Wind power integration system and method
By setting up step-down units and connecting busbars between wind farms and thermal power plants, the problem of voltage inconsistency was solved, and safe and reliable wind power access was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-19
- Publication Date
- 2026-03-13
AI Technical Summary
The 35kV voltage output from existing wind farms is inconsistent with the 10kV power distribution system of thermal power plants, making it difficult for wind power to be connected to thermal power plants.
The first and second step-down units are connected to the output lines of the wind power plant respectively, and are interconnected through one to four sections of connecting busbars to reduce the voltage from 35kV to 10kV, thus meeting the power demand of the thermal power plant.
This effectively reduced the voltage of wind power, meeting the voltage matching requirements of thermal power plants and ensuring power safety and reliability.
Smart Images
Figure CN121663622A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of wind power generation technology, and in particular to a wind power grid connection system and method. Background Technology
[0002] The electricity generated by wind turbines in existing wind farms is stepped up to 35kV via box-type transformers and then transmitted through 35kV collection lines. However, most of the current thermal power plant flexibility retrofit projects involve 300MW-class thermal power units, whose corresponding plant power distribution systems are primarily 10kV. The 35kV transmission voltage from wind power plants differs from the 10kV connection voltage, and the plant power distribution system voltage for thermal power units is also relatively low. Summary of the Invention
[0003] The technical problem to be solved by the present invention is to provide a wind power grid connection system and method that can reduce the output voltage of wind farms before connecting them to thermal power plants, thereby meeting the requirements for wind power systems to connect to thermal power plants.
[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A wind power grid connection system includes: a first step-down unit, a second step-down unit, a first-section connecting busbar, a second-section connecting busbar, a third-section connecting busbar, and a fourth-section connecting busbar, wherein... The first end of the first step-down unit is connected to the first output line of the wind farm, and the second end of the first step-down unit outputs two first transmission lines; the two first transmission lines are connected to the section of the busbar. The first end of the second step-down unit is connected to the second output line of the wind farm, and the second end of the second step-down unit outputs two second transmission lines; the two second transmission lines are connected to the two-section busbar. According to the nature and capacity of the energized load connected to the busbar, the first-section busbar, the second-section busbar, the third-section busbar, and the fourth-section busbar are interconnected.
[0005] Optionally, the first step-down unit includes: First busbar; First split transformer; The first busbar is connected to the first output line of the wind power plant and the first split transformer; the first split transformer outputs two first transmission lines.
[0006] Optionally, the second buck unit includes: Second busbar; Second split transformer; The second busbar is connected to the second output line and the second split transformer of the wind power plant; the second split transformer outputs two second transmission lines.
[0007] Optionally, the first-section, second-section, third-section, and fourth-section connecting busbars each include two sub-level connecting busbars, wherein, The section of the connecting busbar includes: a first connecting busbar and a second connecting busbar; The two-section connecting busbar includes: two sections of first connecting busbar and two sections of second connecting busbar; The three-section connecting busbar includes: three sections of first connecting busbar and three sections of second connecting busbar; The four-section connecting busbar includes: four sections of first connecting busbar and four sections of second connecting busbar.
[0008] Optionally, the first connecting busbar is connected to one first transmission line output from the first split transformer, and the second connecting busbar is connected to one first transmission line output from the first split transformer. The two sections of the first connecting busbar are connected to one second transmission line output from the second split transformer, and the two sections of the second connecting busbar are connected to one second transmission line output from the second split transformer.
[0009] Optionally, the three sections of the first connecting busbar and the three sections of the second connecting busbar are respectively connected to the two third transmission lines output from the first high-voltage transformer of the thermal power plant. The four sections of the first connecting busbar and the four sections of the second connecting busbar are respectively connected to the two fourth transmission lines output from the second high-voltage transformer of the thermal power plant.
[0010] Optionally, the first section of the first connecting busbar, the second section of the second connecting busbar, the second section of the first connecting busbar, the second section of the second connecting busbar, the third section of the first connecting busbar, the third section of the second connecting busbar, the fourth section of the first connecting busbar, and the fourth section of the second connecting busbar are interconnected by transmission lines; depending on the nature and capacity of the energized load connected to the busbar, one or two transmission lines are led out from each of the first section of the first connecting busbar, the second section of the second connecting busbar, the second section of the first connecting busbar, the second section of the second connecting busbar, the third section of the first connecting busbar, the third section of the second connecting busbar, the fourth section of the first connecting busbar, and the fourth section of the second connecting busbar.
