How does the aluminum foil protruding folding structure of High Voltage Shunt Capacitor optimize the electric field distribution and improve the electrical performance? ​

Basic principles of folding and lead-out process ​
In the manufacture of High Voltage Shunt Capacitor components, two aluminum foils are usually sandwiched between multiple layers of solid dielectrics for winding to form a basic structure. For components with aluminum foil protruding folding structure, the key folding process is immediately carried out after the winding process is completed. The specific operation is to protrude the two aluminum foils out of the solid dielectric layer on one side and fold the other side inward so that they are within the edge of the solid dielectric layer. This unique folding design breaks the traditional aluminum foil arrangement method and lays the foundation for subsequent performance improvement. ​
Unlike conventional components that require lead sheets to be inserted to achieve current transmission, components with aluminum foil protruding folding structure directly use the protruding aluminum foil to lead out and import current. This change in the current lead-out method seems simple, but it actually contains in-depth considerations of electric field distribution and current transmission characteristics. The use of traditional lead sheets will inevitably produce burrs and sharp corners on the edge of the component. These irregular shapes will cause local electric field concentration and have a negative impact on the electrical performance of the capacitor. The components with aluminum foil protruding folding structure eliminate the problems caused by lead sheets from the root by cleverly using the aluminum foil itself for current transmission. ​
Optimization of electric field distribution by folding and lead-out process​
During the operation of high-voltage parallel capacitors, the uniformity of electric field distribution is crucial. If there are burrs and sharp corners on the aluminum foil and lead sheets at the edge of the component, areas with excessively high local electric field strength will be formed. These areas are like weak points in electrical performance and are prone to partial discharge. When the local electric field strength exceeds the tolerance of the medium, partial discharge will occur. Over time, the continuous development of partial discharge may lead to the gradual deterioration of the medium, and eventually cause the breakdown failure of the capacitor, seriously affecting the normal operation and service life of the capacitor. ​
The folding and lead-out process of the aluminum foil protruding folding structure effectively improves this situation through special folding treatment of the aluminum foil. One side of the aluminum foil is protruded outside the solid dielectric layer, and the other side is folded inward, so that the edge of the aluminum foil and the solid dielectric layer are more smoothly combined, reducing the electric field distortion at the edge. At the same time, since the lead sheet is no longer used, the interference of the lead sheet burrs and sharp corners on the electric field distribution is avoided, making the electric field distribution of the entire component more uniform. This uniform electric field distribution reduces the risk of excessive local electric field intensity, improves the ability of the component to resist local discharge, and provides a guarantee for the stable operation of the capacitor. ​
Improvement of electrical performance by folding and lead-out process​
The local discharge starting voltage, extinction voltage and breakdown voltage of the component are important indicators for measuring the electrical performance of high-voltage parallel capacitors. The local discharge starting voltage refers to the voltage value when the component starts to discharge locally, the extinction voltage refers to the voltage value when the local discharge stops, and the breakdown voltage is the voltage value when the insulation of the component is destroyed. The higher these three voltage values ​​are, the better the electrical performance of the component is, and it can withstand higher working voltages and harsher working environments.​
The folding and lead-out process of the aluminum foil protruding folding structure significantly improves the local discharge starting voltage, extinction voltage and breakdown voltage of the component due to the optimization of the electric field distribution. When the component is subjected to voltage during operation, the uniform electric field distribution allows the voltage to be more reasonably distributed over the entire component, rather than concentrated on certain weak points. This means that the component requires a higher voltage to start partial discharge, and after partial discharge occurs, a higher voltage is also required to maintain the discharge state, thereby increasing the partial discharge extinction voltage. At the same time, a more uniform electric field distribution reduces the risk of the insulating medium being broken down due to local electric field concentration and increases the breakdown voltage. These performance improvements enable the high-voltage shunt capacitors using this process to operate stably at higher voltage levels and adapt to more complex power system environments. ​
Reliability guarantee of current lead-out in the folding and lead-out process​
During the operation of high-voltage shunt capacitors, the stable transmission of current is the basis for their normal operation. Although the components of the aluminum foil protruding folding structure optimize the electric field distribution through a unique design, the reliability of the aluminum foil connection with the outside still needs to be ensured in the current lead-out link. To achieve this goal, special welding or crimping processes are used in the manufacturing process. ​
The welding process fuses the aluminum foil with the external connecting conductor through high temperature to form a strong electrical connection. During the welding process, parameters such as welding temperature, time and pressure need to be precisely controlled to ensure the quality of the welding point. The appropriate welding temperature can fully fuse the aluminum foil and the connecting conductor, while avoiding overheating and deformation of the aluminum foil or degradation of its performance due to excessive temperature. Accurate welding time and pressure control can ensure the strength and conductivity of the welding point and prevent problems such as cold welding and desoldering. ​
The crimping process is to tightly press the aluminum foil and the connecting conductor together through mechanical pressure. This process uses a special crimping die to apply uniform pressure to the aluminum foil and the connecting conductor to form a good electrical contact between the two. The advantage of the crimping process is that it can avoid the influence of high temperature that may occur during the welding process on the performance of the aluminum foil, and the crimping point has high reliability and can withstand large currents and mechanical stresses. Both the welding process and the crimping process have been verified by a large number of experiments and practices to ensure that the connection between the aluminum foil and the outside can be stable and reliable under various working conditions to ensure the normal transmission of current.​
Performance of folding and lead-out process in practical application​
In actual power engineering applications, high-voltage parallel capacitors using aluminum foil protruding folding structure folding and lead-out process have shown excellent performance. In some industrial places with high requirements for power quality, such as precision electronic manufacturing enterprises, the stability of the power system directly affects the quality and production efficiency of products. During the operation of traditional high-voltage parallel capacitors, due to problems such as partial discharge, they may interfere with the power system and affect the normal operation of the equipment. The capacitors using this process, with their optimized electric field distribution and improved electrical performance, effectively reduce the occurrence of partial discharge, reduce interference to the power system, and provide reliable power guarantee for the stable production of enterprises. ​
In high-voltage transmission lines, the voltage level is high and the environment is complex, and the performance requirements for high-voltage parallel capacitors are more stringent. The capacitors using aluminum foil protruding folding structure folding and lead-out process can maintain a stable operating state under high voltage environment. Its higher partial discharge starting voltage, extinction voltage and breakdown voltage enable it to better resist voltage fluctuations and shocks, ensure the reactive power compensation effect of the transmission line, improve the transmission efficiency, and reduce line losses.​
Technical development and future prospects of folding and lead-out process​
With the continuous development of power technology, the requirements for the performance of high-voltage parallel capacitors are also increasing. The folding and lead-out process of the aluminum foil protruding folding structure is also constantly innovating and improving. In terms of materials, new aluminum foil materials and solid dielectric materials are constantly emerging. These materials have better electrical and physical properties. Combined with the folding and lead-out process, they can further improve the performance of capacitors. For example, aluminum foil materials with higher purity and more uniform organizational structure can make current transmission more stable and reduce resistance loss; solid dielectric materials with better performance can withstand higher electric field strength and improve the withstand voltage of capacitors. ​
In terms of technology, automation and intelligent technology are gradually applied to the production process of folding and lead-out process. Automated equipment can more accurately control the angle, length and welding or crimping parameters of folding and current lead-out, improve production efficiency and consistency of product quality. Intelligent detection technology can monitor various parameters in the production process in real time, discover and solve potential problems in time, and ensure that every production link meets high standards. In the future, with the continuous advancement of technology, the folding and lead-out process of the aluminum foil protruding folding structure is expected to be applied in more fields, providing stronger technical support for the development of the power system.