FUNDAMENTALS OF ELECTRICAL SUBSTATION AND SWITCHYARD DESIGN
Role of substations in an electrical network, types and configurations of substations:
- Networks – an introduction
- Different voltages in a network
- Substations as network nodes
- Substation types based on their position in the network
- Optimising the location of a substation
- Substation options: Outdoor air insulated, GIS, Indoor air insulated
- Configurations of HV substations based on their bus arrangement (typical SLD)
- Data on the industrial loads required for the design of the electrical supply substation
- Load assumptions for residential and commercial consumers
- Environmental issues in the location of a switchyard and mitigation measures
AS:NZS 3000-2007
Power-system protection has become increasingly important as a way of protecting electrical power systems from faults through the isolation of faulty parts from the rest of the electrical network. The objective of a protection scheme is to keep the power system stable by isolating only the components that are under fault, whilst leaving as much of the network as possible still in operation. Thus, protection schemes must apply a very pragmatic and pessimistic approach to clearing system faults.
This course is designed to help students to understand the principles of protective systems and their application in real life.
Most important of all, they can improve the safety of the site by making better decisions on system protection.
POWER ELECTRONICS
Power electronics generally deals with the conversion of electric power. An expert knowledge on the characteristics and operation of power electronic circuits is must for a technical staff to be efficient while working on high power applications. However the major concern in the power electronics area is switching losses during switch ON/OFF which will reduce the efficiency and performance of the system. By involving certain methods, switching losses can be reduced thereby improving the overall efficiency of the system.
Participants can use the skills and gain in-depth knowledge from this work shop on the emerging applications of semiconductor devices that offer higher efficiency.
This course is designed to introduce students to power electronic converters and their recent trends and applications in various fields.
POWER SYSTEM PROTECTION
Power system protection is one of the most important aspects of the electrical power industry. Without protection, any stem fails. So it is imperative that safety and protection be given utmost importance to avoid catastrophes.
This course is designed to help students to understand the fundamentals of electric power protection, so that they can choose appropriate protective devices/measures for different components, interpret different protection systems in their plant and also detect short-comings. Simple calculations can be performed too.
Most important of all, they can improve the safety of the site by making better decisions on system protection.
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
ROLE OF SUBSTATIONS IN AN ELECTRICAL NETWORK, TYPES AND CONFIGURATIONS OF SUBSTATIONS
- Networks – an introduction
- Different voltages in a network
- Substations as network nodes
- Substation types based on their position in the network
- Optimising the location of a substation
- Substation options: Outdoor air insulated, GIS, Indoor air insulated
- Configurations of HV substations based on their bus arrangement (typical SLD)
- Data on the industrial loads required for the design of the electrical supply substation
- Load assumptions for residential and commercial consumers
- Environmental issues in the location of a switchyard and mitigation measures
SYSTEM STUDIES REQUIRED FOR FINALISING EQUIPMENT RATINGS
- Load flow study (active/reactive loads)
- Short circuit study
- Harmonic flow
- Voltage profile and reactive power compensation
- Stability study
- Note: The objective/relevance of each of these studies to the substation equipment selection and specifications, the inputs required and outputs expected will be covered in this section. A broad overview of the studies will be provided without going into the actual calculations involved.
