A bipolar short-circuit test layout structure for an HVDC converter station on an island

Abstract

A bipolar short-circuit test device for an HVDC converter station on an island, comprising an outdoor DC yard inside the station and a short-circuit test yard outside the station. The original positive and negative line outlets of the HVDC converter station on the island are led to the short-circuit test yard outside the station through the outdoor DC yard for bipolar short-circuit tests. The outdoor DC yard inside the station mainly includes smoothing reactors, resistor-capacitor voltage dividers, DC line arresters, a first cable terminal connected to the indoor DC yard through a submarine cable, and a second cable terminal connected to the short-circuit test yard outside the station. The short-circuit test yard outside the station mainly includes post insulators, aluminum-magnesium alloy pipes, and a third cable terminal connected to the outdoor DC yard inside the station through a submarine cable. The post insulators support the aluminum-magnesium alloy pipes and are arranged in two columns at the middle position of the short-circuit test yard outside the station, forming the positive and negative poles of the short-circuit test. Third cable terminals are respectively arranged corresponding to the east side and the south side of the post insulators. A non-metallic fence is arranged in a circle around the short-circuit test yard outside the station.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric power, and particularly relates to a bipolar short-circuit test plane layout structure for an island flexible DC converter station. Background Art

[0002] Flexible DC power transmission is a new type of power transmission technology based on power electronics technology, and has strong advantages in aspects such as island power supply, urban distribution network capacity expansion, and wind power grid connection. Among them, DC circuit breakers and converter valves are the hearts of flexible DC converter stations. The bipolar short-circuit test is an effective means to verify the operation reliability of DC circuit breakers and converter valves. At present, there is no engineering experience in conducting on-site bipolar short-circuit tests at home and abroad. Due to the special terrain of the island, the DC pole lines of the on-island flexible DC converter station generally use submarine cables for outgoing lines, which is different from the convenient connection of overhead outgoing lines. Therefore, it is urgent to study the layout scheme of the on-site bipolar short-circuit test for the flexible DC converter station, fill the engineering gap of the short-circuit test for the flexible DC converter station, and provide a reference for the design of the short-circuit test scheme for the flexible DC converter station in the future. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a bipolar short-circuit test plane layout structure suitable for an island flexible DC converter station in view of the above-mentioned defects of the prior art.

[0004] The object of the present invention is achieved by the following technical solutions. A bipolar short-circuit test plane layout structure for an island flexible DC converter station, the plane layout structure includes an outdoor DC field inside the station and a short-circuit test field outside the station. The original positive and negative pole line outlets of the island flexible DC converter station are led to the short-circuit test field outside the station through the outdoor DC field inside the station for bipolar short-circuit tests.

[0005] Further, the outdoor DC field inside the station mainly includes smoothing reactors, resistor-capacitor voltage dividers, DC pole line arresters, a first cable terminal, and a second cable terminal. The smoothing reactor group is arranged in a straight line at the middle position of the outdoor DC field inside the station. On the east and west sides of the smoothing reactor, DC pole line arresters, resistor-capacitor voltage dividers, and the second cable terminal are symmetrically arranged in sequence. The first cable terminal is arranged on the south side of the smoothing reactor. The first cable terminal is connected to the cable terminal at the outlet of the original indoor DC field through a submarine cable. The second cable terminal is connected to the short-circuit test field outside the station through a submarine cable. The original positive and negative pole lines of the island flexible DC converter station are connected to the first cable terminal of the outdoor DC field inside the station through submarine cables, and then sequentially pass through the smoothing reactor, DC pole line arrester, and resistor-capacitor voltage divider, and finally are connected to the short-circuit test field outside the station by the second cable terminal.

[0006] Furthermore, the off-site short-circuit test field mainly includes post insulators, aluminum-magnesium alloy pipes, and third cable terminals. The post insulators support the aluminum-magnesium alloy pipes and are arranged in two rows at the middle position of the off-site short-circuit test field, forming the positive and negative poles of the short-circuit test. Third cable terminals are respectively arranged on the east side and the south side of the post insulators; the third cable terminals are connected to the second cable terminals of the in-station outdoor DC field through submarine cables.

[0007] Furthermore, a non-metallic fence is arranged around the off-site short-circuit test field, and a main grounding grid is laid on the ground inside the fence.

[0008] The beneficial technical effects of the present invention are as follows: The bipolar short-circuit test plane layout structure of the present invention has a high space utilization rate, can fill the engineering gap of the short-circuit test of the flexible DC converter station, and provides a reference for the design of the short-circuit test scheme of the flexible DC converter station in the future. Description of the Drawings

[0009] Figure 1 is the plane layout drawing of the in-station outdoor DC field of the present invention;

[0010] Figure 2 is the plane layout drawing of the off-site short-circuit test field of the present invention. Detailed Embodiments

[0011] To enable those of ordinary skill in the art to more clearly understand the purpose, technical solutions, and advantages of the present invention, the following further elaborates on the present invention with reference to the drawings and embodiments.

[0012] As Figure 1-2 shown, a bipolar short-circuit test plane layout structure of a sea-island flexible DC converter station according to the present invention, the plane layout structure includes an in-station outdoor DC field 1 and an off-site short-circuit test field 2. The original positive and negative line outlets of the sea-island flexible DC converter station are led to the off-site short-circuit test field 2 through the in-station outdoor DC field 1 for short-circuit tests.

