electrical power system for non technical employees
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ELECTRICAL POWERSYSTEMS FOR
NON-TECHNICAL
EMPLOYEES
TEXTBOOK
TECHNICAL SHORT COURSE
TSC-GC07
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TABLE OF CONTENTS
TSC-GC07 Electrical Power Systems for Non-Technical Employees, Textbook 3
ELECTRICAL POWER SYSTEMS
FOR NON-TECHNICAL EMPLOYEES
TSC-GC07
Textbook
TABLE OF CONTENTS
Lesson Description Page
Course Overview……………………………………………………. 5
1 Introduction to Power Systems……………………………………… 9
2 Main components of Electrical Power Systems…………………… 29
3 Industrial Training Program ITP Crafts…………………………… 65
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COURSE OVERVIEW
TSC-GC07 Electrical Power Systems for Non-Technical Employees, Textbook 5
ELECTRICAL POWER SYSTEMS
FOR NON-TECHNICAL EMPLOYEES
TSC-GC07
Textbook
COURSE OVERVIEW
OVERVIEW
This course familiarizes non-technical employees of SEC with electrical terminology,
equipment and different crafts in Generation, Transmission and Distribution systems.
DURATION
Two days
CONTENT
This two days course is divided into three (3) lessons of instruction, as follows:
Introduction to Power Systems Main Components of Electrical Power Systems
Industrial Training Program ITP Crafts
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PACING SCHEDULE
TSC-GC07 Electrical Power Systems for Non-Technical Employees, Textbook 7
ELECTRICAL POWER SYSTEMS
FOR NON-TECHNICAL EMPLOYEES
TSC-GC07
Textbook
PACING SCHEDULE
Lesson Description Hours
1 Introduction to Power Systems…………………………………. 6
2 Main components of Electrical Power Systems………………… 4
3 Industrial Training Program ITP Crafts………………………… 2
Total 12
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9
LESSON 1
INTRODUCTION TO
POWER SYSTEMS
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LESSON OVERVIEW
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 11
LESSON 1
INTRODUCTION TO SEC SYSTEMS
OVERVIEW
This lesson familiarizes the participants with different generation, transmission and
distribution systems.
OBJECTIVES
Upon completion of this lesson, the participants should be able to:
Identify Generating Sets and Network Generation Plants:
- Steam Generation Plants
- Gas Turbine Generation Plants
- Combined Cycle Generation Plants
- Internal Combustion or Diesel Engine Plants
- Alternative Energy Power Plants
Identify Transmission Substations Network:
- The Electrical Grid
- Voltage Levels
-
Sub Transmission
- Bulk Supply Point
Identify Distribution Substations:
- Primary Distribution
- Secondary Distribution
- Load
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INFORMATION SHEET
14 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
1.2 GENERATION OF ELECTRICITY
Electricity is a type of energy that can build up in one place or flow from one
place to another. When electricity gathers in one place , it is known as static
electricity (the word “static” means something that does not move); electricity
that moves from one place to another is called electrical current.
When we move a conductor through a magnetic field, or move the magnetic field
relative to the conductor, it causes a current to flow in the conductor.
Let us suppose that the rectangular coil ABCD is initially in the horizontal
position. As the coil rotates in the anticlockwise direction between the poles N
and S of the magnet, side AB of the coil moves down cutting the magnetic lines
of force near the N-pole of the magnet and side CD moves up, cutting the lines of
force near the S-pole of the magnet. Due to this, induced current is produced in
the sides AB and CD of the coil. Thus the induced currents in the two sides of the
coil are in the same direction and we get an effective induced current in the
direction BADC. Due to this, brush B1 becomes the positive pole and brush B2
becomes the negative pole of the generator. Then, the current is induced in the
coil. This current can be used to run various electrical appliances (Fig. 1-1).
Magnets + Conductors + Motion = Electric Current
Fig. 1-1 Principle of Electric Generator
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 15
1.3 OVERVIEW OF ELECTRICAL NETWORK
The electrical power network includes generation plants (steam, gas and
combined), transmission substations and distribution substations to transfer the
Electric power from generation plants to the residential, commercial and
industrial loads, as shown in Fig. 1-2 and Fig. 1-3.
Fig. 1-2 Electrical Power Network
In Saudi Electricity Company (SEC), there are many types of power generating
plants: steam, gas, combined cycle and diesel engine power plants. Steam power
plants are usually located near the sea for cooling purposes. For example,
Ghazlan and Qurayyah power plants (Steam) are located on Arabian Gulf, while
Shoaiba and Rabegh power plants are located on Red Sea. Other types of power
plants like gas power plants are installed in the areas where water sources are not
available.
Fig. 1-3 Transmission Substation
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INFORMATION SHEET
16 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
1.4 GENERATION
Diesel engines, gas and steam turbines are the most commonly used prime
movers for the generation of electrical power. Additionally, the steam turbine can
be employed in combination with gas turbine for combined cycle operation. The
following describes the basic operation of each of these prime movers in relation
to its associated power-generating scheme. Each generator in a power plant is
driven by its own prime mover (also called driver). A turbine is a prime mover.
A motor is also a prime mover. Each generator is attached to its own prime mover
to make up a single unit or a set. The term generating set includes both a
turbine and a generator.
The electrical power output is proportional to the mechanical power input. Agenerator design capability (or maximum output or maximum load) is expressed
in electrical units, Mega-Watts (MW) or mechanical units, Horse-Power (HP).
For example, one HP of mechanical energy equals 746 Watts of electrical
energy. Thus, a generator rated 10 Mega-Watts (10 MW) maximum output
requires a diesel engine or gas turbine rated at (10000000/746) HP or 13400 HP
to drive it (plus about 10% allowance for energy used in overcoming friction, air
resistance and producing unavoidable heat). That is about 14500 - 15000 HP, as
shown in Fig. 1-4.
