What will I learn from this course?

Understand the role of HV Air-Insulated Substation, and gain insight on transformers, circuit breakers, disconnectors, surge arresters and instrument transformers.

Topics

• Role and function of a HV Substation
• Voltage levels associated with each network (LV, MV, HV, EHV, UHV)
• Network disturbances/distinguishing Internal & external insulation failures
• What factors determine the cost and architectural layout
• AIS vs. GIS
• Components found within an HV Substation
• SF₆ Gas (general overview)
• Innovative solutions for both AIS and GIS

• Definition and operating principle: transformation ratio
• Components (active part, winding layouts, insulation, bushings, conservator, cooling System, broad overview load vs. no load losses)
• Why and which tap changer is needed?
• Protection devices (lightning arrester, Buchholz relay, pressure relief device)
• History of power transformers
• Power transformer applications: generator transformer, auto-transformers, shunt reactor, HVDC converter transformer, smoothing reactor, furnace transformer, interconnection transformer, step-down transformer, rectifier transformer, trackside transformer
• Transformer definition and specification: insulation levels, impedance, temperature rise, loss capitalization, transportation
• Maintenance fundamentals

• Definition
• Components: interrupting chamber, support column, operating mechanism
• Circuit breaker types: Live Tank, Dead Tank, Hybrid Switchgear, Generator Circuit Breaker)
• Rated characteristics
• Design
• Interrupting chamber technology: quenching agents, open-close-open cycle
• Control & monitoring: closing resistors, grading capacitors, monitoring systems, RPH3)
• Circuit breaker in action during single phase or 3 phase fault
• Single-phase autoreclosure vs. 3-phase autoreclosure

• Definition
• Why do we need Instrument Transformers
• Roles: sensing, insulation, output
• Current Transformer (CT), Voltage Transformer (VT), Combined Metering Unit (CMU)
• Installation within the network
• Shunt and series connection
• Multiple secondaries, 1 common primary
• Single line diagram representations
• Current transformer designs: top core, hair-pin type, manufacturing, multiple ratios, reinforced security
• Voltage transformer designs: magnetic, single core or cascade construction, capacitor/coupling capacitor, metering, protection, multiple ratios
• Combined metering units advantages & limitations

• Definition and functions
• Open vs. closed position
• Installation within the network
• Selector switch disconnector vs. feeder disconnector
• Maintenance & safety
• Components: materials used, contacts, contact pressure, insulator, transmission, operating mechanism/drive, interlocks & arcing contacts
• Types: horizontal, vertical, including, center break, double side break, knee type, semi-pantograph, pantograph, vertical break