Converting and boosting cabin and power supply system thereof

Abstract

The utility model relates to a converter boost cabin and a power supply system thereof, belonging to the technical field of power supply and distribution. Comprising a three-winding transformer, and three windings of the transformer comprise a high-voltage coil, a low-voltage coil and a third winding; the low-voltage coil is used for being connected with the output end of a PCS converter of the current transformation and voltage boosting cabin, the high-voltage coil is used for being connected with the high-voltage output end of the current transformation and voltage boosting cabin, and the third winding is used for reducing voltage to supply power to secondary equipment of the current transformation and voltage boosting cabin. Therefore, an auxiliary transformer is saved, the wiring structure is simplified, the space of the box body is saved, and the cost of a complete set of products is greatly reduced.

Description

Technical Field

[0001] This utility model relates to a converter booster chamber and its power supply system, belonging to the field of power supply and distribution technology. Background Technology

[0002] In recent years, the new energy industry has developed rapidly, and the demand for electrical equipment in wind, solar, and energy storage fields has surged. The electricity generated by wind, solar, and energy storage is all low-voltage DC power. To connect to the grid, it needs to pass through a converter to convert DC power into AC power, and then through a transformer to increase the voltage before being connected to the grid. However, the voltage inverted by the converter is mostly 0.63kV, 0.69kV, 0.8kV, etc. In addition to primary equipment such as converters, transformers, and switchgear, the complete set of equipment responsible for converter voltage step-up also includes many secondary equipment for monitoring, communication, etc. The operating voltage of these devices is the standard 220V phase voltage. This requires the addition of an auxiliary power supply transformer to convert the 0.63kV, 0.69kV, and 0.8kV voltages inverted by the converter into the standard 0.4kV voltage for use by the secondary equipment in the enclosure.

[0003] Existing power supply systems for converter booster chambers, such as Figure 1 As shown, taking a 2500kVA capacity as an example, the DC power is inverted to AC 0.69kV by the PCS converter, stepped up to 35kV by the 2500kVA main transformer, and connected to the 35kV bus. On the other side, the AC 0.69kV is stepped down to 0.4kV by an 80kVA auxiliary transformer to supply the 0.4kV distribution line. The existing internal power supply system of the enclosure is as follows: Figure 2 As shown, the electricity generated by wind, solar, and energy storage is inverted to AC 0.69kV by PCS converter 4, then stepped up to 35kV by 2500kVA main transformer 3, and connected to the 35kV busbar via high-voltage switchgear 5. In order to ensure the normal operation of the 0.4kV secondary equipment in the enclosure, a bypass needs to be added on the 0.69kV side. Through 80kVA auxiliary transformer 1, the 0.69kV voltage is stepped down to 0.4kV, and then supplied to the 0.4kV distribution line.

[0004] For example, Chinese patent application CN221467395U proposes an integrated user-side energy storage device. The design includes an auxiliary transformer cabinet containing an auxiliary transformer. One end of the auxiliary transformer is connected to the AC side of a bidirectional converter, and the other end is connected to auxiliary equipment (i.e., secondary equipment) to provide power to the auxiliary equipment. The auxiliary equipment includes fire-fighting gas cylinders, air-cooled air conditioners, and cabinet air conditioners.

[0005] The power supply system has the following problems during use:

[0006] ① The addition of auxiliary transformer 1 occupies the already limited internal space of the enclosure 6. At the same time, the heat generated by auxiliary transformer 1 during operation and the heat dissipation problem must also be considered.

[0007] ② The incoming and outgoing line protection switches of the auxiliary transformer 1 are all installed in the communication power cabinet 2. The incoming line of the auxiliary transformer 1 needs to be introduced from the secondary side of the main transformer 3. The wiring is relatively complicated, which increases the cost of cables and occupies the space inside the communication power cabinet 2 and the enclosure 6.

[0008] ③ The addition of auxiliary transformer 1 increased the cost of the entire power supply system;

[0009] ④ The addition of auxiliary transformer 1 increases the space area of ​​enclosure 6, further increasing the cost of the complete set. Utility Model Content

[0010] The purpose of this utility model is to provide a power supply system for a converter booster chamber to solve the problems of high requirements for internal space and high cost of the converter booster chamber; it also provides a converter booster chamber to solve the problems of large size, complex internal wiring and high cost of the converter booster chamber.

[0011] To achieve the above objectives, the solution of this utility model includes:

[0012] The power supply system for the converter booster compartment of this utility model includes a three-winding transformer. The three windings of the transformer include a high-voltage coil, a low-voltage coil, and a third winding. The low-voltage coil is used to connect to the PCS converter of the converter booster compartment, the high-voltage coil is used to connect to the high-voltage end of the converter booster compartment, and the third winding is used to step down the voltage to supply power to the secondary equipment of the converter booster compartment.