Fig. 1-4 Generation Block Diagram
TYPES OF GENERATION POWER PLANTS
Electric power is generated by different types of power plants for residential,
industrial and commercial customers, as follows:
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 17
STEAM GENERATION PLANTS
The steam is created by a boiler, where pure water passes through a series of tubes to
capture heat from the firebox and then boils under high pressure to become
superheated steam. The heat in the firebox is normally provided by burning fossil fuel,
coal, fuel oil or natural gas, as shown in Fig. 1-5.
Fig. 1-5 Essential Components of Steam Electric Power Generation Plants
GAS TURBINE GENERATING PLANTS
The gas turbine generating plants convert heat energy into electric energy. In the gas
turbine, air is compressed by the compressor into the combustion chambers where it
mixes and burns with the fuel. The combustion gases then flow through turbine
section producing driving power as they expand in the stages of the turbine driving the
generator. The fuel can be either gas type or liquid fuel. In case of liquid gas, a
process of purification and atomization takes place before injecting it to the
combustion chamber. Fig. 1-6 shows, schematically, the components of a gas turbine
plant. With the increasing availability of natural gas (methane) and its competitive
price, prime movers based on the gas turbine as developed for aircraft are being
increasingly used. Because of the high temperatures obtained by gas combustion, the
efficiency of a gas turbine is comparable to that of a steam turbine, with the additional
advantage that there is still sufficient heat in the gas-turbine exhaust to raise steam in a
conventional boiler to drive a steam turbine coupled to another electricity generator.
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INFORMATION SHEET
18 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
The advantages of gas turbine plant are the fast start up and shut down (5-10 min.),
faster installation because of its modular nature and factory supplied units, and its
ability to run on oil from local storage tanks if the gas supply is interrupted. Modern
installations are fully automated and require only a few operatives to maintain 24 hr
running or to supply peak load, if needed.
ESSENTIAL COMPONENTS OF GAS TURBINE PLANT
1.
Compressor
2. Combustion chamber
3. Gas turbine
4. Generator
Fig. 1-6 Gas Turbine Plant Construction
COMBINED CYCLE POWER PLANT
The gas turbine's major disadvantage is its low efficiency of around 25-35%.
However, this can be significantly improved by the use of a Waste Heat Recovery
Boiler (WHRB) or Heat-Recovery Steam Generator (HRSG). The steam from
WHRB or HRSG is directed to a steam turbine generator where it is used to power the
steam turbine Gen-Set. This is known as a Combined-Cycle Gas-Turbine (CCGT)
plant. Combined efficiencies, now being achieved, are between 50 and 60 % with
live steam temperature between 420 °C and 580 °C. By capturing the waste heat of the
gas turbine in a Combined Cycle Power Plant and putting it to work, the overall
thermal efficiency of the plant is increased. In a typical cogeneration plant, electric
power is generated but some of the steam from the WHRB or HRSG is used for
process heat.
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 19
The combined-cycle power plant combines the steam turbine and gas turbine
thermodynamic cycles by using heat recovery boilers to capture the energy in the gas
turbine exhaust gases for steam production to power a steam turbine, as shown in the
Fig. 1-7 for "Combined-Cycle Cogeneration". Process steam can be also provided for
industrial purposes.
Fig. 1-7 Combined Cycle Power Plant
INTERNAL COMBUSTION ENGINE (ICE) PLANTS OR DIESEL
ENGINE PLANTS
The diesel engines are piston cylinder engines that burn diesel fuel and drive
generators coupled to the engine by the engine crank shaft. These types of plants are
used to serve remote villages that cannot be served directly from the grid. Also, these
plants are usually mobile type. Fig. 1-8 shows a typical I.C.E. generating unit.
Fig. 1-8 Diesel Engine Coupled Directly To the Generator
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INFORMATION SHEET
20 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
COMPARISON BETWEEN STEAM, GAS AND DIESEL POWER PLANTS
POWER
PLANT
ITEM
STEAM GASCOMBINED
CYCLE
Overall Efficiency Around 35-47% Around 25-35% Around 50-60%
By fuel(Fossil) Crude oil-
natural gas(Fossil) Crude oil-natural gas
(Fossil) Crude oil-
natural gas
By prime mover Steam turbine Gas turbineSteam turbine
Gas turbine
Main Component
- Boiler
- Turbine
- Condenser
- Feed pump
- Compressor
- Combustion Chamber
- Turbine
- Gas Turbine
- Heat Recovery Steam
Generator
- Steam Turbine
Site conditions Need cooling water
requirements
No cooling water
requirements
Need cooling water
requirements
Generation Of
Electrical PowerAround 1000MW Around 150 MW Around 500Mw
Fast load-pickup
ability3-12 Hr 3-8 Min
3-8 Min for Gas
Turbine only
3-12 Hours for full load
Operation and
Maintenance
Costs
Max operation and
maintenance costs
Minimum operation and
maintenance costs
Medium operation and
maintenance costs
Installation CostHigh installation
costsLow installation costs High installation costs
Installation TimeLong delivery time
2 to 4 years
Short deliver time
1 to 2 years
Long deliver time
around 2-4 years
Exhaust Gas
Temp (0C)
Around 110oC Around 550oC Around 110oC
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 21
1.5 OTHER TYPES OF GENERATION POWER PLANTS
NUCLEAR POWER PLANTS
In nuclear-powered generating units, the boiler is replaced by a reactor in which the
fission of uranium is used to generate heat. These plants rely on uranium, a type of
metal that must be mined from the ground and specially processed. Fuel rods
containing uranium are placed next to each other in a machine called nuclear reactor.
