Substation Engineering

Substation Engineering – up to 400kV

Executed Orders in Substation Engineering:

Wo.No Order description Project Status
1. Preparation of power and control cable schedule - 400kV Alamathy& Thervaikandigai. Completed
2. 400/230/110kV SS Kanarpatti - Electrical and civil- drawing and design calculation. Completed
3. Testing of 11kV VCB at ARPSL factory. Ongoing
4. 400kV SWYD Lighting design- thervaikandigai Completed
5. 110kv Bay extention at ammayanaikanur SS. Completed
6. 132kV SS civil and Structural Engineering. Completed
7. 132/33kV SS detailed engineering electrical,civil & structural. Hold
8. 230/132kV Jammbunathapuram SS detailed engineering-electrical,civil & structural. Completed
9. 400/230/110kV SS Kamudhi - detailed engineering-electrical and civil. Ongoing
10. 69kV Switchyard Tower Design and Drawing Completed
11. 400/230/110kV SS_Thennampatti_detailed engineering-electrical and civil. Ongoing
12. Supply and installation of 250kVA DG set, power cable, Earthing materials etc., Ongoing
13. 220kV Switching station detailed engineering at Ayyanahalli - Karnataka. Completed


Substations are important components of the electrical infrastructure required to keep reliable electricity available for Customers.Substation consists of high voltage electrical equipment like transformers, switch gear, Circuit Breakers and Associated Devices.

The Purpose of a Substation is to Step down High Voltage Electricity from the Transmission system to lower Voltage Electricity. So it can be easily supplied to homes and businesses through distribution lines.

  • Change Voltage from one level to another.
  • Regulate Voltage to Compensate for system Voltage changes.
  • Switch transmission and Distribution circuits into and out of the Grid System.
  • Measure Electric Power Qualities flowing in the circuits.
  • Eliminate lightning and other electrical surges from the system.
  • Connect Electrical Generation Plants to the System.
  • Make interconnections between the Electric Systems of more than one utility.
  • Control reactive Kilovolt-amperes supplied to and the flow of reactive Kilovolt – Amperes in the Circuits.

Substation – Electrical:

Primary Engineering:

  • Single Line Diagram, PSLD
  • Switchyard Layout Plan and Section
  • Earthing Calculation and Layout
  • Cable Trench Layout
  • Erection Key Diagram
  • Lighting, Lightning design calculation and Layouts
  • SCF and Sag Tension Calculation

Secondary Engineering:

  • CT, VT, Cable and Battery Sizing Calculation and Selection
  • Control and Protection (CRP) Scheme Design
  • Control and Power cable termination schedule
  • Relay Setting Calculation
  • Protection Audit

Substation – Civil & Structural:


  • Drawings and Design calculation for Support Structure, CT, PT, CB, LA, Isolator, Tower and Girder
  • LM tower drawing and design calculation
  • Drawings and Design Calculation for station transformer support structure


  • Control Room drawings, design and Calculation
  • Overall equipment foundation Layout
  • Power Transformer Foundation details and design Foundation Details and design for Substation
  • Equipments CT, PT, CB, Isolator, Earth Switch Etc., Tower Foundation details
  • Details of Road, Culvert, Fencing and Gate