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Consultancy services for electrical substations
consultancy in the field of electrical substations is one of the most specialized and vital engineering services, covering all stages of a substation's life cycle, from the initial idea to decommissioning. The ultimate goal of these services is to ensure the safety, reliability, cost-effectiveness, and sustainability of the project.
In the following section, I will explain the different types of these services, categorized by project phase and substation type.
Categorization of consulting services based on project phases

1. Preliminary Studies and Feasibility Studies

Objective: to answer the question, "Is the construction of this substation technically and economically justified?"
Key activities:
Load and Load Flow Study: forecasting the load of the covered area and determining the required substation capacity.
Network configuration study: determining the optimal location for substation construction (Site Selection) in terms of network losses and stability.
Techno-Economic review: comparing different options (Overhead Substation vs. GIS, different voltage levels) and presenting the most economical choice.
Environmental Impact Assessment (EIA): for large-scale projects.

2. Engineering Design

This is the most comprehensive part of consulting services and involves various engineering disciplines:

A) Basic Design:
Preparation of a Single Line Diagram (SLD): determining the arrangement of circuit breakers, disconnectors, and equipment.
Technical studies and calculations:
Load flow study: using software such as ETAP or DigSILENT.
Short-Circuit study: to determine the withstand capacity of equipment.
Protection coordination study: for setting relays and designing the protection system.
Arc Flash study: for personnel safety.
Transient Stability study: for very large substations.
Equipment selection: preparing Technical Specifications and Data Sheets for the procurement of all equipment (transformers, circuit breakers, CTs/VTs, etc.).

B) Detail Design:
Design of execution drawings: layout drawings, wiring and interconnection diagrams, grounding and foundation drawings.
Earthing System Design: using specialized software like CDEGS or SES Shield.
Design of the Lighting System and Auxiliary Power System.
Design of the Control and SCADA System: designing the control system architecture, selecting PLCs, and designing HMI screens.

3. Tendering and Procurement

Preparation of tender documents: including all technical specifications, contract terms, and financial documents.
Technical  evaluation: comparing offers from different vendors and ensuring their compliance with technical specifications.
Contract finalization and expediting: monitoring the manufacturing process of equipment at the factory and attending Factory Acceptance Tests (FAT).

4. Construction Supervision

Supervision of civil works: quality control of foundation construction, control room building, and grounding grid.
Supervision of equipment installation: ensuring correct installation according to execution drawings.
Inspection and Quality Control (QC): inspection of connections, welds, painting, etc.

5. Commissioning Supervision

Planning and supervision of Site Acceptance Tests (SAT): ensuring the correct functionality of all installed equipment.
Substation energization: supervising the process of energizing the substation step-by-step.
Temporary and Final Takeover (TOC & FOC): taking over the substation from the contractor and providing training to the operation personnel.

6. Operation and Maintenance Consultancy

Developing operating procedures.
Developing Preventive Maintenance (PM) Programs.
Analyzing Dissolved Gas Analysis (DGA) data and providing reports on transformer health status.
Holding specialized training courses for operators and maintenance technicians.
Troubleshooting and problem resolution during failures.

7. Optimization and Upgrading

Condition assessment: evaluating the health of existing equipment in old substations.
Proposing retrofitting and modernization plans: replacing old breakers with modern ones or digitalizing the protection and control system.

Consulting services based on substation type

High Voltage/High Voltage (EHV/HV) Substations:
Emphasis on comprehensive power system studies (stability, short-circuit).
Highly complex and critical grounding system design.
Choosing between AIS (Air-Insulated) and GIS (Gas-Insulated Switchgear) technologies.
Managing high project risks.

Medium Voltage (MV) Substations:
Emphasis on optimal load distribution in the network.
Designing protection systems for ring main networks.
Choosing between overhead, ground-mounted, or prefabricated substations.

Low Voltage (LV) Substations:
Emphasis on designing distribution panels and protection coordination between various breakers.
Calculating the short-circuit level and selecting equipment with appropriate withstand capacity.
Energy consumption optimization and designing capacitor banks for power factor correction.

Specialized software used by consultants:

Power system analysis: ETAP, DigSILENT PowerFactory, PSS®E
Grounding system design: CDEGS (SES), AutoGround
Design and modeling: AutoCAD, MicroStation, Revit (BIM)
Electromagnetic simulations: ANSYS EM, COMSOL
Project management: MS Project, Primavera P6

Final Summary
A good consulting company is like an architect who draws the master plan and supervises its correct implementation. Using technical expertise, experience, and advanced software, they protect the client's major investment and ensure that the designed substation continues to operate safely and reliably for decades. These services are especially essential for utility companies (like Tavanir, regional power distribution companies) that may not have the specialized human resources for all these phases in-house.