A commutation transformer protection system and method without grid-side switch in a station

Abstract

The present application relates to a converter transformer protection system for a station without grid-side switches, a substation, and a converter station electrically connected to the substation; the substation includes a transmission line and a first line protection device disposed on the transmission line; the converter station includes a transformer, and a second line protection device, a converter transformer quantity protection device, and a converter transformer non-quantity protection device, each electrically connected to the transformer. Compared to the prior art, the converter transformer protection system for a station without grid-side switches of the present invention solves the problem of excessively long tripping circuit cables, which are susceptible to malfunctioning protection due to the distributed capacitance of the long cables, thus causing DC outages, thus meeting practical application requirements.

Description

Technical Field

[0001] The present application relates to the technical field of power grid operation, and in particular to a commutation transformer protection system and method for a non-grid-side switch within a station. Background Art

[0002] HVDC converter stations are HVDC system facilities that function as rectifiers, inverters, or both, and are the foundation of DC power transmission. They are crucial components of power operations and play a vital role in promoting the efficient operation of power operations, rationalizing the design and construction of HVDC converter stations, promoting the smooth operation of power engineering projects, and ensuring the sustainable development of the power industry.

[0003] Back-to-back converter stations, a specialized form of HVDC transmission, can be used for asynchronous DC interconnection, addressing grid safety and stability issues caused by excessive short-circuit currents and DC commutation failures. Since back-to-back converter stations are often built at load centers, land is extremely scarce. To conserve land and investment, switches can be omitted on the grid side of the converter transformers, with the converter transformer leads connected directly to the 500kV string of the adjacent AC station. However, with this wiring arrangement, if the converter transformer protection is configured using direct cable tripping, the long tripping loop cable can easily cause malfunction of the protection due to the distributed capacitance of the long cable, leading to a DC outage. Summary of the Invention

[0004] Based on this, it is necessary to provide a converter transformer protection system and method for the above technical problems, which can solve the problem that the existing tripping circuit cable is too long, which is easily affected by the distributed capacitance of the long cable and causes false protection, thereby causing DC outage and the lack of grid-side switches in the station.

[0005] An embodiment of the present invention provides a converter transformer protection system for a station without a grid-side switch, the system comprising: a substation and a converter station electrically connected to the substation; the substation comprising a transmission line and a first line protection device arranged on the transmission line; the converter station comprising a transformer, and a second line protection device, a converter transformer quantity protection device and a converter transformer non-quantity protection device respectively electrically connected to the transformer.

[0006] Furthermore, the transmission line includes a transmission line, and a middle switch current detection point, a circuit breaker, a converter station flexible DC transformer incoming line terminal, a side circuit breaker and a side switch current detection point arranged on the transmission line.

[0007] Furthermore, the first line protection device includes a first controller, and a first current acquisition module, a first output trip module and a first remote trip module respectively electrically connected to the first controller; wherein, the acquisition end of the first current acquisition module is respectively electrically connected to the middle switch current detection point and the side switch current detection point, the output end of the first output trip module is respectively electrically connected to the circuit breaker and the side circuit breaker, and the first remote trip module performs remote communication with the second line protection device.

[0008] Furthermore, the converter station also includes a converter valve side circuit breaker, one end of the transformer is electrically connected to the converter station flexible DC transformer incoming line end of the transmission line, and the other end of the transformer is electrically connected to the converter valve side circuit breaker.

[0009] Furthermore, a head-end bushing current detection point is provided on the grid-side head-end bushing of the transformer, a tail-end bushing current detection point is provided on the grid-side tail-end bushing of the transformer, a neutral point current detection point is provided at the neutral point of the transformer, and a valve-side bushing current detection point is provided on the valve-side bushing of the transformer.

[0010] Furthermore, the second line protection device includes a second controller, and a second current acquisition module, a second output trip module and a second remote trip module electrically connected to the second controller respectively; wherein, the acquisition end of the second current acquisition module is electrically connected to the head-end bushing current detection point, the output end of the second output trip module is electrically connected to the converter valve side circuit breaker, and the second remote trip module performs remote communication with the first line protection device.

[0011] Furthermore, the converter transformer current protection device includes a third controller, and a third current acquisition module and a third output tripping module respectively electrically connected to the third controller; wherein, the acquisition end of the third current acquisition module is respectively electrically connected to the head-end bushing current detection point, the tail-end bushing current detection point and the neutral point current detection point, and the output end of the third output tripping module is respectively electrically connected to the AC station side switch and the converter transformer valve side circuit breaker.

