The development of power capacitor manufacturing industry began in the 1950s and has been developing for more than 50 years. In general, China''s power capacitor development history can be divided into three stages.
     The first stage, before the 20th century, 70 years, basically to the capacitor paper as a solid medium to mineral oil or PCB as a liquid medium.
     In the second stage, from the beginning of the 1970s, the polypropylene film and the capacitor paper composite dielectric capacitor replaced the whole paper capacitor, which was made of dodecylbenzene, silicone oil, diarylethane, isopropyl-1-based biphenyl medium. The use of these new media, the film composite dielectric capacitor loss is only 1/3 of the total paper capacitors, about 0.8 ~ 1.5W / kvar. Product heat problems have been improved, a single capacity increased nearly 20 times. At the same time, due to the new liquid medium has a good suction performance, so that the capacitor running and failure when the shell expansion burst 1 greatly reduced the possibility of greatly improving the reliability of the safe operation of the grid.
     Phase 3, from the early 80s, full-film capacitors gradually replace the film composite media products. It is a polypropylene film as a solid medium, with diarylethane, benzyl toluene or SAS-70 as a liquid medium, a single capacity of the capacitor reaches 334-1000kvar, the capacitor loss is reduced to 0.1-0.2W / kvar, reliability Has been greatly improved.

     China''s power capacitors are currently the main varieties of high and low voltage shunt capacitors and complete sets of devices, filter capacitors and complete sets of devices, electric capacitors, coupling capacitors and capacitive voltage transformers, laboratory capacitors and complete sets of equipment. Among them, high and low voltage shunt capacitors and complete sets of equipment, including self-healing capacitors, high voltage shunt capacitors, assembled capacitors and complete sets of devices.

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