Small capacitor power extraction solid-sealed terminal

Abstract

This utility model relates to the field of power technology, and in particular to a small capacitor-driven solid-sealed terminal post, comprising: a vacuum interrupter, the input end of which is connected to the incoming side of a medium-voltage power grid; a transition piece and a spring contact finger, movably connected to the output end of the vacuum interrupter; a conductive rod, connected to the spring contact finger and extending to the outgoing side of the medium-voltage power grid, the spring contact finger being used to realize the electrical connection between the transition piece and the conductive rod; and a capacitor-driven power supply group, disposed inside the solid-sealed terminal post, the capacitor-driven power supply group comprising a capacitor bank composed of multiple ceramic capacitors connected in series and a transformer electrically connected to the capacitor bank; by using a capacitor bank composed of multiple ceramic capacitors connected in series as the core component of the capacitor-driven power supply group, and ensuring that the capacitor bank and the transformer electrically connected to it have temperature resistance matching the curing temperature of the epoxy resin body, the operational reliability and safety of the equipment are significantly improved.

Description

Technical Field

[0001] This utility model relates to the field of power technology, and in particular to a solid-sealed terminal block for power extraction from small capacitors. Background Technology

[0002] As a crucial component of the energy internet, the power distribution network is a key link in ensuring power supply and improving power service levels. With the widespread integration of new power facilities such as electric vehicles, distributed energy sources, microgrids, and energy storage devices, and the continuous growth of electricity market demand, higher requirements are being placed on the security, economy, and adaptability of the power distribution network. To achieve the intelligentization and modernization of the power distribution network, the application of intelligent terminal equipment is essential. Solid-sealed poles, as core components of the medium-voltage power grid, play a vital role in extracting current and voltage signals from the medium-voltage grid and providing auxiliary power.

[0003] However, the power supply used in existing solid-sealed terminals typically employs a single high-voltage capacitor or a film capacitor. These capacitors have significant technical drawbacks. First, single high-voltage capacitors or film capacitors have low withstand voltage capabilities. Under the high-voltage, high-current operating environment of medium-voltage power grids, they are prone to breakdown due to voltage fluctuations or transient overvoltages, leading to equipment failure and severely impacting the reliability and safety of the distribution network. Second, these capacitors have a narrow operating temperature range and poor temperature resistance. Their performance deteriorates significantly or even fails under conditions of large ambient temperature variations or high heat generation from the equipment itself, thus limiting the applicability and long-term stability of solid-sealed terminals. More importantly, solid-sealed terminals typically require integral encapsulation with epoxy resin during manufacturing to provide excellent insulation and mechanical protection. However, the temperature resistance of existing capacitors often does not match the curing temperature of epoxy resin. This means that during the high-temperature curing process of epoxy resin, the capacitor may be damaged, resulting in a decrease in its electrical performance or damage to its internal structure. This, in turn, affects the insulation performance and service life of the entire solid-sealed terminal block, and may even cause the failure of secondary solid-sealed film capacitors, increasing the complexity of the manufacturing process and the defect rate of the products.

[0004] In summary, the capacitors used in existing solid-sealed terminals for power generation have significant shortcomings in terms of voltage withstand capability, temperature resistance, and compatibility with the sealing materials. These issues collectively lead to reduced reliability, shortened lifespan, and increased manufacturing costs for solid-sealed terminals. Therefore, existing technologies urgently need improvement to address these problems. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a small capacitor power extraction solid-sealed electrode.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a small capacitor power extraction solid-sealed terminal, applied to a medium-voltage power grid, extracting current and voltage signals and power supply from the medium-voltage power grid, including:

[0007] A vacuum interrupter, the input end of which is connected to the incoming side of the medium-voltage power grid;

[0008] The transition piece and spring contact finger are movably connected to the output end of the vacuum interrupter;

[0009] A conductive rod is connected to a spring contact finger and extends to the output side of the medium-voltage power grid. The spring contact finger is used to realize the electrical connection between the transition piece and the conductive rod.