[0013] Furthermore, the low-voltage coil is directly mounted on the transformer core, and the high-voltage coil is mounted outside the low-voltage coil.

[0014] Furthermore, a third winding is added to the bottom of the high-voltage coil.

[0015] Furthermore, the high-voltage coil adopts a three-phase delta connection; the low-voltage coil adopts a three-phase Y connection; and the third winding adopts a three-phase Y connection.

[0016] The beneficial effects of this utility model are as follows: By adding a third winding to the main transformer in the existing technology, this utility model can directly convert the voltage required by the secondary equipment, save the auxiliary transformer, reduce the space requirements of the converter booster chamber, and greatly reduce the cost of the complete set of products.

[0017] This utility model also provides a converter booster compartment, including a PCS converter, secondary equipment of the converter booster compartment, and a three-winding transformer; the three-winding transformer includes a high-voltage coil, a low-voltage coil, and a third winding; the low-voltage coil is used to connect to the PCS converter of the converter booster compartment, the high-voltage coil is used to connect to the high-voltage end of the converter booster compartment, and the third winding is used to step down the voltage to supply power to the secondary equipment of the converter booster compartment.

[0018] Furthermore, the low-voltage coil is directly mounted on the transformer core, and the high-voltage coil is mounted outside the low-voltage coil.

[0019] Furthermore, a third winding is added to the bottom of the high-voltage coil.

[0020] Furthermore, the high-voltage coil adopts a three-phase delta connection; the low-voltage coil adopts a three-phase Y connection; and the third winding adopts a three-phase Y connection.

[0021] The beneficial effects of this utility model are as follows: By adding a third winding to the main transformer in the existing technology, this utility model can directly convert the voltage required by the secondary equipment, save the auxiliary transformer, simplify the internal wiring structure of the converter booster compartment, save the space of the converter booster compartment, and greatly reduce the cost of the complete set of products. Attached Figure Description

[0022] Figure 1 This is the main wiring diagram of the converter booster chamber in the existing background technology;

[0023] Figure 2 This is a layout diagram of a converter booster chamber in existing background technology;

[0024] Figure 3 This is the main wiring diagram of the converter booster chamber of this utility model;

[0025] Figure 4 This is a cross-sectional view of the transformer winding of the converter booster compartment of this utility model.

[0026] The diagram includes: 1: Auxiliary transformer; 2: Communication power cabinet; 3: Main transformer; 4: Converter; 5: High voltage cabinet; 6: Enclosure. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be described in a clear and complete manner below with reference to the accompanying drawings and embodiments.

[0028] The concept of this utility model lies in optimizing the existing power supply system. The converter booster compartment and its power supply system utilize only one transformer, with a third winding added to the bottom of the transformer's high-voltage coil to replace the auxiliary transformer, thus providing power to the secondary equipment. This simplifies the wiring structure, reduces costs, and achieves cost reduction and efficiency improvement, further seizing the opportunities presented by the new energy trend.

[0029] Example of a power supply system for a converter booster chamber:

[0030] The power supply system for the converter booster compartment includes a three-winding transformer. The transformer has three windings: a high-voltage coil, a low-voltage coil, and a third winding. The low-voltage coil is used to connect to the PCS converter in the converter booster compartment. The high-voltage coil is used to connect to the high-voltage end of the converter booster compartment. The third winding is used to step down the voltage to supply power to the secondary equipment in the converter booster compartment.

[0031] The low-voltage coil is directly mounted on the transformer core, while the high-voltage coil is mounted outside the low-voltage coil. The third winding replaces the function of the auxiliary transformer in the prior art and can be mounted at any position on the core of the three-winding transformer to achieve the function of stepping down the voltage to 0.4kV. In this embodiment, the third winding is mounted outside the low-voltage coil and is located at the bottom of the high-voltage coil for convenient wiring of the three-winding transformer.

[0032] The high-voltage coil, as one of the high-voltage sides of the three-winding transformer, adopts a three-phase delta (Δ) connection and is connected to the 35kV busbar. The low-voltage coil, as one of the low-voltage sides of the three-winding transformer, adopts a three-phase star (Y) connection and is connected to the output terminal of the PCS converter. The third winding, as one of the low-voltage sides of the three-winding transformer, adopts a three-phase Y connection and is connected to the secondary equipment in the transformer booster compartment. The DC power supply is inverted to AC power by the PCS converter, stepped up and connected to the grid by the three-winding transformer, and then stepped down to supply the secondary equipment.