[0012] Furthermore, the converter transformer non-electrical quantity protection device includes a fourth controller, and a non-electrical quantity collection module and a fourth output tripping module electrically connected to the fourth controller respectively; wherein, the non-electrical quantity collection module is used to collect the main oil temperature and gas information of the transformer, and the output end of the fourth output tripping module is electrically connected to the AC station side switch and the converter transformer valve side circuit breaker respectively.

[0013] Furthermore, the converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device each include an optical fiber transmission module, and the substation includes an interface device connected to the two optical fiber transmission modules respectively; wherein, the interface device includes an optical fiber receiving module and a conventional outlet module connected to the optical fiber receiving module, and the conventional outlet module is used to connect to the circuit breaker protection operation box that controls the working status of the circuit breaker and the side circuit breaker.

[0014] Another embodiment of the present invention provides a method for protecting a commutating transformer without a grid-side switch within a station, which is characterized in that it is applicable to the above-mentioned commutating transformer protection system without a grid-side switch within a station, and the method includes the following steps:

[0015] A first line protection device is established on a transmission line of a substation, wherein the first line protection device controls the working state of each circuit breaker on the transmission circuit according to a detection current of each detection point on the transmission line;

[0016] A second line protection device, a converter transformer quantity protection device, and a converter transformer non-quantity protection device are established on the transformer line of the converter station. The second line protection device controls the operating state of the converter transformer valve-side circuit breaker according to the transformer head-end bushing current. The converter transformer quantity protection device controls the operating state of the AC station-side switch and the converter transformer valve-side circuit breaker according to the transformer head-end bushing current, tail-end bushing current, and neutral point current. The converter transformer non-quantity protection device controls the operating state of the AC station-side switch and the converter transformer valve-side circuit breaker according to the transformer body oil temperature and gas information flow.

[0017] Among them, the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device are also used to simultaneously send a trip signal to the interface device of the substation through the optical fiber transmission module. The interface device instantly starts the trip command when receiving the same trip signals from the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device, delays the alarm when receiving different trip signals from the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device, and delays the start of the trip command when only receiving the trip signal from the converter transformer electric quantity protection device or the converter transformer non-electric quantity protection device.

[0018] Another embodiment of the present invention further proposes a computer-readable storage medium, which includes a stored computer program; wherein, when the computer program is running, it controls the device where the computer-readable storage medium is located to perform the all-optical microwave electric field near-field imaging method as described above.

[0019] Another embodiment of the present invention also proposes an electric power device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor implements the all-optical microwave electric field near-field imaging method as described above when executing the computer program.

[0020] The above-mentioned converter transformer protection system for in-station non-grid-side switches comprises: a substation and a converter station electrically connected to the substation; the substation including a transmission line and a first line protection device disposed on the transmission line; and the converter station including a transformer, a second line protection device, a converter transformer quantity protection device, and a converter transformer non-quantity protection device, each electrically connected to the transformer. Compared to the prior art, the present invention's converter transformer protection system for in-station non-grid-side switches solves the existing problem of excessively long tripping circuit cables, which can easily cause protection malfunctions due to the distributed capacitance of the long cables, thus resulting in DC outages. This system meets practical application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A structural block diagram of a commutation transformer protection system for a station without a grid-side switch provided by an embodiment of the present invention;

[0022] Figure 2 A schematic flow chart of an all-optical microwave electric field near-field imaging method provided by an embodiment of the present invention;

[0023] Figure 3 Schematic diagram of the energy level structure of the all-optical microwave electric field near-field imaging implementation process provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this technical field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] It should be noted that the step numbers in this article are only for the convenience of explaining the specific embodiment and do not limit the order in which the steps are executed. The method provided in this embodiment can be executed by a related server, and the following description will take the server as the execution subject as an example.

[0026] like Figures 1 to 2 As shown, an embodiment of the present invention provides a converter transformer protection system without a grid-side switch in a station, and the system includes: a substation and a converter station electrically connected to the substation.

