Speaker
Maksim Manzuk
(Joint Stock Company "D.V. Efremov Institute of Electrophysical Apparatus")
Description
High current DC switches play a very important role in the ITER coil power supply system (CPSS) being key components of its two major parts: switching network units (SNU) for plasma initiation and fast discharge units (FDU) for superconducting coils energy extraction in case of quench. For both functions, circuit-breakers rated up to 70 kA steady-state current and 10 kV voltage are required to transfer the coil current into discharge resistors. Besides, make switches with similar ratings will be used in SNUs to reduce the resistance and, hence, the loop voltage during plasma initiation. Moreover, make switches are required for protection of CPSS components.
Two groups of switches were developed in Efremov Institute for the ITER project. The first group involves three types of devices with considerable lifetime: open, make and disconnect switches with similar design and ratings, which are intended for SNU. The second group comprises two very reliable explosively actuated switches (circuit breaker and make switch), that will be used as back-up protective devices in FDU. Being mechanical devices, all these switches are characterised by extremely fast operation: 2-4 ms for SNU switches and less than 1 ms for FDU back-up switches.
After a short description of switch design, the paper focuses on the procedure and results of type tests on full-scale prototypes, which were manufactured after completion of the preliminary design at the beginning of 2012. The test program that was implemented in 2013-2015, among a number of electrical, hydraulic and functional tests, included life-time tests with rated currents, mechanical endurance tests for SNU switches and reliability tests for backup circuit-breaker.
The successful results of the type tests confirmed the suitability of switch design and compliance with ITER requirements and made it possible to start manufacturing of the switches for delivery to the ITER Site.
Co-authors
Alexander Roshal
(Joint Stock Company "D.V. Efremov Institute of Electrophysical Apparatus", Doroga na Metallostroy, 3, 196641 St. Petersburg, Russia, Russian Federation)
Francesco Milani
(ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex, France, France)
Inho Song
(ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex, France, France)
Jacques Chiron
(ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex, France, France)
Konstantin Bestuzhev
(Joint Stock Company "D.V. Efremov Institute of Electrophysical Apparatus", Doroga na Metallostroy, 3, 196641 St. Petersburg, Russia, Russian Federation)
Maksim Manzuk
(Joint Stock Company "D.V. Efremov Institute of Electrophysical Apparatus", Doroga na Metallostroy, 3, 196641 St. Petersburg, Russia, Russian Federation)
Sergey Miklyaev
(Institution "Project Center ITER", Sq. Academician Kurchatov, 1, bld.3, Moscow, 196641, Russia, Russian Federation)
