Distributed ice melting device topological structure suitable for ultra-high voltage transmission line

Abstract

A distributed ice melting device topological structure suitable for an ultra-high voltage power transmission line comprises a plurality of ice melting sub-modules arranged in a distributed mode, and each ice melting sub-module comprises a single-turn coupling transformer, a metal oxide voltage limiter, a bypass switch, a filter, an H-bridge current converter and a direct-current capacitor. A primary winding of the single-turn coupling transformer is directly formed by split sub-conductors of the ultra-high voltage power transmission line, and a secondary winding of the single-turn coupling transformer is electrically connected with other parts of the ice melting sub-modules, so that the ice melting sub-modules are connected in series on the split sub-conductors of the power transmission line in a distributed manner; the H-bridge current converter is electrically connected with the direct-current capacitor, and the direct-current capacitor provides smooth direct-current voltage for the H-bridge current converter; the filter is connected in series with the H-bridge current converter, the bypass switch is connected in parallel with the H-bridge current converter, and the metal oxide voltage limiter is connected in parallel with the line side output end of the ice melting sub-module; and the ice melting sub-modules adjust the current of the corresponding split sub-conductors by changing the equivalent impedance of the ice melting sub-modules, so that accurate ice melting of the ice-coated split sub-conductors is realized, and the overall current and the transmission power of the power transmission line are kept unchanged. The technical problem to be solved by the invention is to provide the distributed ice melting device topological structure suitable for the ultra-high voltage power transmission line, and the technical problem that the existing ice melting technology cannot realize accurate ice melting and non-power-cut operation on an ice coating section on the ultra-high voltage power transmission line is solved. And normal transmission of the line is affected due to overlarge capacity demand, line overcurrent or incapability of three-phase synchronous ice melting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of overhead transmission line ice melting, and particularly relates to a distributed ice melting device topology structure suitable for super-high voltage transmission lines. BACKGROUND

[0002] The super-high voltage transmission lines in China widely pass through high-cold mountainous areas and micro-meteorological icing zones, and icing disasters have become one of the core challenges threatening the safety of power grids. Icing not only increases the weight of the conductor, but also easily causes conductor breakage and tower collapse, and can also cause the flashover voltage of insulators to decrease, thereby significantly increasing the risk of power grid failure and economic losses. However, the current ice melting technology has structural defects, and there is a gap in the distributed topology adaptation: AC ice melting requires full-section operation, and the power supply capacity required for super-high voltage lines is several times the actual ice melting power, far exceeding the carrying capacity of the power grid; although DC ice melting reduces the capacity requirement, it cannot operate synchronously in three phases, and the commutation operation prolongs the time consumption, and the traditional connection in the multi-terminal DC system of the super-high voltage cannot conduct the ice melting circuit. Although sectional DC ice melting can reduce the device capacity, it lacks the support of precise control of the adaptive distributed topology; the exploration of distributed ice melting in the distribution network field cannot be upgraded and applied because the problems of suppression of induced overvoltage and lightning insulation coordination in the super-high voltage scenario have not been solved. Therefore, the present application provides a distributed ice melting device topology structure suitable for super-high voltage transmission lines, which can realize precise, efficient and uninterrupted ice melting operation, and has great significance for ensuring the reliable operation of the power grid under extreme weather conditions. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a distributed ice melting device topology structure suitable for super-high voltage transmission lines, which solves the technical problem that the existing ice melting technology cannot realize precise ice melting for icing sections, uninterrupted operation on super-high voltage transmission lines, and the problem that the normal transmission of the line is affected due to excessive capacity requirement, overcurrent of the line or inability to melt ice in three phases.

