reduce conduction losses, improve rectification efficiency, and reduce harmonic effects. A set of RC protection circuits, consisting of a capacitor and a resistor connected in series, is connected in parallel across each rectifier diode to absorb high-voltage pulses in the rectifier and prevent the PN junction of the rectifier diode from being damaged by breakdown.

[0053] Although the cost of a twelve-phase rectifier is higher than that of a three-phase rectifier, the DC ripple and harmonic content of the twelve-phase rectifier output are much lower than those of a three-phase rectifier system, resulting in significantly improved voltage stability. This improves power quality while substantially reducing the size and cost of the filter unit. Furthermore, the 24 rectifier diodes share the rectification losses, resulting in lower heat load per diode, easier heat dissipation design, and longer device lifespan. The DC output from rectifier 140 is filtered by filter unit 150 and then connected to the DC bus via DC circuit breaker 161; the three-phase AC output from transformer 300 is connected to the AC bus via AC circuit breaker 162.

[0054] Depend on Figure 4 It is evident that this power system does not lack three-phase power; on the contrary, it contains four independent sets of three-phase power. The problem is that if only the winding terminals of any one set are drawn, only the AC power of that set of windings participates in the output, while the other three sets of windings do not participate. The actual AC output power of the generator is at most only 1 / 4 of the total power, resulting in extremely low winding utilization.

[0055] Multiphase generators offer significant advantages in improving DC power quality. However, since most land-based power grids and shipboard power systems currently use three-phase AC systems and motors are also predominantly three-phase AC motors, multiphase AC power is difficult to supply directly to external systems. Therefore, it is necessary to use a phase-changing transformer to transform the output of three-phase power from a single set of three-phase windings into the output of three-phase power from the entire multiphase windings through electromagnetic coupling.

[0056] The core problem this application aims to solve is how to output the full power AC of the entire generator winding from any set of three-phase ports. The solution is to use an electromagnetic coupling type phase-changing transformer with phase-changing function: through the new structure of the transformer, the four sets of AC terminals of the twelve-phase generator are electromagnetically coupled and connected from one of them, while the AC power output is shared by all windings.

[0057] Therefore, this application can also treat the twelve-phase television as a collection of two independent three-phase circuits: an odd-numbered three-phase circuit consisting of odd-numbered phase voltages (U1, U3, U5, U7, U9, U11) and an even-numbered three-phase circuit consisting of even-numbered phase voltages (U2, U4, U6, U8, U10, U12), and establish an electromagnetic link topology between the two circuits. Taking the odd-numbered circuit as an example, if U1-U7 are considered as phase A, U5-U11 as phase B, and U9-U3 as phase C, then it fully conforms to the definition of a three-phase circuit with a phase difference of 120°. The only difference from the traditional three-phase circuit is that the traditional connection uses the endpoints of each phase winding as the common terminal, while this application uses the center end of each phase winding as the common connection terminal.

[0058] This system uses an electromagnetically coupled phase transformer to convert twelve-phase electricity to three-phase electricity. Its core is to establish an electromagnetic link between the odd and even sets of three-phase voltages through phasor synthesis, so that all armature windings share the AC output power. The twelve-phase input terminals and the three-phase output terminals of the transformer are shared and not separated.

[0059] In one embodiment of this application, the transformer 300 has six iron cores and a primary winding wound on each iron core. The six iron cores are divided into a first iron core group and a second iron core group. The primary winding in each iron core group includes two sets of three-phase terminals. Each set of three-phase terminals is used to connect to one set of three-phase power in the twelve-phase AC power. The center terminals of each set of three-phase voltages are connected by a neutral point, and any set of three-phase terminals is used as an output terminal to output a full-power AC power. Two mutually electrically isolated windings are also wound on each iron core of the first iron core group. The secondary windings are separated and electromagnetically coupled to the primary windings on the same iron core. The primary windings on the first iron core group are connected to either an odd-numbered phase voltage or an even-numbered phase voltage, while the primary windings on the second iron core group are connected to the other. The center ends of all the primary windings are connected together. The odd-numbered phase voltages and the even-numbered phase voltages are obtained by dividing the twelve-phase AC power. The odd-numbered phase voltages include U1, U3, U5, U7, U9, and U11, and the even-numbered phase voltages include U2, U4, U6, U8, U10, and U12.

[0060] Furthermore, the primary winding wound on each iron core is connected to two phase voltages with opposite phases in the same phase voltage. The center end divides the primary winding into two half windings, each half winding corresponding to one of the two phase voltages with opposite phases. For example, the primary winding of the first iron core of the first iron core group is connected to U1 and U7. The center end divides the winding into a half winding corresponding to U1 and a half winding corresponding to U7, which are opposite in phase.

[0061] It should be noted that the winding direction and corresponding terminals of the two primary half-windings on each iron core should be determined according to the principle that the sum of the magnetic flux phasors of the three iron cores in the same iron core group is zero. That is, U1, U5, U9 (for odd-numbered groups) and U2, U6, U10 (for even-numbered groups) are taken as the positive directions of the magnetic flux of each iron core, so as to ensure the symmetry and balance of the three-phase magnetic circuits of each group.

[0062] In the first core group, the two secondary windings on each core correspond to the two phase voltages with opposite phases connected to the primary winding on the same core. In the first core group, the secondary windings on two different cores and corresponding to two phase voltages with a phase difference of 60° are connected in series in pairs. They are combined by phasor to generate three equivalent phase voltages in another set of phase voltages. Each equivalent phase voltage is then connected to the same-name terminal of the primary winding of the corresponding core in the second core group to establish an electrical connection between the phase voltages of the first core group and the second core group.

