Example of Installations of Disconnecting Circuit Breakers
Technical development of circuit breakers (CB) has made maintenance of them less frequent, while maintenance of open-air disconnectors (DS) for air insulated substations (AIS) is still normally required with rather short time intervals. The primary contacts of open-air DS are exposed to atmospheric and sometimes also industrial pollution, which require maintenance and related unavailability of adjacent circuits. The disconnecting circuit breaker (DCB) for AIS substations was introduced in 2000 in order to make use of the higher availability of CB’s and at the same time overcome the drawbacks with open-air DS’s. The DCB presented performs both the breaking function of CB’s and the disconnecting function of DS’s, using the same SF6 encapsulated contact(s). This integration of dual functions into the DCB makes it possible to build AIS without any open-air DS’s. Having all primary contacts encapsulated in SF6 and protected from industrial and atmospheric pollution, enable a major decrease of maintenance work and increase reliability of the primary system thus improving the overall substation availability. By using DCB’s, the space requirement is reduced to about half compared to traditional AIS using CB’s + DS’s. This will make rehabilitation of existing substations much easier and minimize environmental impact when building a new substation. Increase of availability and reduction of maintenance will give lower maintenance and outage cost during the service life of a substation. In addition, the investment cost for an AIS using DCB’s is less than for a solution with CB’s + DS’s. Using solutions with DCB will thus give asset owners a considerable reduction of Life Cycle Cost (LCC) of substations. Since 2000 the DCB concept has been applied in several transmission and sub-transmission substations in various countries, and at rated voltages from 72 to 420 kV. Up till now about 550 threephase DCB units have been sold. The main reasons for selecting the DCB concept instead of traditional CB+DS solutions are system reliability and availability, maintenance aspects, space requirements, ease of rehabilitation work and life cycle costs. In this paper, examples of DCB based substations are presented.
Disconnecting circuit breaker minimizing outage LCC availability space renewal substation
C-E S(O)LVER M N OLOFSSON
ABB Power Technologies SWEDEN ABB (China) Ltd CHINA
国际会议
广州
英文
2007-11-10（万方平台首次上网日期，不代表论文的发表时间）