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SUBSTATIONS
CHAPTER OBJECTIVES
_✓ Identify all major equipment used in substations
_✓ Describe the purpose and operation of each major equipment type
_✓ Discuss the different types of transformers
_✓ Explain the operation of voltage regulators and tap changers
_✓ Understand the advantages and disadvantages of oil and gas
equipment
_✓ Discuss the different types of circuit breakers and how they are used
_✓ Explain the purpose of capacitors, reactors, and static VAR
compensators used in electric power systems
_✓ Discuss the equipment found in control buildings
_✓ Discuss the effective preventative maintenance programs used for
substation equipment
SUBSTATION EQUIPMENT
The major types of equipment found in most transmission and distribution
substations are discussed in this chapter. The purpose, function, design
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characteristics, and key properties are all explained. After the equipment is
discussed, planned and essential predictive maintenance techniques are discussed.
The reader should get a good fundamental understanding of all the
important aspects of the major equipment found in substations and how they
are used and operated.
The substation equipment discussed in this chapter includes:
_ Transformers
_ Regulators
_ Circuit breakers and reclosers
_ Air disconnect switches
_ Lightning arresters
_ Electrical buses
_ Capacitor banks
_ Reactors
_ Static VAR compensators
_ Control building
_ Preventative maintenance
TRANSFORMERS
Transformers are essential components in electric power systems. They
come in all shapes and sizes. Power transformers are used to convert highvoltage