[0063] Figure 7 The diagram illustrates electromagnetic coupling phasor composition. Taking odd-numbered phase voltages U1 and U3 as examples, their phase difference is 60°. The even-numbered phase voltage U2 is located between U1 and U3, with a phase difference of 30° from both. Let the number of turns in the primary half-winding be n, and let the number of turns be... Two secondary windings of n (approximately 0.577n), corresponding to U1 and U3 respectively, are connected in series. The voltage phasor synthesis result is completely consistent with the amplitude and phase of U2. Connecting this synthesized voltage to the corresponding terminal of the primary winding of U2 in the second core group achieves the electrical connection between the odd-numbered and even-numbered phase windings. Similarly, by synthesizing U6 from U5 and U7, and U10 from U9 and U11, the electromagnetic connection between all odd- and even-numbered phase windings can be completed.

[0064] In one embodiment of this application, the number of turns in each secondary winding of the first core assembly is n times the number of turns in the corresponding primary half-winding. times.

[0065] The number of turns in each secondary winding of the first core assembly is equal to the number of turns n of the corresponding primary half-winding. This is approximately 0.577 times. Therefore, to ensure that the amplitude of the synthesized result is exactly equal to the phase voltage represented by the corresponding primary half-winding, the number of turns in each primary winding should be taken as n times the number of turns in the primary half-winding. Right now This turns ratio ensures that after the phasor synthesis of the voltages of two secondary windings with a 60° phase difference, the amplitude of the resulting equivalent phase voltage is completely matched with the amplitude of the corresponding phase voltage of the other group, ensuring that the voltages of each group are balanced after electrical connection, no circulating current is generated, and the stable operation of the transformer is guaranteed.

[0066] In one embodiment of this application, the phase transformer 300 includes a first transformer T1 and a second transformer T2; the first transformer includes three cores of the first core group, and the second transformer includes three cores of the second core group.

[0067] By splitting the phase transformer into two independent three-phase transformers, it can be adapted to the production process of conventional three-phase transformers, reducing manufacturing difficulty and cost. Furthermore, by setting the secondary winding only on one of the transformers, the winding structure and wiring complexity are simplified. It should be noted that in this embodiment, the secondary winding can be located on either T1 or T2; it is sufficient that one of the two transformers has six independent secondary windings while the other does not. The two can be interchanged according to the same principle.

[0068] Figure 8(a) shows the wiring diagram of an electromagnetically coupled phase-changing transformer. The first, second, and third core columns of the primary winding of transformer T1, corresponding to the first core group, are connected to six odd-numbered phase voltages: E1-E7, E5-E11, and E9-E3, respectively. From another perspective, the primary winding of transformer T1 includes two sets of three-phase terminals, connected to one set of three-phase electricity (E1-E5-E9) and another set of three-phase electricity (E7-E11-E3), with the center terminals of the two sets of three-phase voltages connected at the neutral point. The first, second, and third core columns of the primary winding of transformer T2, corresponding to the second core group, are connected to six even-numbered phase voltages: E2-E8, E6-E12, and E10-E4, respectively. From another perspective, the primary winding of transformer T2 also includes two sets of three-phase terminals, connected to one set of three-phase electricity (E2-E6-E10) and another set of three-phase electricity (E8-E12-E4). Any one of the four sets of three-phase terminals of transformers T1 and T2 can be used as an output terminal to output a full-power three-phase AC power.

[0069] The six secondary windings of T1 are connected in pairs to form E2, E6, and E10, which are then connected to the corresponding terminals of the primary winding of T2 to form a complete electromagnetic coupling link structure. Specifically, the secondary winding corresponding to E1 is connected in series with the secondary winding corresponding to E3 to form E2; the secondary winding corresponding to E5 is connected in series with the secondary winding corresponding to E7 to form E6; and the secondary winding corresponding to E9 is connected in series with the secondary winding corresponding to E11 to form E10.

[0070] From a physical perspective, the connection between T1 and T2 (including the common neutral line) completes the electrical coupling between two sets of odd and even three-phase electricity. However, the connection between two primary half-windings on the same iron core column (for example, between a set of three phases E1-E5-E9 and E7-E11-E3 on the same column, or between E2-E6-E10 and E8-E12-E4) is a magnetic field coupling. The two work together to complete the electromagnetic link coupling mechanism.

[0071] With the above structure, the output AC current connected to any set of three-phase windings is no longer powered by that single set of windings, but is powered equally by all twelve-phase windings. It can also be considered as realizing the phase transformation from twelve-phase electricity to three-phase electricity, while ensuring the full utilization of all windings of the generator.

[0072] The advantage of the electromagnetic coupling transformer scheme in this embodiment is that the input current in the transformer can actually cancel out the output current, just like the function of a traditional autotransformer. Moreover, the amount of current canceled out is higher than that of a traditional autotransformer, achieving a very high transformer efficiency and saving on the structural cost of the transformer.

[0073] In one embodiment of this application, although the transformer is highly efficient and low in cost, its only drawback is the lack of electrical isolation between the alternating current (AC) and direct current (DC). To solve the electrical isolation problem, a secondary winding can be wound on each core of the second core group. The secondary winding of the second core group includes a set of three-phase terminals, which are used as the output terminals to output the full-power AC current.

[0074] Figure 8(b) shows the wiring diagram of an electromagnetic coupling phase transformer with an electrically isolated winding. Based on the embodiment shown in Figure 8(a), Figure 8(b) adds a set of secondary three-phase windings to the second transformer T2, including a set of three-phase terminals A, B, and C. In this case, the three-phase AC power can be selectively output from the A, B, and C terminals of the secondary winding of the second transformer T2, thereby achieving electrical isolation between the AC output terminal and the DC output terminal in the system. The secondary three-phase winding of T2 can be either a star connection or a delta connection.

[0075] The above two output endpoint options can be selected according to actual needs.

