Advanced Protection Relay Testing

Introduction

This 5-Days “Instructor-Led” course has been designed to give plant and field engineers, and maintenance staff a better appreciation of the role played by power system protection systems.

An understanding of power systems along with correct management will increase your plant efficiency and performance as well as increasing safety for all concerned.

This course is designed to provide an excellent understanding of both theoretical and practical levels. The course starts at a basic level, to ensure that all participants have a solid grounding in the fundamental concepts and also to refresh the more experienced readers in the essentials. This course then moves onto more detailed applications. It is most definitely not an advanced treatment of the topic and it is hoped the expert will forgive the simplifications that have been made to the material in order to get the concepts across in a practical useful manner.

The course features an introduction covering the need for protection, fault types and their effects, simple calculations of short circuit currents and system earthing, and more. The course also refers to some practical work such as simple fault calculations, relay settings, and the checking of a current transformer magnetization curve which are performed in the associated training workshop.

Objectives

At the end of the course, the participants will get an excellent knowledge of the followings:-

• Power System.
• Electrical Equipment Damage and need for Protection.
• Fundamentals of electrical power protection.
• Functional Requirements of Protection Relays.
• Different fault types and their effects
• Performing simple fault and design calculations
• Power System Balanced Faults
• Introduction to Symmetrical Components
• Sequence Components and Fault Analysis
• Power System Unbalanced Fault
• Protection system components – CTs, VTs, CBs, fuses and relays.
• Relay settings; check, test and assess current transformers.
• Fundamental knowledge of different applications in protection.
• Motor faults and protections.
• Distribution Feeder Protective Devices.
• Important protections of Motor, Generator, Cables, and Transformers.
• Negative-Sequence Overcurrent Element Application and Coordination.
• Directional Element Application and Evaluation.
• Power System Protection coordination.

Training Methodology

This is an interactive course. There will be open question and answer sessions, regular group exercises and activities, videos, case studies, and presentations on best practice. Participants will have the opportunity to share with the facilitator and other participants on what works well and not so well for them, as well as work on issues from their own organizations. The online course is conducted online using MS-Teams/ClickMeeting.

Who Should Attend?

Any Person work in any of the following areas, you will benefit from this course…

• Design, installation, and maintenance engineers and technicians.
• Electrical engineers and technicians.
• Project engineers.
• Electrical maintenance, technicians, and supervisors.

Course Outline

Module (1): Review Power System Basics.

Module (2): Simple protection devices

• Direct-acting trip
• Thermal trip
• Time-limit fuses
• Thermal overload devices
• Oil dashpots
• Fuses
• Molded-case circuit-breakers

Module (3): Relays

• Induction relays
• Typical applications
• Attracted-armature relays
• Typical applications
• Moving-coil relays
• Thermal relays
• Timing relays
• Design
• Static relays

Module (4): Current and voltage transformers for protection

• Current transformers
• Construction
• Design
• Burden
• Operation
• Open-circuited current transformer
• Short-time factor
• Accuracy limit factor
• Specification of current transformers
• Rated secondary current
• Secondary winding impedance
• Primary windings
• Application
• Effect of CT magnetizing current on relay setting
• Residual connection
• Quadrature or air-gap current transformers
• Summation current transformer
• Voltage transformers
• Accuracy
• Protection
• Residual connection
• Capacitor voltage transformers.

Module (5): Fault calculations

• Impedance
• Fault level
• Generators
• Cables
• Source impedance
• Motors
• Practical example
• Current distribution
• Earth faults.

Module (6): Time-graded over current protection

• Settings
• Time-multiplier setting
• Application
• Discrimination with fuses
• Typical calculation
• Earth-fault protection
• Directional protection
• Directional relays
• Very inverse characteristic
• Extremely inverse characteristic
• High multiples of setting

Module (7): Unit protection

• Relays
• Application
• Protection of a motor
• CT knee-point voltage
• Overall setting
• The residual connection
• Busbar protection
• Phase and earth-fault schemes
• Settings
• Current setting
• Duplicate-busbar protection
• Mesh-connected substation
• Biased differential protection

Module (8): Transformer protection

• Types of fault
• Differential protection
• Magnetizing inrush
• Tap-changing
• Biased systems
• High-speed biased systems
• Earth-fault protection
• Protection of an earthed-star winding
• Protection of the delta winding
• Buchholz protection
• Overcurrent protection
• Instantaneous high-set overcurrent protection
• Overload protection
• Protection of a typical industrial installation
• Restricted earth-fault protection
• Balanced earth-fault protection
• Overcurrent protection
• Standby earth-fault protection

Module (9): Feeder protection

• Differential protection
• Factors affecting the design
• Practical systems
• Teed feeder differential protection
• Transformer-feeder protection
• Intertripping
• Auxiliary equipment
• Electronic relays
• Impedance protection

Module (10): Motor protection

• Abnormal conditions
• Overload protection
• Phase unbalance
• Stalling
• Insulation failure
• Settings
• Static relays
• Differential protection
• Loss of supply
• Synchronous motors

Module (11): Generator protection

• Insulation failure
• Earthling by resistor
• Earthling by transformer
• Stator protection
• Earth-fault protection
• Rotor earth-fault protection
• Unsatisfactory operating conditions
• Overcurrent protection
• Overload
• Failure of the prime mover
• Loss of field
• Overspeed
• Overvoltage
• Protection of generator/transformer units
• Unit transformers
• Parallel operation (public supply)

Module (12): Control circuits

• Batteries
• Power factor correction  

Module (13): Testing& Maintenance

• Works tests
• Tests on-site
• Commissioning tests
• CT magnetizing characteristic curves
• Relay characteristic check
• Static relays
• Insulation tests
• Tripping circuit check
• Routine maintenance tests
• Test equipment
• Care of protection relays

Module (14): Protection Coordination

• Introduction
• Time-graded Protection
• Time- and Current-graded Protection
• Time- and direction-graded protection
• Current- and Impedance-graded Protection
• Interlocking-based Protection
• Differential Protection
  • LOW-IMPEDANCE PRINCIPLE
  • HIGH-IMPEDANCE PRINCIPLE