Discussion on “The change-over of low-tension distribution systems from direct current to alternating current” before the Institution, 31st March, 1932

The vast majority of distribution systems currently in use, work with alternating current at 50 Hz or 60 Hz. Several of the distributed resources (generators or storage) supply electrical energy in the form of direct current. Also, there are continuous end-use applications such as centralized variable speed drives, and the rapidly growing application in electric cars which has recently started. This panorama leads to the growing interest in the application of fuses in direct current systems, not as an adaptation of the alternating current fuse but as a specific design. The article presents the crucial differences between direct and alternating circuits, oriented to the operation of the fuse, highlighting their advantages and disadvantages, citing the complications in the design that are required for this growing application. The continuous operation of the fuse is explained in its three fundamental parts: pre-arc, arc and post-arc. The most important current applications are analyzed, such as the protection of: circuits with batteries, circuits of electric vehicles for individual use, power electronics, photovoltaic cells, public transport and circuits in mining. It is concluded in the need to deepen the study of these applications in order to achieve specific fuses designs for direct current and not mere adaptations of the traditional alternating current fuse designs.

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Comparison of alternating current with direct current electroshock across the closed chest

The American Journal of Cardiology ◽

10.1016/0002-9149(62)90299-0 ◽

1962 ◽

Vol 10 (2) ◽

pp. 223-233 ◽

Cited By ~ 216

Author(s):

Bernard Lown ◽

Jose Neuman ◽

Raghavan Amarasingham ◽

Barouh V. Berkovits

Keyword(s):

Direct Current ◽

Alternating Current ◽

Closed Chest

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CONCEPTS OF ELECTRONICALLY-CONTROLLED ELECTROMECHANICAL/MECHANOELECTRICAL STEER-, AUTODRIVE- AND AUTOABSORBABLE WHEELS FOR ENVIRONMENTALLY-FRIENDLY TRI-MODE SUPERCARS

Journal of Circuits System and Computers ◽

10.1142/s0218126694000296 ◽

1994 ◽

Vol 04 (04) ◽

pp. 501-516 ◽

Cited By ~ 8

Author(s):

BOGDAN T. FIJALKOWSKI ◽

JAN W. KROSNICKI

Keyword(s):

Direct Current ◽

Integrated Circuit ◽

Environmentally Friendly ◽

Alternating Current ◽

Switching Frequency ◽

Neuro Fuzzy ◽

Interior Permanent Magnet ◽

Application Specific Integrated Circuit ◽

Computer Processor ◽

Application Specific

Concepts of the electronically-controlled electromechanical/mechanoelectrical Steer-, Autodrive- and Autoabsorbable Wheels (SA2W) with their brushless Alternating Current-to-Alternating Current (AC-AC), Alternating Current-to-Direct Current-Alternating Current (AC-DC-AC) and/or Direct Current-to-Alternating Current (DC-AC)/Alternating Current-to-Direct Current (AC-DC) macroelectronic converter commutator (macro-commutator) wheel-hub motors/generators with the Application Specific Integrated Matrixer (ASIM) macroelectronic converter commutators (ASIM macrocommutators) and Application Specific Integrated Circuit (ASIC) microelectronic Neuro-Fuzzy (NF) computer (processor) controllers (ASIC NF microcontrollers) for environmentally-friendly tri-mode supercars (advanced ultralight hybrids) have been conceived by the first author and designed by both authors with the Cracow University of Technology’s Automotive Mechatronics Research and Development (R&D) Team. These electromechanical/mechanoelectrical wheel-hub motors/generators, respectively, for instance, can be composed of the outer rotor with the Interior Permanent Magnet (IPM) poles and the inner stator that has the three-phase armature winding. The macroelectronic converter commutator establishes the AC-AC cycloconverter, AC-DC rectifier-DC-AC inverter and/or DC-AC inverter/AC-DC rectifier ASIM macrocommutator. The microelectronic NF computer (processor) controller establishes the ASIC microcomputer-based NF microcontroller. By adopting continuous semiconductor bipolar electrical valves in the high-power ASIM, it has been able to increase the commutation (switching) frequency and reduce harmonic losses of the electromechanical/mechanoelectrical wheel-hub motors/generators, respectively.

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