[0076] In one embodiment of this application, both the first transformer and the second transformer are three-phase planar transformers. The three cores of the three-phase planar transformer are arranged side by side in the same plane and connected by a common magnetic yoke. Planar transformers have a simple structure and mature manufacturing process, making them suitable for small to medium power applications.

[0077] Small and medium power three-phase planar transformers typically employ a three-limb planar magnetic circuit structure. Therefore, the magnetic circuit on the middle core is short, while the magnetic circuits on the two outer limb cores are long. This asymmetrical magnetic circuit structure affects the symmetry of the three-phase electricity. Thus, high-power three-phase power transformers usually adopt a five-limb structure to achieve near-equivalence of the three-phase magnetic circuits. Since five-limb transformers are relatively expensive, a three-dimensional phase-changing transformer structure can be used to replace the planar phase-changing transformer.

[0078] In one embodiment of this application, both the first transformer and the second transformer are three-phase three-dimensional transformers. The three iron cores of the three-phase three-dimensional transformer are arranged in an equilateral triangle and inserted into the slots of the upper and lower magnetic yokes, respectively.

[0079] Figure 9 This diagram shows the split structure of the magnetic circuit of a laminated three-phase transformer. Figure 10 The diagram shows the split structure of the magnetic circuit of a hybrid three-phase transformer. The three-phase transformer arranges the three cores symmetrically in an equilateral triangle, ensuring that the three-phase magnetic circuit lengths are completely equal and the magnetic reluctance is the same. This eliminates the asymmetry defect of the planar transformer's magnetic circuit, allowing the three-phase output voltage and current to maintain a high degree of symmetry, resulting in better operational balance and making it suitable for high-power applications.

[0080] Three-phase three-dimensional transformers can be classified into laminated, wound, and hybrid types: In laminated transformers, both the core and yoke are made of laminated silicon steel sheets; in wound transformers, both the core and yoke are made of wound silicon steel strips; in hybrid transformers, one of the core and yoke is a laminated structure while the other is a wound structure, allowing for flexible selection based on processing conditions and performance requirements. In addition to using laminated silicon steel sheets or wound silicon steel strips, the 301 core can also be made of amorphous strip material.

[0081] Specifically, both T1 and T2 transformers have three core columns. Circular slots 321 are formed at the three vertices of an equilateral triangle on the inner surfaces of the upper yoke 310 and lower yoke 320. The diameter of the circular slots 321 is slightly larger than the outer diameter of the core column 301. During assembly, windings are first fitted onto the core column, and then both ends of the assembled core column are inserted into the circular slots 321 of the upper and lower yokes 310 and 320, respectively. A filler containing magnetic powder and adhesive is added to the slots to fill the assembly gaps between the core column and the yoke, reduce the magnetic resistance at the joints, and achieve bonding and fixation. Finally, the upper and lower yokes are pressed and fixed using a bracket, thus completing the assembly of a three-phase three-dimensional transformer. The three-phase magnetic circuit of this three-dimensional transformer is completely symmetrical, and its three-phase voltage and current also remain fully symmetrical, exhibiting higher balance performance than conventional planar transformers.

[0082] The three-dimensional transformer differs from the planar transformer only in its magnetic circuit structure; its winding structure and wiring rules are identical to those of Scheme 1. Terminals E1 and E7 are connected to the primary winding of the first core column in T1, terminals E5 and E11 are connected to the primary winding of the second core column in T1, and terminals E9 and E3 are connected to the primary winding of the third core column in T1. The six independent secondary windings are connected in pairs and combined using phasors to generate E2, E6, and E10, which are then connected to the corresponding terminals of the primary windings of the core columns in T2. ​​Phase voltages E2-E8, E6-E12, and E10-E4 are connected to the primary windings of the first, second, and third core columns of T2, respectively.

[0083] Both of the aforementioned embodiments require two transformers to form a transformer bank, while the following embodiment only requires one three-dimensional transformer to complete the phase-changing function. A major difference between three-dimensional transformers and planar transformers is that six-phase planar transformers are almost impossible to implement, while six-phase three-dimensional transformers are easy to implement. By simply increasing the structural dimensions of the yoke and adding three iron cores, one six-phase three-dimensional transformer can replace the function of two three-phase three-dimensional transformers, and it has a higher performance-price ratio.

[0084] In one embodiment of this application, the phase transformer 300 is a single six-phase three-dimensional transformer. The six iron cores are arranged at equal intervals along the circumference in a clockwise or counterclockwise direction and are respectively inserted into the slots of the upper and lower magnetic yokes. The arrangement order of the six iron cores along the circumference is consistent with the phase order of the phase voltages they are connected to, so that the primary winding connected to the odd-numbered phase voltages and the primary winding connected to the even-numbered phase voltages are arranged alternately along the circumference in the order of C1-C6.

[0085] Figure 11 A simplified diagram of the external structure of a six-phase three-dimensional transformer is shown. The six core columns, labeled C1 to C6, are evenly distributed along the circumference at 60° intervals in 12 symmetrical slots of the upper yoke 310 and lower yoke 320. Windings are mounted on the core columns, and the remaining assembly method is the same as that of a three-phase three-dimensional transformer. Core columns C1, C3, and C5 can be considered equivalent to transformer T1 in Scheme Two, while C2, C4, and C6 are equivalent to transformer T2 in Scheme Two. Using a single six-phase three-dimensional transformer can replace two three-phase transformers, reducing the number of devices and floor space required, resulting in a more compact structure. It also possesses the performance advantages of the symmetrical magnetic circuit of a three-dimensional transformer, offering higher cost-effectiveness.