[0027] Specifically, the substation includes a transmission line and a first line protection device provided on the transmission line. The transmission line includes a transmission line, and a middle switch current detection point, a circuit breaker, a converter station flexible DC transformer incoming line terminal, a side circuit breaker, and a side switch current detection point provided on the transmission line. The transmission line is a 500KV transmission line, and the middle switch current detection point, the circuit breaker, the converter station flexible DC transformer incoming line terminal, the side circuit breaker, and the side switch current detection point are provided on the transmission line in sequence from top to bottom, and the middle switch current detection point is linked to the circuit breaker, and the side circuit breaker is linked to the side switch current detection point. The converter station flexible DC transformer incoming line terminal is used to connect to the transformer in the converter station.

[0028] Furthermore, the first line protection device includes a first controller, and a first current acquisition module, a first output tripping module and a first remote tripping module electrically connected to the first controller respectively.

[0029] The acquisition terminal of the first current acquisition module is electrically connected to the current detection point of the middle switch and the current detection point of the side switch, respectively; the output terminal of the first output trip module is electrically connected to the circuit breaker and the side circuit breaker, respectively; and the first remote trip module communicates remotely with the second line protection device. Specifically, the first current acquisition module is configured to acquire currents at the current detection points of the middle switch and the side switch on the transmission line in real time and transmit the acquired current information to the first controller. Based on the received current information, the first controller issues a circuit breaker trip command to the circuit breaker and a side circuit breaker trip command to the side circuit breaker via the first trip output module. The first controller is also capable of communicating with the second line protection device via the first remote trip module.

[0030] Specifically, the converter station includes a transformer, and a second line protection device, a converter transformer quantity protection device, a converter transformer non-quantity protection device, and a converter transformer valve-side circuit breaker, each electrically connected to the transformer. One end of the transformer is electrically connected to the flexible DC transformer input terminal of the converter station on the transmission line, and the other end of the transformer is electrically connected to the converter transformer valve-side circuit breaker. The transformer's grid-side head-end bushing is provided with a head-end bushing current detection point, the transformer's grid-side tail-end bushing is provided with a tail-end bushing current detection point, the transformer's neutral point is provided with a neutral point current detection point, and the transformer's valve-side bushing is provided with a valve-side bushing current detection point.

[0031] Furthermore, the second line protection device includes a second controller, and a second current acquisition module, a second output tripping module and a second remote tripping module electrically connected to the second controller respectively.

[0032] The acquisition end of the second current acquisition module is electrically connected to the head-end bushing current detection point, the output end of the second output trip module is electrically connected to the converter valve-side circuit breaker, and the second remote trip module communicates remotely with the first line protection device. Specifically, the second current acquisition module is configured to acquire the current at the head-end bushing current detection point of the transformer in real time and transmit the acquired current information to the second controller. The second controller, based on the received current information (e.g., if the current is greater than a preset value), issues a trip command to the converter valve-side circuit breaker via the second trip output module. Furthermore, the second controller is capable of communicating with the first remote trip module in the first line protection device via the second remote trip module.

[0033] Furthermore, the commutation and transformation power protection device includes a third controller, and a third current acquisition module and a third output tripping module electrically connected to the third controller respectively.

[0034] The collection end of the third current acquisition module is electrically connected to the head-end bushing current detection point, the tail-end bushing current detection point, and the neutral point current detection point, respectively. The output end of the third output trip module is electrically connected to the AC station side switch and the converter transformer valve-side circuit breaker, respectively. Specifically, the third current acquisition module is configured to collect currents at the transformer head-end bushing current detection point, the tail-end bushing current detection point, and the neutral point current detection point in real time, and transmit the collected current information to the third controller. Based on the received current information, the third controller issues a trip command to the converter transformer valve-side circuit breaker and a trip command to the connected AC station side switch (a side switch and a neutral switch are provided on the AC station's transmission line) via the third trip output module. The head-end bushing current detection point is linked to the converter transformer valve-side circuit breaker, the tail-end bushing current detection point is linked to the side switch on the AC station's transmission line, and the neutral point current detection point is linked to the neutral switch on the AC station's transmission line.

[0035] Furthermore, the converter transformer non-electrical quantity protection device includes a fourth controller, and a non-electrical quantity collection module and a fourth output tripping module electrically connected to the fourth controller respectively.

