A new 35kV feeder sharing system

Abstract

The application discloses a novel 35kV feeder sharing system, which comprises a 35kV high-voltage switch cabinet, an energy storage system and a box-type station transformer system; the 35kV high-voltage switch cabinet is connected with the energy storage system and the box-type station transformer system, and the system can solve the problem of insufficient 35kV interval reservation of a new energy booster station.

Description

Technical Field

[0001] This invention belongs to the field of new energy wind power and photovoltaic power generation, and relates to a novel 35kV feeder shared system. Background Technology

[0002] With the rapid development of new energy sources in recent years and the increase in forest land, grassland, arable land, basic farmland, ecological red lines, and tourist areas, the land available for new energy power stations is decreasing. Coupled with the extensive development model in the early stages of new energy development and construction, and inadequate preliminary planning, the expansion of substations often results in insufficient 35kV bays, hindering the development of new energy. Furthermore, recent local new energy policies require the inclusion of energy storage in newly built and expanded new energy power stations, further exacerbating the problem of insufficient 35kV bay reserves in new energy substations (switching stations). Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a new type of 35kV feeder sharing system, which can solve the problem of insufficient 35kV bay reservation in new energy booster stations.

[0004] To achieve the above objectives, the novel 35kV feeder shared system of the present invention includes a 35kV high-voltage switchgear, an energy storage system, and a box-type substation transformer system; the 35kV high-voltage switchgear is connected to the energy storage system and the box-type substation transformer system.

[0005] The 35kV high-voltage switchgear includes a 35kV busbar, a handcart-type circuit breaker, an electromagnetic current transformer, a first 35kV high-voltage cable terminal, and a third 35kV high-voltage power cable. The 35kV busbar is divided into two paths after passing through the handcart-type circuit breaker and the electromagnetic current transformer. One path is connected to the energy storage system via the first 35kV high-voltage cable terminal, and the other path is connected to the box-type substation transformer system via the third 35kV high-voltage power cable.

[0006] The 35kV busbar is grounded after passing through a handcart-type circuit breaker and an electromagnetic current transformer, and then through a high-voltage surge arrester.

[0007] The 35kV busbar is grounded after passing through a handcart-type circuit breaker and an electromagnetic current transformer, and then through a grounding switch.

[0008] The 35kV busbar is grounded after passing through a handcart-type circuit breaker and an electromagnetic current transformer, and then through a live indicator.

[0009] The energy storage system includes a second 35kV high-voltage cable terminal, a first 35kV high-voltage cable, a first 35kV load switch, a first 35kV fuse, and an energy storage complete set of equipment; the first 35kV high-voltage cable terminal is connected to the energy storage complete set of equipment via the first 35kV high-voltage cable, the second 35kV high-voltage cable terminal, the first 35kV load switch, and the first 35kV fuse.

[0010] The first 35kV high-voltage cable is equipped with a first zero-sequence current transformer.

[0011] The box-type substation transformer system includes a fourth 35kV high-voltage power cable, a second 35kV high-voltage cable, a second 35kV load switch, a second 35kV fuse, and a 35kV substation transformer.

[0012] The third 35kV high-voltage power cable is connected to the 35kV station service transformer via the second 35kV high-voltage cable, the fourth 35kV high-voltage power cable, the second 35kV load switch, and the second 35kV fuse.

[0013] The second 35kV high-voltage cable is equipped with a second zero-sequence current transformer.

[0014] The present invention has the following beneficial effects:

[0015] In practical operation, the novel 35kV feeder sharing system described in this invention connects the energy storage system and the box-type substation transformer system to the 35kV high-voltage switchgear, reducing the number of 35kV switchgears required for a new energy power plant of the same scale. One 35kV switchgear can connect to 25MW of new energy power generation capacity. It is applicable to the development and construction of new energy projects with limited land use and expansion capabilities. It has the characteristics of simple principle, convenient operation, and strong practicality, and has broad promotion value. It can effectively improve the economic efficiency of existing systems. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention.

