Δ-Δ Phase-Shifting Transformer with 16-Multiple-Winding Output and Power Supply and Distribution System

Abstract

The Δ-Δ phase-shifting transformer with a 16-multiple winding output and the power supply and distribution system. The high-voltage side winding is connected in a Δ shape, and the low-voltage side winding includes at least one small group winding. Each small group winding includes 16 three-phase low-voltage phase-shifting windings connected in an extended Δ connection. Each phase coil of the low-voltage phase-shifting winding is composed of a basic coil D1 and an extended coil Y1. The basic coil D1 is used to construct the triangular side of the phase-shifting winding, and the extended coil Y1 is used to construct the triangular extended side of the phase-shifting winding. It is characterized in that the theoretical phase angle distribution of each low-voltage phase-shifting winding of each small group winding and the turn combination configuration of the basic coil D1 and the extended coil Y1 in each phase coil of windings with different phases are arranged according to the optimized combination data, constructing a Δ-Δ phase-shifting transformer with a 16-multiple winding output, which can obtain a relatively optimized harmonic elimination effect and a relatively balanced output waveform, achieving harmonic elimination quality and standards that are not only relatively advantageous but also predictable and stable.

Description

Technical Field

[0001] The present invention relates to a phase-shifting transformer and a power supply and distribution system, and particularly to a Δ-Δ phase-shifting transformer with a 16-fold winding output containing an extension coil and a power supply and distribution system for a data center. Background Art

[0002] With the development of the communication industry and the cloud computing industry, the amount of data has been continuously climbing. There is great potential in the construction of data centers, and higher requirements are placed on the product performance and economic cost of transformers applied in data centers. The electrical load characteristics of the data center include a large number of DC electrical loads, such as server hosts including UPS modules.

[0003] In the DC power distribution cabinet of the data center, a large number of IGBT rectifier modules are configured to rectify the alternating current input by the low-voltage phase-shifting winding of the transformer into direct current. The phase of the low-voltage phase-shifting winding is preferably adapted to the triggering phase of the IGBT rectifier circuit. The phase-shifting output with a multi-winding configuration can greatly eliminate harmonics (commonly known as harmonic elimination). For the above purpose, the patent application No. 201520526746.6, named "Oil-immersed 54-pulse frequency conversion transformer for high-power high-voltage frequency conversion device", discloses that its high voltage adopts a Δ-connected three-phase primary winding, and the low voltage adopts a multi-phase output winding with a extended delta connection. Its characteristics are that the low-voltage winding is divided into three large groups, and each large group includes 9 low-voltage phase-shifting windings, and their phase-shifting angles are +26.67°, +20°, +13.33°, +6.67°, 0°, -6.67°, -13.33°, -20°, -26.67° respectively, and the phase difference between each low-voltage phase-shifting winding is 6.67°; each phase is composed of several power units connected in series, and the adjacent three-phase low-voltage outputs are mutually different by 6.67°. These 9 low-voltage phase-shifting windings are triggered by thyristor IGBTs controlled by three-phase different timing pulses to obtain 27 positive and negative pulses each; the high-voltage winding is also divided into three large groups, and both the high-voltage winding and the low-voltage winding adopt a pancake coil structure; each phase of the secondary side outputs 27 windings, and there are 81 windings in total for three phases. The low-voltage bushings are led out from the side wall of the oil tank, with a total of 81 bushings. The technical solutions for harmonic elimination using a multi-winding extension coil Y1, including the above-mentioned prior art, have the following problems in actual manufacturing:

[0004] 1. Since the voltage levels of the high-voltage power systems of each data center may be different, if the transformer is redesigned to adapt to such different input voltages, the workload will obviously increase greatly, the delivery period will be delayed, and the manufacturing cost will increase;

[0005] 2. Redesigning the transformer to adapt to different voltage levels and the specified requirements of users results in different phase-shifting angles of the secondary side, different filtering effects, and poor product consistency;

[0006] 3. To redesign the transformer to adapt to different voltage levels, the inconsistent number of turns results in a slow development cycle of the new product project, affecting the actual commissioning of the product. Summary of the Invention

