System Protection Training

350-01 Elements of System Protection

When you complete this lesson you will understand the basic principles of system protection. Additionally, you will understand the basic equipment and methods deployed to realize protection principles.

  • Identify the philosophy and objectives of system protection
  • Recal zones of protection
  • Identify the importance of protection coordination
  • Identify the three different levels of backup protection
  • Describe different types of breaker construction
  • Describe the function of a basic relay protection schematic
  • Identify the basic functions of commonly used relays

350-02 Types of Protective Relays

When you complete this lesson you will understand the basic operating principles of common protective relays and how they are employed in protection systems.

  • Recall the purpose of relay protection schemes
  • Identify the eight types of transmission circuits subject to relay loadability
  • Identify the five types of generation facilities subject to relay loadability
  • Recall the evolution of relay design
  • List the three major types of relay construction and explain how they differ
  • Identify the conditions causing the basic operation of instantaneous relays
  • Identify the strengths and limitations of instantaneous relays
  • Identify the strengths and limitations of time delay relays
  • Identify the strengths and limitations of differential relays
  • Recall how directionality can be obtained in an AC power system
  • Recall how impedance is used to detect faults on the electric system
  • Identify why overlapping zone protection is needed when using impedance relays

350-03 Monitoring System Conditions

When you complete this lesson you will understand the purpose of PRC-002-2, and how system conditions are monitored through the application of per-unit measurements, AC polarity, and basic potential transformer and current transformer construction and operation.

  • Identify settings established in R1 through R4 of PRC-002-2
  • Recall how the per-unit scale differs from percentage comparisons
  • Recall how phasors and vectors are related
  • Identify phasor application in a three phase power system
  • Recall the phase relationship between phase to neutral and phase to ground voltage measurements
  • List the basic components of a transformer
  • Calculate the secondary output of a transformer given input values and turns ratio
  • Recall the difference between VTs, PTs, and CCVTs
  • Recall the relationship between primary and secondary current as magnetic flux reaches saturation
  • Recall how relays are connected to PTs and CTs and how this relates to burden

350-04 Disturbance Monitoring Equipment

When you complete this lesson, you will be able to explain why DME is required, identify and apply guidelines of applicable NERC standards, recognize types and applications of common DME, and conduct accurate DME data reporting.

  • Identify the purpose of Disturbance Monitoring Equipment (DME)
  • Recall the two universal requirements of DME installation
  • Identify the common types of DME
  •  Recall NERC requirements for Disturbance Monitoring and Reporting
  •  Recall NERC requirements for DME installation and Data Reporting
  • Recall the four types of data required for a three year archive
  • Recognize DME application with the four DME application measurements
  • Recall the considerations of disturbance recording and analysis

350-05 Line Protection

When you complete this lesson you will understand basic power system line relay loadability and how various protection methods are applied to isolate faults on these systems.

  • Recall the purpose of Transmission Relay Loadability
  • Identify the applicability of PRC-023-4 to functional entities
  • Recall the process of coordinating protection between fuses and overcurrent protection relays
  • Recall the difference between fuse saving and fuse blowing protection schemes
  • Identify the strengths and weaknesses of using overcurrent protection relays
  • Identify the strengths and weaknesses of using distance relays
  • Recall how ground fault relay settings are different between distribution and transmission systems
  • Recall the process by which mutual induction can cause false trips in adjacent lines
  • Define overlapping zones of protection
  • Identify methods of protection against voltage instability
  • Recall the difference between manual and automatic load shedding

350-06 Transformer Protection

When you complete this lesson you will understand the basic construction and protection methods commonly used in transformer protection.

  • Describe the basic construction of a common power transformer
  • Identify the different types of transformer faults
  • Identify the different types of pressure protection
  • Describe the advantages and disadvantages of using fuses, circuit switchers, and circuit breakers for overcurrent protection
  • Describe how ground fault protection is able to distinguish between an internal and external fault
  • Describe the basic operation of differential protection
  • Identify the different methods used to manage inrush current
  • Identify the conditions required in order for reactor banks to perform similar to transformers
  • Describe how capacitor banks detect and protect against severe imbalance
  • Identify the limitations of differential protection with phase shifting transformers

350-07 Pilot Protection

When you complete this lesson you will understand the major forms of communications channels used by pilot protection, as well as the basic functions of the more common pilot protection schemes deployed in power system protection.

  • Recall why pilot protection systems are needed
  • Identify the strengths and weaknesses of the major communications channels
  • Identify which communications mediums are capable of high bandwidth data transmission
  • Identify the differences between permissive, blocking, and direct transfer trip schemes
  • Recall how pilot protection both manipulates and makes use of time delays
  • Define the difference between overreaching and underreaching schemes

350-09 Bus Protection

When you complete this lesson you will understand the six basic substation bus configurations, as well as the various relaying systems used to protect them.

  • Define the basic construction types for substations
  • Identify the strengths and weaknesses of the six prominent bus configurations
  • Define how a fault on a bus would impact each of the six different bus configurations
  • Define how backup protection can be made to respond quicker to bus faults
  • Define how fault bus protection can present a hazard to personnel
  • Define how CT saturation causes issues with basic differential protection
  • Define how high impedance relaying mitigates CT saturation effects
  • Define how linear couplers completely eliminate saturation issues

350-10 Generator Protection

When you complete this lesson you should understand generator protection schemes and NERC standards as they apply to generator protection methods and requirements.

  • Identify common internal faults of generation units
  • Identify reportable systems conditions of PRC-019-2
  • Recall external system conditions on generation units
  • Define the term Composite Protection System
  • Recall applications of Composite Protection Systems
  • Recall the purpose of UFLS programs
  • Recall generator relay settings and loadability
  • Identify common protective relay loadability schemes

350-11 Protection System Misoperation

When you complete this lesson, you will be able to define the term Misoperation, and identify conditions registering as such.

  • Describe the two aspects of protection system design
  • Describe the process of analyzing Protection System Misoperation
  • Describe the process of developing and implementing a Corrective Action Plan (CAP)
  • Identify evidence required to prove compliance with CAP procedures
  • Explain Responsible Entity compliance with PRC-004-5(i)
  • Describe the timelines for identifying the cause of a Misoperation for compliance with PRC-004-5(i)
  • Identify the facilities subject to regulation of PRC-005-6
  • Explain Functional Entity compliance with PRC-005-6

350-12 Protection Systems Maintenance Programs

When you complete this lesson, you will be able to identify protection system terminology and assets and comply with applicable NERC standards.

  • Discuss basic terminology associated with protection system maintenance programs
  • Discuss critical considerations of Protections Systems Maintenance
  • Discuss the fundamentals of Protection Systems Maintenance Programs
  • Identify and discuss the three types of Protection System Maintenance Programs
  • Identify and discuss common Protection System Maintenance practices