Premium Membership ♕

CYBER WEEK OFFER 💥 Save 20% on PRO Membership Plan and Video Courses with the coupon CYM23 (Expires in 2 days).

Home / Premium Content / Advanced Electrical Engineering Guides / Design, implementation and commissioning of substation automation systems (SASs)

Substation Components and SAS

Large substations usually have four standard physical environments: The main control house, one or more local control rooms, the switchyard and the voltage transformation area. The switchyard may have different appearances, mainly depending on the substation insulation media (air‐insulated or gas‐insulated) and its design for environmental exposition (outdoor or indoor).

Design and Implementation Of Substation Automation Systems (SASs)
Design and Implementation Of Substation Automation Systems (SASs) – photo credit: SEL

In case of air‐insulated substations, the primary equipment are svelte structures made of porcelain or polymeric material that provide electrical insulation between the energized upper part and the substation earth plane. Some of this apparatus is filled with gas, such as puffer type circuit breakers, which contain sulfur hexafluoride (SF6).

Others are filled with dielectric oil, such as instrument transformers and power transformers.

In the substation yard, switchgear, instrument transformers and other primary apparatus are mounted on metallic structures to achieve the minimum standardized safety distances for internal circulation and movement of people and vehicles, such as that shown in Figure 1.

This chapter covers SAS related details of substation components installed in the switchyard.

Primary Equipment

In the lexicon of power systems, operating voltages applicable to equipment and devices have been classified as follows:

  • Low voltage: When the 3-phase system voltage is less than 1kV.
  • Medium voltage: When the 3-phase system voltage is above 1kV and less than 52kV.
  • High voltage: When the 3-phase system voltage is from 52kV to less than 300kV.
  • Extra high voltage: When the 3-phase system voltage is from 300kV to 765kV.
  • Ultra high voltage: When the 3-phase system voltage is above 765kV.

The primary equipment of a transmission substation operates at standardized rated voltages, such as 72.5, 123, 145, 245, 420, 525 and 765 kV, whilst in most distribution substations, primary equipment works at lower standardized voltages, such as 7.2, 12, 24 or 36 kV.

Premium Membership Required

This technical article/guide requires a Premium Membership. You can choose an annually based Plus, Pro, or Enterprise membership plan. Subscribe and enjoy studying specialized technical articles, online video courses, electrical engineering guides, and papers. With EEP’s premium membership, you get additional essence that enhances your knowledge and experience in low- medium- and high-voltage engineering fields.

Check out each plan’s benefits and choose the membership plan that works best for you or your organization.

CYBER WEEK DEAL 💥 – Save 20% on PRO plan with the coupon CYM23.

Log In »Purchase »

Premium Membership

Get access to premium HV/MV/LV technical articles, advanced electrical engineering guides, papers, and much more! It will help you to shape up your technical skills in your everyday life as an electrical engineer.
50% Discount 💥 - Save 50% on all 90+ video courses with Enterprise Membership plan.

More Information

Learn How to Design Power Systems

Learn to design LV/MV/HV power systems through professional video courses. Lifetime access. Enjoy learning!

Subscribe to Weekly Newsletter

Subscribe to our Weekly Digest newsletter and receive free updates on new technical articles, video courses and guides (PDF).
EEP Academy Courses - A hand crafted cutting-edge electrical engineering knowledge