The reactor causes the uranium atoms to split and in doing so, they release a
tremendous amount of heat. Water is boiled by nuclear fission in the nuclear reactor.
As a result, water turns to steam to drive a steam turbine.
HYDRO GENERATION PLANTS
The hydroelectric power generation plant, as shown in Fig. 1-9, operates on the
principle of potential energy contained in water reservoir at a height. The height is
referred to as the head. The maximum power obtained from a hydro plant may be
computed by multiplying the head, water density, and volumetric flow rate. These
types of generation power plants being impractical are not used in SEC.
Fig. 1-9 Hydro Generation Plants
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 23
GEOTHERMAL ENERGY
A geothermal power plant is pretty much a steam power plant, since what comes out
of the earth is steam. Rainwater soaks into the ground and goes down, far enough until
it reaches a region, which is really hot (in Hawaii, that's about 6000 feet). A well is
drilled; the steam comes out, spin a turbine. By the time the steam has gone through
turbine, it has cooled off and become warm water. It is then re-injected into the
ground. Complete process is shown in Fig. 1-12.
Fig. 1-12 Geothermal Power Plant
1.6 TRANSMISSION
The purpose of electrical transmission network is to transfer electricity from the
generation plant to the user. Power plants are connected together by transmission lines
and switchyard.
ELECTRICAL NETWORK
A network is an advanced type of electrical power system. An electrical networkconsists of several power plants. They are connected together by transmission
lines (or cables) and switchgear. Each power plant in the network acts as part of a
"team" instead of working alone. The terms "electrical power system" and
"electrical power network" are used to describe this te rm.
A power system with all generating stations and all load areas connected in parallel
may be represented by a theoretical diagram illustrated in Fig. 1-13. Here, the network
is shown as a kind of "reservoir" of electrical power with generating sations "a", "b",
"c", "d" pumping power into the reservoir and load areas A, B, C, D, consuming power.
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INFORMATION SHEET
24 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
Fig. 1-13 Electrical Network Areas Block Diagram
NETWORK ACTION
In Fig. 1-14, the large load area B (20MW) is fed from station b, with four generators;
while load area C (5MW) is supplied by the single unit in station "c", "a" producing
(15MW) with 12MW supplying area A, 1MW to isolated area E , and 2MW shared
with area B .Note that area B requires 20 MW but station "b" can produce a maximum
of only 18 MW, as two of the generating sets are "off-line".
Power plant "c" (one generator) is also off-line, so plant "d" (four operational
generating sets is simultaneously supplying its own area D (23MW) plus area C and
area F (5MW + 2MW). At this particular time, there is zero flow in the transmission
line between plants "a" &"c". Plant "g" is a small, single-generator "emergency"
station, which can be put on-line to help out during abnormal conditions. The power
plants in a network can supply loads to anywhere in the network. But it is easier and
cheaper to supply loads to the local area. So plants are located near the majority of
their users or its principal load area. The power plant normally supplies the load to all
users in its area but there is a need to be able to transmit power over long distances.
Fig. 1-14 Power Flow in a Theoretical Network
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 25
LONG DISTANCE TRANSMISSION LINES SERVE TWO PURPOSES
1. Supply power to isolated secondary load areas.
2. Transfer electrical power between power plants.
The transmission of power must be accomplished over long distances most
economically and safely as possible.
THE ELECTRICAL GRID
The electrical grid involves many generation plants. The grid has to be an economical
and reliable system, which has reduced the need for additional stand-by generating
units. Also, the grid system is more reliable in satisfying the peak load, which takes place for several hours at particular times of the day. The grid system allows power
plants to work as a team. Switching and transmission substations connect the
generators of the power plant to the transmission lines. Fig. 1-15 shows the
components and the layout of these substations, which are found in the backyard of
the power plant. This power plant substation is called switchyard.
Fig. 1-15 Layout of Substation in the backyard of the power plant
VOLTAGE LEVELS
Voltage levels for transmission network are 380 kV, 230 kV, 115 kV and 69 kV.
Electric power is generated at a voltage level of 13.8 kV. A step-up power
transformer is used to raise the generation voltage up to the transmission voltage.
To protect the system against any failure, nearly all circuits are connected to the
system through circuit breakers that may trip open automatically on fault occurrence.
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 27
SECONDARY DISTRIBUTION
This is the part of the system through which the power finally reaches the most
largest load customers, except for the industries and other larger-load consumers.
Secondary distribution feeders are mainly the Underground Cable (UG) between
the Low Voltage (LV) panel and the Minipillar (MP).
INDUSTRIAL CUSTOMERS
Small industrial customers are served directly by the primary feeders, or possibly
from the sub-transmission system. Large industrial customers are fed directly from
the sub-transmission system, and very large industrial customers may be served
from the transmission system.
1.8 LOAD
The amount of electrical power needed or demanded by the user at any particular
moment of time is usually referred to as Load. The load can vary a great deal from
hour to hour, from day to day and from one part of the year to another part. For
example, in the evening more power is used for lighting and cooking. On holidays,
less power is used by industry and in very hot weather power is used more for airconditioning, ..etc.
Before installing generators, it is necessary to know how much electricity is likely to
be needed by the user, as in the following example. If the maximum predicted load (or
estimated peak demand) for electrical power by the village is taken as 10 MW, the
generating capacity of the power plant MUST not be less than 10 MW.
SUMMARY
Electrical power network includes generation plants (steam, gas and combined),
transmission substations and distribution substations to transfer the power from
generating plants to the (residential, industrial and commercial).
