The Primary and Secondary distribution in electrical systems

[Manon_Chaboud]

Understanding the fundamental distinction between Primary and Secondary distribution in electrical systems is pivotal for designing efficient and reliable electrical distribution systems tailored to specific needs across various domains.

Primary Distribution:

• Involves the transmission of high voltage electrical power from the source (e.g., power stations) to substations.
• Typically operates at voltages above 1 kV.
• Focuses on transmitting bulk power over long distances, often involving high-voltage equipment like transformers and circuit-breakers.

Secondary Distribution:

• Concerns the delivery of power from MV/LV transformers to end-users, such as residential, commercial, and industrial facilities.
• Operates at lower voltages, usually below 1 kV.
• Prioritizes power quality, reliability, and safety for end-users, utilizing distribution transformers, switchgear, and distribution lines.

[Manon_Chaboud]

Extended knowledge: Electrical Installation Guide (electrical-installation.org)

[Sylvain_C]

To complement the MV Primary and Secondary distribution, I would recommend downloading the MV Technical Guide which contains all the latest information on design, standards etc:
https://www.se.com/ww/en/work/products/product-launch/medium-voltage-technical-guide/

[RHH]

Thanks! Good to add here;
Within Low voltage there is also different levels and/or lines in distribution.
Starting with the Main supply Panel (called HVK or HKL around here mostly).
The main supply panel mostly and mainly located closest to or in the direct vicinity of the (MV/LV) Transformer.
If the building is big enough or the demand is there, there could be chosen for a main line distribution around the building with the help of busbar/busway or the common cable connections. Smaller panels are located throughout the building to ensure further and specific electrical distribution for certain parts/components within the building. To ensure protection and proper energy distribution throughout a building the electrical engineers must maintain good selectivity and protection with the help of components within the main panel and smaller panels throughout the building.

Find most SE products on the LV side here; https://www.se.com/ww/en/work/products/low-voltage-products-and-systems/

https://www.se.com/ie/en/download/document/SE12313/

Also very interesting and viable technical information about the ever changing buildings and distributions within self-sustainability (Microgrid);

https://www.se.com/nl/en/work/solutions/microgrids/