[0007] For a low-voltage multi-winding phase-shifting transformer, it is not only to adapt to a large number of IGBT rectifier loads, but also to reduce the harmonic interference to the power system. However, how to design a Δ-Δ phase-shifting transformer with a 16-multiple winding output to make it have generality in design and manufacturing, or to have relatively optimized harmonic elimination performance when adapting to high-voltage systems of various different voltage levels, is the problem that the present invention attempts to solve. Based on this, the present invention proposes a Δ-Δ phase-shifting transformer with a 16-multiple winding output, the high-voltage end winding adopts a Δ connection method, the low-voltage end winding includes at least one group winding, and each of the group windings includes 16 three-phase low-voltage phase-shifting windings adopting an extended Δ connection method; each phase coil of the low-voltage phase-shifting winding is composed of a basic coil D1 and an extended coil Y1, the basic coil D1 is used to construct the triangular side of the phase-shifting winding, and the extended coil Y1 is used to construct the triangular extended side of the phase-shifting winding; it is characterized in that the theoretical phase angle distribution of each low-voltage phase-shifting winding of each group winding and the turn number combination configuration of the basic coil D1 and the extended coil Y1 in each phase coil of different phase windings are arranged according to the data of any one of the combinations 1 or 2 listed in the following table;

[0008]

[0009] Among them, when the number of turns of the extended coil Y1 is zero, the low-voltage phase-shifting winding is all composed of the basic coil D1 to form a winding with a Δ connection method, and when the number of turns of the basic coil D1 is zero, the low-voltage phase-shifting winding is all composed of the extended coil Y1 to form a winding with a Y connection method; when the phase angle A1 is greater than 30°, it means that the low-voltage phase-shifting winding is arranged in a positive phase, and when the phase angle A1 is less than 30°, it means that the low-voltage phase-shifting winding is arranged in a reverse phase.

[0010] Among them, after rectification, each coil outputs 2 high and low peak pulse outputs, and the output pulse number of the Δ-Δ phase-shifting transformer with a 16-multiple winding output is 16×6×n (n = 1, 2, 3 or 4). That is to say, according to the structure of the present invention, n group windings can be designed. In theoretical design, n can continue to be enlarged, but in actual production, generally n is taken within 4, which is sufficient for the on-site use requirements.

[0011] Among them, the three coils of each low-voltage winding are connected in a extended side triangle. In theory, each winding or each coil contains a basic coil D1 and an extended coil Y1. The turn combinations of the basic coil D1 and the extended coil Y1 in each phase coil of the 16 low-voltage phase-shifting windings in different phase windings are configured according to the data in the above table. It should be noted that the basic coil D1 constitutes the basic triangular side of the extended side triangle, and the extended coil Y1 constitutes the extended side of the extended side triangle. When the number of turns of the basic coil D1 is zero, the three extended coils Y1 are connected in a Y shape in a special case. When the number of turns of the extended coil Y1 is zero, the three basic coils D1 are connected in a standard △ shape in a special case.

[0012] According to the above technical solution, its beneficial technical effect is that a △-△ phase-shifting transformer with a 16-fold winding output is constructed based on the optimized data in the above table, and relatively optimized harmonic elimination effect and relatively balanced output waveform can be obtained. When there is a need for a △-△ phase-shifting transformer with a 16-fold winding output, only the number of turns of the primary winding needs to be adaptively adjusted according to the different input voltage levels or output voltage levels, and other indicators such as the wire diameter of the coil or the number of the small group windings are adjusted according to the different output powers, so as to achieve relatively superior harmonic elimination quality and standards, and also have predictability and stability.

[0013] Secondly, the present invention also provides a power supply and distribution system applying the above △-△ phase-shifting transformer with a 16-fold winding output, including the phase-shifting transformer, a high-voltage power distribution cabinet configured on the input side of the phase-shifting transformer, and a DC load power distribution cabinet configured on the output side of the phase-shifting transformer. The outgoing line end of the high-voltage power distribution cabinet is electrically connected to the three-phase high-voltage winding of the phase-shifting transformer, and the low-voltage phase-shifting winding of the phase-shifting transformer is electrically connected to the incoming line end of the DC load power distribution cabinet.