[0017] Among them, A is a 35kV high-voltage switchgear, B is an energy storage system, C is a box-type substation transformer system, 1 is a 35kV busbar, 2 is a handcart-type circuit breaker, 3 is an electromagnetic current transformer, 4 is a high-voltage surge arrester, 5 is a grounding switch, 6 is a live indicator, 71 is the first 35kV high-voltage cable terminal, 72 is the second 35kV high-voltage cable terminal, 8 is the first zero-sequence current transformer, 9 is the first 35kV high-voltage cable, 10 is the first 35kV load switch, 11 is the first 35kV fuse, 12 is an energy storage complete set of equipment, 131 is the third 35kV high-voltage power cable, 132 is the fourth 35kV high-voltage power cable, 14 is the second zero-sequence current transformer, 15 is the second 35kV high-voltage cable, 16 is the second 35kV load switch, 17 is the second 35kV fuse, and 18 is a 35kV substation transformer. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, not all embodiments, and are not intended to limit the scope of the present invention. Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion regarding the concepts disclosed in the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0019] The accompanying drawings show structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not drawn to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0020] refer to Figure 1 The novel 35kV feeder shared system of the present invention includes a 35kV high-voltage switchgear A, an energy storage system B, and a box-type substation transformer system C; the 35kV high-voltage switchgear A includes a 35kV busbar 1, a handcart-type circuit breaker 2, an electromagnetic current transformer 3, a high-voltage surge arrester 4, a first 35kV high-voltage cable terminal 71, a third 35kV high-voltage power cable 131, a grounding switch 5, and a live indicator 6; the energy storage system B includes a second 35kV high-voltage cable terminal 72, a first zero-sequence current transformer 8, a first 35kV high-voltage cable 9, a first 35kV load switch 10, a first 35kV fuse 11, and an energy storage complete set of equipment 12; the box-type substation transformer system C includes a fourth 35kV high-voltage power cable 132, a second zero-sequence current transformer 14, a second 35kV high-voltage cable 15, a second 35kV load switch 16, a second 35kV fuse 17, and a 35kV substation transformer 18;

[0021] The 35kV busbar 1 is divided into five paths after passing through the handcart-type circuit breaker 2 and the electromagnetic current transformer 3. The first path is grounded after passing through the high-voltage surge arrester 4, the second path is grounded after passing through the grounding switch 5, the third path is grounded after passing through the live indicator 6, and the fourth path is connected to the energy storage complete set device 12 through the first 35kV high-voltage cable terminal 71, the first 35kV high-voltage cable 9, the second 35kV high-voltage cable terminal 72, the first 35kV load switch 10 and the first 35kV fuse 11. The first 35kV high-voltage cable 9 is equipped with a first zero-sequence current transformer 8.

[0022] The fifth route is connected to the 35kV station service transformer 18 via the third 35kV high-voltage power cable 131, the second 35kV high-voltage power cable 15, the fourth 35kV high-voltage power cable 132, the second 35kV load switch 16 and the second 35kV fuse 17. The second 35kV high-voltage cable 15 is equipped with a second zero-sequence current transformer 14.

[0023] It should be noted that the handcart-type circuit breaker 2 is used for switching the main feeder circuit, and the electromagnetic current transformer 3 is used for protection, measurement and metering of the main feeder circuit.

[0024] This invention replaces the conventional station service transformer with a box-type station service transformer system C. A first 35kV fuse 11, a second 35kV fuse 17, a first 35kV load switch 10, and a second 35kV load switch 16 are added to the high-voltage side of the original station service transformer. The high-voltage side of the box-type station service transformer system C is connected to the 35kV high-voltage switchgear A via a second 35kV high-voltage cable 15. The 35kV busbar 1 within the 35kV high-voltage switchgear A is used for connections between the 35kV system busbars. The energy storage unit 12 is equipped with the second 35kV load switch 16 and the second 35kV fuse 17 on its high-voltage side, and is connected to the outgoing terminal of the 35kV switchgear via a first 35kV high-voltage cable 9. When the 35kV station service transformer 18 fails, the second 35kV fuse 17 trips, without affecting the normal operation of the energy storage system B branch circuit. When the energy storage system B fails, the first 35kV fuse 11 trips, without affecting the normal operation of the box-type station service transformer system C branch circuit. Faults outside the protection range of the first 35kV fuse 11 and the second 35kV fuse 17 cause the handcart-type circuit breaker 2 in the 35kV high-voltage switchgear A to trip. At this time, the station service transformer loses power, and the station service load is powered by the backup power supply, which basically does not affect the normal operation of the power station. It should be noted that this invention reduces one 35kV switchgear by changing the wiring method, saving investment.

