The Power System Protection course includes the following individual learning activities (ILA). CEH awarded are 30 Standards, 34 Operating Topics and 34 EOP.
ILA #1 (4 CEH)
Learning Objectives:
1. State the fundamental purpose of protective relaying ~ list and define important relaying terms
2. Describe the types of relays
3. Describe the quantities & events monitored by protective relays
4. Describe the types of protective relays
5. List and describe the IEEE device numbers
6. State the goals of protective relaying
7. Explain the concept of zones of protection
Learning Activity Content:
1. State the fundamental purpose of protective relaying and state and explain the definition of a relay and of a protective relay
2. Describe the function of various types of relays including protective, regulating, monitoring, auxiliary, and synchronizing
3. List the quantities monitored by relays and list the abnormal events relays protect against
4. Describe and illustrate the types of protective relays including electro-mechanical, solid-state and microprocessor
5. List and explain the IEEE device numbering system
6. List and describe the goals of protective relaying and include a description of reliability, selectivity, speed, simplicity and economics as these terms apply to protective relaying
7. Illustrate and explain the concept of a zone of protection
ILA #2 (4 CEH)
Learning Objectives:
1. Explain the purpose and demonstrate the usage of the per-unit system
2. Explain the purpose and illustrate the usage of vectors and phasors
3. Explain the purpose and illustrate the usage of transformer polarity
4. Explain the purpose and illustrate the usage of symmetrical components
5. Explain the purpose and illustrate the usage of a polarizing quantity
Learning Activity Content:
1. a) Explain the purpose of the per-unit system b) Demonstrate the usage of per-unit quantities and formulas c) Convert between per-unit and ohmic values
2. a) Explain the purpose of vectors and phasors b) Illustrate phasors using 3-phase transformer connections
3. a) Explain the concept of transformer additive and subtractive polarity b) Demonstrate the usage of polarity markings
4. a) Explain the concept of symmetrical components b) Describe the positive, negative, and zero sequence components c) Explain sequence component mathematical relationships d) Create sequence component diagrams and calculate fault currents using sequence component concepts
5. Illustrate how transformer neutrals can be zero sequence current sources and describe the importance of the polarizing quantity for determining direction
ILA #3 (4 CEH)
Learning Objectives:
1. Explain the purpose and illustrate the concept of instrument transformers
2. Explain the purpose and illustrate the concept of differential relays
3. Explain the purpose and introduce the concept of over-current and distance relays
4. Explain the purpose and illustrate the concept of backup protection
5. Explain the purpose and illustrate the operation of electro-mechanical relay designs
6. List and describe the advantages and disadvantages of microprocessor relays
7. Explain the purpose and illustrate the concept of power system grounding
Learning Activity Content:
1. a) Describe the purpose and operation of instrument transformers b) Create and explain the usage of an instrument transformers circuit diagram c) Explain the concept of saturation with respect to current transformers
2. a) Describe and illustrate the differential relay concept b) Describe the operation of the % differential restraint function
3. a) Describe and illustrate the basic application of over-current and distance relays for equipment protection b) Describe how coordination can be achieved via either a time solution or a communication solution
4. a) Describe and illustrate the protective relay backup concept b) Explain the difference between primary backup, local backup and remote backup
5. a) Explain and illustrate how electro-mechanical devices are used to perform protective relay functions b) Illustrate and describe induction disk, clapper, plunger, balanced beam, and directional sensing electro-mechanical designs
6. a) List and describe the advantages of microprocessor relays b) List and describe the disadvantages of microprocessor relays
7. a) Explain the purpose of power system grounding b) Describe the differences between un-grounded, high impedance grounded, low impedance grounding, and solid grounding c) Describe the voltage shift when a ground fault occurs in an un-grounded system d) State the purpose of safety grounding
ILA #4 (4 CEH)
Learning Objectives:
1. Describe the different types of generators including the different methods of connecting the generators to the system
2. Illustrate and describe the protection typically applied to direct-connected generators
3. Illustrate and describe the protection typically applied to unit-connected generators
Learning Activity Content:
1. a) State the definition of a DG and of a BPG b) Describe how generators are either direct connected or unit connected c) State the hazards that DGs and BPS are typically protected against
