Explore six introductory questions about electricity generation and substation equipment. Open each answer to see an explanation and a related reading link.
1. How does a hydroelectric plant turn moving water into electricity?
Show answer to question 1
Water transfers energy to a turbine, which drives an alternator to produce electricity. The water source and plant arrangement vary. Read four examples of electricity generation. NIMI, PDF page 45.
2. Does a photovoltaic cell need a rotating generator to produce electricity?
Show answer to question 2
No. A photovoltaic cell converts energy from light into electricity using semiconductor materials. Other equipment, such as an inverter, may be used to condition the output. Read the generation overview. NIMI, PDF page 57.
3. What are two functions of insulating oil in an oil-filled transformer?
Show answer to question 3
It helps insulate internal electrical parts and carries heat away from them. The cooling arrangement depends on the transformer design. Read about transformer oil. NIMI, PDF pages 129–130.
4. What does a current transformer provide to a protective relay?
Show answer to question 4
It provides a secondary current related to the current in the primary circuit. A relay can use that signal as an input to a protection scheme. Read the current transformer FAQ. NIMI, PDF page 181.
5. What is the difference between a protective relay and a circuit breaker?
Show answer to question 5
A protective relay evaluates information for its protection function and can initiate a trip. The circuit breaker is the switching device that opens the circuit. Read the introduction to power-system protection. NIMI, PDF pages 67 and 326.
6. Do all gas-insulated switchgear installations have the same components?
Show answer to question 6
No. The arrangement depends on the equipment and station design. For example, Hitachi Energy lists some BLF/PASS components as available on request; that product list is not a universal GIS layout. Read the GIS introduction. Source: Hitachi Energy's BLF/PASS product description.
Sources
NIMI, Electrician (Power Distribution), 2nd Year Trade Theory; Hitachi Energy, GIS BLF/PASS.
Continue with the quiz on power-system faults and protection.