Premium Membership ♕

Limited Time Offer: Save 15% on Pro Plan with discount coupon: MX15. Study specialized LV/MV/HV technical articles and studies.

Home / Download Center / Electrical Engineering Books and Technical Guides / Power substation guides / Development of 22kV Distribution Systems and Switchgear

22kV Distribution System

The 22kV distribution is primarily directed at urban and other densely populated areas, and our efforts are focused on reducing overall costs (by making the equipment more compact and reducing equipment costs), by enhancing the distribution system to ensure improved reliability and better availability.

Development of 22kV Distribution Systems and Switchgear
Development of 22kV Distribution Systems and Switchgear (on photo: 20kV transformer substation; credit:

To optimize the distribution efficiency from substations, 22kV power may be distributed to the point of demand where it is stepped down to 6kV, or in other cases such as industrial zones and sparsely populated regions, power may be supplied by 6kV distribution systems.

Let us first consider the 22kV supply side equipment that is currently available.

22kV Low Voltage Direct Supply

1. Main and backup line system and loop systems

This is the most common system for receiving 22kV power. Since it has somewhat smaller transformer capacity than spot networks (SNWs), it is more economical both in terms of space and cost, and is therefore extensively deployed (see Figure 1).

Schematic Single-line Connection for Distribution Systems. Connections for main and backup line system (a) and SNW system (b).
Figure 1 – Schematic Single-line Connection for Distribution Systems. Connections for main and backup line system (a) and SNW system (b).

2. Spot network (SNW) systems

A spot network consists of the secondaries of three transformers connected together to maintain a constant source of supply even if one transformer fails.

SNWs are most commonly found in cities and other areas of high demand, and are seeing increasing deployment to exploit their advantages: Spot networks (SNWs) maintain a constant sources of supply, consist of secondaries of two or more transformers and therefore continue to supply power even when one line is down for inspection, and have a high degree of maintainability and operability.

SNWs are generally deployed as low voltage SNWs in which transformer secondaries supply low voltage power or as high voltage SNWs in which transformer secondaries supply 6kV to support efficient distribution within a single building (see Figure 1).

3. Regular network (RNW) systems

By interconnecting several RNWs on the low voltage side, load can continue to be supplied from another system in the event one system fails.

RNW systems maintain a constant source of supply and are generally applied in bustling shopping areas such as Ginza and Shinjuku in Tokyo.

However, this system is not being expanded because of the numerous requests from customers for 6kV power and because the system is insufficient in maintainability, operability and expandability.

Title:Development of 22kV Distribution Systems and Switchgear – Shuichi Kikukawa, Kenji Tsuchiya, Satoru Kajiwara and Akira Takahama
Size:1.4 MB
Download:Right here | Video Courses | Membership | Download Updates
Development of 22kV Distribution Systems and Switchgear
Development of 22kV Distribution Systems and Switchgear

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


    Feb 18, 2018


    We can analized distribution networks in many way ;
    -interconection in power station in fails way condition, for supply the customers without drop down energy;
    -pass energy from an line to other in different condtition;
    There are a lot relays protection for analize the function conditions in each electrical distribution station;
    – the relays protection for transformers cells(settings and communication protocols);
    – the relay protection for the lines(settings and communication protocols);
    -local controls of the cells(the interupters of cells);
    -the controls by remote of the cells (the interupters of cells );
    -the analize of events local( in relays) or to distances( control centers through SCADA);
    We can discuss a lot about an distribution system.
    For designs I consider that you can use the Electrical Solidworks software which it is very good for such projects.

    Thank you

  2. Yousef
    May 14, 2017


    Thank you for uploading this file. The number of pages does not match what is posted (7 vs 84), is this a typo or there might be more than one document?
    Thank you,

    • Edvard
      May 14, 2017

      It’s a typo. Sorry for the confusion, this is the document and number of pages is 7.

  3. Alfred Gjylameti
    Nov 02, 2016

    I need a design program for 20kV overhead transmission lines.

    Thank you

Leave a Comment

Tell us what you're thinking. We care about your opinion! Please keep in mind that comments are moderated and rel="nofollow" is in use. So, please do not use a spammy keyword or a domain as your name, or it will be deleted. Let's have a professional and meaningful conversation instead. Thanks for dropping by!

seventy three  −  sixty three  =  

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