[0011] Optionally, the voltages at the first section of the first connecting busbar, the second section of the second connecting busbar, the second section of the first connecting busbar, the second section of the second connecting busbar, the third section of the first connecting busbar, the third section of the second connecting busbar, the fourth section of the first connecting busbar, and the fourth section of the second connecting busbar are equal and less than the voltages at the first busbar and the second busbar. The present invention also provides a wind power grid connection method, applied to the wind power grid connection system described above, the method comprising: Obtain the first and second output lines of the wind farm; Connect the first output line to the first terminal of the first step-down unit, and connect the second output line to the first terminal of the second step-down unit; Connect the two first transmission lines output from the second end of the first step-down unit to a section of connecting busbar; Connect the two second transmission lines output from the second end of the second step-down unit to the two sections of the busbar. Based on the nature and capacity of the energized load connected to the busbar, the first, second, third, and fourth sections of the busbar are interconnected.
[0012] Optionally, depending on the nature and capacity of the energized load connected to the busbar, the first, second, third, and fourth sections of the energized busbar are interconnected, including: When the energized load capacity of any one of the four sub-level energized busbars (first-level, second-level, third-level, and fourth-level) exceeds a preset value, or when the nature of the energized load is of an important type, the number of outgoing lines of the sub-level energized busbar with the energized load capacity exceeding the preset value or the nature of the energized load being of an important type is determined to be 2.
[0013] The above-described solution of the present invention has at least the following beneficial effects: The above-described solution of the present invention includes: a first step-down unit, a second step-down unit, a first-section connecting busbar, a second-section connecting busbar, a third-section connecting busbar, and a fourth-section connecting busbar. The first end of the first step-down unit is connected to the first output line of the wind farm, and the second end of the first step-down unit outputs two first transmission lines; the two first transmission lines are connected to the first-section connecting busbar. The first end of the second step-down unit is connected to the second output line of the wind farm, and the second end of the second step-down unit outputs two second transmission lines; the two second transmission lines are connected to the second-section connecting busbar. The first-section connecting busbar, the second-section connecting busbar, the third-section connecting busbar, and the fourth-section connecting busbar are interconnected according to the nature and capacity of the load connected to the busbar. This allows for the reduction of the wind farm's output voltage, meeting the requirements for wind power systems to connect to thermal power plants. Attached Figure Description
[0014] Figure 1 This is a structural diagram of a wind power grid connection system according to an embodiment of the present invention; Figure 2 This is a flowchart of a wind power grid connection method according to an embodiment of the present invention; Explanation of reference numerals in the attached figures: 1. First step-down unit; 2. Second step-down unit; 11. First busbar; 12. First split transformer; 21. Second busbar; 22. Second split transformer; 31. First section first connecting busbar; 32. First section second connecting busbar; 41. Second section first connecting busbar; 42. Second section second connecting busbar; 51. Third section first connecting busbar; 52. Third section second connecting busbar; 61. Fourth section first connecting busbar; 62. Fourth section second connecting busbar; 71. First high-voltage transformer; 72. Second high-voltage transformer. Detailed Implementation Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0015] like Figure 1 As shown, an embodiment of the present invention proposes a wind power grid connection system, comprising: a first step-down unit 1, a second step-down unit 2, a first-section connecting busbar, a second-section connecting busbar, a third-section connecting busbar, and a fourth-section connecting busbar, wherein... The first terminal of the first step-down unit 1 is connected to the first output line of the wind farm, and the second terminal of the first step-down unit 1 outputs two first transmission lines. These two first transmission lines are connected to the first section of the connecting busbar. The first output line is one of two series output by the wind farm, and it collects 25MW of wind power capacity at a voltage of 35kV. After the first step-down unit reduces the 35kV voltage of the first output line, it obtains two 10kV first transmission lines, which are then respectively transmitted to two connecting buses in the first section of the connecting busbar.
[0016] The first end of the second step-down unit 2 is connected to the second output line of the wind farm, and the second end of the second step-down unit 2 outputs two second transmission lines. These two second transmission lines are connected to the two connecting busbars. The second output line is the other of two series output by the wind farm, and it collects 25MW of wind power capacity at a voltage of 35kV. After the second step-down unit reduces the 35kV voltage of the second output line, two 10kV second transmission lines are obtained. These two 10kV second transmission lines are then respectively transmitted to two connecting busbars in the two connecting busbars.
[0017] According to the nature and capacity of the energized load connected to the busbar, the first-section busbar, the second-section busbar, the third-section busbar, and the fourth-section busbar are interconnected.
