What problems will be produced when the capacitor is used?
The capacitor is a complicated thing, because it is composed of many elements, due to raw materials and manufacturing process, it is easy to have a lot of small impurities, factory production of capacitor medium mechanical damage, pinhole, problem of low cleanliness.
The early damage of capacitor is mainly due to the reason of manufacturing. High voltage capacitor: usually consisting of a plurality of elements composed of each element by Shen, Al foil as electrode, the solid medium is placed between electrodes made of winding. Elements of the plate area is large, due to raw materials and manufacturing processes and other reasons, there may be impurities in the medium, mechanical damage. In the system caused by a variety of causes over voltage, over current and around the high, low temperature effect, these weak points will cause dielectric breakdown. Breakdown will usually produce sparks, further expand the scope, thereby forming a multi - layer short circuit and even the entire element. With the breakdown voltage will series component on the increase, and its parallel components will be shortened, so that the rest of the group on the increase of series voltage, current flowing through each element increases. Will lead to rapid aging of components, increase the calorific value. At the same time in partial discharge under high voltage there will also be a plate edge. In addition to the breakdown point, the impregnant released large amounts of gas, after a certain period of time, and the whole series fault series other components will have breakdown, and there will be a series of new short circuit. The series number is further reduced, further improve the voltage, the current phenomenon is more serious, medium worse, the increase in temperature, thereby increasing the arc, impregnation will further release gases, and so on, the damage of components is more and more, more and more serious housing expansion. In this case, the fuse protection relay protection fault capacitor will be timely removed, if not removed. Further breakdown will form a strong arc in the housing, other parallel capacitor and the energy surge of people, will be in a very short period of time so that the capacitor medium rapidly aging, resulting in expansion, expansion tank in severe cases, will explode. This accident can not be eliminated for users, it belongs to the early damage of the capacitor, the cycle is usually about a year. Only manufacturers try to improve product quality, strengthen the detection means, in order to reduce the early damage rate. Therefore, in the choice of compensation capacitors, the conditions of the unit should be as far as possible to choose a reliable performance of the collection, self-healing capacitor.
