200-kA 650-kV pulsed current remote-control mechanical short-circuit switch for electrophysical facilities

A mechanical short-circuit (MSC) switch with remote control, which can be i nstalled into a high-current circuit between a capacitor bank and load, is described. The device enables the short-circuit of the load conductors to p rotect the load from accidental spontaneous discharge during the bank charg ing. Upon attaining a preset voltage across the bank, the MSC switch remove s the short from the load circuit within similar to 1 s on command to ensur e controlled discharge of the bank. The MSC switch has a pneumatic (air, 1 MPa) plunger drive shifting a current-carrying contact rod. The design and operation of the MSC switch for a system with coaxial conductors are descri bed. The device was tested in a short-circuit cycle regime with the short-c ircuit current amplitudes 80, 160, and 200 kA. In the open state, the MSC s witch with a transformer-oil-filled radial gap of 64.5 mm between coaxial e lectrodes has a pulsed electric strength of 650 kV. The working life of the MSC switch exceeds 600 cycles in the high-current operation regime and 150 0 in the zero-current mode. The device performance is illustrated by the re sults of testing three MSC switches in the chains between 500-kV Marx gener ators and their loads.