[0018] In this embodiment, the first, second, third, and fourth connecting busbars are four busbars on the thermal power plant side. Each connecting busbar includes two sub-connecting busbars, and each sub-connecting busbar connects to the thermal power plant's electrical load. Based on the nature and capacity of the electrical loads connected to the sub-connecting busbars, dual-circuit power supply is set up for the connecting busbars corresponding to some electrical loads with high reliability and safety; that is, two circuits are set up between the sub-connecting busbars. For example, ... Figure 1 As shown, one section of the first connecting busbar 31 is connected to three sections of the first connecting busbar 51 and three sections of the second connecting busbar 52 respectively, forming two circuits to ensure electrical safety.
[0019] In an optional embodiment of the present invention, the first step-down unit 1 includes: First busbar 11; First split transformer 12; The first busbar 11 is connected to the first output line of the wind power plant and the first split transformer 12 respectively; the first split transformer 12 outputs two circuits to the first transmission line.
[0020] In this embodiment, the first busbar 11 collects the power generated by the wind turbine and transmits it to the first split transformer 12. The first split transformer 12 then outputs two 10kV first transmission lines after split transformation. The main transformer capacity of the first split transformer 12 is (30 / 12.5-12.5) MVA, where 30 represents the split transformer capacity and 15 represents the 10kV side capacity of the split transformer. The voltage level is 35±8x1.25% / 10.5kV-10.5kV, where 35 represents the rated voltage on the high-voltage side of the transformer, ±8x1.25% represents the tap changer range of the on-load tap changer, 8 represents the 8 tap positions of the transformer tap changer, 1.25% represents the tap changer range per position, and 10.5 represents the rated voltage on the low-voltage side of the transformer.
[0021] In an optional embodiment of the present invention, the second step-down unit 2 includes: Second busbar 21; Second split transformer 22; The second busbar 21 is connected to the second output line of the wind power plant and the second split transformer 22; the second split transformer 22 outputs two circuits to the second transmission line.
[0022] In this embodiment, the second busbar 21 collects the power generated by the wind turbine and transmits it to the second split transformer 22. The second split transformer 22 then outputs two 10kV second transmission lines after split transformation. The main transformer capacity of the second split transformer 22 is (30 / 12.5-12.5) MVA, where 30 represents the split transformer capacity and 15 represents the 10kV side capacity of the split transformer. The voltage level is 35±8x1.25% / 10.5kV-10.5kV, where 35 represents the rated voltage on the high-voltage side of the transformer, ±8x1.25% represents the tap changer range of the on-load tap changer, 8 represents the 8 tap positions of the transformer tap changer, 1.25% represents the tap changer range per position, and 10.5 represents the rated voltage on the low-voltage side of the transformer.
[0023] The 50MW of electricity generated by the wind farm is divided into two series, with each series containing 25MW of wind power capacity. The two series are transmitted to the first step-down unit and the second step-down unit respectively through the first transmission line and the second transmission line.
[0024] In an optional embodiment of the present invention, the first-section connecting busbar, the second-section connecting busbar, the third-section connecting busbar, and the fourth-section connecting busbar each include two sub-level connecting busbars, wherein, The section of the connecting busbar includes: a first connecting busbar 31 and a second connecting busbar 32; The two-section connecting busbar includes: two sections of first connecting busbar 41 and two sections of second connecting busbar 42; The three-section connecting busbar includes: three sections of first connecting busbar 51 and three sections of second connecting busbar 52; The four connecting busbars include: four first connecting busbars 61 and four second connecting busbars 62.
[0025] In this embodiment, as Figure 1 As shown, each busbar segment is divided into two sub-busbars. The electrical loads connected to the two sub-busbars in the same busbar segment are of the same nature, for example, they are both connected to the main plant charge.
[0026] In an optional embodiment of the present invention, the first connecting bus 31 is connected to one first transmission line output by the first split transformer 12, and the second connecting bus 32 is connected to one first transmission line output by the first split transformer 12. The two sections of the first connecting busbar 41 are connected to one second transmission line output by the second split transformer 22, and the two sections of the second connecting busbar 42 are connected to one second transmission line output by the second split transformer 22.
[0027] In this embodiment, the two sub-stage connecting busbars in the first connecting busbar section are respectively connected to the two 10kV first transmission lines output by the first split transformer 12. The two sub-stage connecting busbars in the second connecting busbar section are respectively connected to the two 10kV second transmission lines output by the second split transformer 22.
[0028] In an optional embodiment of the present invention, the three sections of the first connecting busbar 51 and the three sections of the second connecting busbar 52 are respectively connected to the two third transmission lines output from the first high-voltage transformer 71 of the thermal power plant. The four sections of the first connecting busbar 61 and the four sections of the second connecting busbar 62 are respectively connected to the two fourth transmission lines output from the second high-voltage transformer 72 of the thermal power plant.