[0033] Taking a 2500kVA capacity as an example, such as Figure 3 As shown, the DC power is inverted to AC 0.69kV by the PCS converter, stepped up to 35kV by the high-voltage coil of the 2500kVA transformer, and connected to the 35kV bus. On the other side, the AC 0.69kV is stepped down to 0.4kV by the third winding of the 2500kVA transformer to supply the 0.4kV distribution line. The third winding has a capacity of 80kVA.

[0034] like Figure 4 As shown, the transformer windings of the converter booster compartment of this utility model include an iron core, a low-voltage coil, a high-voltage coil, and a third winding. Figure 2 The main transformer 3 is modified by adding a third winding at the bottom of the high-voltage coil to replace the original auxiliary transformer 1, which simplifies the cable connection between the auxiliary transformer 1 and the communication power cabinet 2. Specifically, a third winding with a capacity of 80kVA, the same as the isolation transformer 1, is added to the bottom of the high-voltage coil of the 2500kVA main transformer. This not only eliminates the need for an 80kVA isolation transformer but also omits the cable connection between the 80kVA isolation transformer 1 and the communication power cabinet 2. At the same time, the layout of the enclosure 6 can be further optimized to reduce the size of the enclosure.

[0035] This embodiment omits the auxiliary transformer, eliminating the need to consider the heat generated and dissipation issues during its operation. This simplifies wiring, reduces cable costs, saves internal space, and further lowers the overall power supply system cost. By employing these methods, the original power supply method for the converter booster compartment can be effectively simplified, the cost of the converter booster compartment reduced, and the product's market competitiveness improved.

[0036] Example of a variable-current booster chamber:

[0037] This embodiment provides a technical solution for a converter-boosting chamber, including a PCS converter, secondary equipment of the converter-boosting chamber, and a three-winding transformer. The three-winding transformer includes a high-voltage coil, a low-voltage coil, and a third winding. The low-voltage coil is used to connect to the PCS converter of the converter-boosting chamber, the high-voltage coil is used to connect to the high-voltage end of the converter-boosting chamber, and the third winding is used to step down the voltage to supply power to the secondary equipment of the converter-boosting chamber. DC power is inverted to AC power by the PCS converter, and then stepped up and connected to the grid by the three-winding transformer. Grid power is stepped down by the third winding transformer and then inverted to DC power by the PCS converter. Furthermore, the three-winding transformer can step down the voltage to supply power to the secondary equipment.

[0038] Since the specific implementation process and principle of the converter booster chamber in this embodiment have been described in detail in the embodiment of the converter booster chamber power supply system, they will not be repeated here.

Claims

1. A power supply system for a converter booster chamber, characterized in that, It includes a three-winding transformer, the three windings of which include a high-voltage coil, a low-voltage coil, and a third winding; the low-voltage coil is used to connect to the PCS converter of the converter booster compartment, the high-voltage coil is used to connect to the high-voltage end of the converter booster compartment, and the third winding is used to step down the voltage to supply power to the secondary equipment of the converter booster compartment.

2. The power supply system for the converter booster chamber according to claim 1, characterized in that, The low-voltage coil is directly mounted on the transformer core, and the high-voltage coil is mounted outside the low-voltage coil.

3. The power supply system for the converter booster chamber according to claim 2, characterized in that, A third winding is added to the bottom of the high-voltage coil.

4. The power supply system for the converter booster chamber according to claim 1, characterized in that, The high-voltage coil adopts a three-phase delta connection; the low-voltage coil adopts a three-phase Y connection; and the third winding adopts a three-phase Y connection.

5. A converter pressurization chamber, characterized in that, It includes a PCS converter, secondary equipment of the converter booster compartment, and a three-winding transformer; the three-winding transformer includes a high-voltage coil, a low-voltage coil, and a third winding; the low-voltage coil is used to connect to the PCS converter of the converter booster compartment, the high-voltage coil is used to connect to the high-voltage end of the converter booster compartment, and the third winding is used to step down the voltage to supply power to the secondary equipment of the converter booster compartment.

6. The converter booster chamber according to claim 5, characterized in that, The low-voltage coil is directly mounted on the transformer core, and the high-voltage coil is mounted outside the low-voltage coil.

7. The converter booster chamber according to claim 6, characterized in that, A third winding is added to the bottom of the high-voltage coil.

8. The converter booster chamber according to claim 5, characterized in that, The high-voltage coil adopts a three-phase delta connection; the low-voltage coil adopts a three-phase Y connection; and the third winding adopts a three-phase Y connection.

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