[0086] The wiring rules are as follows: the E1 and E7 terminals of the generator winding output are connected to the primary winding of the C1 core column; the E5 and E11 terminals are connected to the primary winding of the C3 core column; and the E9 and E3 terminals are connected to the primary winding of the C5 core column. The secondary winding of C1 corresponding to E1 is connected in series with the secondary winding of C5 corresponding to E3 to form a phasor combination, and the combined voltage E2 is connected in parallel with the same-name terminal of the primary winding of C2; the secondary winding of C3 corresponding to E5 is connected in series with the secondary winding of C1 corresponding to E7 to form a phasor combination, and the combined voltage E6 is connected in parallel with the same-name terminal of the primary winding of C4; the secondary winding of C5 corresponding to E9 is connected in series with the secondary winding of C3 corresponding to E11 to form a phasor combination, and the combined voltage E10 is connected in parallel with the same-name terminal of the primary winding of C6, thereby realizing the electromagnetic connection between all phase windings. The primary windings connected to odd-numbered phase voltages and the primary windings connected to even-numbered phase voltages are arranged alternately along the circumference in the order of C1-C6. They must be arranged in phase order and cannot be arranged arbitrarily, otherwise the magnetic field phase will be reversed and disordered.

[0087] In one embodiment of this application, the system further includes a speed governor and an automatic voltage regulator 250; the speed governor is used to automatically adjust the power supply of the power unit 110 according to the speed change of the power unit 110 so that the power unit runs at a constant speed; the automatic voltage regulator 250 is used to adjust the excitation current in the excitation winding according to the deviation between the output voltage of the twelve-phase generator and a preset value so that the twelve-phase generator outputs a constant voltage.

[0088] Figure 12 The basic system structure diagram is shown. In the diagram, the power unit 110, the twelve-phase generator 220, together with the speed governor and the automatic voltage regulator 250, constitute the core of the system's power and power generation. The rear end is connected to the rectifier and filter branch composed of the rectifier 140 and the filter unit 150 and the phase transformer 300 branch, which output DC power and three-phase AC power through the DC circuit breaker 161 and the AC circuit breaker 162, respectively.

[0089] The controller 240 (shown as a CPU in the figure) is the basic control unit of the system. It is used to collect operating parameters such as voltage, current, and frequency of the generator 220 and AC and DC branches. After logical judgment, it outputs control signals to realize operation status monitoring, fault protection alarm, and remote opening and closing control of DC circuit breaker 161 and AC circuit breaker 162. The controller 240 can also send speed and voltage setting commands to the speed governor and automatic voltage regulator 250 to coordinate the constant speed operation of the power unit 110 and the constant voltage output of the generator 220.

[0090] The types of power engines 110 include steam engines, steam turbines, gas turbines, and internal combustion engines (diesel engines and gasoline engines), with diesel engines being the most commonly used in marine applications. Among them, gasoline engines have self-limiting speed capabilities due to the throttling effect of the air-fuel mixture and usually do not require a governor; diesel engines, because fuel injection and air intake are independent systems, must be equipped with a governor to maintain operational stability and prevent overspeeding or stalling at idle.

[0091] Speed ​​controllers include mechanical, hydraulic, pneumatic, and electronic control speed controllers, with the mechanical type being the typical structure, consisting of flyblocks, sliding sleeves, springs, and transmission components forming a closed-loop feedback system.

[0092] The speed governor senses the centrifugal force generated by the speed change through the flyweight assembly, drives the sliding sleeve to move axially and adjusts the position of the fuel injection pump rack in conjunction, thereby changing the fuel supply. When the load increases and the speed decreases, the centrifugal force decreases, and the spring pushes the sliding sleeve to increase the fuel supply to restore the speed. When the load decreases, the reverse adjustment is made to ensure that the engine maintains a stable speed under load fluctuations.

[0093] The Automatic Voltage Regulator (AVR) 250 collects the generator output voltage in real time and compares it with a preset value. When the voltage is too low, it increases the excitation current to raise the voltage; when the voltage is too high, it decreases the excitation current to lower the voltage. It can stabilize the output voltage within an error range of ±1%, and its voltage regulation range is typically ±10%. It has a fast response speed and ensures that the output power quality meets standards. The AVR 250 is widely used in diesel generator sets, synchronous generators, marine generator sets, and data center emergency backup power supplies. Common generator excitation methods include SHUNT shunt excitation and AREP auxiliary winding power supply, while PMG generators use permanent magnets to fix the magnetic field.

[0094] The system's basic protection employs a tiered protection system. The primary protection consists of fuse banks (see...). Figure 6 (F1~F24 in the model), secondary protection is the automatic circuit breaker 160. The circuit breaker works on the following principle: thermal tripping provides overload protection. When the current exceeds the rated value but does not reach the short-circuit level, the internal bimetallic strip is heated and bends, pushing the mechanism to disconnect the circuit. The larger the current, the faster the action. Therefore, its long-term overload current value is usually adjusted to be slightly lower than the rated fusing current value of the fuse. Magnetic tripping provides short-circuit protection. When the short-circuit current surges instantaneously, the electromagnetic coil generates a strong attraction, instantly pulling the trip unit to cut off the power supply. The reaction time is usually within 0.03 seconds. Some models are also equipped with an undervoltage trip unit, which automatically disconnects when the voltage drops severely or the power is cut off, preventing the equipment from starting unexpectedly when the voltage recovers. AC and DC circuit breakers cannot be mixed. AC circuit breakers 162 are available in single-phase / three-phase and one / two / three-phase configurations, while DC circuit breakers 161 are available in single-wire / double-wire configurations. After a circuit breaker fault is cleared, it can be manually reset and supports remote intelligent control of opening and closing. Compared with fuses, it does not require replacement of the fuse element and has no consumable losses.

[0095] In one embodiment of this application, the system supports the parallel operation of multiple generators to adapt to larger capacity load requirements and achieve unit redundancy backup. Since the system uses both AC and DC power systems, its parallel operation is more complex than that of a simple AC power system or DC power system. Therefore, the AC and DC parts need to be connected in parallel according to the following conditions.