[0004] To solve the above technical problems, the technical scheme adopted by the present application is: a distributed ice melting device topology suitable for an extra-high voltage transmission line, comprising a plurality of ice melting sub-modules distributedly arranged, each of the ice melting sub-modules comprising a single-turn coupling transformer, a metal oxide voltage limiter, a bypass switch, a filter, an H-bridge converter and a DC capacitor; a primary winding of the single-turn coupling transformer is directly formed by split sub-conductors of the extra-high voltage transmission line, and a secondary winding is electrically connected with the rest of the components of the ice melting sub-module, so that the ice melting sub-modules are distributedly connected in series on the split sub-conductors of the transmission line; the H-bridge converter is electrically connected with the DC capacitor, and the DC capacitor provides smooth DC voltage for the H-bridge converter; the filter is connected in series with the H-bridge converter, the bypass switch is connected in parallel with the H-bridge converter, and the metal oxide voltage limiter is connected in parallel at a line side output end of the ice melting sub-module; the ice melting sub-module adjusts the current of the corresponding split sub-conductor by changing its equivalent impedance, so as to realize accurate ice melting of the iced split sub-conductor, and maintain the overall current and transmission power of the transmission line unchanged.

[0005] Preferably, the primary winding of the single-turn coupling transformer is equivalent to a single-turn structure, and the ice melting sub-module is detachably connected with the split sub-conductor through a clamp structure, without the need for physical modification of the split sub-conductor, so as to realize plug and play.

[0006] Preferably, the metal oxide voltage limiter is composed of a non-linear metal oxide resistor sheet, for limiting overvoltage generated at the output end of the ice melting sub-module during power system failure.

[0007] Preferably, the bypass switch is a mechanical bypass switch, which is closed when the H-bridge converter is in a blocking, failure or maintenance state, so as to bypass the H-bridge converter and ensure normal operation of the transmission line.

[0008] Preferably, the filter comprises a filter capacitor and a filter inductor, which are connected in series or parallel to form a filter circuit, for reducing harmonic voltage injected into the transmission line and suppressing fault current invading the ice melting sub-module.

[0009] Preferably, the H-bridge converter is composed of full-controlled power electronic devices IGBT, and the H-bridge converter outputs inductive equivalent impedance or capacitive equivalent impedance, so as to realize increase or decrease of the current of the corresponding split sub-conductor by adjusting the type and size of the equivalent impedance.

[0010] Preferably, the installation position of the ice melting sub-module is within a single span of a strain tower section of the extra-high voltage transmission line, and the ice melting sub-module is installed on each of the n split sub-conductors of the single-phase line, without the need for power-off operation and structural modification of the transmission line during the installation process.

[0011] Preferably, the split conductors of the ultra-high voltage transmission line are segmented along the length of the line, and the spacers in each segment of the split conductor are insulated. The spacers at the beginning and end of the segment remain uninsulated, so that the de-icing current flows only in a single segment of the split conductor, avoiding the current from affecting non-icing areas across segments.

[0012] Preferably, when the capacity of a single ice-melting sub-module on a single split sub-conductor is insufficient, a segmented installation method is adopted, in which multiple ice-melting sub-modules are installed at intervals along the length direction on the same split sub-conductor to distribute the total capacity of the device and meet the ice-melting power requirements.

[0013] Preferably, the topology is applied to a three-phase ultra-high voltage transmission line, and the de-icing sub-module is installed on each of the split conductors in the three-phase line. Through the coordinated control of the de-icing sub-modules on each phase and each split conductor, the three-phase line can be de-iced simultaneously, shortening the total de-icing time.

[0014] This invention provides a distributed de-icing device topology suitable for ultra-high voltage transmission lines, which has the following advantages: 1. Achieve precise ice melting to avoid resource waste. To address the energy and equipment resource waste caused by the existing "full-section operation" of AC ice melting, this patent achieves precise and targeted ice melting through two major designs: By modifying the split conductor with insulating spacers, the de-icing current is restricted to the icing section and does not affect the non-icing area. By distributing the de-icing device in series with specific split conductors through a single-turn coupling transformer, de-icing can be performed on single or multiple ice-covered conductors individually, without the need to operate on the entire line or the entire phase, thus greatly reducing ineffective energy consumption and equipment investment.

[0015] 2. Supports uninterrupted power supply operations to ensure continuous power supply from the grid. Existing ice-melting technologies (such as partial DC ice-melting and traditional AC ice-melting) require power outages for modification or operation, affecting the reliability of the power grid. This patent is granted through: The single-turn coupled transformer features "clamp-type plug-and-play installation," requiring no physical modification to the split conductors and eliminating the need for power outages during installation. During the ice melting process, the device is coupled to the line without contact and maintains the normal parameters of the line through impedance coordination, ensuring uninterrupted power transmission throughout the process. This completely solves the industry pain point of "inevitable power outage during ice melting" and ensures continuous power supply to the power grid under extreme weather conditions.

