Project Overview

EDC Firm was engaged by CCC Engineering Ltd. (CCCE) to provide electrical protection engineering consultancy services for 8 nos. substations under DESCO as part of a turnkey EPC project. Under this separate work order, EDC Firm is responsible for Relay Setting Calculation and Relay Coordination Study to support the safe, reliable, and selective operation of the substation protection system.

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Project Details

• Project Title: Dhaka Power System Expansion & Strengthening Project, DESCO Area. Lot1: Design, Manufacture, Supply, Installation, Testing and Commissioning of 08 nos. (04 nos. 132/33/11kV GRID and 04 nos. 33/11kV) Substation on Turnkey basis
• Client(EPC): CCC Engineering Ltd. (CCCE)
• End Client(Owner): Dhaka Electric Supply Company Limited (DESCO)
• Project Type: Protection Engineering & Relay Coordination Study
• Service: Relay Setting Calculation & Protection Coordination
• Project Value:
• Status: 15% Completed

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Substations Covered

• 4 × 132/33/11 kV Grid Substations (Airport, Tongi, Kalshi & Bashundhara)
• 4 × 33/11 kV Distribution Substations (Uttara, Mirpur Ceramics, Purbachal & Kalachadpur)

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Scope of Work

Relay Setting Calculation

• Collection and review of relevant system and equipment data
• Review of protection schemes, short circuit current calculation report and single-line diagrams
• Relay setting calculation for applicable protection functions
• Overcurrent/Earth Fault, Distance, Differential, Fault Locator protection setting
• Protection parameter development for applicable relay types
• Preparation of relay setting schedules

Relay Coordination Study

• Protection coordination analysis between upstream and downstream protection devices
• Time-Current Characteristic (TCC) analysis
• Assessment of protection selectivity and discrimination
• Coordination of feeder, transformer and incoming protection
• Review of relay operating times and coordination margins
• Identification of potential coordination issues
• Recommendation of optimized protection settings

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Engineering Deliverables

• Relay Setting Calculation Reports
• Protection Coordination Study Reports
• Relay Setting Schedules
• Protection Coordination Curves
• Protection Setting Summary
• Engineering Calculation Sheets
• Technical Documentation

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Standards Followed

• Applicable IEC Standards
• Applicable IEEE Standards
• Relevant relay manufacturer technical data
• DESCO & PGCB applicable engineering requirements and protection philosophy
• Approved project design documents and system data

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Engineering Approach

• EDC Firm's protection engineering approach focuses on achieving reliable fault detection, selective protection operation, appropriate coordination margins, and minimum unnecessary interruption of the electrical network.
• The relay settings and coordination study are developed based on the available system configuration, equipment ratings, protection characteristics, and applicable project requirements.

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Conclusion

This project demonstrates EDC Firm's capability in providing specialized electrical protection engineering services for grid and distribution substations. Through relay setting calculation and protection coordination studies, EDC Firm supports the development of a reliable, selective, and technically coordinated substation protection system for DESCO's power distribution network.