[0010] Current and voltage sensor arrays are used to monitor the operating parameters of medium-voltage power grids;

[0011] A capacitor-powered power supply group is disposed inside the solid-sealed pole. The capacitor-powered power supply group includes a capacitor bank composed of multiple ceramic capacitors connected in series and a transformer electrically connected to the capacitor bank.

[0012] Epoxy resin is used to encapsulate the vacuum interrupter, transition piece, spring contact finger, conductive rod, current and voltage sensor group, and capacitor power supply group inside the encapsulated pole. The capacitor bank formed by multiple ceramic capacitors connected in series and the transformer have temperature resistance properties that match the curing temperature of the epoxy resin body.

[0013] Preferably, it also includes silicone rubber, which is coated with an epoxy resin outer layer for UV protection.

[0014] Preferably, the current-voltage sensor group includes:

[0015] The incoming voltage sensor has its high-voltage end connected to the incoming side of the medium-voltage power grid and its low-voltage end grounded.

[0016] The voltage sensor on the outgoing side has a conductive rod connected to the high-voltage end and is grounded at the low-voltage end.

[0017] Zero-sequence current sensor and phase current sensor are mounted on a conductive rod;

[0018] Ceramic capacitors are integrated into the input-side voltage sensor and the output-side voltage sensor.

[0019] Preferably, the circuit connection of the current and voltage sensor group includes:

[0020] The current sensor sampling resistor, connected in parallel with the zero-sequence current sensor and the phase current sensor, is used to convert the current signal into a voltage signal;

[0021] The current and voltage sensor circuit board is used to integrate signal conditioning circuitry and connect sampling resistors, input-side voltage sensors, and output-side voltage sensors.

[0022] Preferably, the current and voltage sensor group further includes a current and voltage sensor fixing component for fixing the sensor assembly.

[0023] Preferably, the current and voltage sensor group outputs detection signals through a current and voltage sensor aviation socket.

[0024] Preferably, the circuit topology of the capacitor-powered power supply group includes a first topology or a second topology.

[0025] Preferably, the first topology is connected to the incoming side of the medium-voltage power grid via a conductor and is connected in parallel with the vacuum interrupter.

[0026] Preferably, the second topology is connected to the end of the conductive rod via a wire and is connected in parallel with the voltage sensor on the output side.

[0027] Preferably, the capacitor-powered power supply group outputs power through an aviation socket, and the power source can be selected from the incoming or outgoing side.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] This invention effectively solves the aforementioned technical problems by employing a capacitor bank composed of multiple ceramic capacitors connected in series as the core component of the capacitor-powered power supply group. It ensures that the capacitor bank and the transformer electrically connected to it possess temperature resistance matching the curing temperature of the epoxy resin, thereby enhancing the overall voltage withstand capability of the capacitor-powered power supply group. Specifically, the series connection of multiple ceramic capacitors significantly improves the overall voltage withstand capability of the capacitor-powered power supply group, enabling it to better adapt to the high-voltage, high-current operating environment of medium-voltage power grids. This greatly reduces the risk of breakdown due to voltage fluctuations or transient overvoltages, significantly improving the operational reliability and safety of the equipment. Simultaneously, the excellent temperature resistance of the ceramic capacitors, combined with their good matching with the curing temperature of epoxy resin, ensures the integrity of the capacitors during the manufacturing and sealing process, avoiding high-temperature damage. It also ensures that the equipment maintains stable performance over a wide range of ambient temperatures and even under conditions of high heat generation, greatly expanding the applicability and long-term stability of the sealed terminals.