Diesel engine, gas and steam turbines are the more commonly used prime
movers for the generation of electrical power.
Diesel engine is an internal combustion engine that uses diesel fuel instead of
gasoline.
The major disadvantage of gas turbine is low efficiency of around 25-35%.
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INFORMATION SHEET
28 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
Steam power station is a power plant in which the prime mover is steam driven.
Water is heated, turns into steam and spins a steam turbine, which drives an
electrical generator.
The distribution substations include two types - primary distribution and
secondary distribution.
Sub-transmission usually is designated as part of the system between the
transmission and the distribution systems.
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LESSON 2
MAIN COMPONENTS OFELECTRICAL POWER
SYSTEMS
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LESSON OVERVIEW
TSC-GC07 Electrical Power System for Non-Technical Empolyees,Textbook 31
LESSON 2
MAIN COMPONENTS OF ELECTRICAL POWER SYSTEMS
OVERVIEW
This lesson familiarizes the participants with the main mechanical and electrical
components in generation, transmission and distribution systems.
OBJECTIVES
Upon completion of this lesson, the participants should be able to:
Recognize the main electrical and mechanical components:
PART I MAIN MECHANICAL COMPONENTS
- Major components of the steam turbine
- Major components of gas turbine
- Major components of combined cycle
PART II MAIN ELECTRICAL COMPONENTS
Power system components
- Generation components
- Transmission components
- Instrumentation & monitoring systems
- Power system protection
-
Power system communication- Distribution system
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 33
PART I MAIN MECHANICAL COMPONENTS
2.1 STEAM POWER PLANT MAJOR COMPONENTS
BOILER
Once water is inside the boiler or steam generator, the process of adding the latent
heat of vaporization or enthalpy is underway and the boiler transfers energy to the
water by the chemical reaction of burning some type of fuel (natural gas, solar, coal
and nuclear).
The efficiency of this conversion is around 90 %.
BOILER COMPONENTS
Fig. 2-1 Boiler Furnace Components
Referring to Fig. 2-1:
- Furnace
- Economizer
- Down comers
- Water wall (up riser)
- Drum
- Superheater
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INFORMATION SHEET
34 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
STEAM TURBINE
The steam turbine-driven generators have auxiliary systems enabling them to work
satisfactorily and safely, as shown in Fig. 2-2. The steam turbine generator being
rotating equipment generally has a heavy, large diameter shaft. The shaft, therefore,requires not only support but also has to be kept in position while running. To
minimize the frictional resistance to the rotation, the shaft has a number of bearings.
Oil lubrication is provided to further reduce the friction between the shaft and the
bearing surface and to limit the heat generated.
MAJOR COMPONENTS OF STEAM TURBINE
- Turbine nozzle
-
Turbine blades- Turbine casing
- Turbine rotor
- Bearings
- Turning gear
- Atmospheric relief diaphragm
Fig. 2-2 Steam Turbine Components
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 35
CONDENSER
The surface condenser is a shell and tube heat exchanger in which cooling water
circulates through the tubes. The exhaust steam from the low pressure turbine enters
the shell where it is cooled and converted to condensate (water) by flowing over thetubes, as shown in the Fig. 2-3. Such condensers use vacuum pumps for continuous
removal of air and gases from the steam side to maintain vacuum.
Fig. 2-3 Surface Condenser
FIN-FAN COOLERS
two types of fin-fan cooler designs are generally used: Forced Draft and Induced
Draft, as shown in Fig. 2-4.
Fig. 2-4 Draft Fin-Fan Coolers
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INFORMATION SHEET
36 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
Fig. 2-5 and table 2-1 show the main circulating flows in greater detail.
DESCRIPTIONITEM
Boiler Circulating Pump1
Boiler Furnace2Burners3
Water Walls4
Super heater No.15
Super heater No.26
Super heater No.37
Super heater No.38
Steam Supply To Hp Turbine9
Re heater No.110
Exhaust Steam From Hp Turbine11
Economizer12
Exhaust Outlet13
Air Inlet14
High Pressure (Hp) Turbine15
Intermediate Pressure (IP) Turbine16
Low Pressure (LP) Turbines17Generator18
Lead Box19
23kv To Transformer20
Condensate/Boiler Feed water To Boiler22
Water Box (Sea Water)23
Steam Supply To IP Turbine24
Gas Recirculation25
Condenser26
Condenser Hot Well27
Table 2-1
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 37
Fig. 2-5 Main Circulating Flows in Greater Detail
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 39
COMPRESSOR
The Compressor consists of rotating blades and stationary vanes. Air is compressed as
it flows axially along the shaft. This allows greater efficiency and higher pressure
ratios by multi-stage construction. A stage of compression consists of one row ofrotating blades followed by a row of stationary vanes. Axial flow compressor, as
shown in Fig. 2-7, is the most common type of compressor used in gas turbine power
plant engines.
The Function of axial flow compressor is to furnish high pressure air to the
combustion chamber for production of hot gases necessary to operate the turbine.
Only a portion of compressor air is used for combustion. The compressor also serves
as a source of cooling air for turbine nozzles, turbine wheels, transition pieces,
bearings and other portions of hot gas path. The air, which continuously discharges
from the compressor, will occupy a smaller volume at the compressor discharge than
at the outlet. Due to heating during compression, the air temperature will increase
several hundred degrees Fahrenheit.
Fig. 2-7 Axial Compressor
COMBUSTOR
Referring to Fig 2-8 for GE type and 2-9 for ABB type, the combustor mixes the
compressed air with fuel and burns the mixture to provide a hot expanding gas. Each
combustion chamber assembly is made up of combustion can (liner), a fuel nozzle,
and a transition piece.