[0014] Due to the above advantages and characteristics of the present invention, it can be applied to the products of △-△ phase-shifting transformers with a 16-fold winding output and power supply and distribution systems. Brief Description of the Drawings

[0015] Attached Figure 1 , is the wiring schematic diagram of the phase-shifting transformer 100 applying the present invention, Figure 1 The secondary low-voltage winding in it contains four extended side triangle windings of (a), (b), (c), and (d);

[0016] Attached Figure 2 , is the electrical structure schematic diagram of the power supply and distribution system;

[0017] Attached Figure 3 , is the layout structure schematic diagram of the power supply and distribution system. Detailed Embodiments

[0018] The following will describe the specific implementation structure of the Δ-Δ phase-shifting transformer product 100 with a 16-multiple winding output and the power supply and distribution system in conjunction with the accompanying drawings. The Δ-Δ phase-shifting transformer 100 with a 16-multiple winding output includes three iron core columns, on which three-phase high-voltage end windings and three-phase low-voltage end windings are arranged. The voltage level of the high-voltage end winding is 10 kV. Each phase coil of the high-voltage end winding is respectively installed on the three iron core columns. The high-voltage end winding is connected in Δ shape and connected to the 10 kV input system. The low-voltage end winding includes 32 low-voltage phase-shifting windings. Among them, every 16 low-voltage phase-shifting windings are bundled together as a group winding to form a winding unit, and 2 such group windings or winding units are arranged vertically on the iron core column. In order to measure the operating temperatures in the high-voltage end winding and the low-voltage end winding, temperature probes are respectively arranged in them to detect and output the temperature signals of the coils to the central controller.

[0019] The 16 low-voltage phase-shifting windings of one group winding are constructed in a way of mixing the basic coil D1 and the extended coil Y1. The basic coil D1 is used to construct the triangular side of the phase-shifting winding, and the extended coil Y1 is used to construct the triangular extended side of the phase-shifting winding.

[0020] As Figure 1 shown, the three coils of each low-voltage phase-shifting winding are connected in a zigzag delta connection. Each low-voltage phase-shifting winding or each extended delta coil theoretically contains the basic coil D1 and the extended coil Y1. The number of turns of the basic coil D1 and the number of turns of the extended coil Y1 contained in the winding coils of different phases among the 16 low-voltage phase-shifting windings are specifically configured according to the data in the following table. It should be noted that the basic coil D1 constitutes the basic triangular side of the zigzag delta, and the extended coil Y1 constitutes the extended side of the zigzag delta. When the number of turns of the extended coil Y1 is zero, such as the No. 1 coil at a phase angle of 60° listed in the table, the three basic coils D1 are connected in Δ shape as shown in a specific example such as Figure 1 Figure (a) therein. When the number of turns of the basic coil D1 is zero, such as the No. 9 coil at a phase angle of 30° listed in the table, the three extended coils Y1 are connected in Y shape as shown in a specific example such as Figure 1 Figure (b) therein. And Figure 1 Figure (c) therein shows the schematic layout structure when the low-voltage phase-shifting windings are arranged in the positive phase, Figure 1 Figure (d) therein shows the schematic layout structure when the low-voltage phase-shifting windings are arranged in the reverse phase.

[0021] This embodiment provides a phase distribution table for each of the 16 low-voltage phase-shifting windings, a turn number combination configuration table for the basic coil D1 and the extended coil Y1 in each phase coil corresponding to each phase angle, and also provides two different turn number combination configuration data tables - combination 1 or combination 2. According to the total number of turns of the basic coil D1 + the extended coil Y1 and the input-output voltage level, data such as the number of turns of the input winding on the high-voltage side can be calculated based on common physical knowledge. Also, based on the magnitude of the output power, data such as the wire diameters of the input and output windings can be calculated.

[0022]

[0023]

[0024] Illustrative example, for instance (1), the theoretical phase angle A1 of the low-voltage winding with serial number 1 is +60°. There are two selectable turn number combination configurations. Among them, the number of turns of the basic coil D1 in combination 1 is 12 turns, and the number of turns of the extended coil Y1 is 0 turn, with a total of 12 turns. Thus, the low-voltage winding with serial number 1 is in the △ connection as shown in Figure 1 Figure (a); (2), the theoretical phase angle A1 of the low-voltage winding with serial number 3 is +52.5°. There are also two selectable turn number combination configurations. The number of turns of the basic coil D1 in its combination 2 is 11 turns, and the number of turns of the extended coil Y1 is 2 turns, with a total of 13 turns. Thus, the low-voltage winding with serial number 3 is in the positive-phase extended delta connection as shown in Figure 1 Figure (c); (3), the theoretical phase angle A1 of the low-voltage winding with serial number 11 is +22.5°. There are also two selectable turn number combination configurations. The number of turns of the basic coil D1 in its combination 2 is 4 turns, and the number of turns of the extended coil Y1 is 6 turns, with a total of 10 turns. Thus, the low-voltage winding with serial number 11 is in the reverse-phase extended delta connection as shown in Figure 1 Figure (d).