[0029] In this embodiment, the input terminals of the first high-voltage transformer 71 and the second high-voltage transformer 72 are respectively connected to the thermal power generating units of the thermal power plant, and the power generated by the thermal power plant is stepped down and output to the connecting bus section through two transmission lines. The thermal power generating units and the wind power generating units of the wind power plant jointly supply power to the four connecting bus sections.
[0030] In an optional embodiment of the present invention, the first connecting busbar 31, the second connecting busbar 32, the second connecting busbar 41, the second connecting busbar 42, the third connecting busbar 51, the third connecting busbar 52, the fourth connecting busbar 61, and the fourth connecting busbar 62 are interconnected by transmission lines; depending on the nature and capacity of the load connected to the busbar, one or two transmission lines are respectively led out from the first connecting busbar 31, the second connecting busbar 32, the second connecting busbar 41, the second connecting busbar 42, the third connecting busbar 51, the third connecting busbar 52, the fourth connecting busbar 61, and the fourth connecting busbar 62.
[0031] In this embodiment, as Figure 1 As shown, the electrical loads connected to the sub-level busbars may be for main plant, desulfurization, coal conveying, etc., and the capacity of the electrical load connected to each sub-level busbar is different. When the electrical load connected to the sub-level busbar is a load with high importance, reliability, and safety requirements, and has a large capacity, the sub-level busbar needs to be supplied with dual circuits. For example, as... Figure 1 As shown, two transmission lines are respectively led out from the first connecting busbar 31, the second connecting busbar 32, the second first connecting busbar 41, the second second connecting busbar 42, the third first connecting busbar 51, and the fourth first connecting busbar 61. One of them serves as a backup line to ensure power supply safety. It should be noted that when two transmission lines are required, the connection of each sub-level connecting busbar can be selected appropriately based on the connection status of other sub-level connecting busbars, according to the specific circumstances.
[0032] In an optional embodiment of the present invention, the voltages at the first connecting bus 31, the second connecting bus 32, the second connecting bus 41, the second connecting bus 42, the third connecting bus 51, the third connecting bus 52, the fourth connecting bus 61, and the fourth connecting bus 62 are equal and less than the voltages at the first bus 11 and the second bus 21. In this embodiment, the voltage at the following sections is 10kV: the first connecting busbar 31, the second connecting busbar 32, the second connecting busbar 41, the second connecting busbar 42, the third connecting busbar 51, the third connecting busbar 52, the fourth connecting busbar 61, and the fourth connecting busbar 62. This meets the requirements of the power distribution system for thermal power plants. The voltage at the first busbar 11 and the second busbar 21 is 35kV.
[0033] The wind power access system of the present invention can meet the requirements of a wind power access system for full self-generation and self-consumption in thermal power flexibility retrofit projects. The wind power is collected through a 35kV collection line and then connected to a voltage step-down unit. After being stepped down by the voltage step-down unit, the wind power is transmitted to the connection bus of the thermal power plant.
[0034] like Figure 2 As shown, embodiments of the present invention also provide a wind power grid connection method, applied to the wind power grid connection system described above, the method comprising: Step 11: Obtain the first and second output lines of the wind farm; Step 12: Connect the first output line to the first terminal of the first step-down unit, and connect the second output line to the first terminal of the second step-down unit; Step 13: Connect the two first transmission lines output from the second end of the first step-down unit to a section of connecting busbar; Step 14: Connect the two second transmission lines output from the second terminal of the second step-down unit to the two sections of the busbar. Step 15: Based on the nature and capacity of the energized load connected to the busbar, connect the first, second, third, and fourth sections of the energized busbar to each other.
[0035] In step 15, the interconnection of the first, second, third, and fourth sections of the busbar connected to the energized load, based on the nature and capacity of the load, may include: Step 151: When the energized load capacity of any one of the four sub-level energized busbars (first-level, second-level, third-level, and fourth-level) is greater than a preset value, or the nature of the energized load is of an important type, the number of lead-out lines of the sub-level energized busbar with the energized load capacity greater than the preset value or the nature of the energized load being of an important type is determined to be 2.
[0036] It should be noted that this method is the same as the method described in the above system. All implementation methods in the above system embodiments are applicable to the embodiments of this method and can achieve the same technical effect.