[0096] When the DC section is connected in parallel, the output voltage of the generator to be connected to the grid should be adjusted to be slightly higher than the DC bus voltage. Then, the DC circuit breaker 161 can be manually or automatically started to close the DC bus and output DC power. It is necessary to avoid the voltage of the generator to be connected to the grid being lower than the bus voltage to prevent backflow of electrical energy from affecting the normal operation of the power unit.

[0097] Parallel operation of the AC section requires four conditions to be met: voltage, frequency, phase, and phase sequence must be consistent. This is an absolute prerequisite; if the phase sequence is incorrect, closing the circuit is equivalent to a three-phase short circuit, causing serious equipment damage. Voltage must be equal, with the effective value of the output voltage deviating from the grid voltage by no more than ±5%. Voltage discrepancies will generate reactive circulating current, leading to winding overheating. Frequency must be the same, with the frequency deviation controlled within 0.2~0.5Hz. Frequency differences will cause beat current and shaft torque fluctuations, resulting in unit vibration. Phase must be the same, with the phase difference between corresponding phase voltages approaching zero at the moment of grid connection. Excessive phase deviation will generate a huge transient inrush current. By precisely controlling the parallel operation conditions, grid inrush currents can be avoided, ensuring the safety of the unit and the grid.

[0098] In another embodiment of this application, the system can be configured with power plant automation equipment to achieve a higher level of automated management. Figure 13 This diagram shows the structure of an AC / DC power system controlled by a Power Management System (PMS).

[0099] In this embodiment, Figure 12 The controller 240 can be replaced by the power plant automation equipment 170. The power plant automation equipment 170 realizes the automated operation of power generation, distribution and load management through its internal PMS, ensuring the continuity, reliability and power quality of power supply. Its core functions include: 1. Automatic start-stop and standby management of generator sets: Real-time monitoring of load changes; when the operating unit is overloaded, malfunctions, or the load exceeds the set threshold, the standby unit is automatically started; when the load drops below the economic operating range, the redundant units are automatically disconnected and stopped to achieve energy-saving operation; under low load conditions, one unit is kept running while the other units are in hot standby status to ensure that they can be connected to the grid at any time.

[0100] 2. Automatic Synchronization and Parallelization: Automatically detects the voltage, frequency, and phase of the generator to be paralleled, adjusts the frequency and voltage to meet the paralleling conditions, and issues a closing command at the optimal time; when the unit stops or fails, it automatically transfers the load and disconnects the main switch to prevent reverse power from damaging the equipment.

[0101] 3. Load distribution and frequency / voltage stability control: The speed governor automatically adjusts the prime mover speed to achieve uniform distribution of active load among units and maintain constant grid frequency; the excitation current is controlled by the automatic voltage regulator to achieve reasonable distribution of reactive load and stabilize grid voltage.

[0102] 4. System Protection and Fault Handling: The system performs rapid detection and protection actions against faults such as overload, short circuit, reverse power, undervoltage, and loss of excitation; in the event of a system-wide power failure, the system automatically starts key units in priority order to restore power supply to important loads in sequence; it collects data such as voltage, current, power, and frequency in real time and supports historical data storage and fault diagnosis.

[0103] Modern power plant automation often adopts distributed control systems (DCS) or PLC / fieldbus-based architectures. Some advanced systems have been integrated into integrated power systems (IPS) to support DC grid connection and intelligent energy dispatch.

[0104] Another aspect of this application provides an AC / DC power supply method based on a twelve-phase generator, applicable to a system as described in any of the preceding claims, the method comprising steps S11 to S14.

[0105] In step S11, the power unit drives the twelve-phase generator at a constant speed and supplies excitation current to the excitation winding on the rotor, so that the twelve-phase armature winding outputs a constant frequency and constant voltage twelve-phase alternating current.

[0106] Specifically, the power supply of the generator is adjusted by the speed governor to maintain the generator's constant speed operation; the excitation current is adjusted by the automatic voltage regulator to stabilize the generator output voltage at a preset value, thereby outputting constant frequency and constant voltage twelve-phase AC power that conforms to the power frequency standard.

[0107] Step S12: The output terminals of the twelve-phase armature winding are divided into two parallel paths. The twelve-phase AC power output from one path is rectified by the rectifier and filtered by the filter unit to output DC power.

[0108] After the twelve-phase AC power is rectified by the multiphase rectifier, the DC voltage ripple and harmonic content are much lower than those of the three-phase rectifier system. The voltage stability is high. With the help of the filter unit, it can output high-quality DC power and connect to the DC bus through the DC circuit breaker. It is suitable for DC loads such as precision electronic equipment and energy storage devices.

[0109] Step S13: Input the twelve-phase AC power output from the other path into the phase transformer. Divide the phase voltages of the twelve-phase AC power into two phase voltage groups according to phase sequence. By combining the phasors of two adjacent phase voltages in the same group within the phase transformer, an equivalent phase voltage in the other group is generated. The generated equivalent phase voltage is electrically connected to the corresponding phase voltage in the other group to establish an electrical connection between the windings corresponding to the two groups of phase voltages. Combined with the magnetic field coupling within the phase transformer, all windings of the twelve-phase armature winding are electromagnetically linked and coupled. Therefore, even if only one set of three-phase windings is connected to the output terminal, all generator windings can still share the AC power output.

[0110] The odd and even windings are electrically connected through phasor synthesis, and there is magnetic field coupling between the two primary half-windings with opposite phases on the same iron core column. The two work together to connect the four sets of three-phase windings of the twelve-phase armature winding into a whole both electrically and magnetically. Therefore, no matter which set of three-phase ports the AC load current is drawn from, the ampere-turns corresponding to the current are equally shared by all twelve armature windings according to the phase relationship, rather than being borne by only the set of windings connected.