[0016] 3. Improve grid compatibility and eliminate operational risks. Existing AC de-icing methods suffer from problems such as "large capacity requirements, overcurrent in non-iced lines, and disruption to power grid operation." This patent completely avoids these issues through an impedance coordination mechanism. The de-icing device on the icing sub-conductor reduces the equivalent impedance to increase the de-icing current, while the device on the non-icing sub-conductor simultaneously increases the equivalent impedance to reduce the current, ultimately maintaining the total line current, overall equivalent impedance, and transmission power unchanged. It eliminates the need for multiple circuits in series to match impedances, avoids the need for large-scale load transfer, prevents overcurrent damage to conductors on non-icing lines, and eliminates the need to change the original operation mode of the power grid, thus reducing interference and fault risks to the power grid.

[0017] 4. Improve ice melting efficiency and shorten emergency response time. Addressing the shortcomings of DC ice melting, such as "inability to operate three-phase synchronously and long commutation time," this patent achieves highly efficient ice melting: The topology can be directly adapted to three-phase ultra-high voltage lines. Each split conductor of the three-phase line is equipped with an ice-melting device, and the three phases can be ice-melted simultaneously through coordinated control. No phase-by-phase switching is required, which greatly reduces the total time for de-icing. It is especially suitable for emergency response when icing disasters occur suddenly, reducing the continuous threat of icing to the power grid.

[0018] 5. Enhanced safety protection, adaptable to ultra-high voltage scenarios Distributed de-icing in the power distribution network sector is difficult to upgrade due to its inability to solve the "overvoltage and lightning protection insulation" problems of ultra-high voltage and extra-high voltage networks. This patent provides targeted optimization: A metal oxide voltage limiter is configured and connected in parallel to the output terminal of the ice melting sub-module to effectively limit the overvoltage generated during power system faults, thereby preventing device damage or line insulation breakdown. Filters (including capacitors and inductors) can reduce the harmonic voltage injected into the line, suppress the intrusion fault current, ensure the power quality and insulation safety of ultra-high voltage lines, and fill the technological gap in distributed de-icing of ultra-high voltage lines.

[0019] 6. Enhance the flexibility and reliability of the device to adapt to complex working conditions. This patented design is highly adaptable to the actual working conditions of ultra-high voltage and extra-high voltage lines, where "the space for split conductors is narrow and the load-bearing capacity is limited." When the capacity is insufficient, the total capacity can be distributed through "segmented installation" to meet the high-power de-icing requirements without exceeding the space and load-bearing limits of the sub-conductors. A bypass switch is configured so that the H-bridge converter can be bypassed when it is locked, malfunctions, or under maintenance, ensuring the normal operation of the transmission line, avoiding line outages due to equipment failure, and improving the overall system reliability. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2This is a schematic diagram of the coupled installation of the distributed ice-melting device of the present invention; Figure 3 This is a schematic diagram of the modification of the four-splitter conductor spacer bar of the present invention; Figure 4 This is a schematic diagram illustrating the working principle of the distributed ice-melting device of the present invention. Figure 5 This is a vector diagram of the distributed ice-melting device of the present invention. Detailed Implementation

[0021] like Figure 1 As shown, a distributed de-icing device topology suitable for ultra-high voltage (UHV) transmission lines includes several distributed de-icing sub-modules. Each de-icing sub-module includes a single-turn coupling transformer, a metal oxide voltage limiter, a bypass switch, a filter, an H-bridge converter, and a DC capacitor. The primary winding of the single-turn coupling transformer is directly formed from the split conductors of the UHV transmission line, and the secondary winding is electrically connected to the remaining components of the de-icing sub-module, so that the de-icing sub-modules are distributed in series on each split conductor of the transmission line. The H-bridge converter is electrically connected to the DC capacitor, and the DC capacitor provides a smooth DC voltage to the H-bridge converter. The filter is connected in series with the H-bridge converter, the bypass switch is connected in parallel with the H-bridge converter, and the metal oxide voltage limiter is connected in parallel at the line-side output terminal of the de-icing sub-module. The de-icing sub-module adjusts the current of the corresponding split conductor by changing its equivalent impedance, thereby achieving precise de-icing of the iced split conductors while maintaining the overall current and transmission power of the transmission line unchanged. Through the collaborative design of distributed de-icing sub-modules, precise de-icing of ice-covered split conductors was achieved while maintaining the overall current and transmission power of the transmission line unchanged, solving the problem that traditional de-icing technology affects the normal operation of the line; the integrated design of each component provides a complete and adaptable topology solution for de-icing of ultra-high voltage lines.

