Recent Technical Trends of Vacuum Circuit-Breakers (VCBs)

摘要

Since the early era of the wider acceptance of Vacuum Circuit-Breakers (VCBs) in the 1960s, we have consistently continued its own development of VCBs as a core product of current breaking technologies. In the 1970s, we were one of the earliest companies to realize higher system voltages for the VCBs. We successfully produced an 84kV single-break VCB and a 168kV double-break VCB. Following the advent of new electrode materials (Cu-Cr type) and the development of the axial magnetic field electrodes with outstanding current breaking capabilities in the 1980s and the adoption of ceramic insulating envelopes in the latter half of the 1990s, we achieved the compact design of Vacuum Interrupters (VIs) and increased VI capacities. After that, we successfully realized the reduction of overall VCB unit size. In 2000 and thereafter, we have made efforts to manufacture eco-friendly switchgears without using SF_6 gas, which is a greenhouse gas. We also intend to develop our own technologies and products meeting the requirements of our customers, such as the reduction of life cycle cost.