[0111] Step S14: The three-phase AC power shared by the entire winding is output from the output terminal of the transformer. The output terminal can be any set of three-phase terminals of the primary winding to achieve input and output terminal sharing, or a set of three-phase terminals of the secondary winding of the second core group to achieve electrical isolation.

[0112] There are two implementation methods for the output terminals of the phase-changing transformer, which can be selected according to actual needs. In the first implementation, the output terminals are any three-phase terminals of the primary winding. Since the primary winding is connected to both the twelve-phase AC input and the three-phase AC output, the input and output terminals physically share the same three-phase terminals, thus achieving input-output terminal sharing. This method eliminates the secondary output winding, making the structure simpler. Furthermore, since the input and output currents are in opposite directions and cancel each other out in the same winding, its principle is similar to the current cancellation effect of a traditional autotransformer. The actual current flowing in the winding is only the difference between the input and output currents, effectively reducing winding copper losses and achieving high power efficiency and minimal hardware cost. In the second implementation, the output terminals are a set of three-phase terminals of the secondary winding of the second core group. In this case, the twelve-phase AC power is input through the primary winding, electromagnetically coupled, and output through the secondary winding. The input and output circuits are electrically isolated from each other, thus achieving electrical isolation. In this mode, there is no direct electrical connection between the output side and the input side, which helps to isolate the fault propagation path under fault conditions and improve the power supply safety of the system.

[0113] Although the two implementation methods differ in the selection of the output endpoints and whether endpoint sharing or electrical isolation is implemented, both are based on the electromagnetic link and magnetic field coupling mechanism between the first and second core groups inside the transformer, enabling all windings of the twelve-phase armature windings to participate in power transmission. Only one set of three-phase output endpoint interfaces is needed to output the generator's full-power three-phase AC power. The interface form is compatible with existing three-phase power supply systems, and all windings share the power, resulting in high winding utilization. This three-phase AC power is connected to the system's AC bus via an AC circuit breaker.

[0114] In one embodiment of this application, the two phase voltage groups of the twelve-phase alternating current are respectively an odd-numbered phase voltage group composed of odd-numbered phase voltages and an even-numbered phase voltage group composed of even-numbered phase voltages, and the phase difference between the two adjacent phase voltages is 60°; the phasor synthesis is performed by the phase transformer corresponding to the two adjacent phase voltages, and the number of turns is the number of turns n of the primary half-winding. The two secondary windings are connected in series to achieve the same value, and the phase difference between the generated equivalent phase voltage and the two adjacent phase voltages is 30°.

[0115] This phase and turns matching design ensures that the amplitude and phase of the synthesized voltage are completely consistent with the target phase voltage, achieving a deviation-free electrical connection and ensuring the stability and symmetry of the system operation.

[0116] This technical solution has completed the fabrication and testing of an experimental prototype, which consists of a twelve-phase generator, an electromagnetic coupling phase transformer, and basic protection devices. The generator is a 12-phase, 4-pole constant-frequency, constant-voltage brushless AC rectifier generator with a rated power of 80kW, a rated speed of 1500rpm, a rated phase voltage of 266V, and an air-cooled structure. The phase transformer is a three-phase planar structure with a rated power of 80kVA, a rated input of 266V twelve-phase power, and a rated output of 380V three-phase power, using a Y / Y connection and dry-type air-cooled heat dissipation. The basic protection device adopts a double fuse group structure.

[0117] Table 1 shows the test voltage meters for the generator. The test results show that the twelve-phase output voltage has good symmetry, and the voltage between each phase meets the design expectation of a 30° phase difference, verifying the correctness of the twelve-phase generator winding design and the stability of the output characteristics. All data in the table are measured values. Due to the influence of instrument accuracy and contact resistance at the measuring points, there may be a single-digit deviation between the forward and reverse measurements of the same phase voltage, which is within the normal measurement error range.

[0118] Table 1. Test Voltage Table for Twelve-Phase Generator

[0119] The core advantages of a twelve-phase rectifier generator can be summarized as follows: 1. Increased power density: The twelve-phase windings are more scientifically and rationally distributed in the stator space, and can output more power with the same volume and weight, significantly improving energy efficiency and saving installation space.

[0120] 2. Power quality optimization: After multi-phase rectification, the DC voltage ripple is small and the ripple coefficient is low. The voltage smoothness is better than that of traditional three-phase rectification systems, which can reduce the interference of voltage fluctuations on precision electronic equipment (such as medical equipment and data center equipment).

[0121] 3. Enhanced anti-interference capability: The twelve-phase system generates high harmonic orders and small amplitudes, making electromagnetic interference easier to suppress through filters and improving the overall electromagnetic compatibility of the system.

[0122] 4. High operational stability: The multiphase structure has natural redundancy characteristics, and can still maintain operation in the event of a single-phase or partial failure, accompanied only by a decrease in power rather than a complete power outage. It has strong fault tolerance, which is especially important in fields where interruption is not possible, such as aerospace and continuous industrial production lines.

[0123] In summary, the AC / DC power system and power supply method based on a twelve-phase generator provided in this application achieves multiple technological improvements through the structural design of a single twelve-phase armature winding combined with an electromagnetically coupled phase-changing transformer: First, it improves the generator's output power and operating efficiency. The induced voltage utilization coefficient of the twelve-phase winding is higher than that of the traditional three-phase winding, and it can output higher power under the same physical structure; the single winding structure saves space in the motor slots and increases power density; and when outputting the same power, the winding current is smaller, the copper loss is lower, and the power generation efficiency is higher.

