MV/LV modular and compact equipment: specific solutions to all requirements

The medium voltage switchgear of secondary distribution substations is the interface between the MV network and consumers. It must ensure continuity of supply in optimum conditions. Technological development of the switchgear has followed the evolution of requirements such as safety of personnel and reliability of equipment. Thus conventional open type equipment is replaced by metal enclosed switchboards. The use of SF₆ gas as an insulating and arc quenching medium is an important factor in this evolution. Subsequent stages led to a certain specialisation according to the application. Thus modular switchgear brought its adaptability to complex and changeable schemes for distribution in industry, whereas compact, nonextensible switchgear, less flexible, but more impervious to climatic conditions due to higher insulation levels, is preferred for public distribution. The authors discuss how these two systems complement each other