Protection methods, systems, and media for high-voltage transmission lines connected in different ways.

Abstract

This invention discloses a protection method, system, and medium for offshore wind power transmission lines with different access methods for energy extraction high-voltage reactors. The protection method for these systems includes: determining the wiring configuration of the energy extraction high-voltage reactor in the transmission line, wherein the reactor is installed in the offshore power grid system; determining the protection configuration method for the offshore power grid system based on the wiring configuration; and determining the protection action logic for the offshore power grid system based on the protection configuration method. This invention solves the problem of achieving reliable tripping of protection systems on both sides of the transmission line in scenarios where energy extraction high-voltage reactors are accessed in different ways, providing a reliable technical solution for offshore wind power transmission and significantly improving the absorption capacity of new energy sources.

Description

Technical Field

[0001] This invention relates to the field of relay protection technology, and in particular to a protection method, system and medium for high-voltage transmission lines with different energy extraction methods. Background Technology

[0002] Currently, the main form of offshore wind power grid connection in China is to connect the offshore wind farm's voltage to an onshore substation via AC submarine cables. As the distance from the shore to the offshore wind farm increases, the length of the submarine cables also increases. The capacitive effect of long-distance submarine cables will generate a large amount of reactive power, which not only reduces the effective load capacity of the cables but also raises the voltage of the power grid system, seriously threatening the safe operation of equipment. Therefore, it is necessary to configure high-voltage reactors to balance the reactive power generated by the cables. The location for these reactors can be a newly built offshore high-voltage reactor station at the outlet of the offshore substation, on the side of the onshore substation, or somewhere in between. For newly built offshore high-voltage reactor stations, due to remote locations and difficulties in power supply, pump-type reactors are used to provide stable low-voltage power to the station. At the same time, to save costs and reduce the footprint, offshore high-voltage reactor stations may connect directly to the submarine cable via disconnect switches without circuit breakers. For offshore high-voltage reactor substations with their pumping reactors directly connected to the submarine cable via disconnect switches, traditional transmission line protection configurations with parallel reactors are difficult to apply when there is a fault in the T-zone, the pumping reactor, or the high-voltage side switch of the station's auxiliary transformer fails. This is because the pumping reactor is not connected to the submarine cable line via a circuit breaker. Achieving tripping protection on both sides of the submarine cable is a major challenge. Adding signal receiving devices to the offshore booster station, offshore high-voltage reactor substation, and onshore booster station would allow the pumping reactor protection or the high-voltage side switch failure protection to send the protection action signal to the receiving devices on both sides of the submarine cable via the offshore high-voltage reactor substation receiving device. This signal would then be sent through the circuit breaker's control box to trip the switches on both sides of the submarine cable. However, this method carries the risk of accidental tripping of the submarine cable line due to erroneous input from the receiving devices at the offshore or onshore booster stations.

[0003] There is currently no effective solution to the technical problem that the traditional transmission line protection configuration method with parallel reactors is difficult to apply to the direct connection of the high-energy-draining reactor to the outgoing submarine cable via a disconnecting switch. Summary of the Invention

[0004] The embodiments of this disclosure provide a protection method, system, and medium for accessing the power extraction high-voltage reactor to the transmission line in different ways, so as to at least solve the technical problem that the traditional transmission line protection configuration method with parallel reactor is difficult to apply to the direct access of the power extraction high-voltage reactor to the transmission submarine cable by disconnecting switch in the prior art.

[0005] According to one aspect of the present disclosure, a protection method for connecting a high-voltage collector to a transmission line in different ways is provided, comprising: determining the wiring configuration of the high-voltage collector connected to the transmission line, wherein the high-voltage collector is installed in a marine power grid system; determining a protection configuration method for the marine power grid system based on the wiring configuration; and determining the protection action logic for the marine power grid system based on the protection configuration method.

[0006] Optionally, the wiring configuration includes connection to the transmission line without a circuit breaker and connection to the transmission line with a circuit breaker. The offshore power grid system includes the offshore substation bus, the transmission line, the offshore high-voltage reactor station, and the onshore substation bus. Based on the wiring configuration, the operation of determining the protection configuration method of the offshore power grid system includes: when the wiring configuration is connection to the transmission line without a circuit breaker, determining the first protection configuration method for the transmission line, the offshore substation bus, and the onshore substation bus; and determining the second protection configuration method for the offshore high-voltage reactor station.

[0007] Optionally, the operation of determining the first protection configuration method for the transmission line, the offshore substation busbar, and the onshore substation busbar includes: configuring a dual differential protection system on the transmission line, wherein the differential protection system is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage and remote tripping protection functions, and the local criteria for remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power; and configuring a dual differential protection system for the transmission line from the offshore high-voltage substation to the offshore substation busbar. The substation and the offshore high-voltage reactor substation are equipped with dual differential protection between the substation and the onshore substation. The differential protection is equipped with differential protection, grounding and phase-to-phase distance protection, zero-sequence overcurrent protection, reclosing and overvoltage protection, and remote tripping protection. The local criteria for remote tripping protection include current change, zero negative sequence current, zero negative sequence voltage, low current, low power factor, and low active power. Dual bus differential protection is configured for the busbars connecting the transmission lines to the offshore substation and the busbars connecting the transmission lines to the onshore substation.

[0008] Optionally, the operation of determining the second protection configuration method for the offshore high-voltage reactor station includes: configuring dual bus differential protection for the T-section formed by the transmission line connected to the offshore high-voltage reactor station; configuring dual electrical quantity protection and a single set of non-electrical quantity protection for the pumping high-voltage reactor, wherein the electrical quantity protection includes main reactor differential protection / inter-turn protection / overcurrent protection / overload alarm / zero-sequence overcurrent protection / pumping side differential protection / pumping side inter-turn protection / pumping side winding overvoltage overcurrent / pumping side switch overvoltage overcurrent / pumping side winding zero-sequence overcurrent function; configuring a single set of transformer protection for the low-voltage station transformer connected to the pumping side of the pumping reactor of the offshore high-voltage reactor station, wherein the single set of transformer protection includes longitudinal differential protection / instantaneous overcurrent / overcurrent protection function; and configuring switch failure protection for the circuit breaker connected to the high-voltage side of the low-voltage station transformer.

[0009] Optionally, the operation of determining the protection action logic of the offshore power grid system according to the protection configuration method includes: determining the first protection action logic of the transmission line, the offshore substation busbar, and the onshore substation busbar when the connection method is to connect to the transmission line without passing through the circuit breaker; and determining the second protection action logic of the offshore high-voltage anti-substation.

[0010] Optionally, the operation of determining the first protection action logic for the sending line, the offshore substation bus, and the onshore substation bus includes: in the event of a fault in the sending line between the offshore high-voltage reactor station and the offshore substation / a fault in the sending line between the offshore high-voltage reactor station and the onshore substation, the differential protection function of the large differential protection trips the switches on both sides of the sending line; the differential protection function of the small differential protection on the offshore substation side trips the switch on the offshore substation side / the differential protection function of the small differential protection on the onshore substation side trips the switch on the onshore substation side; the small differential protection on the offshore high-voltage reactor station side sends a trip signal to the small differential protection device on the offshore high-voltage reactor station side within the protection range of the sending line between the offshore high-voltage reactor station and the onshore substation. The differential protection sends a trip signal to the small differential protection device on the offshore high-voltage reactor side within the protection range of the outgoing line from the offshore high-voltage reactor station to the offshore substation. It also sends a remote trip signal. After the local remote trip criterion of the small differential protection on the onshore substation side is met, the switch on the onshore substation side is tripped. In the event of a fault on the high-voltage busbar of the offshore substation or the high-voltage busbar of the onshore substation, the bus differential protection trips all switches connected to the high-voltage busbar of the offshore substation or the high-voltage busbar of the onshore substation. Furthermore, it remotely trips the switches on the outgoing line of the onshore substation or the outgoing line of the offshore substation through the large differential protection of the outgoing line.

[0011] Optionally, the operation of determining the second protection action logic of the offshore high-voltage reactor station includes: in the event of a fault in the T-section / energy-extraction high-voltage reactor connected to the transmission line of the offshore high-voltage reactor station, the trip signals of the bus differential protection / electrical quantity protection of the T-section / energy-extraction high-voltage reactor are respectively sent to the remote transmission 1 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and the remote transmission 1 signal is sent to the differential protection of the opposite line to generate a trip signal, and this trip signal simultaneously activates the switch failure protection of the opposite side; in the event of a fault on the low-voltage side of the station service transformer, the high-voltage side switch failure / energy-extraction high-voltage reactor non-electrical quantity protection is activated, the action signals of the switch failure protection / energy-extraction high-voltage reactor non-electrical quantity protection are respectively sent to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and the remote transmission 2 signal is sent to the differential protection of the opposite line to generate a trip signal, and this trip signal does not activate the switch failure protection of the opposite side.