[0124] Secondly, it enhances the system's versatility. The AC / DC output power ratio is not limited by the preset winding structure and can be flexibly adjusted according to load requirements. It is suitable for scenarios with a fixed AC / DC load ratio as well as scenarios with dynamic changes in the load ratio during power system transitions. It can be widely used in various fields such as ships, mobile power stations, and data centers.

[0125] Third, it improves system reliability and redundancy. The system uses traditional electromagnetic equipment such as generators and transformers as its core, reducing the amount of fragile power electronic components. The equipment has strong impact resistance and long service life. The design of multi-phase windings and double fuse groups brings natural redundancy, and can still maintain a high proportion of power supply under partial faults. The operational reliability is far higher than that of traditional three-phase systems.

[0126] Fourth, it improves technical and economic efficiency. The solution is based on mature motor and transformer manufacturing processes, and achieves performance improvement only through innovation in winding structure and wiring topology. Manufacturing costs are controllable, the input-output ratio is high, and it has good engineering application value.

[0127] The reason why the apparatus and method of this application have a wide range of applications is fundamentally because the application of electrical energy has penetrated into all aspects of human social activities and life. Specifically, AC / DC power systems can replace shipboard DC power systems, especially advanced shipboard medium-voltage DC integrated power systems, as well as aircraft dual-electric systems in the aviation field. In the field of marine machinery, even in the existing traditional AC power systems, as long as photovoltaic power generation, power battery energy storage, and other equipment are equipped or planned to be added, DC equipment needs to be superimposed on the original AC power system. Therefore, AC / DC power systems are also very suitable for replacing the original AC power systems, which will better meet the power supply needs of different loads and give full play to the advantages of dual-electric systems.

[0128] In addition, this system is applicable to applications requiring high-quality and efficient direct current in fields such as wind power generation, wind and solar power, electrolytic plating, electrochemistry, and hydrogen and chlorine production.

[0129] In today's AI era, the power supply field of computing centers, especially supercomputing centers, has strict requirements for power quality. The general power supply ratio of these centers is 2 / 3 low-voltage DC power for computer systems and the remaining 1 / 3 AC power for high-efficiency heat dissipation devices. Therefore, this AC / DC power system can not only be used as emergency power supply for the center, but also be combined with SST as the main power supply for the center.

[0130] This application also provides a computer-readable medium having computer instructions stored thereon, which can be executed by a processor to implement an AC / DC power supply method based on a twelve-phase generator as described above.

[0131] When an AC / DC power supply method based on a twelve-phase generator is implemented as a computer program, it can also be stored as an article of manufacture in a computer-readable storage medium. For example, a computer-readable storage medium may include, but is not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic stripes), optical discs (e.g., compact discs (CDs), digital multifunction discs (DVDs)), smart cards, and flash memory devices (e.g., electrically erasable programmable read-only memory (EPROM), cards, sticks, key drives). Furthermore, the various storage media described herein can represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media (and / or storage media) capable of storing, containing, and / or carrying code and / or instructions and / or data.

[0132] It should be understood that the embodiments described above are merely illustrative. The embodiments described herein may be implemented in hardware, software, firmware, middleware, microcode, or any combination thereof. For hardware implementation, the processor may be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and / or other electronic units designed to perform the functions described herein, or combinations thereof.

[0133] Some aspects of this application can be executed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The aforementioned hardware or software may be referred to as a "data block," "module," "engine," "unit," "component," or "system." The processor may be one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. Furthermore, aspects of this application may manifest as computer products residing in one or more computer-readable media, including computer-readable program code. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic tapes, etc.), optical discs (e.g., compressed CDs, digital multifunction DVDs, etc.), smart cards, and flash memory devices (e.g., cards, sticks, key drives, etc.).

[0134] A computer-readable medium may contain a propagated data signal containing computer program code, for example, on baseband or as part of a carrier wave. This propagated signal may take various forms, including electromagnetic, optical, and so on, or suitable combinations thereof. A computer-readable medium can be any computer-readable medium other than a computer-readable storage medium, which can be connected to an instruction execution system, apparatus, or device to enable communication, propagation, or transmission of a program for use. The program code located on the computer-readable medium can be propagated through any suitable medium, including radio, cable, fiber optic cable, radio frequency signals, or similar media, or any combination of the above media.

[0135] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0136] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0137] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0138] This application may include other examples that would occur to those skilled in the art. Such other examples would fall within the scope of protection of this application if they have structural units that are exactly the same as the wording of this claim, or if they include equivalent structural units that have a non-substantial difference from the wording of this claim.

Claims

1. An AC / DC power system based on a twelve-phase generator, comprising a power unit and a twelve-phase generator, wherein the twelve-phase generator is a brushed synchronous motor or a brushless synchronous motor, and the power unit is used to drive the twelve-phase generator to output twelve-phase AC power, characterized in that, The system also includes a rectifier, a filter unit, and a phase transformer; The stator of the twelve-phase generator is uniformly arranged with a single set of twelve-phase armature windings along the circumference, and the rotor is provided with an excitation winding for passing excitation current to establish a rotor magnetic field. The output terminals of the twelve-phase armature winding are divided into two parallel paths. One path is connected to the rectifier and the filter unit in sequence to output DC power. Another path is connected to the phase transformer, which converts the twelve-phase AC power containing four sets of three-phase electricity into a single full-power AC output through a set of three-phase terminals.

2. The system according to claim 1, characterized in that, The twelve-phase armature winding adopts a star connection, and the neutral point of the star connection is grounded through a resistor to limit the short-circuit current generated by the twelve-phase armature winding or DC output terminal due to a ground fault.