[0030] Furthermore, this design eliminates problems such as decreased electrical performance, internal structural damage, and secondary sealing failure caused by incompatibility between capacitors and sealing materials in existing technologies. It simplifies the manufacturing process and reduces product defect rates and manufacturing costs. Therefore, the small capacitor power-taking sealed terminal of this invention achieves significant improvements in voltage resistance, temperature resistance, and manufacturing compatibility, providing a more reliable and efficient core component for the intelligentization and modernization of power distribution networks. Attached Figure Description

[0031] Figure 1 Full cross-sectional view of the solid-sealed terminal block for power extraction from the small capacitor on the incoming line side;

[0032] Figure 2 Schematic diagram of a solid-sealed electrode for power extraction from a small capacitor on the incoming line side;

[0033] Figure 3 Full cross-sectional view of the solid-sealed terminal block for power extraction from the small capacitor on the outgoing side;

[0034] Figure 4 Schematic diagram of a solid-sealed terminal block for power extraction from a small capacitor on the outgoing side.

[0035] In the diagram: 1. Vacuum interrupter; 2. Transition component; 3. Spring contact finger; 4. Conductive rod; 5. Epoxy resin; 6. Silicone rubber; 7. Incoming line voltage sensor; 8. Outgoing line voltage sensor; 9. Zero-sequence current sensor; 10. Phase current sensor; 11. Current and voltage sensor circuit board; 12. Current and voltage sensor mounting component. Detailed Implementation

[0036] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0037] Traditional solid-sealed terminals, when applied to medium-voltage power grids, typically use a single high-voltage capacitor or a film capacitor as the power source. However, these single high-voltage capacitors or film capacitors often suffer from low withstand voltage and limited operating temperature ranges. Furthermore, their temperature resistance is incompatible with the curing temperature of the epoxy resin used in the solid-sealed terminal, which may lead to problems during secondary sealing, thereby affecting the overall service life and reliability of the terminal. Failure to address these issues will directly impact the safety, economy, and adaptability of the distribution network, a problem that is particularly prominent given the current increasing demands for reliability, user-friendliness, and cost-effectiveness in distribution networks.

[0038] To address this issue, this application proposes a small-capacitor power extraction solid-sealed terminal block, applied to medium-voltage power grids, designed to extract current signals, voltage signals, and power supply from the medium-voltage grid. This solid-sealed terminal block effectively solves problems in existing technologies such as low capacitor withstand voltage, poor temperature matching, and short service life by optimizing the internal capacitor structure and encapsulation materials, significantly improving the overall performance and reliability of the solid-sealed terminal block. The small-capacitor power extraction solid-sealed terminal block disclosed in this embodiment is mainly used in medium-voltage power grids, serving as a key component in the distribution network, responsible for circuit switching, monitoring grid operation status, and providing auxiliary power to related equipment. Medium-voltage power grids typically refer to power networks with voltage levels between 1kV and 35kV, and are a crucial link connecting high-voltage transmission networks and low-voltage distribution networks. As a core component of medium-voltage switchgear, the solid-sealed terminal block's internal electrical components are integrally solidified in insulating material to provide excellent insulation performance and mechanical strength. The term "power acquisition" as used in this application refers to obtaining low-voltage power from a high-voltage power grid for use by internal sensors, communication modules, or other auxiliary equipment; "current signal" and "voltage signal" refer to real-time electrical parameters used to reflect the operating status of the power grid, which are crucial for the monitoring, control, and fault diagnosis of the power grid.

[0039] like Figures 1 to 4 The small capacitor-type solid-sealed terminal shown is used in a medium-voltage power grid to extract current and voltage signals and power supply from the medium-voltage grid, including:

[0040] Vacuum interrupter 1, the input end of vacuum interrupter 1 is connected to the incoming side of medium voltage power grid;

[0041] Transition piece 2 and spring contact finger 3 are movably connected to the output end of vacuum interrupter 1;

[0042] The conductive rod 4 is connected to the spring contact finger 3 and extends to the output side of the medium voltage power grid. The spring contact finger 3 is used to realize the electrical connection between the transition piece 2 and the conductive rod 4.

[0043] Current and voltage sensor arrays are used to monitor the operating parameters of medium-voltage power grids;

[0044] The capacitor-powered power supply is located inside the solid-sealed pole. The capacitor-powered power supply includes a capacitor bank consisting of multiple ceramic capacitors connected in series and a transformer electrically connected to the capacitor bank.