[0025] It should be noted that the conventional phase sorting rule is between -30° and +30°, but in this invention, the phase angle is defined between 0° and 60°, which is just a different representation method. Therefore, subtracting 30° from the phase data listed in the table will be consistent with the conventional arrangement representation. Additionally, it should be noted that the data in combination 1 or combination 2 cannot be mixed and selected. For example, in the same transformer 100, it is not allowed to use a chaotic usage mode such as using combination 1 for the coil with serial number 1 and combination 2 for the coil with serial number 2. That is, after deciding to adopt the data of any one combination, each serial number coil can only select the data in that combination. For example, after deciding to select combination 1, all coils from serial number 1 to serial number 16 use combination 1.

[0026] As Figure 2As shown in the figure, a power supply and distribution system includes a three-phase phase-shifting transformer 100, a high-voltage power distribution cabinet 101 configured on the input side of the phase-shifting transformer 100, and a DC load power distribution cabinet 102 configured on the output side of the phase-shifting transformer 100. The phase-shifting transformer 100 is also integrated in a separate power distribution cabinet. The high-voltage power distribution cabinet 101, the phase-shifting transformer 100, and the DC load power distribution cabinet 102 are arranged in sequence in a unit room. Among them, the voltage levels of the phase-shifting transformer 100 and the high-voltage power distribution cabinet 101 are 10 kV. The outdoor 10 kV three-phase high-voltage cable is connected to the input terminal of the high-voltage power distribution cabinet 101. At least a high-voltage disconnector is configured in the high-voltage power distribution cabinet 101, and an overload protection switch can even be installed. The output terminal of the high-voltage power distribution cabinet 101 is connected to the wiring terminal of the three-phase high-voltage end winding of the phase-shifting transformer 100 through a high-voltage cable.

[0027] Among them, the low-voltage end winding itself outputs AC electric energy, but indirectly provides electric energy output for terminal DC loads such as servers used in the information center through rectification devices (AC / DC) that convert AC to DC, such as rectification modules 4 and DC busbars 5. The output terminal of each low-voltage end winding is connected to at least one AC / DC rectification module 4. The output voltage of the low-voltage end winding is adapted to the working voltage level of the rectification module 4, and the output voltage of the rectification module 4 is also adapted to the working voltage level of the DC busbar 5. In the specific circuit layout, the output terminal of the low-voltage end winding is connected to the input end of the DC load power distribution cabinet 102 through a wiring terminal and an electrical lead. The rectification modules 4 and DC busbars 5 are arranged in the DC load power distribution cabinet 102. Isolating switches can be provided between the DC busbars in different DC load power distribution cabinets 102. The input end of the rectification module 4 is connected to the input end of the DC load power distribution cabinet 102 through a control switch, and an overload protection switch can even be installed. The output end of the rectification module 4 is electrically connected to the DC busbar 5 through a control switch.

[0028] In the actual application design, for different output powers, it can be adjusted by changing the wire diameter of the coils on the high- and low-voltage sides, the number of sub-windings of the output winding on the low-voltage end, etc.; for different input voltage levels, by changing the number of turns of the input high-voltage end winding, the low-voltage end winding can output low-voltage AC voltages of different levels, so that the output voltage levels of the rectification module 4 or the DC busbar 5 can be one of DC336V, 240V, 110V, 64V, 48V, or even 12V, which is used to provide DC power for DC loads such as servers used in the information center. The output end of the DC busbar 5 can also be connected to different individual load devices, such as a server host, through discrete switches.

[0029] Among them, the number of low-voltage side windings arranged on each iron core column can be designed and determined as 16×n (n = 1, 2, 3, or 4) according to factors such as the size of the load itself and the capacity of the rectification module 4. Further, an energy storage device (not shown in the figure) is arranged on the side of the DC load power distribution cabinet 102. The energy storage device is a battery pack, and the battery pack is connected to the DC busbar 5 through an energy storage controller. The energy storage controller is signal-connected to the central controller and is used for two-way operation, capable of both charging the battery pack and releasing electrical energy to the DC busbar 5.