[0012] Optionally, the operation of determining the protection configuration method of the offshore power grid system according to the wiring configuration further includes: determining the third protection configuration method of the transmission line, the offshore substation busbar and the onshore substation busbar when the wiring configuration is connected to the transmission line via a circuit breaker; and determining the fourth protection configuration method of the offshore high-voltage anti-seismic station.

[0013] Optionally, the operation of determining the third protection configuration method for the transmission lines, offshore substation busbars, and onshore substation busbars includes: configuring dual differential protection for the transmission lines between the offshore high-voltage reactor station and the offshore substation, and for the transmission lines between the offshore high-voltage reactor station and the onshore substation, wherein the differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions, and the local criteria for remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power; configuring dual bus differential protection for the offshore substation busbars and the onshore substation busbars connected to the transmission lines.

[0014] Optionally, the operation of determining the fourth protection configuration method for the offshore high-voltage reactor station includes: configuring dual bus differential protection for the T-section formed by the offshore high-voltage reactor station's connection to the transmitting line; configuring dual electrical quantity protection and a single set of non-electrical quantity protection for the pumping reactor, wherein the electrical quantity protection includes main reactor differential protection / inter-turn protection / overcurrent protection / overload alarm / zero-sequence overcurrent protection / pumping side differential protection / pumping side inter-turn protection / pumping side winding overvoltage overcurrent / pumping side switch overvoltage overcurrent / pumping side winding zero-sequence overcurrent function; configuring a single set of transformer protection for the low-voltage station transformer connected to the pumping side of the offshore high-voltage reactor station's pumping reactor, wherein the single set of transformer protection includes longitudinal differential protection / instantaneous overcurrent / overcurrent protection function; and configuring switch failure protection for the circuit breaker connected to the high-voltage side of the low-voltage station transformer.

[0015] Optionally, based on the protection configuration method, the operation of determining the protection action logic of the offshore power grid system includes: determining the third protection action logic of the transmission line, the offshore substation bus, and the onshore substation bus when the connection method is to connect to the transmission line via a circuit breaker; and determining the fourth protection action logic of the offshore high-voltage anti-seismic station.

[0016] Optionally, the operation of the third protection action logic for the sending line, the offshore substation busbar, and the onshore substation busbar includes: in the event of a fault in the sending line from the offshore high-voltage reactor station to the offshore substation / in the event of a fault in the sending line from the offshore high-voltage reactor station to the onshore substation, the differential protection function in the small differential protection quickly trips the switches on the offshore substation side and the offshore high-voltage reactor station side / the differential protection function in the small differential protection quickly trips the switches on the onshore substation side and the offshore high-voltage reactor station side; in the event of a fault in the high-voltage busbar of the offshore substation / in the event of a fault in the high-voltage busbar of the onshore substation, the bus differential protection quickly trips the switches of all branches connected to the high-voltage busbar, and remotely trips the switch of the opposite offshore high-voltage reactor station through the small differential protection of the sending line.

[0017] Optionally, the operation of determining the fourth protection action logic of the offshore high-voltage reactor station includes: when a fault occurs in the T-section / energy-extraction high-voltage reactor formed by the transmission line connected to the offshore high-voltage reactor station, the electrical quantity protection of the bus differential protection / energy-extraction high-voltage reactor of the T-section quickly trips the two switches of the offshore high-voltage reactor station. At the same time, the trip signal of the electrical quantity protection of the bus differential protection / energy-extraction high-voltage reactor of the T-section is respectively sent to the remote transmission 1 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and the remote transmission 1 signal is sent to the differential protection of the opposite line to generate a trip signal, and this trip... The signal simultaneously activates the switch failure protection on the opposite side; in the event of a fault on the low-voltage side of the station transformer, the switch failure protection / energy extraction high-resistance non-electrical quantity protection trips the two switches of the offshore high-resistance station. At the same time, the operation signal of the switch failure protection / energy extraction high-resistance non-electrical quantity protection is respectively sent to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-resistance station, and the remote transmission 2 signal is sent to the differential protection of the opposite line to generate a trip signal. This trip signal does not activate the switch failure protection on the opposite side.

[0018] According to another aspect of the present disclosure, a storage medium is also provided, the storage medium including a stored program, wherein, when the program is executed, a processor performs any of the methods described above.

[0019] According to another aspect of the present disclosure, a protection system for accessing the power extraction high-voltage reactor to the transmission line in different ways is also provided, comprising: a first determining module, configured to determine the wiring form of the power extraction high-voltage reactor accessing the transmission line, wherein the power extraction high-voltage reactor is installed in the offshore power grid system; a second determining module, configured to determine the protection configuration method of the offshore power grid system according to the wiring form; and a third determining module, configured to determine the protection action logic of the offshore power grid system according to the protection configuration method.

[0020] In this embodiment, the present invention provides a protection method for different methods of connecting the energy-extracting high-voltage reactor to the transmission line. The method determines the wiring configuration of the energy-extracting high-voltage reactor to the transmission line, determines the protection configuration method for the offshore power grid system based on the wiring configuration, and then determines the protection operation logic for the offshore power grid system based on the protection configuration method. Therefore, for two wiring configurations—one where the energy-extracting high-voltage reactor is directly connected to the transmission line via a disconnecting switch without a circuit breaker, and the other where the energy-extracting high-voltage reactor is connected to the transmission line via a circuit breaker—corresponding protection configuration methods and protection operation logic are proposed respectively. This solves the problem of how to reliably trip the protection on both sides of the transmission line when there is a fault in the T-zone interval within the offshore high-voltage reactor station, a fault in the energy-extracting high-voltage reactor, or a fault in the station's auxiliary transformer and a failure of the high-voltage side switch. It also solves the technical problem that the traditional transmission line protection configuration method with parallel reactors is difficult to apply to the direct connection of the energy-extracting high-voltage reactor to the submarine cable via a disconnecting switch in the prior art. Attached Figure Description

[0021] The accompanying drawings, which are included to provide a further understanding of this disclosure and form part of this invention, illustrate exemplary embodiments of the present disclosure and are used to explain the disclosure, but do not constitute an undue limitation thereof. In the drawings:

[0022] Figure 1 This is a hardware structure block diagram of a computing device for implementing the method described in Embodiment 1 of this disclosure;

[0023] Figure 2 This is a flowchart illustrating the protection method for accessing the transmission line in different ways according to the first aspect of Embodiment 1 of this disclosure;

[0024] Figure 3 This is another schematic flowchart of the protection method for accessing the transmission line in different ways according to Embodiment 1 of this disclosure;

[0025] Figure 4 This is a schematic diagram of the energy extraction high-resistance circuit directly connected to the transmission line without passing through a circuit breaker and using an isolating switch, according to Embodiment 1 of this disclosure;

[0026] Figure 5 This is a schematic diagram of the energy extraction high-resistance circuit breaker connected to the transmission line according to Embodiment 1 of this disclosure;

[0027] Figure 6 This is a schematic diagram of the protection configuration when the high-voltage pumping reactor is directly connected to the transmission line without passing through a circuit breaker, according to Embodiment 1 of this disclosure;

[0028] Figure 7 This is a schematic diagram of the protection configuration when the energy extraction high-resistance circuit breaker is connected to the transmission line according to Embodiment 1 of this disclosure;

[0029] Figure 8This is a schematic diagram of the operation logic of the line protection when the high-energy-absorbing reactor is connected to the transmission line via a disconnecting switch according to Embodiment 1 of this disclosure;

[0030] Figure 9 This is a schematic diagram of the operation logic of the marine high-voltage protection station when the energy extraction high-voltage reactor is connected to the transmission line via a disconnecting switch according to Embodiment 1 of this disclosure;

[0031] Figure 10 This is a schematic diagram of the operation logic of the line protection when the high-resistance energy extraction circuit breaker is connected to the transmission line according to Embodiment 1 of this disclosure;

[0032] Figure 11 This is a schematic diagram of the operation logic of the marine high-resistance station protection when the energy extraction high-resistance is connected to the transmission line via a circuit breaker according to Embodiment 1 of this disclosure;

[0033] Figure 12 This is a schematic diagram of a protection system for high-energy extraction and high-resistance transmission lines accessed in different ways according to Embodiment 2 of this disclosure. Detailed Implementation

[0034] To enable those skilled in the art to better understand the technical solutions of this disclosure, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this disclosure described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] Example 1

[0037] According to this embodiment, a protection method embodiment for high-energy-absorbing transmission lines accessed in different ways is also provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than that shown here.

[0038] The method embodiments provided in this example can be executed on mobile terminals, computer terminals, servers, or similar computing devices. Figure 1 A hardware block diagram of a computing device is shown for implementing a protection method for high-resistance power extraction lines accessed in different ways. (See diagram for example.) Figure 1 As shown, a computing device may include one or more processors (processors may include, but are not limited to, microprocessors such as MCUs or programmable logic devices such as FPGAs), memory for storing data, and transmission devices for communication functions. In addition, it may also include: a display, input / output interfaces (I / O interfaces), a universal serial bus (USB) port (which may be included as one of the ports in the I / O interface), a network interface, a power supply, and / or a camera. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the aforementioned electronic device. For example, a computing device may also include... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown.