[0037] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A wind power grid connection system, characterized in that, include: The system comprises a first step-down unit (1), a second step-down unit (2), a first-section connecting busbar, a second-section connecting busbar, a third-section connecting busbar, and a fourth-section connecting busbar, wherein... The first end of the first step-down unit (1) is connected to the first output line of the wind power plant, and the second end of the first step-down unit (1) outputs two first transmission lines; the two first transmission lines are connected to the section of the busbar. The first end of the second step-down unit (2) is connected to the second output line of the wind power plant, and the second end of the second step-down unit (2) outputs two second transmission lines; the two second transmission lines are connected to the two-section busbar. According to the nature and capacity of the energized load connected to the busbar, the first-section busbar, the second-section busbar, the third-section busbar, and the fourth-section busbar are interconnected.
2. The wind power grid connection system according to claim 1, characterized in that, The first step-down unit (1) includes: First busbar (11); First split transformer (12); The first busbar (11) is connected to the first output line of the wind power plant and the first split transformer (12); the first split transformer (12) outputs two first transmission lines.
3. The wind power grid connection system according to claim 2, characterized in that, The second step-down unit (2) includes: Second busbar (21); Second split transformer (22); The second busbar (21) is connected to the second output line of the wind power plant and the second split transformer (22); the second split transformer (22) outputs two second transmission lines.
4. The wind power grid connection system according to claim 3, characterized in that, The first-section, second-section, third-section, and fourth-section connecting busbars each include two sub-level connecting busbars, wherein... The section of the connecting busbar includes: a first connecting busbar (31) and a second connecting busbar (32); The two-section connecting busbar includes: two sections of first connecting busbar (41) and two sections of second connecting busbar (42). The three-section connecting busbar includes: three sections of first connecting busbar (51) and three sections of second connecting busbar (52); The four connecting busbars include: four first connecting busbars (61) and four second connecting busbars (62).
5. The wind power grid connection system according to claim 4, characterized in that, The first section of the first connecting busbar (31) is connected to one first transmission line output by the first split transformer (12), and the second section of the connecting busbar (32) is connected to one first transmission line output by the first split transformer (12). The two sections of the first connecting busbar (41) are connected to the second transmission line output by the second split transformer (22), and the two sections of the second connecting busbar (42) are connected to the second transmission line output by the second split transformer (22).
6. The wind power grid connection system according to claim 4, characterized in that, The three sections of the first connecting busbar (51) and the three sections of the second connecting busbar (52) are respectively connected to the two third transmission lines output by the first high-voltage transformer (71) of the thermal power plant; The four sections of the first connecting busbar (61) and the four sections of the second connecting busbar (62) are respectively connected to the two fourth transmission lines output from the second high-voltage transformer (72) of the thermal power plant.
7. The wind power grid connection system according to claim 4, characterized in that, The first busbar (31), the second busbar (32), the first busbar (41), the second busbar (42), the first busbar (51), the second busbar (52), the first busbar (61), and the second busbar (62) are interconnected by transmission lines. Depending on the nature and capacity of the load connected to the busbar, one or two transmission lines are led out from the first busbar (31), the second busbar (32), the first busbar (41), the second busbar (42), the first busbar (51), the second busbar (52), the first busbar (61), and the second busbar (62).
8. The wind power grid connection system according to claim 4, characterized in that, The voltages at the first connecting bus (31), the second connecting bus (32), the second first connecting bus (41), the second second connecting bus (42), the third first connecting bus (51), the third second connecting bus (52), the fourth first connecting bus (61), and the fourth second connecting bus (62) are equal and less than the voltages at the first bus (11) and the second bus (21).
9. A wind power grid connection method, characterized in that, The method, applied to the wind power grid connection system according to any one of claims 1 to 8, comprises: Obtain the first and second output lines of the wind farm; Connect the first output line to the first end of the first step-down unit 1, and connect the second output line to the first end of the second step-down unit 2; Connect the two first transmission lines output from the second end of the first step-down unit 1 to a section of connecting busbar; Connect the two second transmission lines output from the second end of the second step-down unit 2 to the two sections of the busbar. Based on the nature and capacity of the energized load connected to the busbar, the first, second, third, and fourth sections of the busbar are interconnected.
10. The wind power grid connection method according to claim 9, characterized in that, Based on the nature and capacity of the energized load connected to the busbar, the first, second, third, and fourth sections of the energized busbar are interconnected, including: When the energized load capacity of any one of the four sub-level energized busbars (first-level, second-level, third-level, and fourth-level) exceeds a preset value, or when the nature of the energized load is of an important type, the number of outgoing lines of the sub-level energized busbar with the energized load capacity exceeding the preset value or the nature of the energized load being of an important type is determined to be 2.