[0025] According to the power flow direction, the rated current of the 35kV high-voltage switchgear A should include the current of the prefabricated substation transformer system C and the energy storage system B. Its rated current is considered under maximum operating conditions, i.e., the sum of the rated currents of the prefabricated substation transformer system C and the energy storage system B. The circuit current of the prefabricated substation transformer system C is very small, typically less than 20A. Therefore, the rated current of the 35kV high-voltage switchgear A is mainly affected by the current carrying capacity of the energy storage system B. In this novel invention, the rated current of the main circuit can be calculated by adding 20A to the rated current of the energy storage system B.

[0026] In this invention, the box-type substation transformer system C and the energy storage system B are independent of each other, and normal maintenance only requires disconnecting the load switch on this side;

[0027] This invention can reduce the number of 35kV switchgear in a new energy power station of the same scale. One 35kV switchgear can connect to 25MW of new energy power generation capacity. It can be applied in the development and construction of new energy projects with limited land use and expansion. It has the characteristics of simple principle, convenient operation and strong practicality, and has broad promotion value. It can effectively improve the economy of existing systems.

Claims

1. A novel 35kV feeder shared system, characterized in that, It includes a 35kV high-voltage switchgear (A), an energy storage system (B), and a prefabricated substation transformer system (C); the 35kV high-voltage switchgear (A) is connected to the energy storage system (B) and the prefabricated substation transformer system (C); The 35kV high-voltage switchgear (A) includes a 35kV busbar (1), a handcart-type circuit breaker (2), an electromagnetic current transformer (3), a first 35kV high-voltage cable terminal (71), and a third 35kV high-voltage power cable (131). The 35kV busbar (1) is divided into two paths after passing through the handcart-type circuit breaker (2) and the electromagnetic current transformer (3). One path is connected to the energy storage system (B) via the first 35kV high-voltage cable terminal (71), and the other path is connected to the box-type substation transformer system (C) via the third 35kV high-voltage power cable (131). The 35kV busbar (1) is grounded through a handcart-type circuit breaker (2) and an electromagnetic current transformer (3) and then through a high-voltage surge arrester (4). The 35kV busbar (1) is grounded through a handcart-type circuit breaker (2) and an electromagnetic current transformer (3) and then through a grounding switch (5); The 35kV busbar (1) is grounded through a handcart-type circuit breaker (2) and an electromagnetic current transformer (3) and then through a live display (6). The energy storage system (B) includes a second 35kV high-voltage cable terminal (72), a first 35kV high-voltage cable (9), a first 35kV load switch (10), a first 35kV fuse (11), and an energy storage complete unit (12); the first 35kV high-voltage cable terminal (71) is connected to the energy storage complete unit (12) via the first 35kV high-voltage cable (9), the second 35kV high-voltage cable terminal (72), the first 35kV load switch (10), and the first 35kV fuse (11); The first 35kV high-voltage cable (9) is equipped with a first zero-sequence current transformer (8). The box-type substation transformer system (C) includes a fourth 35kV high-voltage power cable (132), a second 35kV high-voltage cable (15), a second 35kV load switch (16), a second 35kV fuse (17), and a 35kV substation transformer (18). The third 35kV high-voltage power cable (131) is connected to the 35kV station transformer (18) via the second 35kV high-voltage power cable (15), the fourth 35kV high-voltage power cable (132), the second 35kV load switch (16) and the second 35kV fuse (17); A second zero-sequence current transformer (14) is installed on the second 35kV high-voltage cable (15).

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