[0039] It should be noted that the aforementioned one or more processors and / or other data processing circuits are generally referred to herein as "data processing circuits". These data processing circuits may be embodied, in whole or in part, in software, hardware, firmware, or any other combination thereof. Furthermore, the data processing circuits may be a single, independent processing module, or may be integrated, in whole or in part, into any other element in a computing device. As involved in the embodiments of this disclosure, the data processing circuits serve as processor control (e.g., selection of a variable resistor termination path connected to an interface).

[0040] The memory can be used to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the energy-saving protection method for high-resistance to different access methods of the transmission line in the embodiments of this disclosure. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory, thereby realizing the energy-saving protection method for high-resistance to different access methods of the transmission line described above. The memory may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory may further include memory remotely located relative to the processor, and these remote memories can be connected to the computing device via a network. Examples of the above-mentioned networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0041] The transmission device is used to receive or send data via a network. Specific examples of the network described above may include a wireless network provided by the computing device's communications provider. In one example, the transmission device includes a Network Interface Controller (NIC), which can connect to other network devices via a base station to communicate with the Internet. In another example, the transmission device may be a Radio Frequency (RF) module, used for wireless communication with the Internet.

[0042] The display can be, for example, a touchscreen liquid crystal display (LCD), which allows users to interact with the user interface of the computing device.

[0043] It should be noted here that, in some optional embodiments, the above... Figure 1 The computing device shown may include hardware elements (including circuitry), software elements (including computer code stored on a computer-readable medium), or a combination of both hardware and software elements. It should be noted that... Figure 1 This is only one instance of a specific particular instance, and is intended to illustrate the types of components that may exist in the aforementioned computing devices.

[0044] Under the above operating environment, according to the first aspect of this embodiment, a protection method for high-resistance energy extraction lines accessed in different ways is provided. Figure 2 A flowchart illustrating the method is shown below. (Refer to...) Figure 2 As shown, the method includes:

[0045] S201: Determine the wiring configuration for the high-voltage pumping reactor connected to the transmission line, with the high-voltage pumping reactor installed in the offshore power grid system;

[0046] S202: Determine the protection configuration method for the offshore power grid system based on the wiring configuration;

[0047] S203: Determine the protection action logic of the offshore power grid system according to the protection configuration method.

[0048] Specifically, such as Figure 3 As shown, Figure 3 This is another flowchart of the present invention. The present invention provides a protection method for high-resistance power extraction lines accessed in different ways, the method comprising the following steps:

[0049] Step 1: Determine the specific wiring configuration for the high-voltage reactor to be connected to the transmission line;

[0050] Step 2: When the high-voltage reactor is directly connected to the outgoing line via a disconnector without passing through a circuit breaker, determine the protection configuration method under this wiring configuration;

[0051] Step 3: Determine the protection operation logic when the high-voltage reactor is connected to the outgoing line without passing through the circuit breaker and via a disconnecting switch;

[0052] Step 4: When the high-voltage reactor is connected to the transmission line via the circuit breaker, determine the protection configuration method under this wiring configuration;

[0053] Step 5: Determine the protection operation logic when the high-energy-absorbing reactor is connected to the transmission line via the circuit breaker.

[0054] In step 1, the specific wiring configuration for the extraction high-voltage reactor to the transmission line needs to be determined based on the actual site conditions. In practical engineering, the extraction high-voltage reactor is usually connected in the middle area of ​​the transmission line, unlike ordinary parallel reactors which are connected to both sides of the line. This is because when the extraction high-voltage reactor is located in the middle area of ​​the transmission line, the power supply in the offshore high-voltage reactor station can be provided by the extraction winding itself, without the need for a transformer at an additional high-voltage station or long-distance power transmission from other adjacent substations, thus saving significant costs. When the extraction high-voltage reactor is built offshore, to reduce the land area and construction costs, it can be connected to the submarine cable line without a circuit breaker by using a disconnecting switch. Therefore, the forms of connection of the extraction high-voltage reactor to the transmission line include two types: direct connection without a circuit breaker using a disconnecting switch and connection via a circuit breaker, as shown below. Figure 4 and Figure 5 As shown.

[0055] Step 2 specifically includes the following steps:

[0056] Step 2-1: When the high-voltage reactor is directly connected to the transmission line via a disconnector without passing through a circuit breaker, determine the protection configuration method for the transmission line and the busbars connected to both sides of the transmission line.

[0057] Step 2-2: When the high-voltage reactor is connected to the transmission line directly via a disconnector without a circuit breaker, determine the protection configuration method for the offshore high-voltage reactor station.

[0058] In step 2-1, the protection configuration method for the sending line and the busbars connected to both sides of the sending line is as follows:

[0059] Generally, the voltage levels of high-voltage pumping reactors connected to transmission lines are 220kV and 500kV, which are high-voltage levels. Figure 6 As shown, the transmitting lines require separate configurations for both large and small differential protection. The large differential protection is a longitudinal current differential protection system capable of protecting the entire transmitting line. It requires a dual configuration, with each set of protection equipped with differential protection, grounding and phase-to-phase distance protection, zero-sequence overcurrent protection, reclosing and overvoltage protection, and remote tripping protection. The local criteria for remote tripping protection include current change, zero-negative-sequence current, zero-negative-sequence voltage, low current, low power factor, and low active power. Lines between the offshore high-voltage reactor station and the offshore substation, as well as lines between the offshore high-voltage reactor station and the onshore substation, require dual sets of small differential protection. The protection range of the small differential protection extends from the offshore high-voltage reactor station to the substations on both sides. The configuration of the small differential protection functions is the same as the large differential protection; however, only the longitudinal differential protection function needs to be activated, while the other protection functions are deactivated. Both the offshore and onshore substation busbars connected to the transmitting line must be equipped with dual bus differential protection. When the transmitting line is at a voltage level of 220kV, the bus differential protection must be equipped with switch failure protection. The configuration of the line's large differential protection, small differential protection, and the bus differential protection of the substations on both sides must ensure the elimination of protection dead zones.

[0060] In step 2-2, the protection configuration method for the offshore high-altitude anti-tank station is as follows:

[0061] like Figure 6 As shown, the T-section formed by the offshore high-voltage reactor station connected to the transmission line requires dual bus differential protection. The pumping reactor needs dual electrical quantity protection, including main reactor differential protection, inter-turn protection, overcurrent protection, overload alarm, and zero-sequence overcurrent protection. It also includes pumping-side differential protection, pumping-side inter-turn protection, pumping-side winding overvoltage overcurrent protection, pumping-side switch overvoltage overcurrent protection, and pumping-side winding zero-sequence overcurrent protection. Simultaneously, the pumping reactor also needs a single set of non-electrical quantity protection. The low-voltage station transformer connected to the pumping side of the pumping reactor needs a single set of transformer protection, including longitudinal differential protection, instantaneous trip protection, and overcurrent protection. The circuit breaker connected to the high-voltage side of the station transformer needs switch failure protection. When configuring the line differential protection, T-section bus differential protection, and pumping high-voltage reactor protection, it is necessary to ensure the elimination of protection dead zones.

[0062] Step 3 specifically includes the following steps:

[0063] Step 3-1: When the high-voltage reactor is directly connected to the transmission line via a disconnector without passing through a circuit breaker, determine the protection operation logic of the transmission line and the busbars connected to both sides of the transmission line.

[0064] Step 3-2: When the high-voltage reactor is connected to the transmission line directly via a disconnector without going through a circuit breaker, determine the protection action logic of the offshore high-voltage reactor station.

[0065] In step 3-1, the protection operation logic for the sending line and the busbars connected to both sides of the sending line is as follows:

[0066] like Figure 8 As shown, when a fault occurs on the transmission line (point K2) from the offshore high-voltage reactor station to the offshore booster station, both the large differential protection and the small differential protection can operate quickly. The differential protection function of the large differential protection will quickly trip the switches on both sides of the transmission line;

[0067] The differential protection function in the offshore substation side's differential protection will also quickly trip the switch on the offshore substation side. Simultaneously, the offshore high-voltage reactor substation side's differential protection will send a trip signal to the "Other Protection Action Input" terminal of the offshore high-voltage reactor substation side's differential protection device within the protection range of the offshore high-voltage reactor substation to the onshore substation. Then, a remote trip signal will be sent, and after the onshore substation side's line differential protection remote trip local judgment is met, the onshore substation side switch will trip. The protection action logic is the same when a fault occurs within the range of the offshore high-voltage reactor substation to the onshore substation's outgoing line. When a fault occurs on the offshore substation's high-voltage busbar (point k1), the bus differential protection will quickly trip the switches of all branches connected to the high-voltage busbar. For a 220kV busbar, the bus differential protection will simultaneously remotely trip the onshore substation's outgoing line switch via the line differential protection. The protection action logic is the same when a fault occurs on the onshore substation's high-voltage busbar.