[0045] Epoxy resin 5 is used to encapsulate the vacuum interrupter 1, transition piece 2, spring contact finger 3, conductive rod 4, current and voltage sensor group and capacitor power supply group inside the solidified electrode column. The capacitor bank composed of multiple ceramic capacitors connected in series and the transformer have temperature resistance properties that match the curing temperature of the epoxy resin 5 body.

[0046] The vacuum interrupter 1 is one of the core components of the solid-sealed pole, and its input end is designed to connect to the incoming side of the medium-voltage power grid. The main function of the vacuum interrupter 1 is to achieve rapid circuit breaking and closing under high-voltage conditions. Through the excellent insulation properties of the vacuum medium, it effectively suppresses electric arcs, ensuring the safety and reliability of switch operations. For example, when a power grid fault occurs or maintenance is required, the vacuum interrupter 1 can quickly cut off the current, protecting power grid equipment from damage.

[0047] Furthermore, the transition element 2 and the spring contact finger 3 are movably connected to the output end of the vacuum interrupter 1. The transition element 2 typically serves as a structural transition and electrical connection, while the spring contact finger 3 is a contact element with good conductivity and elasticity, whose main function is to achieve a reliable electrical connection between the transition element 2 and the conductive rod 4. This movable connection method ensures that a stable electrical path is maintained between the vacuum interrupter 1 and the conductive rod 4 during switching operations, while allowing for a certain amount of mechanical displacement to accommodate tolerances during assembly and operation.

[0048] The conductive rod 4 connects to the spring contact finger 3 and extends to the output side of the medium-voltage power grid. The conductive rod 4 is the main path for current through the solidified pole, and its material is typically a high-conductivity copper or aluminum alloy to ensure low current transmission loss. Through the connection between the spring contact finger 3 and the transition piece 2, the conductive rod 4 can guide the output current of the vacuum interrupter 1 to the output side of the medium-voltage power grid, completing the circuit conduction.

[0049] In addition, the solid-sealed pole is equipped with a current and voltage sensor array, which is mainly used to monitor the operating parameters of the medium-voltage power grid. This sensor array can collect current and voltage signals in the power grid in real time and convert these analog signals into electrical signals that can be processed later. For example, by monitoring these parameters, overloads, short circuits, voltage anomalies, and other conditions in the power grid can be detected in a timely manner, providing data support for the stable operation of the power grid.

[0050] The capacitor-powered power supply is another key component of this application, housed within the solid-sealed terminal block. This power supply includes a capacitor bank composed of multiple ceramic capacitors connected in series and a transformer electrically connected to the capacitor bank. Compared to a single high-voltage capacitor or film capacitor, the capacitor bank composed of multiple ceramic capacitors connected in series has higher voltage withstand capability and superior temperature characteristics, enabling it to better adapt to the complex operating environment of medium-voltage power grids. The transformer converts the high-voltage electrical energy extracted by the capacitor bank into low-voltage power for use by control circuits, sensors, or other auxiliary equipment within the solid-sealed terminal block.

[0051] Finally, epoxy resin 5 is used to encapsulate the vacuum interrupter 1, transition piece 2, spring contact finger 3, conductive rod 4, current and voltage sensor group, and capacitor power supply group inside the solidified electrode post. Epoxy resin 5, as an excellent insulating and encapsulating material, provides superior electrical insulation, mechanical support, and moisture and contamination resistance, thereby protecting the internal components from the influence of the external environment. Notably, the capacitor bank formed by multiple ceramic capacitors connected in series and the transformer have temperature resistance matching the curing temperature of the epoxy resin 5 itself. This characteristic is a key innovation of this application, solving the problem of mismatch between the curing temperature of the capacitor and the epoxy resin in the prior art, avoiding damage to the capacitor performance during the curing process, and thus significantly improving the overall reliability and service life of the solidified electrode post.

