High voltage

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Technically used electrical voltages in the upper high voltage range are referred to as maximum voltage. In electrical power engineering in Germany, the voltage levels 220 kV and 380 kV are part of the maximum voltage. Outside of the electrical networks, voltages of 300  kV (300,000 volts) or more are referred to as maximum voltage, although no uniform limit value has been specified. The concept of maximum voltage is not considered independently within standards and specifications for system safety. There this voltage level is included in the high voltage range , which includes all voltages above 1 kV. The highest possible voltages are selected in order to minimize transmission losses over long transport routes.

Applications

Energy transfer

Extra high voltage is used in the form of alternating voltage in the supra-regional line level of extensive power networks , the so-called transport network level , and is used in interconnected networks for the exchange and trading of electrical energy . Usual voltages, the effective values ​​of the line-to- line voltage are given, are 220 kV and 380 kV (400 kV) in Europe and 750 kV in parts of Russia. The Canadian Hydro-Québec operates an extensive high voltage network with 735 kV.

The DC voltage used is maximum voltage of up to ± 1100 kV (2.2 MV), as is the case with the Chinese HVDC Changji / Guquan . Those transmission techniques as high-voltage direct current designated abbreviated HVDC or UHVDC for English ultra high voltage direct current .

Physical experiments

Very high voltage occurs in some physical experiments, such as linear accelerators like the Van de Graaff accelerator .

generation

Very high voltages in the field of electrical energy technology are obtained from the lower voltages of the electrical generators using power transformers in power plants . Due to their design, electrical generators cannot generate maximum voltages, which is why the low generator voltage, a few kV up to a few 10 kV, is transformed into maximum voltage using nearby machine transformers.

In addition, they are used in the field of high voltage tests and obtained by test transformers and for high pulse-like processes such as artificial lightning discharges by Marx generators . In the field of physical experiments, maximum voltage is generated, for example, using high-voltage cascades or Van de Graaff generators .

Electrical voltages with peak values ​​above a few megavolts (MV) lead to partial discharges such as corona discharges in air and are technically no longer manageable above approx. 10 MV (= 10 million volts) due to the complex and spatially extensive insulation .

Web links

safety

As with all forms of high voltage are already in the contactless approaching participated bare conductors, ie without direct contact, voltage arcing possible. Therefore, the specified safety distances must also be observed here. Voltage breakdowns can occur with insufficiently insulated or damaged power cables .

Individual evidence

  1. ↑ Wolfgang Schuft: Taschenbuch der Energietechnik . Fachbuchverlag Leipzig by Carl Hanser Verlag, 2007
  2. ↑ TransmissionCode 2007. Network and system rules of the German transmission network operators ( Memento of the original from January 27, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. pdf, 916 kB @1@ 2Template: Webachiv / IABot / www.bdew.de
  3. ↑ Andreas Küchler: High voltage technology . 2nd Edition. Springer, 2005, ISBN 3-540-21411-9 (page 23).
  4. ↑ World's first 1100 kV UHVDC transformer. Retrieved February 24, 2019 .
  5. ↑ Hans Kemper: dangers d. Insert. - Electricity (fire brigade expertise) . ecomed-Storck GmbH, 2015, ISBN 978-3-609-69792-5 ( limited preview in Google Book Search [accessed December 9, 2016]).
  6. ↑ Kögler / Cimolino: Standard rules of use: Electric current in use . ecomed-Storck GmbH, 2014, ISBN 978-3-609-69719-2 ( limited preview in Google Book Search [accessed December 9, 2016]).
  7. ^ Heinrich Frohne, Karl-Heinz Locher, Hans Müller: Moeller Fundamentals of Electrical Engineering . Springer-Verlag, 2013, ISBN 978-3-322-93889-3 ( limited preview in Google Book Search [accessed December 9, 2016]).