[0068] In step 3-2, the protection action logic of the offshore high-altitude anti-aircraft station is as follows:

[0069] like Figure 9 As shown, when a fault occurs in the T-section (k3 point) or the energy-draining high-voltage reactor (k4 point) formed by the offshore high-voltage reactor station connecting to the transmitting line, the trip signal of the T-section bus differential protection or the energy-draining high-voltage reactor electrical quantity protection will be sent to the remote transmission 1 terminal of the two line differential protections on the offshore high-voltage reactor station side (offshore high-voltage reactor station to offshore substation, offshore high-voltage reactor station to onshore substation). Then, the remote transmission 1 signal is sent to the line differential protection on the other side. The differential protection on the other side then communicates the TJR contact through the signal to trip the three phases, and at the same time, the switch failure protection is activated. When a fault occurs on the low-voltage side (k5 point) of the 6kV substation, and the high-voltage side switch fails or the pumping high-resistance non-electrical quantity protection operates, the operation signal of the switch failure protection or the pumping high-resistance non-electrical quantity protection will be sent to the remote transmission 2 terminal of the two line differential protections on the offshore high-resistance substation side (offshore high-resistance substation to offshore substation, offshore high-resistance substation to onshore substation). Then, the remote transmission 2 signal is sent to the line differential protection on the other side. The differential protection on the other side then sends a signal to the TJF contact to trip the three phases, without activating the switch failure protection.

[0070] Step 4 specifically includes the following steps:

[0071] Step 4-1: When the high-voltage shock absorber is connected to the transmission line via the circuit breaker, determine the protection configuration method for the transmission line and the busbars connected to both sides of the transmission line.

[0072] Step 4-2: When the high-voltage reactor is connected to the transmission line via the circuit breaker, determine the protection configuration method for the offshore high-voltage reactor station.

[0073] In step 4-1, the protection configuration method for the sending line and the busbars connected to both sides of the sending line is as follows:

[0074] like Figure 7 As shown, the transmitting line only needs to be equipped with small differential protection, not large differential protection. Both the line between the offshore high-voltage reactor station and the offshore substation, and the line between the offshore high-voltage reactor station and the onshore substation, require dual sets of small differential protection. The protection range of the small differential protection is from the offshore high-voltage reactor station to the substations on both sides. Each set of small differential protection needs to be equipped with differential protection, grounding and phase-to-phase distance protection, zero-sequence overcurrent protection, reclosing and overvoltage protection, and remote tripping protection. The local criteria for remote tripping protection include current change, zero negative sequence current, zero negative sequence voltage, low current, low power factor, and low active power. Both the offshore and onshore substation busbars connected to the transmitting line need to be equipped with dual bus differential protection. When the transmitting line is at a voltage level of 220kV, the bus differential protection needs to be equipped with switch failure protection. The configuration of the line's small differential protection and the bus differential protection of the substations on both sides must ensure the elimination of protection dead zones.

[0075] In step 4-2, the protection configuration method for the offshore high-altitude anti-tank station is as follows:

[0076] like Figure 7 As shown, the T-section formed by the offshore high-voltage reactor station connected to the transmission line requires dual bus differential protection. The pumping reactor needs dual electrical quantity protection, including main reactor differential protection, inter-turn protection, overcurrent protection, overload alarm, and zero-sequence overcurrent protection. It also includes pumping-side differential protection, pumping-side inter-turn protection, pumping-side winding overvoltage overcurrent protection, pumping-side switch overvoltage overcurrent protection, and pumping-side winding zero-sequence overcurrent protection. Simultaneously, the pumping reactor also needs a single set of non-electrical quantity protection. The low-voltage station transformer connected to the pumping side of the pumping reactor needs a single set of transformer protection, including longitudinal differential protection, instantaneous trip protection, and overcurrent protection. The circuit breaker connected to the high-voltage side of the station transformer needs switch failure protection. When configuring the line differential protection, T-section bus differential protection, and pumping high-voltage reactor protection, it is necessary to ensure the elimination of protection dead zones.

[0077] Step 5 specifically includes the following steps:

[0078] Step 5-1: When the high-voltage shock absorber is connected to the transmission line via the circuit breaker, determine the protection operation logic of the transmission line and the busbars connected to both sides of the transmission line.

[0079] Step 5-2: When the high-voltage reactor is connected to the transmission line via the circuit breaker, determine the protection action logic of the offshore high-voltage reactor station.

[0080] In step 5-1, the protection operation logic for the sending line and the busbars connected to both sides of the sending line is as follows:

[0081] like Figure 10 As shown, when a fault occurs on the transmission line from the offshore high-voltage reactor station to the offshore substation (point k2), the differential protection function in the small differential protection will quickly trip the switches on both the offshore substation side and the offshore high-voltage reactor station side. The protection operation logic is the same when a fault occurs within the transmission line range from the offshore high-voltage reactor station to the onshore substation. When a fault occurs on the high-voltage busbar of the offshore substation (point k1), the bus differential protection will quickly trip the switches of all branches connected to the high-voltage busbar. For a 220kV busbar, the bus differential protection will also remotely trip the switch of the opposite offshore high-voltage reactor station (closer to the offshore substation side) through the line small differential protection. The protection operation logic is the same when a fault occurs on the high-voltage busbar of the onshore substation.

[0082] In step 5-2, the protection action logic of the offshore high-altitude anti-aircraft station is as follows:

[0083] like Figure 11 As shown, when a fault occurs in the T-section (k3 point) or the energy-draining high-resistance device (k4 point) formed by the offshore high-resistance station connecting to the transmitting line, the T-section bus differential protection or the energy-draining high-resistance device electrical quantity protection will quickly trip the two switches of the offshore high-resistance station. At the same time, the trip signal of the T-section bus differential protection or the energy-draining high-resistance device electrical quantity protection will be sent to the remote transmission 1 terminal of the two line differential protections on the offshore high-resistance station side (offshore high-resistance station to offshore substation, offshore high-resistance station to onshore substation), and then the remote transmission 1 signal will be sent to the line differential protection on the other side. The line differential protection on the other side will then communicate with the TJR contact through the signal to trip the three phases, and at the same time start the switch failure protection. When a fault occurs on the low-voltage side (k5 point) of the station service transformer, the high-voltage side switch fails, or the pumping high-resistance non-electrical quantity protection operates, the switch failure protection or the pumping high-resistance non-electrical quantity protection will trip the two switches of the offshore high-resistance station. At the same time, the operation signal of the switch failure protection or the pumping high-resistance non-electrical quantity protection will be sent to the remote transmission 2 terminal of the two line differential protections on the offshore high-resistance station side (offshore high-resistance station to offshore substation, offshore high-resistance station to onshore substation), and then the remote transmission 2 signal will be sent to the line differential protection on the other side. The differential protection on the other side will then communicate with the TJF contact through the signal to trip the three phases, without activating the switch failure protection.

[0084] also, Figure 3First, it is necessary to clarify the specific wiring configuration of the high-voltage protection device (HVP) connected to the transmission line. There are two configurations: direct connection via a disconnecting switch without a circuit breaker, and connection via a circuit breaker. When the HVP is directly connected to the transmission line via a disconnecting switch, the configuration method and operating logic of the protection under this wiring configuration must be clarified. When the HVP is connected to the transmission line via a circuit breaker, the configuration method and operating logic of the protection under this wiring configuration must also be clarified.

[0085] Figure 4 In this process, the offshore wind farm's voltage is boosted to 220kV and then transmitted via submarine cable to a 220kV onshore substation, before being further boosted and connected to the 500kV AC main grid. The offshore high-voltage substation is directly connected to the middle section of the 220kV submarine cable line via a disconnecting switch, without a circuit breaker.

[0086] Figure 5 In this process, the offshore wind farm's voltage is boosted to 220kV and then transmitted via submarine cable to a 220kV onshore substation, before being further boosted and connected to the 500kV AC main grid. The offshore high-voltage substation is connected to the middle section of the 220kV submarine cable line via a circuit breaker.

[0087] Figure 6 In the transmission line, both large and small differential protection are configured. The large differential protection is a longitudinal current differential protection that can protect the entire transmission line, with a dual configuration. The lines between the offshore high-voltage reactor station and the offshore substation, and between the offshore high-voltage reactor station and the onshore substation, are equipped with dual sets of small differential protection. The protection range of the small differential protection extends from the offshore high-voltage reactor station to the substations on both sides. Both the busbars of the offshore and onshore substations connected to the transmission line are equipped with dual bus differential protection. The T-section formed by the connection of the offshore high-voltage reactor station to the transmission line is equipped with dual bus differential protection. The pumping reactor is equipped with dual electrical quantity protection and a single set of non-electrical quantity protection. The low-voltage station transformer connected to the pumping side of the pumping reactor is equipped with a single set of transformer protection. The circuit breaker connected to the high-voltage side of the low-voltage station transformer is equipped with switch failure protection.