[0052] Compared with existing technologies, the small capacitor-driven solid-sealed terminal block of this embodiment has significant advantages. Traditional solid-sealed terminals often use single high-voltage capacitors or film capacitors with insufficient voltage and temperature resistance, making them susceptible to damage during epoxy resin curing and resulting in a shortened product lifespan. This application significantly improves the overall voltage resistance of the capacitors by employing a capacitor bank composed of multiple ceramic capacitors connected in series. Furthermore, these ceramic capacitors and the matching transformer possess temperature resistance matching the curing temperature of epoxy resin. Therefore, during the solidification process, the internal components can withstand high temperatures without performance degradation, ensuring long-term stable operation and a longer service life for the solid-sealed terminal block. This design not only improves equipment reliability but also reduces maintenance costs and power outage risks caused by capacitor failure.

[0053] When using the small capacitor-driven solid-sealed terminal block of this embodiment, its operation is as follows: When the small capacitor-driven solid-sealed terminal block is installed and connected to the medium-voltage power grid, the current from the power grid first enters through the input terminal of the vacuum interrupter 1. The vacuum interrupter 1, as the core switching element, can realize the switching of the circuit according to control commands. Under normal operating conditions, the current flows out from the output terminal of the vacuum interrupter 1, passes through the movable transition member 2 and the spring contact finger 3, and is then transmitted to the conductive rod 4, ultimately extending to the outgoing side of the medium-voltage power grid, forming a complete current path. The spring contact finger 3 ensures a stable electrical connection between the transition member 2 and the conductive rod 4 during this process, maintaining good conductivity even under mechanical stress or temperature changes. Simultaneously, the current and voltage sensor group continuously monitors the current flowing through the conductive rod 4 and the voltage of the power grid. These sensors convert the operating parameters of the medium-voltage power grid into processable electrical signals, which can then be transmitted to an external control or monitoring system for real-time analysis of the power grid's operating status, such as load changes and fault detection. More importantly, the capacitor-driven power supply group plays a self-powering role in this process. The capacitor bank in the capacitor-powered power supply unit consists of multiple ceramic capacitors connected in series, drawing power directly from the high-voltage side of the medium-voltage power grid. Due to the high voltage and temperature resistance of ceramic capacitors, and the fact that multiple capacitors are connected in series further enhance their overall voltage resistance, they can safely and stably draw power from the medium-voltage power grid. The obtained high-voltage power is then transmitted to a transformer electrically connected to the capacitor bank. The transformer converts the high-voltage power into a low-voltage power supply suitable for internal electronic components or external intelligent terminals, and provides electrical isolation to ensure the safety and stability of the output power. All key electrical components, including the vacuum interrupter 1, transition piece 2, spring contact finger 3, conductive rod 4, current and voltage sensor group, and the capacitor-powered power supply unit, are integrally encapsulated in epoxy resin 5 within the solidified electrode post. Epoxy resin 5 not only provides excellent insulation protection, preventing contact between internal components and the external environment, but also gives the solidified electrode post a robust mechanical structure. In particular, the temperature resistance of the capacitor bank and transformer in the capacitor-powered power supply unit is carefully designed to match the curing temperature of epoxy resin 5. This means that during the curing process of epoxy resin 5, even if the temperature rises, these key components will not be damaged or their performance will degrade due to overheating, thus ensuring the quality of the solidified electrode during manufacturing and its long-term operational reliability. Through this integration and solidification method, the small capacitor-driven solidified electrode can stably and reliably extract the required current and voltage signals and power supply in a medium-voltage power grid environment. This effectively solves the problems of low voltage withstand capability, poor temperature resistance, and incompatibility with the curing process in existing technologies, significantly improving the overall performance and service life of the equipment.

[0054] As one embodiment of this utility model, it also includes silicone rubber 6, which is coated on the outer layer of epoxy resin 5 for UV protection.