2. Describe how direct connected generators are protected from the occurrence of the following hazards
− Phase / ground faults in the stator
− Ground faults in the rotor
− Loss of field excitation
− Motoring
− Over-excitation
− Synchronizing issues
− Unbalanced currents
− Abnormal frequency operation
− Delayed clearing of system faults
− Over-voltage
− Intertie faults
3. Describe how unit connected generators are protected from the occurrence of the following hazards
− Phase / ground faults in the stator
− Ground faults in the rotor
− Loss of field excitation
− Motoring
− Over-excitation
− Synchronizing issues
− Unbalanced currents
− Abnormal frequency operation
− Delayed clearing of system faults
− Over-voltage
− Loss of VT signal
ILA #5 (4 CEH)
Learning Objectives:
1. Explain the issues associated with power transformer protection
2. Describe how protective relays are used to provide protection for power transformers and shunt reactors
3. Describe how protective relays are used to provide protection for phase shifting transformers (PSTs)
4. Describe how protective relays are used to provide protection for shunt capacitors
Learning Activity Content:
1. Describe and illustrate how the following issues impact power transformer protection
− In-rush current
− Excitation current
− CT saturation
− Absence of high side interrupting device
2. Describe how transformers are protected from the occurrence of the following hazards
− Over-excitation
− Internal ground and phase faults
− Gas build up
− Thermal damage
− Primary protection failure
3. a) Describe the construction and operation of a PST b) Describe and illustrate the protection of a PST
4. Describe the protection used for a high voltage shunt capacitor bank include a description of voltage imbalance protection
ILA #6 (6 CEH)
Learning Objectives:
1. Describe the differences in protecting radial versus looped transmission lines
2. Describe and illustrate how distance relays are applied for transmission line protection
3. Describe and illustrate transmission line backup protection
4. Describe and illustrate the operation of the most common types of pilot protection schemes
Learning Activity Content:
1. a) Differentiate radial line protection from looped line protection b) Explain the coordination issues involved in looped line protection
2. a) Describe and illustrate a multi-zone distance protection system b) Explain the in-feed effect c) State the advantages of a reverse zone 3
3. a) State the difference between the backup function provided by redundant relays and remote backup b) Create and describe the usage of a backup protection DC schematic
4. Describe and illustrate the operation of the following pilot protection schemes
− Permissive Over-Reaching Transfer Trip (POTT)
− Permissive Under-Reaching Transfer Trip (PUTT)
− Directional Comparison Blocking (DCB)
− Directional Comparison Un-Blocking (DCU)
− Line Current Differential (LCD)
− Directional Wave Comparison
ILA #7 (4 CEH)
Learning Objectives:
1. Explain and illustrate out-of-step protection
2. Describe the advantages and disadvantages of automatic reclosing
3. Describe how under-voltage load shedding systems are used to avoid voltage collapse
4. Describe how under-frequency load shedding systems are used to avoid frequency collapse
5. Explain the purpose and application of special protection systems
Learning Activity Content:
1. a) Utilize power angle curves to explain the concept of angle stability b) Illustrate an out-of-step swing on an R-X diagram c) Describe how impedance relays can be used to detect out-of-step swings
2. a) Explain the purpose and describe the issues associated with automatic reclosing in the high voltage transmission system b) Use power angle curves to demonstrate advantages and disadvantages of automatic reclosing
3. Explain the purpose and describe the issues associated with the use of under-voltage load shedding relays to avoid a voltage collapse
4. Explain the purpose and describe the issues associated with underfrequency load shedding relays to avoid a frequency collapse
5. a) Explain the purpose of a special protection system or SPS b) Illustrate the concept of an SPS using the WECC-1 SPS as an example
ILA #8 (4 CEH)
Learning Objectives:
1. Describe the purpose and illustrate the design of the substation bus configurations commonly applied in the Bulk Electric System
2. Describe and illustration how current and voltage differential protection is applied to various substation configurations
3. Describe the content of the NERC PRC series of Reliability Standards
Learning Activity Content:
1. Describe and illustrate the following bus configurations
- Single Bus / Single CB
- Main & Transfer
- Ring
- Breaker-&-a-Half
- Double Bus / Double CB
2. Describe and illustrate the application of differential relays for the following substation configurations:
− Single Bus / Single CB
− Main & Transfer
− Ring
− Breaker-&-a-Half
− Double Bus / Double CB
3. a) Describe the content of the NERC PRC series of Reliability Standards b) Include a brief description of the content of each of the 22 standards in the PRC classification