[0088] Figure 7 In this system, the lines between the offshore high-voltage reactor station and the offshore substation, as well as the lines between the offshore high-voltage reactor station and the onshore substation, are equipped with dual sets of differential protection. The protection range of the differential protection extends from the offshore high-voltage reactor station to the substations on both sides. Both the busbars of the offshore and onshore substations connected by the transmitting lines are equipped with dual bus differential protection. The T-sections formed by the offshore high-voltage reactor connecting to the transmitting lines are equipped with dual bus differential protection. The pumping reactors are equipped with dual electrical quantity protection and a single set of non-electrical quantity protection. The low-voltage station transformers connected to the pumping side of the pumping reactors are equipped with a single set of transformer protection. The circuit breakers connected to the high-voltage side of the low-voltage station transformers are equipped with switch failure protection.

[0089] Figure 8When a fault occurs on the transmission line (point K2) from the offshore high-voltage reactor station to the offshore substation, the differential protection function of the offshore substation side differential protection will quickly trip the switch on the offshore substation side. At the same time, the offshore high-voltage reactor station side differential protection will send the trip signal to the "Other Protection Action Input" terminal of the offshore high-voltage reactor station side differential protection device within the range from the offshore high-voltage reactor station to the onshore substation. Then, a remote trip signal will be sent. After the onshore substation side line differential protection remote trip local judgment criteria are met, the onshore substation side switch will trip.

[0090] Figure 9 When a fault occurs in the T-section (k3 point) or the pumped high-voltage reactor (k4 point) formed by the connection of the pumped high-voltage reactor to the transmission line, the trip signal of the T-section bus differential protection or the pumped high-voltage reactor electrical quantity protection will be sent to the remote transmission 1 terminal of the two line differential protections on the side of the offshore high-voltage reactor station (offshore high-voltage reactor station to offshore substation, offshore high-voltage reactor station to onshore substation). Then, the remote transmission 1 signal is sent to the line differential protection on the other side. The differential protection on the other side then communicates the TJR contact through the signal to trip the three phases, and at the same time, the switch failure protection is activated. When a fault occurs on the low-voltage side (k5 point) of the 6kV substation, and the high-voltage side switch fails or the pumping high-resistance non-electrical quantity protection operates, the operation signal of the switch failure protection or the pumping high-resistance non-electrical quantity protection will be sent to the remote transmission 2 terminal of the two line differential protections on the offshore high-resistance substation side (offshore high-resistance substation to offshore substation, offshore high-resistance substation to onshore substation). Then, the remote transmission 2 signal is sent to the line differential protection on the other side. The differential protection on the other side then sends a signal to the TJF contact to trip the three phases, without activating the switch failure protection.

[0091] Figure 10 In the process, when a fault occurs in the transmission line (k2 point) from the offshore high-voltage reactor station to the offshore booster station, the differential protection function in the small differential protection will quickly trip the switches on the offshore booster station side and the offshore high-voltage reactor station side.

[0092] Figure 11When a fault occurs in the T-section (k3 point) or the pumped high-voltage reactor (k4 point) formed by the connection of the pumped high-voltage reactor to the transmission line, the T-section bus differential protection or the pumped high-voltage reactor electrical quantity protection will quickly trip the two switches of the offshore high-voltage reactor station. At the same time, the trip signal of the T-section bus differential protection or the pumped high-voltage reactor electrical quantity protection will be sent to the remote transmission 1 terminal of the two line differential protections on the offshore high-voltage reactor station side (offshore high-voltage reactor station to offshore substation, offshore high-voltage reactor station to onshore substation). Then, the remote transmission 1 signal is sent to the line differential protection on the other side. The line differential protection on the other side then communicates the TJR contact through the signal to trip the three phases, and at the same time, the switch failure protection is activated. When a fault occurs on the low-voltage side (k5 point) of the 6kV substation transformer and the high-voltage side switch fails or the pumping high-resistance non-electrical quantity protection operates, the switch failure protection or the pumping high-resistance non-electrical quantity protection will trip the two switches of the offshore high-resistance station. At the same time, the operation signal of the switch failure protection or the pumping high-resistance non-electrical quantity protection will be sent to the remote transmission 2 terminal of the two line differential protections on the offshore high-resistance station side (offshore high-resistance station to offshore substation, offshore high-resistance station to onshore substation), and then the remote transmission 2 signal will be sent to the line differential protection on the other side. The differential protection on the other side will then communicate with the TJF contact through the signal to trip the three phases without activating the switch failure protection.

[0093] In addition, refer to Figure 1 As shown, according to a second aspect of this embodiment, a storage medium is provided. The storage medium includes a stored program, wherein, when the program is executed, a processor performs any of the methods described above.

[0094] Therefore, according to this embodiment, for the connection form where the pumping reactor of an offshore high-voltage wind power station is directly connected to the transmission line via a disconnector without a circuit breaker, when the T-zone, the pumping reactor, or the station service transformer in the offshore high-voltage wind power station fails or the high-voltage side switch malfunctions, the traditional transmission line protection configuration method with parallel reactors is difficult to apply because the pumping reactor is not connected via a circuit breaker. How to achieve reliable tripping of the protection on both sides of the transmission line is a major challenge. This invention provides protection methods for pumping reactors connected to the transmission line in different ways. For the two connection forms—the pumping reactor directly connected to the transmission line via a disconnector without a circuit breaker and the pumping reactor connected to the transmission line via a circuit breaker—corresponding protection configuration methods and protection operation logic are proposed respectively, solving the problem of how the protection trips in the above scenarios. This provides a reliable technical solution for offshore wind power transmission and greatly improves the absorption capacity of new energy.

[0095] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0096] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0097] Example 2

[0098] Figure 12 A protection device 1200 for different methods of accessing the power extraction high-resistance transmission line according to this embodiment is shown. This device 1200 corresponds to the method described according to the first aspect of Embodiment 1. (See reference...) Figure 12 As shown, the device 1200 includes: a first determining module 1210, used to determine the wiring configuration of the energy extraction high-voltage reactor connected to the transmission line, wherein the energy extraction high-voltage reactor is installed in the offshore power grid system; a second determining module 1220, used to determine the protection configuration method of the offshore power grid system according to the wiring configuration; and a third determining module 1230, used to determine the protection action logic of the offshore power grid system according to the protection configuration method.

[0099] Optionally, the wiring configuration includes connection to the transmission line without a circuit breaker and connection to the transmission line with a circuit breaker. The offshore power grid system includes an offshore substation busbar, a transmission line, an offshore high-voltage reactor station, and an onshore substation busbar. The second determining module 1220 includes: a first determining submodule, used to determine a first protection configuration method for the transmission line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is connection to the transmission line without a circuit breaker; and a second determining submodule, used to determine a second protection configuration method for the offshore high-voltage reactor station.

[0100] Optionally, the first determining submodule includes: a first configuration unit for configuring dual differential protection on the transmitting line, wherein the differential protection is configured with differential protection, grounding and phase-to-phase distance protection, zero-sequence overcurrent protection, reclosing and overvoltage protection, and remote tripping protection functions, and the local criteria for remote tripping protection include current change, zero negative sequence current, zero negative sequence voltage, low current, low power factor, and low active power; and a second configuration unit for configuring protection from the offshore high-voltage reactor station to the offshore booster station and the offshore high-voltage reactor station. A dual differential protection system is configured between the transmission line and the onshore substation. The differential protection system includes differential protection, grounding and phase-to-phase distance protection, zero-sequence overcurrent protection, reclosing and overvoltage protection, and remote tripping protection. The local criteria for remote tripping protection include current change, zero negative sequence current, zero negative sequence voltage, low current, low power factor, and low active power. The third configuration unit is used to configure dual bus differential protection for the busbars connecting the transmission line to the offshore substation and the busbars connecting to the onshore substation.

[0101] Optionally, the second determining submodule includes: a fourth configuration unit for configuring dual bus differential protection for the T-section formed by the transmission line connected to the offshore high-voltage reactor station; a fifth configuration unit for configuring dual electrical quantity protection and a single set of non-electrical quantity protection for the extraction reactor, wherein the electrical quantity protection includes main reactor differential protection, inter-turn protection, overcurrent protection, overload alarm, zero-sequence overcurrent protection, extraction side differential protection, extraction side inter-turn protection, extraction side winding overvoltage overcurrent, extraction side switch overvoltage overcurrent, and extraction side winding zero-sequence overcurrent function; a sixth configuration unit for configuring a single set of transformer protection for the low-voltage station transformer connected to the extraction side of the extraction reactor of the offshore high-voltage reactor station, wherein the single set of transformer protection includes longitudinal differential protection, instantaneous trip, and overcurrent protection functions; and a seventh configuration unit for configuring switch failure protection for the circuit breaker connected to the high-voltage side of the low-voltage station transformer.