[0055] Silicone rubber 6 refers to an elastomer material with excellent weather resistance, UV resistance, ozone resistance, high and low temperature resistance, and good insulation properties. Specifically, silicone rubber 6 is configured to coat the outer layer of epoxy resin 5, forming a protective coating. The purpose is that silicone rubber 6 can effectively absorb or reflect ultraviolet rays, thereby preventing ultraviolet rays from directly acting on the surface of epoxy resin 5, avoiding degradation, embrittlement, or cracking of epoxy resin 5 due to long-term ultraviolet radiation, thus extending the service life of the sealed electrode and maintaining its stable insulation properties.

[0056] As one embodiment of this utility model, the current-voltage sensor group includes:

[0057] The incoming voltage sensor 7 has its high-voltage end connected to the incoming side of the medium-voltage power grid and its low-voltage end grounded.

[0058] The voltage sensor 8 is located on the outgoing side, with the high-voltage end connected to the conductive rod 4 and the low-voltage end grounded.

[0059] Zero-sequence current sensor 9 and phase current sensor 10 are sleeved on conductive rod 4;

[0060] Ceramic capacitors are integrated into the input-side voltage sensor 7 and the output-side voltage sensor 8.

[0061] The solution proposed in this application, by explicitly configuring the incoming-side voltage sensor 7, the outgoing-side voltage sensor 8, the zero-sequence current sensor 9, and the phase current sensor 10, can comprehensively monitor the operating parameters of the medium-voltage power grid. Specifically, the incoming-side voltage sensor 7 and the outgoing-side voltage sensor 8 are configured to acquire voltage information from the incoming and outgoing sides of the medium-voltage power grid in real time, thereby enabling monitoring of the grid's voltage stability and voltage drop caused by load changes. Simultaneously, the zero-sequence current sensor 9 and the phase current sensor 10 are mounted on the conductive rod 4, allowing for accurate detection of the phase current and zero-sequence current flowing through the conductive rod 4, which is crucial for overload protection, short-circuit protection, and ground fault detection. Furthermore, a ceramic capacitor is integrated into the incoming-side voltage sensor 7 and the outgoing-side voltage sensor 8. Its function is to divide the high-voltage signal, converting it into a low-voltage signal for subsequent signal processing circuitry to acquire and analyze, while providing necessary insulation and anti-interference capabilities to ensure stable and reliable operation of the sensors in harsh power grid environments.

[0062] As one embodiment of this utility model, the circuit connection of the current and voltage sensor group includes:

[0063] A current sensor sampling resistor connected in parallel with the zero-sequence current sensor 9 and the phase current sensor 10 is used to convert the current signal into a voltage signal;

[0064] The current and voltage sensor circuit board 11 is used to integrate signal conditioning circuitry and connect sampling resistor, input-side voltage sensor 7, and output-side voltage sensor 8.

[0065] The current sensor sampling resistor is a resistive device used to convert current signals into voltage signals. By connecting the current sensor sampling resistor in parallel, the current signals output by the zero-sequence current sensor 9 and the phase current sensor 10 can be sampled and converted into voltage signals for subsequent signal processing. The current-voltage sensor circuit board 11 integrates a signal conditioning circuit, which may include amplifiers, filters, and other circuits to condition the voltage signal output by the sampling resistor, such as amplification and filtering, to improve signal quality and accuracy. The current-voltage sensor circuit board 11 also connects the sampling resistor to the input-side voltage sensor 7 and the output-side voltage sensor 8, thereby achieving synchronous acquisition and processing of current and voltage signals.

[0066] The solution in this application converts the current signal into a voltage signal through the sampling resistor of the current sensor, and then conditions the voltage signal through the current-voltage sensor circuit board 11, thereby improving the measurement accuracy and stability of the current and voltage signals. Simultaneously, by integrating the signal conditioning circuit onto the current-voltage sensor circuit board 11, the size and weight of the system can be reduced, and the system's integration and reliability can be improved.

[0067] As one embodiment of the present invention, the current and voltage sensor group also includes a current and voltage sensor fixing member 12, which is used to fix the sensor assembly.