[0013] Refer to Figure 1As shown in the figure, the in-station outdoor DC field 1 mainly includes a smoothing reactor 11, a resistor-capacitor voltage divider 12, a DC pole line arrester 13, a first cable terminal 14, and a second cable terminal 15. The smoothing reactor 11 is arranged in a straight line at the middle position of the in-station outdoor DC field 1. On the east and west sides of the smoothing reactor 11, the DC pole line arrester 13, the resistor-capacitor voltage divider 12, and the second cable terminal 15 are symmetrically arranged in sequence. On the south side of the smoothing reactor 11, the first cable terminal 14 is arranged. The original positive and negative pole lines of the Hainan flexible DC converter station are connected to the first cable terminal 14 of the in-station outdoor DC field 1 through submarine cables, then pass through the smoothing reactor 11, the DC pole line arrester 13, and the resistor-capacitor voltage divider 12 in sequence, and finally are connected to the out-of-station short-circuit test field by the second cable terminal 15. The layout of the in-station outdoor DC field 1 ensures the safety of the converter valves and DC circuit breakers during the short-circuit test on the one hand, and measures the electrical quantities required during the short-circuit test on the other hand.

[0014] Refer to Figure 2 As shown in the figure, the out-of-station short-circuit test field 2 mainly includes post insulators 21, aluminum-magnesium alloy pipes 22, and a third cable terminal 23. The post insulators 21 support the aluminum-magnesium alloy pipes 22 and are arranged in two rows at the middle position of the out-of-station short-circuit test field 2, forming the positive and negative poles of the short-circuit test. The third cable terminals 23 are respectively arranged on the east side and the south side of the post insulators 21. The third cable terminal 23 is connected to the second cable terminal 15 of the in-station outdoor DC field 1 through a submarine cable. Considering the personnel operation and safety distance during the short-circuit test, a non-metallic fence 24 is arranged around the out-of-station short-circuit test field 2, and a main grounding grid is laid on the ground inside the fence 24 to ensure that the step voltage and touch voltage meet the specification requirements.

[0015] Taking the bipolar short-circuit test plane layout structure of Zhoushan ±200kV Dinghai Converter Station as an example for elaboration. The DC field of the ±200kV Dinghai Converter Station is arranged indoors, and submarine cables are used for outgoing lines to connect to Daishan Station. Since it does not have the convenient connection characteristics of overhead outgoing lines, the method of leading the pole line outside the station is adopted for the short-circuit test. Two distribution device areas, namely the in-station outdoor DC field and the out-of-station short-circuit test field, are added.

[0016] The plane layout of the in-station outdoor DC field is as Figure 1 shown. The smoothing reactor is arranged in a straight line in the middle, and the DC pole line arrester, the resistor-capacitor voltage divider, and the cable terminal are symmetrically arranged on the east and west sides, and the cable terminal is arranged on the south side. The original positive and negative pole lines of the indoor DC field are connected to the cable terminal on the south side of the outdoor DC field through submarine cables, pass through the smoothing reactor, the DC pole line arrester, and the resistor-capacitor voltage divider in sequence, and finally are connected to the out-of-station short-circuit test field through the cable terminals on the east and west sides by submarine cables.

[0017] The plane layout of the out-of-station short-circuit test field is as Figure 2As shown, four post insulators support two aluminum-magnesium alloy pipes, which are arranged in two rows in the exact middle of the short-circuit test field, forming the positive and negative poles of the short-circuit test. Two outdoor cable terminals are arranged on the south side and the east side and are connected to the outdoor DC field in the station through submarine cables.

[0018] The specific embodiments described in this document are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A bipolar short-circuit test device for an HVDC converter station on an island, characterized in that: The device includes an outdoor DC yard inside the station and a short-circuit test yard outside the station. The original positive and negative line outlets of the HVDC converter station on the island are led to the short-circuit test yard outside the station through the outdoor DC yard inside the station for bipolar short-circuit tests. The outdoor DC yard inside the station mainly includes smoothing reactors, RC voltage dividers, DC line arresters, first cable terminals, and second cable terminals. The smoothing reactors are arranged in a straight line at the middle position of the outdoor DC yard inside the station. On the east and west sides of the smoothing reactors, DC line arresters, RC voltage dividers, and second cable terminals are symmetrically arranged in sequence. The first cable terminal is arranged on the south side of the smoothing reactor. The first cable terminal is connected to the cable terminal at the outlet of the original indoor DC yard through a submarine cable. The second cable terminal is connected to the short-circuit test yard outside the station through a submarine cable. The original positive and negative lines of the HVDC converter station on the island are connected to the first cable terminal of the outdoor DC yard inside the station through a submarine cable, then pass through the smoothing reactor, DC line arrester, and RC voltage divider in sequence, and finally are connected to the short-circuit test yard outside the station by the second cable terminal. The short-circuit test yard outside the station mainly includes post insulators, aluminum-magnesium alloy pipes, and third cable terminals. The post insulators support the aluminum-magnesium alloy pipes and are arranged in two rows at the middle position of the short-circuit test yard outside the station, forming the positive and negative poles of the short-circuit test. Third cable terminals are respectively arranged on the east side and the south side of the post insulators. The third cable terminals are connected to the second cable terminals of the outdoor DC yard inside the station through submarine cables. There are 4 post insulators. The 4 post insulators support 2 aluminum-magnesium alloy pipes and are arranged in two rows right in the middle of the short-circuit test yard, forming the positive and negative poles of the short-circuit test. Two outdoor cable terminals are arranged on the south side and the east side and are connected to the outdoor DC yard inside the station through submarine cables.

2. The bipolar short-circuit test device according to claim 1, characterized in that: A non-metallic fence is set around the short-circuit test yard outside the station, and a main grounding grid is laid on the ground inside the fence.

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