SUBSTATION DESIGN, CONSTRUCTION AND MAINTENANCE

SYNOPSIS

The scarce skills combined with the ageing and retiring of experienced substation design engineers have called for getting young and new substation engineers familiar with the fundamental aspects of substation design and construction. In this course, delegates will be guided through a step-by-step technique of substation design, construction and maintenance processes. All phases for substation design, from initial site review, selection, and grounding design, all the way to substation start-up and commissioning, will be covered. Exercises, group discussions, pictures and videos will be used to further demonstration of concepts.

Module 1: Introduction

• Classification of sub-stations and purposes
• Comparison between indoor and outdoor substations
• Transformer substations, pole mounted substations, underground substations
• Bus-bar arrangement in substations
• Key diagram of 66/11 substation, 11kV/400 V substation

Module 2 : Substation design considerations

• Site selection
• Environmental considerations
• Safety considerations
• Maintenance considerations

Module 3 : Substation Physical layout

• Layout considerations
• Distribution substations
• Transmission substations
• Switching stations
• Typical bus configurations
• Protection of substation insulation
• Electrical clearances
• Bare conductors
• Rigid bus design
• Application of mobile transformers and substations

Module 4 : Selection and application of Substation equipment  

• Major substation equipment: Power transformer, power circuit breakers, Metal Clad switchgear, substation voltage regulators, shunt capacitor equipment, air switches, surge arresters, automatic circuit reclosers, instrument transformers, coupling capacitors and coupling capacitor voltage transformers, mobile units
• indoor cellular substations, gas-insulated substations (GIS) and 22kV-132kV mobile substation skids for open-cast mining

• Secondary Substation Equipment
• Auxiliary Equipment and Systems
• Protective Relaying and Control
• Bill of materials (BOM) and Bill of quantities (BOQ)
• Substation control and automation

Module 5: Design of Substation grounding system

• Differences in earthing design for various voltage levels (HV, MV & LV)
• Earthing design flowchart
• Grid Design Procedures and data requirements
• Substation earthing system components
• Common Substation earthing conductors
• Preliminary Design
• Main earth grid installation layout
• Computation of Mesh Voltage, Step potential, Touch potential and Ground potential rise (GPR)
• Equipment earthing
• Yard surfacing
• Fences
• Use of Computer Analysis in Grid Design
• 132/11 kV substation earthing practical design example
• 132/33 kV substation earthing practical design example

Module 6 Substation Maintenance Program

• Circuit Breaker Maintenance
• Dissolved Gas Analysis
• Oil Quality: Dielectric Strength, Acid, Interfacial Tension, Power Factor, Water
• Relay maintenance – Electro-mechanical relays only
• Relay functional testing – All relays
• Battery Maintenance – Capacity discharge testing, Intercell resistance, Specific gravity, Temperature, Electrolyte level
• Series Capacitor Bank, Maintenance
• Thermographic (infrared) Inspection
• Equipment Inspections
• Public Safety Inspections: Warning signs, Fence and gate integrity, Ground erosion, Vandalism, Vegetation, outside grading or other providing, potential access
• Doble Testing: Overall tests, Bushing tests, Hi-collar tests, Oil tests, Surge arrester tests, SFRA and LR testing
• Assessment