[0068] The current and voltage sensor mounting bracket 12 refers to the structural component used to fix sensor assemblies such as the incoming-side voltage sensor 7, the outgoing-side voltage sensor 8, the zero-sequence current sensor 9, and the phase current sensor 10. Specifically, the current and voltage sensor mounting bracket 12 can be made of various materials and structural forms; for example, it can be made of metal, plastic, or composite materials, and can be designed with various fixing methods such as snap-fit, bolt connection, or adhesive bonding. The design of the current and voltage sensor mounting bracket 12 needs to fully consider the size, shape, and installation position of the sensor assemblies to ensure that it can firmly fix the sensor assemblies without adversely affecting the measurement accuracy of the sensor assemblies.

[0069] In one embodiment of this utility model, the current and voltage sensor group outputs detection signals through the current and voltage sensor aviation socket.

[0070] Among them, the aviation connector for current and voltage sensors is a standardized connector used to establish a reliable electrical connection between current and voltage sensor arrays and external devices. Specifically, the aviation connector for current and voltage sensors can adopt a multi-core structure, with each core corresponding to a detection signal, such as a voltage signal, current signal, or temperature signal. The aviation connector for current and voltage sensors typically has a locking mechanism to prevent accidental disconnection and ensure the stability of signal transmission.

[0071] This application's solution utilizes an aviation socket for current and voltage sensors, enabling the standardized output of the sensor array's detection signals, thereby improving the reliability and stability of signal transmission. Furthermore, when the current and voltage sensor array needs replacement, simply plugging and unplugging the aviation socket eliminates the need for complex wiring operations, greatly simplifying the maintenance process.

[0072] As one embodiment of this utility model, the circuit topology of the capacitor-powered power supply group includes a first topology or a second topology.

[0073] The first topology is connected to the incoming side of the medium-voltage power grid via a conductor and is connected in parallel with the vacuum interrupter 1.

[0074] The second topology is connected to the end of the conductive rod 4 via a wire and is connected in parallel with the output voltage sensor 8.

[0075] The reason this application employs both a first topology and a second topology is to account for the different power extraction location and power performance requirements of various application scenarios. By providing two different topologies, the appropriate power extraction method can be flexibly selected according to actual needs, thereby better meeting the requirements of different application scenarios. Specifically, when power needs to be obtained from the incoming side of the power grid, the first topology can be selected; when power needs to be obtained from the outgoing side of the power grid, the second topology can be selected.

[0076] The first topology connects the capacitor-fed power supply in parallel with the vacuum interrupter 1, allowing the capacitor-fed power supply to extract energy independently of the vacuum interrupter 1's operating state. This means that even when the vacuum interrupter 1 is disconnected, the capacitor-fed power supply can still obtain power from the medium-voltage grid, thus ensuring the continuity and reliability of power supply. Furthermore, by adopting a parallel connection, the impact of the capacitor-fed power supply on the medium-voltage grid can be reduced, avoiding interference with the normal operation of the grid.

[0077] However, when using the first topology, it is connected to the incoming side of the medium-voltage power grid via a wire and is in parallel with the vacuum interrupter 1. This connection method may be affected by voltage fluctuations on the incoming side in certain application scenarios, thus affecting the stability and efficiency of power extraction. Therefore, this application proposes a second topology, in which the capacitor-powered power supply group is connected to the end of the conductive rod 4 via a wire and is in parallel with the output voltage sensor 8, thereby effectively solving the above problems. By connecting the capacitor-powered power supply group in parallel with the output voltage sensor 8, the second topology can effectively utilize the output voltage signal for power extraction, thereby avoiding the impact of incoming voltage fluctuations on power extraction and improving the stability and efficiency of power extraction. In addition, since the output voltage is relatively stable, the size and cost of the capacitor-powered power supply group can be reduced, making it more suitable for applications of miniaturized solid-sealed poles.

[0078] As one embodiment of this utility model, the capacitor-powered power supply outputs power through an aviation socket, and the power extraction position can be selected from the incoming or outgoing side.