OVERVIEW OF SWITCHYARD EQUIPMENT AND THEIR ORDERING SPECIFICATIONS
- Main (primary) equipment
- Busbars
- Disconnectors
- Circuit breakers
- Instrument transformers
- Lightning arrestors
- Power transformers
- Structures
- Layout options
- Sectional and Safety clearances and their influence on the layout
- Design of busbars (strung/tubular) and interconnections between equipment
- Interconnecting cables and use of marshalling kiosks
PROTECTION DESIGN FOR SUBSTATION
- Brief overview of protection
- Over current protection
- Protection coordination
- Protection of transformers
- Busbar protection
- Feeder protection
- Current transformers requirements for protection
- Equipment requirements for substation automation
- PLCC applications in protection and communication
- PLCC hardware and integrating them with the switchyard equipment
SUBSTATION EQUIPMENT FOR FAULT LIMITING, PFC AND HARMONIC CONTROL
- Need for and application of:
- Fault limiting reactors
- Power factor compensation equipment
- Static VAR compensators
- Harmonic filters
- Equipment design and selection of ratings
- Layout of these equipment in a switchyard
EARTHING SYSTEM AND LIGHTNING PROTECTION OF SWITCHYARDS
- Basics of functional and protective earthing
- Touch and step voltages in substations
- Earth grid and its role in safety
- Switchyard fence-why it should be a part of the earth grid
- Design of earth grid-basic considerations in conductor sizing and mesh spacing
- Pros and cons of including the control building within the switchyard earth grid
- Earth mat laying and welding
- Safety mesh at operating points
- Role of gravel layer in safety
- Transferred voltage hazards
- Planning isolation of outgoing services to avoid transfer voltage
- Basics of lightning and hazards
- Role of shield wire and lightning masts
- Typical configurations of lightning protection of switchyards
- Analysis of hazard using cone of protection and rolling sphere methods
- Selection of lightning arrestors-Types, class and ratings
SWITCHYARD CONTROL AND INTERLOCKING
- Dc power requirements for switchyard equipment
- Dc equipment configuration and specifications
- Dc distribution for switchyard equipment
- Battery calculations basis
- Space planning and related facilities for a battery installation
- Ac auxiliary power for switchyard systems-loads which require ac power
- Possible source options
- Ac auxiliary distribution for switchyard equipment and support systems
- Control scheme of disconnectors and circuit breakers
- Control interconnection approach
- Use of optical fibre-based control scheme
- Role and location of marshalling kiosks in different bays
SWITCHYARD-FACILITY PLANNING
- Site preparation, levelling
- Earth resistivity measurement and its role in design verification
- Civil works such as equipment foundations, cable trenches, control building, storm drains, transformer oil collection pit
- Structures and their design requirements
- Substation fence and physical security
- Surveillance
- Planning water requirements and supply arrangement
- Fire protection, lighting and ventilation of control room and other equipment
AS/NZS 3000-2007 - INTRODUCTION
- Basics of energy sources
- Components of electrical system
- Need for protection: Impact of types of loads and earthing on protection types
EARTHING AND ITS IMPORTANCE IN SAFETY
- Earthing – Definitions and its types
- Solidly earthed system
- Earth fault current flow
- Earthing arrangements and earthing conductors
- Importance of protective earthing
REGULATIONS OF AS/NZS 3000-2007
- Need for the regulations
- Regulations for protection against various electrical hazards
- Features of AS/NZS 3000
- Special electrical installations
SCOPE AND FUNDAMENTAL SAFETY PRINCIPLES
FUNDAMENTAL PRINCIPLES OF PROTECTION
- Methods of Protection against various hazards
- Control and isolation
- Design of an electrical installation
- Selection and installation
SELECTION AND INSTALLATION OF SWITCHGEAR AND CONTROLGEAR
