OCEM and ENEA gained a wide experience in the design and experimental characterization of fast and accurate switching systems for high DC currents, as required to control magnets and superconductors. The exploited idea consists in inserting an electronic switch in parallel to a fast electromechanical switch in air, to combine the benefits of both devices. The electronic switch is turned on and off to support the electromechanical commutations, reducing the jitter to tens microseconds and limiting the arcs that would reduce the system lifetime. During the performed tests, DC currents up to 20 kA were diverted in less than 100 µs with good repeatability. In case of emergency, the current can be interrupted in few tens of milliseconds. If necessary, a resistor can be inserted in parallel to the switch to dissipate the energy trapped in inductive loads or to produce desired overvoltages (a voltage up to 5 kV was reached in this configuration). Specific circuits were designed to preserve the components from transient voltage overshoots. This switching system is expected to work for 10000 operations without major maintenance. The developed solutions may be extended to many relevant applications as particle accelerators and HVDC networks. Copyright © 2017 CC-BY-3.0 and by the respective authors
Switching network units for high currents and voltages or plasma applications
Zito, P.;Lampasi, A.
2016-01-01
Abstract
OCEM and ENEA gained a wide experience in the design and experimental characterization of fast and accurate switching systems for high DC currents, as required to control magnets and superconductors. The exploited idea consists in inserting an electronic switch in parallel to a fast electromechanical switch in air, to combine the benefits of both devices. The electronic switch is turned on and off to support the electromechanical commutations, reducing the jitter to tens microseconds and limiting the arcs that would reduce the system lifetime. During the performed tests, DC currents up to 20 kA were diverted in less than 100 µs with good repeatability. In case of emergency, the current can be interrupted in few tens of milliseconds. If necessary, a resistor can be inserted in parallel to the switch to dissipate the energy trapped in inductive loads or to produce desired overvoltages (a voltage up to 5 kV was reached in this configuration). Specific circuits were designed to preserve the components from transient voltage overshoots. This switching system is expected to work for 10000 operations without major maintenance. The developed solutions may be extended to many relevant applications as particle accelerators and HVDC networks. Copyright © 2017 CC-BY-3.0 and by the respective authorsI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