3. The system according to claim 1, characterized in that, The transformer has six iron cores and a primary winding wound on each iron core. The six iron cores are divided into a first iron core group and a second iron core group. The primary winding in each iron core group includes two sets of three-phase terminals. Each set of three-phase terminals is used to connect to one set of three-phase power in the twelve-phase AC power. The center terminals of each set of three-phase voltages are connected by a neutral point, and any set of three-phase terminals is used as an output terminal to output a full-power AC power. Each core of the first core group is also wound with two electrically isolated secondary windings, which are electromagnetically coupled to the primary windings on the same core. The primary winding on the first core group is connected to either an odd-numbered phase voltage or an even-numbered phase voltage, while the primary winding on the second core group is connected to the other. The center ends of all the primary windings are connected together. The odd-numbered phase voltage and the even-numbered phase voltage are obtained by dividing the twelve-phase alternating current.

4. The system according to claim 3, characterized in that, Each core of the second core assembly is also wound with a secondary winding, which includes a set of three-phase terminals that are used as the output terminals to output the full-power alternating current.

5. The system according to claim 3 or 4, characterized in that, The primary winding wound on each iron core is connected to two phase voltages with opposite phases in the same phase voltage. The center end divides the primary winding into two half windings, each half winding corresponding to one of the two phase voltages with opposite phases. The two secondary windings on each core in the first core group correspond to the two phase voltages with opposite phases connected to the primary winding on the same core. In the first core group, the secondary windings of two phase voltages located on two different cores and corresponding to a phase difference of 60° are connected in series. The three equivalent phase voltages in another set of phase voltages are generated by phasor synthesis. Each of the equivalent phase voltages is connected to the same-name terminal of the primary winding of the corresponding core in the second core group to establish an electrical connection between the phase voltages of the first core group and the second core group.

6. The system according to claim 5, characterized in that, The number of turns in each secondary winding of the first core assembly is equal to the number of turns n of the corresponding primary half-winding. times.

7. The system according to claim 5, characterized in that, The phase-changing transformer includes a first transformer and a second transformer; The first transformer includes three cores of the first core group, and the second transformer includes three cores of the second core group.

8. The system according to claim 7, characterized in that, Both the first transformer and the second transformer are three-phase planar transformers. The three cores of the three-phase planar transformer are arranged side by side in the same plane and connected by a common magnetic yoke.

9. The system according to claim 7, characterized in that, Both the first transformer and the second transformer are three-phase three-dimensional transformers. The three iron cores of the three-phase three-dimensional transformer are arranged in an equilateral triangle and inserted into the slots of the upper and lower magnetic yokes, respectively.

10. The system according to claim 5, characterized in that, The transformer is a single six-phase three-dimensional transformer. The six iron cores are arranged at equal intervals along the circumference in a clockwise or counterclockwise direction and are respectively inserted into the slots of the upper and lower magnetic yokes. The arrangement of the six iron cores along the circumference is consistent with the phase sequence of the phase voltages they are connected to, such that the primary windings connected to odd-numbered phase voltages and the primary windings connected to even-numbered phase voltages are arranged alternately along the circumference in the order C1-C6.

11. The system according to claim 1, characterized in that, The system also includes a first fuse group and a second fuse group; Each fuse in the first fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding positive terminal rectifier branch of the rectifier. Each fuse in the second fuse group is connected in series between each output terminal of the twelve-phase armature winding and the corresponding negative rectifier branch of the rectifier; Each input terminal of the phase transformer is connected to the connection point between the first or second fuse group and the positive or negative rectifier branch of the rectifier.

12. The system according to claim 1, characterized in that, The system also includes a speed controller and an automatic voltage regulator; The speed regulator is used to automatically adjust the power supply of the power unit according to the speed change of the power unit, so as to make the power unit run at a constant speed; The automatic voltage regulator is used to adjust the excitation current in the excitation winding according to the deviation between the output voltage of the twelve-phase generator and a preset value, so as to make the twelve-phase generator output a constant voltage.

13. A method for supplying AC / DC power based on a twelve-phase generator, applied to the system as described in any one of claims 1 to 12, characterized in that, The method includes: The power unit drives the twelve-phase generator at a constant speed and supplies excitation current to the excitation winding on the rotor, so that the twelve-phase armature winding outputs a constant frequency and constant voltage twelve-phase alternating current. The output terminals of the twelve-phase armature winding are divided into two parallel paths. The twelve-phase AC power output from one path is rectified by the rectifier and filtered by the filter unit to output DC power. The twelve-phase AC power output from another path is input into the phase transformer. The phase voltages of the twelve-phase AC power are divided into two phase voltage groups according to the phase sequence. By combining the phasors of two adjacent phase voltages in the same group within the phase transformer, an equivalent phase voltage in the other group is generated. The generated equivalent phase voltage is electrically connected to the corresponding phase voltage in the other group to establish an electrical connection between the windings corresponding to the two groups of phase voltages. Combined with the magnetic field coupling within the phase transformer, all windings of the twelve-phase armature winding are electromagnetically linked and electromagnetically coupled. Therefore, even if only one set of three-phase windings is connected to the output terminal, all generator windings can still share the AC power output. The output terminal of the transformer outputs three-phase AC power shared by the entire winding. The output terminal can be any set of three-phase terminals of the primary winding to achieve input and output terminal sharing, or a set of three-phase terminals of the secondary winding of the second core group to achieve electrical isolation.

14. The method according to claim 13, characterized in that, The twelve-phase alternating current has two phase voltage groups, namely an odd-numbered phase voltage group composed of odd-numbered phase voltages and an even-numbered phase voltage group composed of even-numbered phase voltages, and the phase difference between the two adjacent phase voltages is 60°. The phasor synthesis is performed by the transformer, where each phase corresponds to one of the two adjacent phase voltages and has a number of turns corresponding to the number of turns n of the primary half-winding. The two secondary windings are connected in series to achieve the same value, and the phase difference between the generated equivalent phase voltage and the two adjacent phase voltages is 30°.

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