[0102] Optionally, the third determining module 1230 includes: a third determining submodule, used to determine the first protection action logic of the sending line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is to connect to the sending line without passing through a circuit breaker; and a fourth determining submodule, used to determine the second protection action logic of the offshore high-voltage anti-static station.

[0103] Optionally, the third determining submodule includes: a first protection unit, used to trip the switches on both sides of the transmission line in the event of a fault in the transmission line between the offshore high-voltage reactor station and the offshore substation, or a fault in the transmission line between the offshore high-voltage reactor station and the onshore substation, wherein the differential protection function of the large differential protection trips the switches on both sides of the transmission line, the differential protection function of the small differential protection on the offshore substation side trips the switches on both sides of the offshore substation, and the small differential protection on the offshore high-voltage reactor station side sends a trip signal to the small differential protection device on the offshore high-voltage reactor station side within the protection range of the transmission line between the offshore high-voltage reactor station and the onshore substation. The differential protection device on the offshore high-voltage protection station side within the protection range of the outgoing line from the offshore high-voltage protection station to the offshore substation sends a remote trip signal. After the remote trip local criterion of the differential protection on the onshore substation side is met, the switch on the onshore substation side is tripped. / And sends a remote trip signal. After the remote trip local criterion of the differential protection on the offshore substation side is met, the switch on the offshore substation side is tripped. The second protection unit is used to trip all switches connected to the high-voltage bus of the offshore substation / all switches connected to the high-voltage bus of the onshore substation in the event of a fault in the high-voltage bus of the offshore substation / a fault in the high-voltage bus of the onshore substation. It also remotely trips the switches of the outgoing line on the onshore substation side / the switches of the outgoing line on the offshore substation side through the differential protection of the outgoing line.

[0104] Optionally, the fourth determining submodule includes: a third protection unit, used to, in the event of a fault in the T-section / energy-extraction high-voltage reactor connected to the transmission line of the offshore high-voltage reactor station, have the trip signals of the bus differential protection / electrical quantity protection of the T-section / energy-extraction high-voltage reactor respectively input to the remote transmission 1 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and send the remote transmission 1 signal to the differential protection of the opposite line to generate a trip signal, and this trip signal simultaneously activates the switch failure protection of the opposite side; and a fourth protection unit, used to, in the event of a fault on the low-voltage side of the station service transformer, the high-voltage side switch failure / energy-extraction high-voltage reactor non-electrical quantity protection operation, have the operation signals of the switch failure protection / energy-extraction high-voltage reactor non-electrical quantity protection respectively input to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and send the remote transmission 2 signal to the differential protection of the opposite line to generate a trip signal, and this trip signal does not activate the switch failure protection of the opposite side.

[0105] Optionally, the second determining module 1220 further includes: a fifth determining submodule, used to determine the third protection configuration method for the sending line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is connected to the sending line via a circuit breaker; and a sixth determining submodule, used to determine the fourth protection configuration method for the offshore high-voltage anti-seismic station.

[0106] Optionally, the fifth determining submodule includes: an eighth configuration unit, used to configure dual differential protection for the transmission lines between the offshore high-voltage reactor station and the offshore substation, and the transmission lines between the offshore high-voltage reactor station and the onshore substation, wherein the differential protection is configured with differential protection, grounding and phase-to-phase distance protection, zero-sequence overcurrent protection, reclosing and overvoltage and remote tripping protection functions, and the local criteria for remote tripping protection include current change, zero negative sequence current, zero negative sequence voltage, low current, low power factor and low active power; and a ninth configuration unit, used to configure dual bus differential protection for the busbars of the offshore substation and the onshore substation connected to the transmission lines.

[0107] Optionally, the sixth determining submodule includes: a tenth configuration unit for configuring dual bus differential protection for the T-section formed by the transmission line connected to the offshore high-voltage reactor station; an eleventh configuration unit for configuring dual electrical quantity protection and a single set of non-electrical quantity protection for the extraction reactor, wherein the electrical quantity protection includes main reactor differential protection, inter-turn protection, overcurrent protection, overload alarm, zero-sequence overcurrent protection, extraction side differential protection, extraction side inter-turn protection, extraction side winding overvoltage overcurrent, extraction side switch overvoltage overcurrent, and extraction side winding zero-sequence overcurrent function; a twelfth configuration unit for configuring a single set of transformer protection for the low-voltage station transformer connected to the extraction side of the extraction reactor of the offshore high-voltage reactor station, wherein the single set of transformer protection includes longitudinal differential protection, instantaneous trip, and overcurrent protection functions; and a thirteenth configuration unit for configuring switch failure protection for the circuit breaker connected to the high-voltage side of the low-voltage station transformer.

[0108] Optionally, the third determining module 1230 includes: a seventh determining submodule, used to determine the third protection action logic of the sending line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is connected to the sending line via a circuit breaker; and an eighth determining submodule, used to determine the fourth protection action logic of the offshore high-voltage anti-seismic station.

[0109] Optionally, the seventh determining submodule includes: a fifth protection unit, used to quickly trip the switches on the offshore substation side and the offshore high-voltage station side / on the offshore high-voltage station side in the event of a fault in the transmission line from the offshore high-voltage station to the offshore substation / in the event of a fault in the transmission line from the offshore high-voltage station to the onshore substation; and a sixth protection unit, used to quickly trip the switches of all branches connected to the high-voltage busbar in the event of a fault in the high-voltage busbar of the offshore substation / in the event of a fault in the high-voltage busbar of the onshore substation, and remotely trip the switch of the opposite offshore high-voltage station through the differential protection of the transmission line.

[0110] Optionally, the eighth determining submodule includes: a seventh protection unit, used to quickly trip the two switches of the offshore high-voltage reactor station when a fault occurs in the T-section / energy-extraction high-voltage reactor formed by the transmission line connected to the offshore high-voltage reactor station. Simultaneously, the trip signals of the T-section's bus differential protection / energy-extraction high-voltage reactor's electrical quantity protection are respectively input to the remote transmission 1 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and the remote transmission 1 signal is sent to the differential protection of the opposite line to generate a trip signal, and this trip signal is simultaneously activated. The eighth protection unit is used to trip the two switches of the offshore high-voltage station when the high-voltage side switch fails / the energy extraction high-resistance non-electrical quantity protection operates in the event of a fault on the low-voltage side of the station service transformer. At the same time, the operation signal of the switch failure protection / energy extraction high-resistance non-electrical quantity protection is respectively sent to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-resistance station, and the remote transmission 2 signal is sent to the differential protection of the opposite line to generate a trip signal. This trip signal does not activate the switch failure protection on the opposite side.

[0111] Therefore, according to this embodiment, for the connection form where the pumping reactor of an offshore high-voltage wind power station is directly connected to the transmission line via a disconnector without a circuit breaker, when the T-zone, the pumping reactor, or the station service transformer in the offshore high-voltage wind power station fails or the high-voltage side switch malfunctions, the traditional transmission line protection configuration method with parallel reactors is difficult to apply because the pumping reactor is not connected via a circuit breaker. How to achieve reliable tripping of the protection on both sides of the transmission line is a major challenge. This invention provides protection methods for pumping reactors connected to the transmission line in different ways. For the two connection forms—the pumping reactor directly connected to the transmission line via a disconnector without a circuit breaker and the pumping reactor connected to the transmission line via a circuit breaker—corresponding protection configuration methods and protection operation logic are proposed respectively, solving the problem of how the protection trips in the above scenarios. This provides a reliable technical solution for offshore wind power transmission and greatly improves the absorption capacity of new energy.

[0112] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0113] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0114] In the several embodiments provided by this invention, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection of units or modules may be electrical or other forms.

[0115] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0116] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0117] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0118] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle 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 protection method for high-voltage transmission lines with different access methods, characterized in that, include: The wiring configuration of the high-voltage pumping reactor connected to the transmission line is determined, and the high-voltage pumping reactor is installed in the offshore power grid system; Based on the wiring configuration, determine the protection configuration method for the offshore power grid system; Based on the protection configuration method, the protection action logic of the offshore power grid system is determined; The wiring configuration includes connection to the transmitting line without a circuit breaker and connection to the transmitting line via a circuit breaker. The offshore power grid system includes an offshore substation busbar, a transmitting line, an offshore high-voltage reactor station, and an onshore substation busbar. The operation of determining the protection configuration method for the offshore power grid system based on the wiring configuration includes: In the case where the wiring configuration is to connect to the outgoing line without passing through a circuit breaker, a first protection configuration method is determined for the outgoing line, the offshore substation busbar, and the onshore substation busbar. Determine the configuration method for the second protection of the offshore high-altitude anti-tank station; The operation of determining the first protection configuration method for the transmitting line, the offshore substation busbar, and the onshore substation busbar includes: The transmitting line is equipped with dual differential protection, wherein the differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions, and the local criteria for the remote tripping protection are current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power. Dualized differential protection is configured between the offshore high-voltage reactor station and the offshore booster station, as well as between the offshore high-voltage reactor station and the onshore booster station. The differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions. The local criteria for remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power. The busbars connecting the transmission line to the offshore substation and the busbars connecting to the onshore substation are equipped with dual bus differential protection. The operation of determining the second protection configuration method for the offshore high-altitude anti-tank station includes: Configure dual bus differential protection for the T-section formed by the connection of the offshore high-voltage anti-tank station to the transmission line; The energy extraction high-resistance is configured with dual electrical quantity protection and a single set of non-electrical quantity protection, wherein the electrical quantity protection includes main reactor differential protection / inter-turn protection / overcurrent protection / overload alarm / zero-sequence overcurrent protection / energy extraction side differential protection / energy extraction side inter-turn protection / energy extraction side winding overvoltage overcurrent / energy extraction side switch overvoltage overcurrent / energy extraction side winding zero-sequence overcurrent function; A single transformer protection system is configured for the low-voltage station transformer connected to the energy extraction side of the energy extraction reactor of the offshore high-voltage station, wherein the single transformer protection system includes longitudinal differential protection / instantaneous overcurrent / overcurrent protection functions. Configure switch failure protection for the circuit breaker connected to the high-voltage side of the transformer in the low-voltage station.

