Electrical equipment maintenance and testing is one of the most important aspects of the substation system. Without protection, any system could fail. So it is imperative that safety and protection be given utmost importance to avoid catastrophes. For fault locating to be efficient and accurate technical staff must have expert knowledge to keep employees safe while working on or around high voltage power generation, transmission and distribution systems and equipment.
This course is designed to help students to understand the substation design and safety procedures to provide a safe environment for substation personnel.
WHO SHOULD COMPLETE THIS COURSE
- Electrical Technicians
- Substation design engineers
- Distribution planning engineers
- Substation network management engineers
- Substation maintenance and construction engineers & technologists
- Engineering Managers
- Risk Assessors
- Design Engineers
- Manufacturers of PPE & Safety Equipment
- Safety Facilitators
- Instrumentation & Control Technicians and Engineers
- Process Safety and Loss Prevention Managers
- OHS/Training Managers
COURSE OUTLINE
INTRODUCTION TO SUBSTATION
- Definition
- Role of substations in a power network
- Types of substations
DESIGN CONSIDERATIONS OF A SUBSTATION
- Overview
- Other classifications of substation
- Need for a new substation
- Considerations for locating substations
- Design factors
SUBSTATION CONFIGURATIONS
- Common configurations
- Single bus with sectionaliser
- Single main bus with transfer bus scheme
- Dual main and transfer bus
BREAKER AND HALF SCHEME
- Introduction
- Double breaker and double bus scheme
- Main equipment
DESIGN PROJECT
- Background information
- Data
- Substation envisaged
- Design report format
- Design output
SYSTEM STUDIES FOR SUBSTATION DESIGN
- Importance of system studies
- Power system model for studies
- Load flow study
- Power flow in simple radial systems
- Applications of load flow study
INTRODUCTION TO FAULT
- Fault- Definition
- Reasons for fault
- Types and effects of fault
- Human safety
- Limiting the damaging effects of a fault
LIMITING EARTH FAULT CURRENT
- Proper design of system and equipment
- Magnitude of faults
- Calculating system impedance
- Impedance ‘per unit value’
- Per unit impedance of a transformer
- Reduction of impedance diagram
CONCEPT OF BASE KVA
- Overview
- Line impedance
- Conversion examples- Lines and cables
- Importance of asymmetrical fault behaviour
STABILITY STUDIES
- Short circuit study
- Harmonic flow
- Voltage profile and reactive power compensation
- Other calculations
- System study specifications
SUBSTATION EQUIPMENT AND RATINGS
- Choosing main (primary) equipment
- Power transformers (IEC 60076)
- Basic data
- Design options
- Single vs three phase
WINDING CONNECTIONS
- Introduction
- Tertiary winding: Current flow
- Terminal arrangements: MV
- Terminal arrangements: HV
INTRODUCTION TO DISCONNECTORS AND CIRCUIT BREAKERS (IEC 62271)
- Overview
- Types of disconnectors
- Functions and types of circuit breakers
- Ratings and Options for the construction of circuit breakers
- Live tank and dead tank- Basics
- Comparison of HV CB mechanism
DISCONNECTING CIRCUIT BREAKER (DCB)
- Basics of DCB
- DCB with earthing mechanism
- Disconnecting link on the bus bars
- CB interlocking scheme
INSTRUMENT TRANSFORMERS
- Functions of instrument transformers
- Classification of voltage transformers
- Accuracy of VT’s
- Current transformer types
- CT magnetisation curve characteristics
- Optical CT/VT
BASICS OF LIGHTNING ARRESTORS
- Types of surge protection devices
- Metal oxide varistors (MOV)
- Typical arrestor specification
LAYOUT OF SUBSTATION
- Electrical and Safety clearances- Definitions
- Bus bars and connections
- Control interconnections
SPECIFICATION OF FAULT LIMITING REACTORS
- Need for Fault limiting reactors
- Construction of fault limiting reactors
- Possible locations for current limiting reactors
- Other uses of reactors
- Ferranti effect in long lines
- Current limiting reactor specification
POWER FACTOR COMPENSATION
- Overview
- Shunt and series VAr compensation
- Vector relationship between power components
- Calculation of VAr requirement
- Power factor correction
- Capacitor placement in a distribution feeder
REQUIREMENTS OF CAPACITOR BANK – OUTDOOR
- Basic specifications of capacitor bank
- Design considerations
- Principle of Static VAR compensators (SVC)
- Main applications
INTRODUCTION TO HARMONICS
- Definition
- Linear and non-linear load
- Harmonic components- SMPS
- Harmonic characteristics
HARMONIC CONTROL METHODS
- Solutions for neutral overloading
- Overheating of transformers
- Capacitor failures due to harmonics
- Causes of skin effect
- Electromagnetic Interference (EMI)
- Limits of harmonics in a power system
- Analysis of harmonic components
- Harmonic control methods
RECTIFIER CONFIGURATION
- Overview
- 6-Pulse and 12-Pulse rectifier configuration
- Passive filters for harmonic control
- OUTDOOR HARMONIC FILTER INSTALLATION
- Principle of active filter
- Isolation by transformer delta winding
- Integration with PF compensation
OVERVIEW OF MEDIUM VOLTAGE (MV) METAL ENCLOSED SUBSTATION EQUIPMENT
- Application of medium voltage in distribution networks
- Definition of Switchgear
- Switchgear functions
- Applicable IEC standards
- Advantages of Outdoor open type and Indoor metal enclosed type
MV SWITCHGEAR COMPARTMENTS
- Switchgear configurations
- Panel- Single and double bus
- Ring main unit- Schneider RN2C
- Properties of insulation
UTILISATION OF CIRCUIT BREAKER
- Need for circuit breaker
- Types of circuit breaker
- Principle of SF6 circuit breaker
- Vacuum CB interrupter
CIRCUIT BREAKER/SWITCHGEAR RATINGS: INDOOR EQUIPMENT
- Requirements for indoor switchgear equipment
- Special service conditions
- Rated Voltage and Insulation level
- Rated short time withstand current
- Symmetrical and Asymmetrical rating
- Disconnecting switches and Vacuum contactors
- Control, protection and auxiliary power
- CTs and VTs for indoor MV switchgear
CURRENT AND VOLTAGE TRANSFORMERS
- Protection elements
- Cabling in substations
- Ventilation and fire safety
- Layout options and Work clearances
- Arc and fire safety in MV installations
MV SUBSTATION DESIGN AND SPECIFICATIONS
- Sizing of main equipment of MV substations
- Supply to MV substations
- Layout of typical MV indoor substation
- Network connections
- Substation sizing– Main equipment
- HV incoming supply
INTRODUCTION TO SINGLE LINE DIAGRAM
- Dimensions
- Panel space requirements and arrangement
- Safe ingress
OPERATING REQUIREMENTS OF SUBSTATION
- Transformer placement and cell
- Fire containment measures
- Maintenance of transformers
TRANSFORMER FIRE PROTECTION
- Passive and active measures
- Transformer fire hazards
- Battery room requirements and planning
- Sources of auxiliary supply
- Earthing and separate auxiliary transformer
- Diesel generators (DG) back up for auxiliary power
- Cable as a part of building planning