[0022] Preferably, the primary winding of the single-turn coupled transformer is equivalent to a single-turn structure, and the de-icing sub-module is detachably connected to the split sub-conductor via a clamp structure, eliminating the need for physical modification of the split sub-conductor and achieving plug-and-play functionality. The single-turn equivalent structure and clamp-type detachable connection of the single-turn coupled transformer eliminate the need for physical modification of the split sub-conductor, achieving "plug-and-play" functionality, significantly reducing installation difficulty and interference with the line, and is particularly suitable for uninterrupted power supply operations.

[0023] Preferably, the metal oxide voltage limiter is composed of nonlinear metal oxide resistors and is used to limit the overvoltage generated at the output terminal of the de-icing submodule during power system faults. The metal oxide voltage limiter, composed of nonlinear resistors, can specifically limit overvoltages during faults, preventing damage to the de-icing submodule and transmission lines due to overvoltage, and improving the safety of the device under complex power grid conditions.

[0024] Preferably, the bypass switch is a mechanical bypass switch. When the H-bridge converter is in a locked, faulty, or maintenance state, the bypass switch closes, bypassing the H-bridge converter and ensuring the normal operation of the transmission line. This ensures the transmission line continues to operate regardless of the device's status, improving the system's reliability and fault tolerance.

[0025] Preferably, the filter includes a filter capacitor and a filter inductor, which are connected in series or parallel to form a filter circuit to reduce harmonic voltage injected into the transmission line and suppress fault current entering the de-icing submodule. Through the combination of capacitor and inductor, the filter can both reduce harmonic voltage injected into the line to ensure power quality and suppress fault current entering the de-icing submodule, thus enhancing the device's tolerance to grid disturbances.

[0026] Preferably, the H-bridge converter is composed of fully controllable power electronic devices (IGBTs). The H-bridge converter outputs inductive or capacitive equivalent impedance. By adjusting the type and magnitude of the equivalent impedance, the current in the corresponding split conductor can be increased or decreased. The H-bridge converter uses fully controllable IGBT devices, which can flexibly output inductive or capacitive equivalent impedance. By adjusting the impedance type and magnitude, the current in the split conductor can be precisely controlled, adapting to the de-icing requirements under different icing levels and improving the controllability of de-icing.

[0027] Preferably, the ice-melting sub-module is installed within a single span of the tension tower section of the ultra-high voltage (UHV) transmission line, and the ice-melting sub-module is installed on each of the n split conductors of the single-phase line. The installation process requires no power outage or structural modification of the transmission line. By clearly defining the installation location of the ice-melting sub-module within the tension tower section and ensuring corresponding installation on each of the n split conductors of the single-phase line, while avoiding power outages and line structural modifications, the system adapts to the structural characteristics of UHV lines and avoids any impact on power supply.

[0028] Preferably, the split conductors of the ultra-high voltage transmission line are segmented along the length of the line, and the spacers within each segment are insulated. The spacers at the beginning and end of each segment remain uninsulated, ensuring that the de-icing current flows only within a single segment of the split conductor, preventing current from crossing segments and affecting non-icing areas. By segmenting the split conductors and insulating the spacers, the de-icing current is restricted to flowing only within a single segment of the split conductor, preventing current from crossing segments and affecting non-icing areas. This achieves precise control of the de-icing area and reduces ineffective energy consumption.

[0029] Preferably, when the capacity of a single ice-melting submodule on a single split conductor is insufficient, a segmented installation method is adopted, in which multiple ice-melting submodules are installed at intervals along the length of the same split conductor to distribute the total capacity of the device and meet the ice-melting power requirements. When the capacity of a single ice-melting submodule is insufficient, the segmented installation method distributes the total capacity, meeting the high-power ice-melting requirements without exceeding the limitations of line space and load-bearing capacity, thus enhancing the adaptability of the device to different ice-melting power scenarios.