[0079] This application's solution, by incorporating an aviation socket, allows the power source location of the capacitor-powered power supply to be flexible, no longer limited to a single location, but rather flexibly selected from either the incoming or outgoing line side according to actual needs. This flexibility enables the solution to adapt to more application scenarios, improving the versatility of the capacitor-powered power supply.

[0080] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope. All such changes and modifications fall within the scope of protection claimed by this utility model, which is defined by the appended claims and their equivalents.

Claims

1. A small capacitor-driven solid-sealed terminal block, applied to medium-voltage power grids, for extracting current and voltage signals and power supply from the medium-voltage power grid, characterized in that... include: Vacuum interrupter (1), the input end of which is connected to the incoming line side of the medium voltage power grid; The transition piece (2) and the spring contact finger (3) are movably connected to the output end of the vacuum interrupter (1); The conductive rod (4) is connected to the spring contact finger (3) and extends to the output side of the medium voltage power grid. The spring contact finger (3) is used to realize the electrical connection between the transition piece (2) and the conductive rod (4). Current and voltage sensor arrays are used to monitor the operating parameters of medium-voltage power grids; A capacitor-powered power supply group is disposed inside the solid-sealed pole. The capacitor-powered power supply group includes a capacitor bank composed of multiple ceramic capacitors connected in series and a transformer electrically connected to the capacitor bank. Epoxy resin (5) is used to encapsulate the vacuum interrupter (1), transition piece (2), spring contact finger (3), conductive rod (4), current and voltage sensor group and capacitor power supply group inside the encapsulated pole. The capacitor bank formed by multiple ceramic capacitors connected in series and the transformer have temperature resistance properties that match the curing temperature of the epoxy resin (5) body.

2. The small capacitor power extraction solid-sealed terminal according to claim 1, characterized in that, It also includes silicone rubber (6), which is coated on the outer layer of epoxy resin (5) for UV protection.

3. The small capacitor power extraction solid-sealed terminal according to claim 1, characterized in that, The current and voltage sensor group includes: The incoming voltage sensor (7) has its high-voltage end connected to the incoming side of the medium-voltage power grid and its low-voltage end grounded. The voltage sensor (8) on the outgoing side is connected to the conductive rod (4) at the high-voltage end and grounded at the low-voltage end; Zero-sequence current sensor (9) and phase current sensor (10) are sleeved on conductive rod (4); Ceramic capacitors are integrated into the input voltage sensor (7) and the output voltage sensor (8).

4. The small capacitor power extraction solid-sealed terminal according to claim 3, characterized in that, The circuit connection of the current and voltage sensor group includes: The current sensor sampling resistor connected in parallel with the zero-sequence current sensor (9) and the phase current sensor (10) is used to convert the current signal into a voltage signal; The current and voltage sensor circuit board (11) is used to integrate the signal conditioning circuit and connect the sampling resistor, the input voltage sensor (7), and the output voltage sensor (8).

5. The small capacitor power extraction solid-sealed terminal according to claim 3, characterized in that, The current and voltage sensor group also includes a current and voltage sensor fixture (12) for fixing the sensor assembly.

6. The small capacitor power extraction solid-sealed terminal according to claim 5, characterized in that, The current and voltage sensor group outputs detection signals through the current and voltage sensor aviation socket.

7. The small capacitor power extraction solid-sealed terminal according to claim 1, characterized in that, The circuit topology of the capacitor-powered power supply group includes either a first topology or a second topology.

8. The small capacitor power extraction solid-sealed terminal according to claim 7, characterized in that, The first topology is connected to the incoming side of the medium-voltage power grid via a conductor and is connected in parallel with the vacuum interrupter (1).

9. The small capacitor power extraction solid-sealed terminal according to claim 7, characterized in that, The second topology is connected to the end of the conductive rod (4) by a wire and is connected in parallel with the output voltage sensor (8).

10. The small capacitor power extraction solid-sealed terminal according to claim 7, characterized in that, The capacitor-powered power supply outputs power through an aviation socket, and the power source can be selected from the incoming or outgoing side.

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