[0036] The non-electrical quantity collection module is used to collect the transformer's oil temperature and gas information, and the output end of the fourth output trip module is electrically connected to the AC station's side and middle switches, as well as the converter transformer valve-side circuit breaker. Specifically, the non-electrical quantity collection module is used to collect the transformer's oil temperature and gas information in real time and transmit the collected transformer's oil temperature and gas information to the fourth controller. Based on the received oil temperature and gas information, the fourth controller issues a circuit breaker trip instruction to the circuit breaker, a side breaker trip instruction to the side circuit breaker, a converter transformer valve-side circuit breaker trip instruction to the converter transformer valve-side circuit breaker, and a side and middle switch trip instruction to the connected AC station (where the AC station's transmission line is provided with a side switch and middle switch).

[0037] It should also be noted that the converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device each include a fiber optic transmission module, and the substation includes an interface device connected to each of the two fiber optic transmission modules. The interface device includes a fiber optic receiving module and a conventional output module connected to the fiber optic receiving module. The conventional output module is used to connect to a circuit breaker protection operation box that controls the operating status of circuit breakers and side circuit breakers. The converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device are configured to simultaneously send trip signals to the substation interface device via the fiber optic transmission module. The interface device instantaneously initiates a trip command upon receiving the same trip signals from the converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device; delays an alarm upon receiving different trip signals from the converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device; and delays initiating a trip command upon receiving only a trip signal from the converter transformer electrical quantity protection device or the converter transformer non-electrical quantity protection device.

[0038] Specifically, since line protection is already deployed on both sides of the 500kV substation and converter station, a remote trip module between the two line protections can be considered to transmit trip commands for the DC control protection. However, since the converter transformer protection needs to transmit both energy-related and non-energy-related trip commands, and the line protection remote trip module only has two command inputs, these two inputs must be separated to transmit these two types of commands independently. To prevent accidental inputs, the interface device corresponding to the fiber optic transmission module instantly initiates remote tripping when it receives both remote trip input 1 and remote trip input 2. If the device receives only remote trip input 1 or remote trip input 2, it initiates remote tripping with a 30ms delay. If remote trip input 1 and remote trip input 2 are inconsistent, a delayed alarm is issued. This solution requires two commands on the line protection remote transmission channel—one for energy-related tripping and one for non-energy-related tripping—so two trip commands are generally not initiated simultaneously. The converter station control and protection device can adapt to multi-mode optical ports. Two armored multi-mode optical cables are laid between the converter station and the substation. The converter transformer protection tripping contacts use optical signal contacts. A dedicated optical fiber core is used to transmit the tripping signal to the 500kV substation, where it is converted into an electrical contact to jump the line switch.

[0039] The beneficial effects of the technical solution of the present invention are as follows:

[0040] The incoming line of the converter transformer can be connected to the nearby AC station. The AC field that has been built nearby can be used as the incoming line switch of the converter transformer, saving the floor space and construction cost of the converter station, avoiding false protection caused by the long distance of the tripping cable, and improving the reliability of the system.

[0041] Line protection is configured between the converter station and the nearby AC station, and the two stations achieve electrical decoupling of the secondary circuits. They can be operated and maintained as two stations, reducing operation and maintenance costs.

[0042] It reduces the number of long cables in the current collection and tripping circuits of the converter transformer protection, saving cable investment.

[0043] The aforementioned converter transformer protection system for in-station, non-grid-side switches comprises: a substation and a converter station electrically connected to the substation; the substation including a transmission line and a first line protection device disposed on the transmission line; and the converter station including a transformer, a second line protection device, a converter transformer quantity protection device, and a converter transformer non-quantity protection device, each electrically connected to the transformer. Compared to the prior art, the present invention's converter transformer protection system for in-station, non-grid-side switches solves the existing problem of excessively long tripping circuit cables, which can easily cause malfunctioning of protection due to the distributed capacitance of the long cables, leading to DC outages. This addresses practical application requirements.

[0044] See also Figure 3The present invention also provides a method for protecting a commutation transformer without a grid-side switch in a station, which is applicable to the above-mentioned commutation transformer protection system without a grid-side switch in a station. The method includes steps S11 to S12:

[0045] Step S11 : creating a first line protection device on a transmission line of a substation, wherein the first line protection device controls the working state of each circuit breaker on the transmission circuit according to the detection current of each detection point on the transmission line.

[0046] Step S12: Create a second line protection device, a converter transformer quantity protection device, and a converter transformer non-quantity protection device on the transformer line of the converter station. The second line protection device controls the working state of the converter transformer valve-side circuit breaker according to the head-end bushing current of the transformer. The converter transformer quantity protection device controls the working state of the AC station-side switch and the converter transformer valve-side circuit breaker according to the head-end bushing current, tail-end bushing current, and neutral point current of the transformer. The converter transformer non-quantity protection device controls the working state of the AC station-side switch and the converter transformer valve-side circuit breaker according to the transformer body oil temperature and gas information flow.

