Capacitive voltage divider aluminum foil lead sheet crimp type series connection

作者： GOZ Electric 时间：2014-04-28 10:59:11 阅读：16

    My country's capacitor industry began to use aluminum foil lead sheets at the end of the 20th century, replacing copper foil lead sheets with aluminum foil that is slightly narrower than the component width. The thickness of the aluminum foil lead sheet is about 0.05~0.10 mm. During the component winding process, the lead sheets are placed in the component in advance, and the component winding adopts a hidden foil structure. The lead-out ends can be led from both ends of the component or from one end of the component. Considering the convenience of the rolling process, the lead-out terminal is usually led from one end of the component. The lead sheets are isolated with insulating pads. Before pressing, fold the leads of the two aluminum foils up and down from the end of the component to the two large surfaces above and below the component, and then connect them to the leads of the aluminum foil lead sheets of the adjacent components. Stick together tightly. Implement series connection between components. The components and cores of this structure have simple processing technology. The connection is reliable. This structure avoids quality defects that may be caused by manual welding of copper foil lead sheets, improves the operational reliability of the capacitor voltage divider, and effectively improves production efficiency. It has been widely used in the capacitor industry in recent years. Aluminum foil lead sheets replace copper foil lead sheets, which reduces material and processing costs, but does not fundamentally change the damage that sharp corner burrs on the lead sheet edges may cause to the media.

     The leadless series soldering structure adopts aluminum foil protrusion welding technology. Directly solder the protruding aluminum foil electrodes of adjacent components together left and right alternately. This structure avoids the damage to the medium caused by the lead plate connection structure and the edge effect and compression effect. It is a leap forward in the connection structure of primary capacitor voltage divider components. After adopting this structure, the average electric field strength of the capacitive voltage divider can be appropriately increased. Moreover, the capacitive voltage divider with this structure can use the advanced automated production process of parallel capacitors to improve production efficiency and simplify the production process. It should be noted that this type of connection structure is prone to quality defects such as virtual welding and damage during the series welding of the plates. Especially when the capacitance of the voltage dividing capacitor component is very small and the component is thin. It will bring difficulties to series welding. It is believed that with the advancement of the core welding process of capacitor products, the lead-less aluminum foil protruding welding structure will have a large application space.

     In recent years, a series connection method of components with no lead structure has been adopted in some foreign high-voltage capacitor products, which gives people a refreshing feeling. The plate adopts a hidden foil structure. After the element is wound, the ends of the two aluminum foil plates are exposed on the upper and lower surfaces of the element respectively. The adjacent elements are pressed tightly against each other to realize the series connection of the elements. On the advanced automated production line, winding, testing, stacking, pressing, packaging and other tasks can be realized at one time. Some use aluminum foil spot welding to enhance the reliability of series connection points.

     This structure greatly simplifies the production process, the idea is simple, and it is very suitable for automated production. The production efficiency of components and cores is high, and the dispersion of each process of core production is reduced. Effectively improve product quality. At present, domestic manufacturers are trying to develop fully automatic production lines, which are based on this leadless structure capacitor voltage divider. Domestic products using this new structure have more than 3 years of successful operation experience. When this connection structure is used in CVT capacitive voltage dividers or coupling capacitors, it will cause high-frequency equivalent series resistance and high-frequency capacitance to be larger, but it still meets the requirements of relevant standards. Of course, communication technology has undergone fundamental changes now. Power carriers are being replaced by optical cable communication technology. High-frequency resistance and capacitance are no longer meaningful parameters. In the long term, with the advancement of capacitive voltage divider process technology. This leadless sheet crimped series structure will eventually become the development direction of lead structures for capacitive voltage divider components.

     The connection method of the leadless crimping series structure makes the automated production of capacitive voltage dividers possible, which will greatly improve production efficiency. Some capacitive voltage dividers require a small inherent inductance. In this case, aluminum foil protrusion welding of components for electrical connection will provide better results. Of course, each connection method has its own characteristics. Each manufacturer has summed up a lot of experience in the connection structures they adopt, and they also have their own unique features. Therefore, the appropriate structure can be selected according to its process characteristics.