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Fig 2-8 Combustor (GE Type)
Fig 2-9 Combustor (ABB Type)
GAS TURBINE
The three-stage turbine section is the area in which energy in the form of high
temperature pressurizes.
Turbine Rotor: The turbine rotor assembly, shown in Fig. 2-10, consists of the
forward and aft turbine wheel shafts and the first, second and third stage turbine wheel
assemblies with spacers and turbine buckets. Concentricity control is achieved with
mating rabbets on the turbine wheels, wheel shafts, and spacers. The wheels are held
together with through bolts mating up with bolting flanges on the wheel shafts and
spacers. Selective positioning of rotor members is performed to minimize balancecorrections.
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Fig. 2-10 Turbine Rotor Assembly
Turbine Stator: The turbine casing and the exhaust frame constitute the major
portion of the turbine stator structure. The turbine nozzles, shrouds, and turbine
exhaust diffuser are internally supported by these components.
2.3 MAJOR COMPONENTS OF COMBINED CYCLE
Fig. 2-11 illustrates the major components of combined cycle.
1.
Condenser
2. Steam turbine
3. Gas turbine
4. HRSG (Fig. 2-12 and Fig. 2-13)
5. Pump
6. Electric generator
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INFORMATION SHEET
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2.4 INSTRUMENTATION&MONITORING SYSTEMS
Instruments in the power plants are devices that measure mechanical variables such as
flow, temperature, level or pressure. These variables are used by transmitters to
change into electronic signals for the measuring instruments displaying the units orindicating the reading on pointer scales (see Fig. 2-14, 2-15, 2-16 and 2-17).
Instruments include various related devices, which can be as simple as valves and
transmitters, and as complex as analyzers. Instruments often comprise control systems
of various processes. The process control is one of the main branches of applied
instrumentation.
Fig. 2-14 Pressure Instrumentation Equipment
Fig. 2-15 Non-contact Ultrasonic Sensor
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Fig. 2-16 Level Transmitters
Fig. 2-17 Temperature Instrumentation Equipments
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PART II MAIN ELECTRICAL COMPONENTS
2.5 POWER SYSTEM COMPONENTS
The power system is divided into three parts; power plant, transmission system anddistribution system, as shown in Fig. 2-18.
Fig. 2-18 Single Line Diagram for Power System Network
2.6 GENERATION COMPONENTS
GENERATOR
The generator is a device that converts mechanical energy into electrical energy. It is
based on the principle of "electromagnetic induction" that if an electric conductor, like
a copper wire, is moved through a magnetic field, an electric current will flow (be
induced) in the conductor, as shown in Fig. 2-19. So the mechanical energy of the
moving wire is converted into the electric energy of the current collected from the
generator winding.
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Fig. 2-19 Electrical Generator in steam power plant
POWER TRANSFORMER
The power transformer is used to transfer electrical energy from one circuit to another
through inductively coupled conductors (coils). It steps up the voltage in order to
decrease current and power losses when transferring the power to long distance
locations. AC current in the primary winding creates a varying magnetic flux in the
transformer's core, and thus a varying magnetic field through the secondary winding,
That induces an AC voltage in the secondary winding. If a load is connected to the
secondary, an electric current will flow in the secondary winding and electrical energy
will be transferred from the primary circuit through the transformer to the load (see
Fig. 2-20)..
Fig. 2-20 Power Transformer
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DISCONNECTORS AND EARTH SWITCHES
Disconnectors and earthing switches are safety devices used to open or close a circuit
when there is no current flowing through them (Fig. 2-21). They are used to isolate a
part of a circuit, a machine, a part of an overhead line or an underground line so thatmaintenance can be safely conducted.
Disconnect switches are used to complete a connection to or isolate the following:
1- Two energized transmission or distribution lines.
2- Transmission or distribution lines from substation equipment.
3- Substation equipment.
4- A distribution feeder circuit and a branch circuit.
Disconnect switches are frequently used to isolate a line or an apparatus, such as a
transformer. To complete maintenance work in most circumstances, it is necessary to
test the equipment for high voltage and, if proved de-energized to ground it before the
maintenance work is performed.
Fig. 2-21 Disconnected Switches
2.7 TRANSMISSION COMPONENTS
TRANSMISSION LINES
A transmission line provides the means to transfer high voltage electric power fromone place to another carrying on towers by suspension insulators. Transmission lines
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are used in the form of isolated strip lines made basically from copper with some
alloys like aluminum, as shown in Fig. 2-22.
Fig. 2-22 Overhead Transmission Line
BUS BAR
A bus bar is a device that connects high voltage feeder to multiple feeders in order to
distribute power in many directions, as shown in Fig. 2-23 and Fig.2-24. It can be
found indoor or outdoor. The bus bar structure is made of copper and depends on the power capacity.
Fig. 2-23 69KV High Voltage Bus Bar Substation
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Fig. 2-24 220KV GIS High Voltage Bus Bar Substation
UNDERGROUND CABLES
The underground cable provides the means to transfer high voltage electric power
from one place to another through the network but transmission burying under earth
surface. It is made of strong bundle of copper conductors surrounded by a thick layer
of a suitable insulating jacket impregnated with supporting material (Fig. 2-25).
Fig. 2-25 High Voltage Underground Cables
DC SYSTEMS
DC systems provide DC power that can be stored in rechargeable batteries to feed
protection & control equipment, alarms, communications, fire fighting, data systems
and instrumentations. DC systems include Station Battery Chargers that convert AC
power into DC power to be stored in battery banks, as shown in Fig 2-26 and 2-27.