[0047] Among them, the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device are also used to simultaneously send a trip signal to the interface device of the substation through the optical fiber transmission module. The interface device instantly starts the trip command when receiving the same trip signals from the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device, delays the alarm when receiving different trip signals from the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device, and delays the start of the trip command when only receiving the trip signal from the converter transformer electric quantity protection device or the converter transformer non-electric quantity protection device.

[0048] It should be understood that, although the various steps in the above flow chart are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the above flow chart may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0049] The all-optical microwave electric field near-field imaging method provided by the embodiment of the present invention first creates a first line protection device on the transmission line of the substation, and the first line protection device controls the working state of each circuit breaker on the transmission circuit according to the detection current of each detection point on the transmission line; creates a second line protection device, a converter transformer quantity protection device and a converter transformer non-quantity protection device on the transformer line of the converter station, and the second line protection device controls the working state of the converter transformer valve side circuit breaker according to the head end bushing current of the transformer, and the converter transformer quantity protection device controls the working state of the switch on the AC station side and the converter transformer valve side circuit breaker according to the head end bushing current, the tail end bushing current and the neutral point current of the transformer. The converter transformer non-electrical quantity protection device controls the operating status of the AC station-side switches and converter transformer valve-side circuit breakers based on the transformer's oil temperature and gas flow information. The converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device are also configured to simultaneously send a trip signal to the substation interface device via an optical fiber transmission module. The interface device instantaneously initiates a trip command upon receiving identical trip signals from the converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device; issues a delayed alarm upon receiving different trip signals from the converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device; and delays initiating a trip command upon receiving only a trip signal from the converter transformer electrical quantity protection device or the converter transformer non-electrical quantity protection device. Compared to the prior art, the converter transformer protection system of the present invention, which does not distribute grid-side switches within the station, solves the problem of excessively long trip circuit cables, which are easily affected by the distributed capacitance of the long cables and thus cause malfunctioning of the protection, thereby resulting in DC outages. This meets practical application requirements.

[0050] An embodiment of the present invention also provides a computer-readable storage medium, which includes a stored computer program; wherein, when the computer program is run, it controls the device where the computer-readable storage medium is located to perform the all-optical microwave electric field near-field imaging method as described above.

[0051] An embodiment of the present invention also provides an electric power device, which includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the all-optical microwave electric field near-field imaging method as described above.

[0052] Preferably, the computer program can be divided into one or more modules / units (e.g., computer program 1, computer program 2, etc.), which are stored in the memory and executed by the processor to implement the present invention. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program in the power device.

[0053] The processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor, or the processor can be any conventional processor. The processor is the control center of the power equipment, and uses various interfaces and lines to connect the various parts of the power equipment.

[0054] The memory mainly includes a program storage area and a data storage area, wherein the program storage area can store an operating system, an application program required for at least one function, etc., and the data storage area can store related data, etc. In addition, the memory can be a high-speed random access memory, or a non-volatile memory, such as a plug-in hard disk, a smart memory card (SmartMedia Card, SMC), a secure digital (Secure Digital, SD) card, and a flash card, etc., or the memory can also be other volatile solid-state storage devices.

[0055] It should be noted that the above-mentioned power equipment may include, but is not limited to, a processor and a memory. Those skilled in the art will understand that it may also include more or fewer components, or a combination of certain components, or different components.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for protecting a commutation transformer without a grid-side switch in a station, characterized in that: The method is applicable to the above-mentioned converter transformer protection system without grid-side switches in the station, and includes the following steps: A first line protection device is established on a transmission line of a substation, wherein the first line protection device controls the operating state of each circuit breaker on the transmission line according to the detection current of each detection point on the transmission line; the transmission line includes a transmission line, and a middle switch current detection point, a circuit breaker, a flexible direct current transformer incoming line terminal of a converter station, a side circuit breaker, and a side switch current detection point provided on the transmission line; A second line protection device, a converter transformer quantity protection device, and a converter transformer non-quantity protection device are established on the transformer line of the converter station. The second line protection device controls the operating state of the converter transformer valve-side circuit breaker according to the transformer head-end bushing current. The converter transformer quantity protection device controls the operating state of the AC station-side switch and the converter transformer valve-side circuit breaker according to the transformer head-end bushing current, tail-end bushing current, and neutral point current. The converter transformer non-quantity protection device controls the operating state of the AC station-side switch and the converter transformer valve-side circuit breaker according to the transformer body oil temperature and gas information flow. Among them, the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device are also used to simultaneously send a trip signal to the interface device of the substation through the optical fiber transmission module. The interface device instantly starts the trip command when receiving the same trip signals from the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device, delays the alarm when receiving different trip signals from the converter transformer electric quantity protection device and the converter transformer non-electric quantity protection device, and delays the start of the trip command when only receiving the trip signal from the converter transformer electric quantity protection device or the converter transformer non-electric quantity protection device.