[0030] Further, temperature probes of, for example, model PT100 (not shown in the figure) are respectively arranged in the high-voltage side winding and the low-voltage side winding. A dedicated central control cabinet 103 is also arranged on the side of the DC load power distribution cabinet 102. A central controller is arranged in the central control cabinet 103, and the temperature probe is signal-connected to the central controller. Secondly, the control switches in the high-voltage power distribution cabinet 101 and the DC load power distribution cabinet 102 are all signal-connected to the central controller. In this way, the central controller can not only control the control switches in the high-voltage power distribution cabinet 101 and the DC load power distribution cabinet 102 in an associated manner, but also respond to the transformer temperature signal provided by the temperature probe to implement alarm or control the high-voltage switch on the primary side or the low-voltage switch on the low-voltage side. Secondly, a remote communication unit can also be arranged in the central control cabinet 103, and the central controller can interact various signals such as voltage, current, power consumption, and temperature with a remote control or monitoring center through the remote communication unit.

[0031] The transformer 100 and the applied power supply and distribution system according to the embodiments of the present disclosure can not only directly convert high voltage into low voltage, thereby simplifying the structure of the high-voltage power supply circuit, but also have a relatively good harmonic elimination effect due to the relatively optimized electrical structure of the low-voltage side winding.

Claims

1. A Δ-Δ phase-shifting transformer with a 16-fold winding output, where the high-voltage side winding is connected in Δ configuration, and the low-voltage side winding includes at least one sub-winding. Each of the sub-windings consists of 16 three-phase low-voltage phase-shifting windings connected in extended Δ configuration; each phase coil of the low-voltage phase-shifting winding is composed of a basic coil D1 and an extended coil Y1. The basic coil D1 is used to construct the triangular side of the phase-shifting winding, and the extended coil Y1 is used to construct the triangular extended side of the phase-shifting winding. It is characterized in that the theoretical phase angle distribution of each low-voltage phase-shifting winding of each sub-winding and the turn combination configuration of the basic coil D1 and the extended coil Y1 in each phase coil of different phase windings are arranged according to the data of any one of the combinations 1 or 2 listed in the following table; wherein, when the number of turns of the extended coil Y1 is zero, the low-voltage phase-shifting winding is entirely composed of the basic coil D1 to form a winding connected in Δ configuration. When the number of turns of the basic coil D1 is zero, the low-voltage phase-shifting winding is entirely composed of the extended coil Y1 to form a winding connected in Y configuration; when the phase angle A1 is greater than 30°, it indicates that the low-voltage phase-shifting winding is arranged in positive phase, and when the phase angle A1 is less than 30°, it indicates that the low-voltage phase-shifting winding is arranged in reverse phase.

2. The phase-shifting transformer according to claim 1, It is characterized in that the coils of each phase of one sub-winding are tightly bound together, and the coils of different sub-windings are arranged side by side vertically.

3. The phase-shifting transformer according to claim 1, It is characterized in that temperature probes are respectively arranged in the high-voltage side winding and the low-voltage side winding to detect and output the temperature signals of the coils.

4. A power supply and distribution system, including the phase-shifting transformer according to claim 1, 2 or 3, a high-voltage power distribution cabinet configured on the input side of the phase-shifting transformer, and a DC load power distribution cabinet configured on the output side of the phase-shifting transformer. The outgoing line end of the high-voltage power distribution cabinet is electrically connected to the three-phase high-voltage winding of the phase-shifting transformer, and the low-voltage phase-shifting winding of the phase-shifting transformer is electrically connected to the incoming line end of the DC load power distribution cabinet.

5. The power supply and distribution system according to claim 4, It is characterized in that an AC / DC rectification module and a DC busbar are arranged in the DC load power distribution cabinet. The rectification module is used to rectify the AC signal provided by the low-voltage phase-shifting winding into a DC signal and output it to the DC busbar, and the DC busbar is used to provide DC power to the DC load.

6. The power supply and distribution system according to claim 5, It is characterized in that each output end of the low-voltage phase-shifting winding is connected to at least one AC / DC rectification module.

7. The power supply and distribution system according to claim 5, It is characterized in that it further includes an energy storage device, and the energy storage device is connected to the DC busbar through an energy storage controller.

8. The power supply and distribution system according to claim 4, It is characterized in that it further includes a central control cabinet configured on the side of the DC load power distribution cabinet. A central controller is arranged in the central control cabinet, and the central controller is signal-connected to the control switches arranged in the high-voltage power distribution cabinet and the DC load power distribution cabinet.

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