@ARTICLE{Bartosik_Marek_Ultra-fast_2021, author={Bartosik, Marek and Borkowski, Piotr and Wójcik, Franciszek}, volume={69}, number={2}, journal={Bulletin of the Polish Academy of Sciences Technical Sciences}, pages={e136743}, howpublished={online}, year={2021}, abstract={The article presents a new generation of ultra-fast hybrid switching systems (USH) for reliable, ultra-fast protection of various medium and low voltage DC systems (MVDC and LVDC). The DC switch-off takes place in a vacuum chamber (VC) cooperating with a semiconductor module using current commutation of natural or forced type. Against the background of the current state of science and technology, the paper depicts the basic scopes of USH applications and their particular suitability for operation in high magnetic energy DC circuits. In the case of DC system failures, this magnetic energy should be dissipated outside the system as soon as possible. Usually, magnetic blow-out switches (MBOS) with relatively low operating speed are used for this purpose. The article describes the theoretical basis and principles of construction of two types of novel USH systems: a direct current switching system (DCSS) and a direct current ultra-fast hybrid modular switch (DCU-HM). The DCSS family is designed for quench protection of superconducting electromagnets’ coils in all areas of application. The DCU-HM family is designed for the protection of all systems or vehicles of DC electrical traction and for related industrial applications. The conducted comparative analysis of the effectiveness of USH with respect to MBOS shows clear technical advantages of the new generation switching systems over MBOS. List of abbreviations used in the article is provided at the end.}, type={Article}, title={Ultra-fast hybrid systems for protecting direct current circuits with high magnetic energy}, URL={http://www.czasopisma.pan.pl/Content/119427/PDF/20_02065_Bpast.No.69(2)_26.04.21_K2_A_OK.pdf}, doi={10.24425/bpasts.2021.136743}, keywords={DC, direct current, superconducting coils, quench, electromagnets protection, DC switches, ultra-fast switches, hybrid switches, vacuum switches, DC electric traction}, }