Transverse-Field Vacuum Interrupter. Volume 1. Development of a Metallic Return-Transfer Breaker

摘要

A novel high-voltage dc breaker designed for the Bonneville Power Administrtion (BPA) and installed by BPA at its Celilo, Oregon converter station has been shown in field trials to be capable of interrupting up to 1700-A dc against a recovery voltage of 80 kV. The breaker, which is known as a Metallic Return Transfer Breaker (MRTB), changes the mode of operation of the Pacific Intertie (+- 400 kV dc, 850 miles long) from monopolar ground return to monopolar metallic return without deenergizing the dc system. MRTB combines two technologies: the first is a prototype 72-kV vacuum interrupter developed by Westinghouse R and D; the other is a vacuum arc current limiter prototype device developed under an ongoing EPRI contract RP564-1 and -2. The two are connected in series, with a 10- mu F capacitor in parallel with the series connected devices. The MRTB can switch dc currents up to 2.5 kA against a recovery voltage of 85 kV. Advantages of the technique used in this breaker design are insensitivity to circuit current polarity and isolation of the current-zero-producing magnetic field from circuit potential. (ERA citation 08:029529)