[0030] Preferably, the topology is applied to three-phase ultra-high voltage transmission lines. Each split conductor in the three-phase line is equipped with a corresponding de-icing sub-module. Through the coordinated control of the de-icing sub-modules on each phase and each split conductor, simultaneous de-icing of the three-phase line is achieved, shortening the total de-icing time. This supports the application of three-phase ultra-high voltage lines, achieving simultaneous de-icing of all three phases through the coordinated control of the de-icing sub-modules on each phase and each split conductor. This solves the problem of the long de-icing time of traditional phase-by-phase de-icing technology, significantly shortening the total de-icing time and improving emergency response efficiency.

[0031] The primary winding of the transformer used in the distributed de-icing device is directly formed by split sub-conductors, equivalent to a single-turn winding. Therefore, no physical modification to the split sub-conductors is required to install the distributed de-icing device clamps on it, offering excellent convenience and flexibility. During installation, the distributed de-icing device is clamped onto the n sub-conductors of a single-phase line within one span of the tension tower section using a single-turn coupling transformer. Figure 2 As shown, this installation method allows for plug-and-play operation without requiring modification of the transmission line or power outages. Due to space constraints and weight limitations between the sub-conductors, the device cannot achieve the required capacity; therefore, segmented installation can be used to distribute the total capacity of the device.

[0032] The split conductor is divided into segments, and the spacers within each segment are insulated. The spacers at the beginning and end of each segment remain uninsulated. Taking a four-split conductor as an example... Figure 3 As shown. In this way, the de-icing current is only restricted to moving within this segment.

[0033] Based on the topology and installation method of the distributed ice-melting device, its working principle can be equivalent to an impedance connected in series with n split-wires, such as... Figure 4 As shown. This transmission line is a single-phase transmission line. Line current; The equivalent impedance of the transmission line on the left side of tower 1; The equivalent impedance of the transmission line on the right side of tower 2; , ... The equivalent impedance on the n split sub-conductors; , ... The equivalent impedance generated by the distributed ice melting device; , ... Let be the line current flowing through n split sub-conductors.

[0034] Distributed de-icing devices are connected in series on the iced line, increasing the de-icing current by changing the equivalent impedance. This is used for the iced sub-conductors. Taking ice melting as an example, it is connected in series with the sub-conductor. Distributed ice melting devices need to reduce equivalent impedance To reduce the size of the sub-wire To increase the line current by increasing the total impedance ,Right now (1) To maintain the overall line parameters unchanged, without affecting the line current or altering the line transmission power, it is necessary to connect the sub-conductor in series. ... Distributed ice melting devices increase equivalent impedance ... To increase the size of the sub-conductor ... To reduce line current by reducing total impedance ... ,Right now (2) Therefore, by coordinating the operation of distributed de-icing devices connected in series on different split conductors, the ice-covered split conductors are de-iced sequentially without changing the line current or the overall line parameters. Three-phase lines can be de-iced simultaneously, significantly reducing the de-icing time.

[0035] Since the distributed de-icing device draws energy from the transmission line, it needs to maintain a stable DC capacitor voltage. Only when the DC capacitor voltage is stable can the distributed de-icing device operate normally. Therefore, the distributed de-icing device has only one degree of control freedom, that is, it can only generate capacitive or inductive reactance. The phasor diagram of the working principle of the distributed de-icing device is as follows: Figure 5 As shown. The equivalent capacitive or inductive reactance generated by a distributed de-icing device is determined by its device capacity, i.e. (3) in, Apparent capacity of distributed ice melting devices This is the line's rated voltage.

[0036] This invention proposes a distributed de-icing device topology suitable for ultra-high voltage (UHV) transmission lines. Based on its single-turn coupled transformer, it can be distributed and contactlessly engaged on iced transmission lines. By modifying the insulating spacers, the distributed de-icing device can de-ic a specific section of the iced line without affecting the entire transmission line. The topology of the distributed de-icing device is based on an H-bridge converter, which can generate inductive or capacitive reactance. This reduces the total impedance of the iced line to increase the de-icing current, thus de-icing the line. Simultaneously, it increases the total impedance of the non-de-iced lines to reduce the line current, maintaining a constant total line current, i.e., unchanged line parameters, and not affecting the transmission power of the UHV transmission line.