2. The method according to claim 1, characterized in that, The operation of determining the protection action logic of the offshore power grid system according to the protection configuration method includes: When the wiring configuration is to connect to the outgoing line without passing through a circuit breaker, determine the first protection action logic for the outgoing line, the offshore substation busbar, and the onshore substation busbar. Determine the second protection action logic of the offshore high-altitude anti-tank station.

3. The method according to claim 2, characterized in that, The operation of determining the first protection action logic for the sending line, the offshore substation busbar, and the onshore substation busbar includes: In the event of a fault in the outgoing line between the offshore high-voltage reactor station and the offshore booster station, or a fault in the outgoing line between the offshore high-voltage reactor station and the onshore booster station, the differential protection function of the large differential protection trips the switches on both sides of the outgoing line; the differential protection function of the small differential protection on the offshore booster station side trips the switch on the offshore booster station side; the differential protection function of the small differential protection on the onshore booster station side trips the switch on the onshore booster station side; and the small differential protection on the offshore high-voltage reactor station side sends a trip signal to the offshore high-voltage reactor station. The differential protection device on the offshore high-voltage reactor side within the protection range of the transmission line from the offshore high-voltage reactor to the onshore substation will send a trip signal to the differential protection device on the offshore high-voltage reactor side within the protection range of the transmission line from the offshore high-voltage reactor to the offshore substation, and send a remote trip signal. After the remote trip local criterion of the differential protection on the onshore substation side is met, the switch on the onshore substation side will trip. In the event of a fault in the high-voltage busbar of the offshore substation or the high-voltage busbar of the onshore substation, the bus differential protection trips all switches connected to the high-voltage busbar of the offshore substation or the high-voltage busbar of the onshore substation, and remotely trips the switches of the outgoing line on the onshore substation side or the outgoing line on the offshore substation side via the large differential protection of the outgoing line.

4. The method according to claim 2, characterized in that, The operations for determining the second protection action logic of the offshore anti-tank station include: In the event of a fault in the T-section / energy extraction high-resistance device connected to the transmitting line at the marine high-resistance station, the trip signal of the bus differential protection of the T-section / the electrical quantity protection of the energy extraction high-resistance device is respectively input to the remote transmission 1 terminal of the small differential protection of the two lines at the marine high-resistance station, and the remote transmission 1 signal is sent to the small differential protection of the opposite line to generate a trip signal, and this trip signal simultaneously activates the switch failure protection on the opposite side; In the event of a fault on the low-voltage side of the station service transformer, a malfunction of the high-voltage side switch, or the activation of the non-electrical quantity protection of the energy extraction high-resistance transformer, the activation signals of the switch malfunction protection and the non-electrical quantity protection of the energy extraction high-resistance transformer are respectively input to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-resistance transformer station, and the remote transmission 2 signal is sent to the differential protection of the opposite line to generate a trip signal, and this trip signal does not activate the switch malfunction protection on the opposite side.

5. The method according to claim 1, characterized in that, The operation of determining the protection configuration method for the offshore power grid system based on the wiring configuration further includes: In the case where the wiring configuration is connected to the outgoing line via a circuit breaker, a third protection configuration method is determined for the outgoing line, the offshore substation busbar, and the onshore substation busbar. The fourth protection configuration method for the aforementioned high-altitude anti-tank station was determined.

6. The method according to claim 5, characterized in that, The operation of determining the third protection configuration method for the transmitting line, the offshore substation busbar, and the onshore substation busbar includes: The transmission lines between the offshore high-voltage reactor station and the offshore substation, and the transmission lines between the offshore high-voltage reactor station and the onshore substation are equipped with dual differential protection. The differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions. The local criteria for remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power. The busbars of the offshore substations connected to the transmission line and the onshore substations are equipped with dual bus differential protection.

7. The method according to claim 6, characterized in that, The operation of determining the fourth protection configuration method for the aforementioned high-altitude anti-tank station includes: Configure dual bus differential protection for the T-section formed by the connection of the offshore high-voltage station to the transmission line; The energy extraction high-resistance is configured with dual electrical quantity protection and a single set of non-electrical quantity protection, wherein the electrical quantity protection includes main reactor differential protection / inter-turn protection / overcurrent protection / overload alarm / zero-sequence overcurrent protection / energy extraction side differential protection / energy extraction side inter-turn protection / energy extraction side winding overvoltage overcurrent / energy extraction side switch overvoltage overcurrent / energy extraction side winding zero-sequence overcurrent function; A single transformer protection system is configured for the low-voltage station transformer connected to the pumping side of the pumping reactor of the offshore high-voltage station, wherein the single transformer protection system includes longitudinal differential protection / instantaneous overcurrent protection functions. Configure switch failure protection for the circuit breaker connected to the high-voltage side of the transformer in the low-voltage station.

8. The method according to claim 7, characterized in that, The operation of determining the protection action logic of the offshore power grid system according to the protection configuration method includes: When the wiring configuration is to connect to the outgoing line via a circuit breaker, the third protection action logic for the outgoing line, the offshore substation busbar, and the onshore substation busbar is determined. Determine the fourth protection action logic of the aforementioned high-altitude anti-tank station.

9. The method according to claim 8, characterized in that, The operation of determining the third protection action logic for the sending line, the offshore substation busbar, and the onshore substation busbar includes: In the event of a fault in the transmission line from the offshore high-voltage reactor station to the offshore substation, or a fault in the transmission line from the offshore high-voltage reactor station to the onshore substation, the differential protection function in the small differential protection shall quickly trip the switches on the offshore substation side and the offshore high-voltage reactor station side; In the event of a fault in the high-voltage busbar of the offshore substation or the high-voltage busbar of the onshore substation, the bus differential protection quickly trips the switches of all branches connected to the high-voltage busbar, and remotely trips the switch of the opposite offshore high-voltage station via the small differential protection of the sending line.

10. The method according to claim 8, characterized in that, The operations for determining the fourth protection action logic of the offshore high-altitude anti-tank station include: When a fault occurs in the T-interval formed by the offshore high-voltage reactor station and the outgoing line, the electrical quantity protection of the bus differential protection / electrical quantity protection of the T-interval quickly trips the two switches of the offshore high-voltage reactor station. At the same time, the trip signals of the bus differential protection / electrical quantity protection of the T-interval are respectively input to the remote transmission 1 terminal of the small differential protection of the two lines of the offshore high-voltage reactor station, and the remote transmission 1 signal is sent to the small differential protection of the opposite line to generate a trip signal. This trip signal also activates the switch failure protection on the opposite side. In the event of a fault on the low-voltage side of the station service transformer, a switch failure on the high-voltage side, or the operation of the energy extraction high-resistance non-electrical quantity protection, the switch failure protection / the energy extraction high-resistance non-electrical quantity protection trips the two switches of the offshore high-resistance station. Simultaneously, the operation signals of the switch failure protection / the energy extraction high-resistance non-electrical quantity protection are respectively input to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-resistance station, and the remote transmission 2 signal is sent to the differential protection of the opposite line to generate a trip signal. This trip signal does not activate the switch failure protection on the opposite side.

11. A computer-readable storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, the method described in any one of claims 1 to 10 is performed by a processor.