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Fig. 2-26 Station Battery Chargers
Fig. 2-27 Station Battery Bank
2.8 POWER SYSTEM PROTECTION
Power system protection is used to protect power system equipment against faults and
abnormal conditions through the isolation of faulted parts from the rest of the
electrical network (Fig. 2-28). 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. Power system protection
also responds to malfunctions in controls, alarms and annunciations keeping a log of
the emergency events. Protection equipment always need DC source to operate all
functions.
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Fig. 2-28 Power System Protection
Protection system consists of three main function blocks, which are:
- Sensing elements block (current transformer & voltage transformer).
- Decision elements block (protective relays).
- Action elements block (circuit breaker).
CURRENT & VOLTAGE TRANSFORMERS
Current and voltage transformers act as the sensing elements block, which transduce
the current and voltage signals for the protective relays to continue the protection
process, as shown in Fig. 2-29 and 2-30.
Fig. 2-29 Different Types of Current Transformer
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Fig. 2-30 Different Types of Voltage Transformer
PROTECTIVE RELAYS
Protective relays act as the decision elements block, verifying and analyzing the
current and voltage signals to decide if there is a fault or not (see Fig. 2-31). Under the
fault condition, a trip signal activates the circuit breaker.
Fig. 2-31 Different Types of Protective Relays
CIRCUIT BREAKER
A circuit breaker is an electrical switch to be operated either manually or automatically.
It is designed to protect power system from damage caused by overload or short
circuit. Its basic function is to receive fault signal from protection and interrupting
power flow, immediately. Unlike a fuse, a circuit breaker can be reset to resume
normal operation. Circuit breakers have many types according to their arc quenchingcapabilities in arc chambers.
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from the power system to control center to help in making suitable decisions and fast
actions in emergency cases. It may use wireless, telephone, power line carrier (PLC),
microwave or fiber optics as medium of communication (Fig. 2-34 and Fig. 2-35).
Fig. 2-34 Fiber Optics Communication Panel
Fig. 2-35 Communication System
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2.9 POWER DISPATCHING
OBJECTIVES OF POWER DISPATCHING
1.
To ensure that the system is operated in a safe and efficient manner. This involvesthe current operation of switching programs and accurate logging of all operations.
2. To take all reasonable precautions to ensure continuity of supply and maintain the
stability of the system.
3. To ensure compliance with SEC safety rules at all times.
In order to achieve these objectives the Power Dispatching (control center) must:
a. Keep an overall view of the Network and ensure accurate updating of the system
operation diagram as operations are carried out.
b. Authorize all switching, earthing and clearances.
c. Ensure that accurate records are kept of 'times of issues of instructions for
switching' and the 'time of completion of operations by Network Operators'.
d. Coordinate switching between the different areas.
2.10 DISTRIBUTION SYSTEM
The distribution system is fed through grid stations. They are of a large capacity and
supply power to a large area through many primary feeders. Each primary feeder is
supplying several distribution substations Fig. 2-36.
PRIMARY DISTRIBUTION
The primary distribution voltage is obtained from a step-down transformer existing
inside the grid station. The primary distribution voltage is then distributed to different
customers. The grid station could be indoor (a grid station connected to loads at 13.8
kV) or outdoor. Primary distribution lines connect power to the grid station anddistribution substation either overhead or underground.
DISTRIBUTION SUBSTATION
Distribution Substations are those substations, which are located nearest to the load.
The outgoing feeder from the Grid Station feeds the distribution substation at 13.8 kV
or 34.5 kV from Grid Station and reduces to a level suitable for distribution at 230V,
and/or 127 V.
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Fig. 2-36 Distribution System Diagram
TYPES OF DISTRIBUTION SUBSTATIONS
There are many types of substations used in primary distribution such as, UnitSubstation, Package substation, Room substation, Pole mounted transformer, Platform
mounted transformer and Pad mounted transformer.
POLE MOUNTED TRANSFORMERS-PMT (OUTDOOR)
Fig. 2-37 shows Pole mounted transformer. In this type, the high tension is supplied to
the transformers by overhead lines.
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Fig. 2-37 Pole Mounted Transformer
PLATFORM MOUNTED TRANSFORMER
Fig. 2-38 shows platform mounted transformer. The high tension is supplied to the
transformer either by overhead lines or by underground cables from Ring Main Unit
(RMU).
Fig. 2-38 Platform Mounted Transformer
UNIT SUBSTATION
Unit substations, as shown in Fig. 2-39, consist of a 13.8 kV/LV distribution
transformer with an integral LV distribution panel. Unit substations are used to supplyLV network in residential and commercial areas. The advantage of unit substations is
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its compact size, which makes it easier to obtain sites for installation (2X 5.5 M) and
easier to find a point to provide the LV network with short LV feeders.
Fig. 2-39 Unit Substation
PACKAGE SUBSTATION
The ring main unit (RMU), transformer, and secondary voltage distribution cabinet
form one unit, as shown in Fig. 2-40.
Fig. 2-40 Package Substation
ROOM TYPE SUBSTATION
The main equipments installed in a room-type substation are the transformer, ring
main unit, LV panel, and HV/LV cables. The transformer at room type is a ground-
mounted (500/1000/1500 kVA). RMU is ground-mounted with two 400 amp ring
switches. LV distribution panel at 1600 A feeds eight outgoing feeders, 400 amperes
each, as shown in Fig. 2-41.