- Common requirements of switchgear and controlgear
- Control of electrical installation
- Isolation switch requirements
- Emergency switching and emergency stopping
- Fault protection
- Overcurrent protection
GENERAL PROTECTION ARRANGEMENT OF SWITCHGEAR AND CONTROLGEAR
- Overload protection devices
- Selection of protective device
- Protective device coordination
- Residual Current Devices(RCDs)
- Devices for isolation and switching
- Switchboards
SELECTION AND INSTALLATION OF WIRING SYSTEMS
- Basic requirements of wiring systems
- Protection of wiring systems
- Cable sizing and colours
- Electrical connections
- Segregation
REQUIREMENTS OF UNDERGROUND WIRING
- Suitability and protection
- Categories of Underground wiring system-Installation requirements
- Aerial Wiring conductors
- Earth Sheath Return System
SELECTION AND INSTALLATION OF APPLIANCES AND ACCESSORIES
- Appliances and accessories- Selection and installation
- Protection against thermal effects
- Electrical equipment- connection
- Lightning installation
- Socket-outlets and polarization
- Lightning equipment and accessories
- Lightning point- Smoke detectors
- Motors, transformers, capacitors and liquid dielectrics
EARTHING ARRANGEMENTS AND EARTHING CONDUCTORS
- Basic features and need for earthing
- Earthing selection and installations
- Common earthing methods
- Earthed and Unearthed systems
- Importance of Protective and functional earthing
MULTIPLE EARTHED NEUTRAL SYSTEMS(MENs)
- Components of MEN system
- Protective conductor
- MEN earthing system – Connections
EARTHING CONDUCTORS- MATERIAL, SIZE AND INSTALLATION METHODS
- Specific requirements and installations
- Equipotential bonding
- Earth Fault Loop Impedance
- Earth Fault Current Calculation
- Other earthing arrangements
CABLE SELECTION PROCEDURES
- Steps to find low voltage and high voltage installations
- Basic inspection procedures
- Tests for low voltage and high voltage installations
DAMP SITUATIONS
- Classification of zones
- Degree of protection in communal baths/showers
- Swimming pools and Spa pools
- Zone dimensions for Spa pools and tubs
- Sauna heaters
- Refrigeration rooms
- Hosing down areas
SPECIAL ELECTRICAL INSTALLATIONS
- Safety services
- Fire and smoke control equipments, supply systems
- Electricity generation systems
- Protection by electrical separation
- Extra low and high voltage installations
- Hazardous areas
- Specific electrical installation standards
VERIFICATION
- Visual inspections
- Basic checks on various systems
- Sequence of tests
- Mandatory tests
- Tests on RCDs
ELECTRICAL INSTALLATIONS- VERIFICATION GUIDELINES
- Test detailed
- Equipment needed
- Basic checks
- Measurement of earth electrode resistance
- Measurement of touch voltage
ELECTRICAL INSTALLATIONS- PERIODIC VERIFICATION
- Objective and scope
- Basic verification requirements
- Verification by basic visual inspection
- Verification by visual inspection and limited testing
- Verification by visual inspection and full testing
CIRCUIT PROTECTION GUIDE
- Circuit arrangements
- Protection against overcurrent
- Principles of Automatic Disconnection
- Earth Fault impedance
- Impedance for calculations
CIRCUIT ARRANGEMENTS
- Determination of circuit current for consumer mains, submains and final subcircuits (Maximum Demand)
- Cable selection based on current-carrying capacity and voltage drop
- Coordination of current ratings of circuit cables and protective devices
- Cable installation guides
REQUIREMENTS IN NATIONAL BUILDING CODES
- Provisions in the Building Code of Australia (BCA) and New Zealand Building Code(NZBC)
INSTALLATION OF SURGE PROTECTIVE DEVICES
- Selection and installation of SPDs
- Overcurrent protective device
- Connecting conductors
- Surge protective earthing and bonding
DEGREES OF PROTECTION OF ENCLOSED EQUIPMENT
WS CLASSIFICATION OF WIRING SYSTEMS
- Wiring systems classification
- Specific Wiring Systems
- Wiring systems adopted
- Application of wiring systems