2. A commutation transformer protection system without grid-side switches in a station, characterized in that: The method for implementing the converter transformer protection of the non-grid-side switch within the station as claimed in claim 1, wherein the system includes: a substation and a converter station electrically connected to the substation; the substation includes a transmission line and a first line protection device arranged on the transmission line; the converter station includes a transformer, and a second line protection device, a converter transformer quantity protection device and a converter transformer non-quantity protection device electrically connected to the transformer respectively.

3. The commutation transformer protection system for non-grid side switches in a station according to claim 2, characterized in that: The first line protection device includes a first controller, and a first current acquisition module, a first output trip module and a first remote trip module electrically connected to the first controller respectively; wherein, the acquisition end of the first current acquisition module is electrically connected to the current detection point of the middle switch and the current detection point of the side switch respectively, the output end of the first output trip module is electrically connected to the circuit breaker and the side circuit breaker respectively, and the first remote trip module performs remote communication with the second line protection device.

4. The commutation transformer protection system for non-grid side switches in a station according to claim 2, characterized in that: The converter station also includes a converter valve side circuit breaker, one end of the transformer is electrically connected to the converter station flexible DC transformer incoming line end of the transmission line, and the other end of the transformer is electrically connected to the converter valve side circuit breaker.

5. The commutation transformer protection system for non-grid side switches in a station according to claim 4, characterized in that: A head-end bushing current detection point is provided on the grid-side head-end bushing of the transformer, a tail-end bushing current detection point is provided on the grid-side tail-end bushing of the transformer, a neutral point current detection point is provided at the neutral point of the transformer, and a valve-side bushing current detection point is provided on the valve-side bushing of the transformer.

6. The commutation transformer protection system for non-grid side switches in a station according to claim 5, characterized in that: The second line protection device includes a second controller, and a second current acquisition module, a second output trip module and a second remote trip module electrically connected to the second controller respectively; wherein, the acquisition end of the second current acquisition module is electrically connected to the head-end bushing current detection point, the output end of the second output trip module is electrically connected to the converter valve side circuit breaker, and the second remote trip module performs remote communication with the first line protection device.

7. The commutation transformer protection system for non-grid side switches in a station according to claim 5, characterized in that: The converter transformer current protection device includes a third controller, and a third current acquisition module and a third output tripping module electrically connected to the third controller respectively; wherein, the acquisition end of the third current acquisition module is electrically connected to the head-end bushing current detection point, the tail-end bushing current detection point and the neutral point current detection point respectively, and the output end of the third output tripping module is electrically connected to the AC station side switch and the converter transformer valve side circuit breaker respectively.

8. The commutation transformer protection system for non-grid side switches in a station according to claim 5, characterized in that: The non-electrical quantity protection device for the converter transformer includes a fourth controller, and a non-electrical quantity collection module and a fourth output tripping module electrically connected to the fourth controller respectively; wherein, the non-electrical quantity collection module is used to collect the main oil temperature and gas information of the transformer, and the output end of the fourth output tripping module is electrically connected to the central switch on the AC station side and the circuit breaker on the valve side of the converter transformer respectively.

9. The commutation transformer protection system for non-grid side switches in a station according to claim 2, characterized in that: The converter transformer electrical quantity protection device and the converter transformer non-electrical quantity protection device both include an optical fiber transmission module, and the substation includes an interface device connected to the two optical fiber transmission modules respectively; wherein, the interface device includes an optical fiber receiving module and a conventional outlet module connected to the optical fiber receiving module, and the conventional outlet module is used to connect to the circuit breaker protection operation box that controls the working status of the circuit breaker and the side circuit breaker.

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