Spänningsnivåomvandling
Spänningsnivåomvandling refers to the process of changing the electrical voltage level of a power system, typically by using transformers and switchgear. The technique is a fundamental part of electrical engineering, enabling the efficient transmission and distribution of electricity over long distances and to end users. By stepping voltage up, losses in transmission conductors can be reduced because higher voltage allows lower current for a given power level. Conversely, stepping voltage down makes the supply suitable and safer for homes, industry and equipment that operates at lower voltage levels.
The operation of a transformer is governed by the ratio of turns between its primary and secondary
In the Swedish power grid, voltage levels of 400 kV, 275 kV, 150 kV and 63 kV are common for transmission.
Spänningsnivåomvandling has technological, economic and regulatory implications. The Swedish Energy Agency imposes voltage standards and permits