COMPONENTS FOR ALTERATIONS ADDITIONS AND REPAIR
- Applications
- Protective device ratings
HIGH VOLTAGE ELECTRICAL INSTALLATIONS
- Circuit control and protection
- Equipment requirements
- Substations
- Electrical equipment with liquid dielectrics
- Safety signs
- HV System Testing
INTRODUCTION TO POWER ELECTRONIC CIRCUITS AND DEVICES
- Basic Definitions
- Bistable Switching
- Power Diodes
- Commutation losses of Power Thyristors
- Diode Rectifier AC and DC Current
- Operating principle of Line Commutated Thyristor Rectifier
BASIC PRINCIPLES OF INVERTER AND THYRISTOR
- General purpose Inverter
- Principles of Gate Commutated Inverters
- Modulation Techniques of PWM Inverter
- Switching configurations of 3-phase PWM Inverter
- GTO Thyristors
- Field Controlled Thyristors
- Power Ratings of Bipolar Junction Transistor
- Applications of Field Effect Transistors
- Symbol, Features and Advantages of Insulated Gate Bipolar Transistor
- Future power semiconductor devices development direction
INTRODUCTION TO SWITCH MODE POWER SUPPLIES
- Power supply efficiency
- Dissipative Power Supplies : Series
- Implications of Power Loss
- Advantages of Switching-Mode Power Supplies
- Switching regulator
ISOLATED AND NON-ISOLATED TOPOLOGIES OF CONVERTER
- Operating principle of Buck and Boost Regulator
- Construction of Fly back Converter
- Forward Converters
- Circuit arrangement of Push-Pull Converters
- Operation of Half Bridge and Full Bridge Converter
SWITCH MODE POWER SUPPLY DESIGN 1 AND 2
- Block Diagram of Switch Mode Power Supply
- 115V and 230V operation of Voltage doubler
- Component selection and design criteria
- Input Protective Devices
HIGH FREQUENCY TRANSFORMERS
- Criteria for the selection of magnetic component design
- Ferrite core material for high-frequency power transformers
- Faraday’s law of electromagnetic induction
- Hysteresis loop
- Typical magnetization curve
- Basic transformer theory
WINDING TECHNIQUES
- Planar winding structure
- Meander planar winding
- Co-axial winding structure
- Losses and Temperature rise
- Switch Mode Power Supply block diagram- Output section
SWITCH MODE PSU DESIGN 2
- Output Rectification and Filtering
- Power Rectifier characteristics
- Motorola Rectifier Product Portfolio
- Transient over-voltage suppression
- Switch protection circuits
- Output Power Inductor and Capacitor Design
- Application of Magnetics Molypermalloy Powder ( MMP)
INTRODUCTION TO HEAT-SINKING
- Objective
- Thermal equation
- Path of thermal conductivity
- Thermal resistance
- Heat sink selection
IC PWM CONTROLLERS
- Voltage doubler- 115V Operation
- Use of PWM Controller in SMPS
- Pulse-width modulator block diagram and comparator signals
- A discrete PWM control circuit for a fly-back switching power supply
- Methods of Control
- UC3825 block diagram
- High Speed Complementary Blocks
SWITCH MODE POWER SUPPLY CONTROL AND STABILITY
- Transfer Function of various converters
- Criteria for Stability
- Methods of SMPS control
- Design Compensation Networks
- Loop Stability Measurements
INTRODUCTION TO VARIABLE SPEED DRIVES
- Need for Variable Speed Drives
- Fundamental principles- Definitions
- Torque-Speed curves
- Variable Speed-Energy conservation
- Types of Variable Speed Drives
- Principles of DC and AC Variable Speed Drive
3-PHASE INDUCTION MOTORS
- Introduction
- Construction and operating principles of Induction motors
- Equivalent Circuit of AC Motor
3-PHASE INDUCTION MOTOR PERFORMANCE AND EFFICIENCY
- Performance, Efficiency and Mechanical Output Power
- Torque-Speed curve
- Rating of AC Induction Motors
- Methods of Starting and Selection of Motor
PROTECTION OF AC CONVERTERS
- Input Phase Imbalance
- DC Bus Under-voltage and Over-voltage
- Over- Current Protection
- Output Earth Fault Protection
- Over Temperature Protection
AC MOTOR PROTECTION
- Motor Thermal O/L Protection
- Electric Motor Protection
- Winding Thermostats
- 2-Wire and 3-Wire RTDs
CONTROL SYSTEMS FOR AC VARIABLE SPEED DRIVES