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Fig. 2-41 Room Substation
OIL SWITCH
An oil switch is a high-voltage switch whose contacts are opened and closed in oil.The switch is actually immersed in an oil bath contained in a steel tank. The reason for
placing high-voltage switches in oil is that the oil will break the circuit when the
switch is opened. With high voltages, a separation of the switch
contacts does not always break the current flow because an electric arc forms between
the contacts. If the contacts are opened in oil, it will quench the arc. Furthermore, if an
arc should form in the oil, it will evaporate part of the oil because of the high
temperature and will partially fill the interrupters surrounding the switch contacts with
vaporized oil. This vapor develops a pressure in the interrupters which assists inquenching or breaking the arc by elongating the arc (Fig. 2-42).
Fig. 2-42 Oil Switch
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SF6 RING MAIN UNIT (RMU)
The Ring Main Unit is a standard piece of switchgear in distribution systems
comprising of switches for switching power cable rings and of switches in series with
fuses for the protection of distribution transformers. Sulfur hexafluoride SF6 ring mainunit is fully insulated in SF6 gas that is used as insulating and switching medium, as
shown in Fig. 2-43.
Fig. 2-43 SF6 Ring Main Unit
It is an inert, heavy gas having good dielectric and arc extinguishing properties. The
dielectric strength of the gas increases with pressure and is more than that of electric
oil. The gas insulated units are insensitive to environmental influences, e.g. humidity,
dirt, dust etc. It has a compact self-supporting metal-clad structure and it is
maintenance free. This gas is now being very widely used in electrical equipment such
as high voltage circuit-breakers.
DISTRIBUTION TRANSFORMERS
The distribution transformer is used to convert electrical energy of higher voltage
(usually 13.8 KV) to a lower voltage (380/220/127V) with an identical frequency
before and after the transformation. The application of the product is mainly within
suburban areas, public supply authorities and industrial customers. With a given
secondary voltage, the distribution transformer is usually the last in the chain of
electrical energy supply to households and industrial enterprises, as shown in Fig. 2-44.
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Fig. 2-44 Transformer core and windings
LV PANEL
LV panel 1600 A is one of the main components of SEC distribution network. LV
panel receives incoming cables from the transformer. The outgoing secondary from
LV panel can feed 7 minipillars for the transformer capacity 500kVA and 12
minipillars for the transformer capacity 1000kVA (Fig. 2-45).
Fig. 2-45 LV Panel
MINIPILLARS
The Minipillar is one of the major components of SEC LV Distribution networks.
Minipillars are installed outdoors to receive incoming cables from the LV panels. The
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minipillars are capable of accepting up to two 4 × 300 mm2 Aluminum cables and
feed five customers by 4 × 70 mm2 Aluminum service cables, as shown in Fig. 2-46.
Fig. 2-46 Minipillar
METER CLASSIFICATIONS
The electrical power is the rate at which electrical energy is used and its unit of
measurement is Watt (W), while the unit of measuring electrical energy is Watt-Hour
(WH). The instrument used to measure the electrical energy is Watt-Hour meter,
which measures the total electrical energy during specific time as kilo-Watt-Hour
(kWH).
METER TYPES
WHOLE CURRENT (WC) METERS
Used for low voltage customer, which has load not exceeding 150 ampere.
CURRENT TRANSFORMER (CT) METERS
Used for customer, with loads exceeding 150 ampere.
CURRENT AND VOLTAGE TRANSFORMERS (CT&PT) METERS
Used for customer with loads from medium voltage 13.8 kV and above.
WATTHOUR METERS
The WH meter is an instrument that is used to measure electrical energy. The (kWH)meter is an instrument that is used to measure electric energy, which is sold by SEC,
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as shown in Fig. 2-47. Its function is to provide an accurate record of the electric
energy. kWH meters measure the amount of electric energy passing through various
parts of the generating, transmission and distribution systems.
Fig. 2-47 Low Voltage Watt-hour Meter
DISTRIBUTION OVERHEAD LINES
Overhead lines (OH) can be made of copper or aluminum conductors strung on steel
poles using insulators. Steel poles are used for carrying conductors between power
sending and receiving ends in distribution networks. Steel poles are widely used for
OH distribution lines (LV, 13.8kV and 34.5kV,69kV), In some cases, Steel poles are
carrying some of the distribution line equipment, e.g., Transformers, Fuse Cutouts,
Voltage Regulators, etc..
UNDERGROUND CABLES (LINES)
The cables are normally buried directly in ground, in trenches. Sometimes, the cable is
placed in ducts as in cases of road crossings. Cables used for primary distribution have
three cores with aluminum or copper conductors. They are mostly insulated either by
XLPE (Cross Linked Polyethylene) or by PILC (Paper Insulated Lead Covered), as inold cables. In addition, underground cables are protectively armored or sheathed to
protect against moisture, gases and acids that exist in the ground and also to protect
against any mechanical damage.
Power cables are used to conduct electrical power from one point to another in the
electrical circuit. Power cables connect the various components of electrical power
systems such as transformers, circuit breakers, switchgear, etc, to each other as
specified in the system design plan.
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SUMMARY
- The steam turbine generator being rotating equipment generally has a heavy, large
diameter shaft.
-
The Function of axial flow compressor in gas turbine is to furnish high pressure airto the combustion chamber for production of hot gases necessary to operate the
turbine.
- Instruments in the power plants are devices that measure mechanical variables
such as flow, temperature, level or pressure.
- The power system is divided into three parts: power plant, transmission system and
distribution system.
- The Generator is a device that converts mechanical energy into electrical energy.
- The Power transformer is used to step up the voltage in order to decrease the
current and power losses when transferring the power to long distance locations.
- The Underground cable provides the means to transfer high voltage electric power
from one place to another through the network under earth surface.
-
The power system protection is used to protect power system equipment against
faults and abnormal conditions through the isolation of faulted parts from the rest
of the electrical network.
- The circuit breaker is designed to protect power system from damage that may
have been caused by overload or short circuit.