[0037] This distributed de-icing device topology, applicable to ultra-high voltage and extra-high voltage transmission lines, offers advantages over traditional AC de-icing methods. It eliminates the need to alter the transmission power of the power system's transmission lines, avoids the issue of overall line current exceeding limits, and ensures high safety. It can de-ic a specific iced section without affecting the entire line, offering excellent flexibility. Compared to DC de-icing methods, it enables simultaneous de-icing of three-phase lines, with shorter de-icing time and higher efficiency. Furthermore, it eliminates the need for power outages, resulting in high economic efficiency and reliability.

[0038] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A topology of distributed ice-melting device suitable for EHT power transmission lines, characterized in that: The ice melting sub-module includes a single-turn coupling transformer, a metal oxide voltage limiter, a bypass switch, a filter, an H-bridge converter and a DC capacitor.

2. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, wherein: The primary winding of the single-turn coupling transformer is directly formed by the split sub-conductor of the ultra-high voltage transmission line, and the secondary winding is electrically connected with the remaining components of the ice melting sub-module, so that the ice melting sub-module is distributed and connected in series on each split sub-conductor of the transmission line.

3. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, characterized in that: The H-bridge converter is electrically connected with the DC capacitor, and the DC capacitor provides smooth DC voltage for the H-bridge converter.

4. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, wherein: The filter is connected in series with the H-bridge converter, and the bypass switch is connected in parallel with the H-bridge converter.

5. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, wherein: The metal oxide voltage limiter is connected in parallel with the line side output end of the ice melting sub-module.

6. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, characterized in that: The primary winding of the single-turn coupling transformer is equivalent to a single-turn structure, and the ice melting sub-module is detachably connected with the split sub-conductor through a clamp structure, without the need for physical modification of the split sub-conductor, so that the ice melting sub-module can be used immediately.

7. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, characterized in that: The metal oxide voltage limiter is composed of a non-linear metal oxide resistor sheet, and is used to limit the overvoltage generated at the output end of the ice melting sub-module during power system failure.

8. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, characterized in that: The bypass switch is a mechanical bypass switch, which is closed when the H-bridge converter is in a locked, fault or maintenance state, so as to bypass the H-bridge converter and ensure the normal operation of the transmission line.

9. The topology of the distributed ice-melting device suitable for EHV / UHV transmission lines according to claim 1, characterized in that: The filter includes a filter capacitor and a filter inductor, which are connected in series or parallel to form a filter circuit, and are used to reduce the harmonic voltage injected into the transmission line and suppress the fault current invading the ice melting sub-module.

10. The topology of the distributed ice-melting device suitable for EHT power transmission lines according to any one of claims 1-9, characterized in that: The H-bridge converter is composed of all-controllable power electronic devices IGBT, and the H-bridge converter outputs inductive equivalent impedance or capacitive equivalent impedance, so as to increase or decrease the current of the corresponding split sub-conductor by adjusting the type and size of the equivalent impedance. The installation position of the ice melting sub-module is within a single span of the strain tower section of the ultra-high voltage transmission line, and the ice melting sub-module is installed on each of the n split sub-conductors of the single-phase line, without the need for power-off operation and structural modification of the transmission line during the installation process. The split conductors of the ultra-high voltage transmission line are segmented along the length direction of the line, the spacer rods in each segment of the split conductor are insulated, and the spacer rods at the head and tail of the segment are kept non-insulated, so that the ice melting current only flows in a single segment of the split conductor, and the current across the segments does not affect the non-iced area. When the capacity of a single ice melting sub-module on a single split sub-conductor is insufficient, multiple ice melting sub-modules are installed on the same split sub-conductor along the length direction at intervals, so as to share the total capacity of the device and meet the ice melting power demand. The topology structure is applied to a three-phase ultra-high voltage transmission line, and the ice melting sub-module is installed on each split sub-conductor of the three-phase line. Through the coordinated control of the ice melting sub-modules on each phase and each split sub-conductor, the three-phase line is simultaneously melted, and the total ice melting time is shortened.

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