- Overall Control System
- DC bus Pre-charging circuit 1 and 2
- PWM Rectifier for AC Converters
- Variable Speed Drive control loops
- AC Variable Speed Drives
VECTOR CONTROL DRIVES
- Flux-Vector Control
- Sensor less Vector Control Drives
- Field Oriented Flux-Vector Drives
- Hall Effect Sensor
- Incremental Rotary Encoders
SELECTION OF AC CONVERTERS
- Introduction
- Basic Selection Procedure of AC Variable Speed Drive
- Torque Loadability Curve
- Nature of the Machine load
- Variable Torque Loads- Pumps and Fans
- Constant Torque Loads- Conveyors
- Requirements for Starting and Stopping
INTRODUCTION TO TYPES OF BRAKING
- Basic principle of DC Braking
- Dynamic Braking
- Methods of Regenerative Braking
ELECTROMAGNETIC COMPATIBILITY
- Electrical Interference
- Sources of Harmonic currents
- Power Electronic Converters
- Mains current harmonics- DC and AC PWM DRIVES
REDUCTION OF HARMONICS
- Multi Pulse Converters
- Problems with HF PWM Switching
- Motor side filter
REQUIREMENTS OF AC VARIABLE SPEED DRIVE SYSTEM
- De-Rating for Temperature and Altitude
- Main Cable Connections
STOP/START Control of AC drives
- Contactor- Main supply side and motor side
- Mounting in Metal Enclosures
- PLC Control wiring
- General SMPS Troubleshooting approach
RELAYS
- Inverse, Definite Minimum Time (IDMT) relay – construction principles and setting
- Calculation of settings – practical examples
- New era – modern numerical relays and future trends
FEEDER PROTECTION
- Cables
- Pilot wire differential
- Overhead lines
- Distance protection (basic principles, characteristics, various schemes)
TRANSFORMER PROTECTION
- Phase shift, magnetising in-rush, inter-turn, core and tank faults
- Differential and restricted earth fault schemes
- Buchholz relay, oil and winding temperature
- Oil – testing and gas analysis
SWITCHGEAR (BUSBAR) PROTECTION
- Requirements, zones, types
- Frame leakage, high, medium and low impedance schemes, reverse blocking
NEED FOR PROTECTION
- Selectivity, stability, sensitivity, speed
- Reliability, dependability, security
FAULT TYPES AND THEIR EFFECTS
- Active, incipient, passive, transient, asymmetrical etc
- Phase and earth faults
SIMPLE CALCULATION OF SHORT CIRCUIT CURRENTS
- Revision of simple formulae
- Calculation of short circuit MVA and fault currents
- Worked examples
SYSTEM EARTHING
- Solid, impedance, touch potentials etc
- Effect of electric shock on human beings
- Earth leakage protection
PROTECTION SYSTEM COMPONENTS INCLUDING FUSES
- History, construction, characteristics
- Energy, let-through, application
INSTRUMENT TRANSFORMERS
- Current transformers: construction, performance, specification, magnetisation, curves etc
- Voltage transformers: types, accuracy, connections
CIRCUIT BREAKERS
- Purpose and duty, clearance times, types etc
TRIPPING BATTERIES
- Battery types, chargers, maintenance, D.C. circuitry
PRACTICAL DEMONSTRATION SESSION
- Including simple fault calculations, relay settings and checking a current transformer, magnetising curve etc.
APPLICATIONS CO-ORDINATED BY TIME GRADING
- Problems in applying IDMT relays
UNDERGROUND MINE DISTRIBUTION PROTECTION
- Earth leakage protection, pilot wire monitor, earth fault lockout, neutral earth resistor monitor
- Selective co-ordination by current grading
PRINCIPLES OF UNIT PROTECTION
- Differential protection – basic principles
MOTOR PROTECTION
- Thermal overload, time constants, early relays
- Starting and stalling conditions
- Unbalanced supply voltages, negative sequence currents, de-rating factors
- Phase-phase faults
- Earth faults – core balance, residual stabilising resistors
GENERATOR PROTECTION
- Stator and rotor faults
- Overload and over-voltage
- Reverse power/unbalanced loading
- Loss of excitation and synchronism
- Typical protection scheme for industrial generators
MANAGEMENT OF PROTECTION
- Routine testing, annual testing, investigation and performance assessment, up-grading
- Organisation, training, records, access planning