12. A protection system for high-voltage transmission lines with different access methods, characterized in that, include: The first determining module is used to determine the wiring configuration of the high-voltage pumping reactor connected to the transmission line, wherein the high-voltage pumping reactor is installed in the offshore power grid system; The second determining module is used to determine the protection configuration method of the offshore power grid system based on the wiring configuration. The third determining module is used to determine the protection action logic of the offshore power grid system according to the protection configuration method. The wiring configuration includes connection to the transmitting line without a circuit breaker and connection to the transmitting line via a circuit breaker. The offshore power grid system includes an offshore substation busbar, a transmitting line, an offshore high-voltage reactor station, and an onshore substation busbar. The second determining module includes: The first determining submodule is used to determine the first protection configuration method for the transmitting line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is to connect to the transmitting line without passing through a circuit breaker. The second determining submodule is used to determine the second protection configuration method of the offshore high-level anti-aircraft station; The first determined submodule includes: The first configuration unit is used to configure a dual differential protection on the transmission line, wherein the differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions, and the local criteria for the remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power. The second configuration unit is used to configure dual differential protection between the offshore high-voltage reactor station and the offshore substation, and between the offshore high-voltage reactor station and the onshore substation. The differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions. The local criteria for remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power. The third configuration unit is used to configure dual bus differential protection for the busbar connecting the transmission line to the offshore substation and the busbar connecting the onshore substation. The second determination submodule includes: The fourth configuration unit is used to configure dual bus differential protection for the T-section formed by the connection of the offshore high-voltage anti-tank station to the transmission line; The fifth configuration unit is used to configure dual electrical quantity protection and a single set of non-electrical quantity protection for the energy extraction high reactor. The electrical quantity protection includes main reactor differential protection / inter-turn protection / overcurrent protection / overload alarm / zero-sequence overcurrent protection / energy extraction side differential protection / energy extraction side inter-turn protection / energy extraction side winding overvoltage overcurrent / energy extraction side switch overvoltage overcurrent / energy extraction side winding zero-sequence overcurrent function. The sixth configuration unit is used to configure a single set of transformer protection for the low-voltage station transformer connected to the pumping side of the pumping reactor of the offshore high-voltage station, wherein the single set of transformer protection includes longitudinal differential protection / instantaneous overcurrent protection functions. The seventh configuration unit is used to configure switch failure protection for the circuit breaker connected to the high-voltage side of the low-voltage station transformer.

13. The system according to claim 12, characterized in that, The third determining module includes: The third determining submodule is used to determine the first protection action logic of the transmitting line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is to connect to the transmitting line without passing through a circuit breaker. The fourth determination submodule is used to determine the second protection action logic of the offshore high-altitude anti-aircraft station.

14. The system according to claim 13, characterized in that, The third determination submodule includes: The first protection unit is configured to, in the event of a fault in the outgoing line between the offshore high-voltage reactor station and the offshore substation, or a fault in the outgoing line between the offshore high-voltage reactor station and the onshore substation, cause the differential protection function of the large differential protection to trip the switches on both sides of the outgoing line; the differential protection function of the small differential protection on the offshore substation side to trip the switch on the offshore substation side; and the differential protection function of the small differential protection on the onshore substation side to trip the switch on the onshore substation side. The small differential protection on the offshore high-voltage reactor station side will then send a trip signal to the relevant circuit breaker. The differential protection device on the offshore high-voltage reactor side within the protection range of the transmission line from the offshore high-voltage reactor station to the onshore substation will send a trip signal to the differential protection device on the offshore high-voltage reactor station side within the protection range of the transmission line from the offshore high-voltage reactor station to the offshore substation, and send a remote trip signal. After the remote trip local criterion of the differential protection on the onshore substation side is met, the switch on the onshore substation side will be tripped. The second protection unit is used to trip all switches connected to the high-voltage busbar of the offshore substation / all switches connected to the high-voltage busbar of the onshore substation in the event of a fault in the high-voltage busbar of the offshore substation / the high-voltage busbar of the onshore substation, and remotely trip the switches of the outgoing line on the onshore substation side / the outgoing line on the offshore substation side through the large differential protection of the outgoing line.

15. The system according to claim 13, characterized in that, The fourth sub-module is determined, including: The third protection unit is used to, in the event of a fault in the T-section / energy-extraction high-resistance device connected to the transmitting line at the marine high-resistance station, have the trip signal of the bus differential protection of the T-section / the electrical quantity protection of the energy-extraction high-resistance device respectively input into the remote transmission 1 terminal of the small differential protection of the two lines at the marine high-resistance station, and send the remote transmission 1 signal to the small differential protection of the opposite line to generate a trip signal, and this trip signal simultaneously activates the switch failure protection on the opposite side; The fourth protection unit is used to, in the event of a fault on the low-voltage side of the station transformer, a fault on the high-voltage side switch, or the operation of the non-electrical quantity protection of the pumping high-voltage reactor, respectively input the operation signals of the switch failure protection / the non-electrical quantity protection of the pumping high-voltage reactor into the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-voltage reactor station, and send the remote transmission 2 signal to the differential protection of the opposite line to generate a trip signal, and this trip signal does not activate the switch failure protection on the opposite side.

16. The system according to claim 12, characterized in that, The second determining module also includes: The fifth determining submodule is used to determine the third protection configuration method for the transmission line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is connected to the transmission line via a circuit breaker. The sixth determining submodule is used to determine the fourth protection configuration method of the offshore high-altitude anti-aircraft station.

17. The system according to claim 16, characterized in that, The fifth determination submodule includes: The eighth configuration unit is used to configure dual differential protection for the transmission lines between the offshore high-voltage reactor station and the offshore substation, and the transmission lines between the offshore high-voltage reactor station and the onshore substation. The differential protection is configured with differential protection / grounding and phase-to-phase distance protection / zero-sequence overcurrent protection / reclosing and overvoltage / remote tripping protection functions. The local criteria for the remote tripping protection include current change / zero negative sequence current / zero negative sequence voltage / low current / low power factor / low active power. The ninth configuration unit is used to configure dual bus differential protection for the offshore substation busbar and the onshore substation busbar connected to the transmitting line.

18. The system according to claim 17, characterized in that, The sixth submodule is defined, including: The tenth configuration unit is used to configure dual bus differential protection for the T-section formed by the connection of the offshore high-voltage anti-tank station to the transmission line; The eleventh configuration unit is used to configure dual electrical quantity protection and a single set of non-electrical quantity protection for the energy extraction high reactor. The electrical quantity protection includes main reactor differential protection / inter-turn protection / overcurrent protection / overload alarm / zero-sequence overcurrent protection / energy extraction side differential protection / energy extraction side inter-turn protection / energy extraction side winding overvoltage overcurrent / energy extraction side switch overvoltage overcurrent / energy extraction side winding zero-sequence overcurrent function. The twelfth configuration unit is used to configure a single transformer protection for the low-voltage station transformer connected to the pumping side of the pumping reactor of the offshore high-voltage station, wherein the single transformer protection includes longitudinal differential protection / instantaneous overcurrent protection functions. The thirteenth configuration unit is used to configure switch failure protection for the circuit breaker connected to the high-voltage side of the low-voltage station transformer.

19. The system according to claim 18, characterized in that, The third determining module includes: The seventh determination submodule is used to determine the third protection action logic of the transmission line, the offshore substation busbar, and the onshore substation busbar when the wiring configuration is connected to the transmission line via a circuit breaker. The eighth determination submodule is used to determine the fourth protection action logic of the offshore high-altitude anti-aircraft station.

20. The system according to claim 19, characterized in that, The seventh submodule is defined, including: The fifth protection unit is used to, in the event of a fault in the transmission line from the offshore high-voltage reactor station to the offshore substation, or a fault in the transmission line from the offshore high-voltage reactor station to the onshore substation, rapidly trip the switches on the offshore substation side and the offshore high-voltage reactor station side using the differential protection function in the small differential protection; The sixth protection unit is used to, in the event of a fault in the high-voltage busbar of the offshore substation or the high-voltage busbar of the onshore substation, rapidly trip the switches of all branches connected to the high-voltage busbar, and remotely trip the switch of the opposite offshore high-voltage station via the small differential protection of the sending line.

21. The system according to claim 19, characterized in that, The eighth determination submodule includes: The seventh protection unit is used to quickly trip the two switches of the offshore high-voltage reactor station when a fault occurs in the T-section formed by the transmission line connected to the offshore high-voltage reactor station / the energy extraction high-voltage reactor. At the same time, the trip signals of the bus differential protection / the energy extraction high-voltage reactor of the T-section are respectively input to the remote transmission 1 terminal of the small differential protection of the two lines of the offshore high-voltage reactor station, and the remote transmission 1 signal is sent to the small differential protection of the opposite line to generate a trip signal. This trip signal also activates the switch failure protection on the opposite side. The eighth protection unit is used to trip the two switches of the offshore high-voltage station in the event of a fault on the low-voltage side of the station transformer, a failure of the high-voltage side switch, or the operation of the energy extraction high-voltage reactor non-electrical quantity protection. At the same time, the operation signals of the switch failure protection and the energy extraction high-voltage reactor non-electrical quantity protection are respectively input to the remote transmission 2 terminal of the differential protection of the two lines of the offshore high-voltage station, and the remote transmission 2 signal is sent to the differential protection of the opposite line to generate a trip signal. This trip signal does not activate the switch failure protection on the opposite side.

Images