-
The distribution system is fed through grid stations.
- Steel poles are widely used for OH distribution lines (LV, 13.8kV and 34.5kV,
69kV).
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65
LESSON 3
INDUSTRIAL
TRAINING PROGRAM(ITP) CRAFTS
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LESSON 3
INDUSTRIAL TRAINING PROGRAM (ITP) CRAFTS
OVERVIEW
This lesson familiarizes the participants with different crafts of industrial training
program (ITP) in generation, transmission and distribution sectors.
OBJECTIVES
Upon completion of this lesson, the participants should be able to:
Identify and familiarize with:
I-ELECTRICAL SPECIALIZATIONS
- Power Plants Electrical Maintenance (Power Plant Electrician)
-
Electrical Network Operation (Network Operator)
- Electrical Distribution Network Maintenance (Distribution Electrician)
- Overhead Line Maintenance (Lineman)
- Electric Power Cables (Cableman)
- Substation Electrical Maintenance (Power Service Electrician):
-
Power System Protection And Control (Relayman)
- Instrumentation And Control (Instrumentation Technician)
- SCADA
- Telecommunications
II-MECHANICAL SPECIALIZATIONS
- Power Plant Mechanical Maintenance
-
Welding And Machining- Water Treatment Plant Operation
- Diesel Power Plant Operation
- Gas Power Plant Operation
- Steam Power Plant Operation
- Industrial Drafting
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I-ELECTRICAL SPECIALIZATIONS
POWER PLANTS ELECTRICAL MAINTENANCE (PPE)
This program aims to prepare and qualify the trainee to perform maintenance and
repair for the electrical power plant equipment, such as motors, MV & LV
switchgears, electrical systems, fire fighting systems and other auxiliary systems.it
also aims to qualify him to check generators and exciter circuits and to be able to
verify electrical installation works of the power plant.
MAIN DUTIES
Performing routine electrical maintenance of all electrical equipment in power
plant.
Maintaining test and measuring equipment.
Carrying out maintenance activities related to major overhaul on Generators
Battery discharge testing.
Generator Bearing Insulation testing & shaft voltage/current detection &
monitoring.
Following the procedure of electrical equipment during Minor & Major
Inspections. Following the plant lighting system and low voltage distribution panel.
Following the workshop equipment.
Following the overhead gantry cranes.
Following the main generator and exciter.
ELECTRICAL NETWORK OPERATION (NWO)
This program aims to prepare and qualify the trainee to perform pre-commissioningtests in the transmission and distribution networks tripping and be able to isolate the
electrical equipment to let maintenance technicians perform their duties, pertaining to
isolating the faulty parts, equipment schematic reading, hold tags, work permits and
clearances, switching and grounding procedures and re-energizing the power,
checking the equipment and monitoring loads, in a completely safe atmosphere.
MAIN DUTIES FOR DISTRIBUTION AND TRANSMISSION (NWO)
Operation of transmission/ distribution network equipment.
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Operation of overhead transmission/ distribution lines.
Operation of underground transmission equipment / lines.
Inspection of transmission substations.
De-energizing / Re-energizing of transmission equipment.
Reading and recording of indicating meters and gauges. Management of forced distribution outages.
Recording and resetting of relay targets.
Issue and cancellation of work permit.
Site inspection and work supervision
Operation of underground distribution equipment / lines
Inspection of distribution substations / grid stations
De-energizing / Re-energizing of distribution equipment
Recommendation for corrective action / system improvement
Preparation of weekly shutdown schedule / work program (s)
Coordination with other unit for rectification / repair
ELECTRICAL DISTRIBUTION NETWORK MAINTENANCE
(EDM)
This program aims to prepare and qualify the trainee to install and maintain electrical
energy counters, to do the monthly periodical maintenance, repairing, installation and
inspection to the transformers, switchgears and the main & auxiliary distribution
boards, LV circuits switching, and to troubleshoot low voltage circuits, joints and
terminals of MV & LV cables.
MAIN DUTIES
Operation of LV equipment.
Installing / commission requested customer service.
Maintain requested customer service. Maintenance of LV and MV system.
Testing MV/LV cable and equipment.
Maintains documents and records.
Load readings.
Usage of test / measuring equipment.
Inspecting / monitor contractor work.
Troubleshooting customer complaints.
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 71
OVERHEAD LINE MAINTENANCE (OHL)
This program is aimed to supply the trainee with knowledge and hand skills in the
installations of transmission line network equipment for HV, MV & LV, arranging
with the associated network, also doing the routine maintenance procedure, checkingall T.Ls equipment and towers, also training to climb the wooden and T.L towers,
using hydraulic and mechanical equipment, and using drilling equipment in the
installation and maintenance of TLs, also washing and insulators T.L equipment for
transmission and distribution networks.
MAIN DUTIES
Maintenance and repair of power lines
Power line insulating and substation washing
Inspection of Power Transmission lines
Using of test equipment
Coordinating with Power Control Center (PCC) Network operator
Preparing lists of materials and tools required for jobs
Maintaining documents and records according to standard procedures
Reading diagrams and blue prints
Complying with safety procedures and requirements
ELECTRIC POWER CABLES (EPC)
This program aims to supply the trainee with knowledge and hand skills in the
working of inspection and maintenance of cables for MV & LV, doing joints for the
HV cables from 15kV up to 69 kV in different cases like creating new networks and
joining with the associated networks, and doing cable testing, grounding and the
routine maintenance procedure for all types of cables.
MAIN DUTIES
Installation and splicing of cables
Testing and Inspection of cables network
Maintenance and Repair of cable network
Using of test equipment
Coordinating with Power Control Center (PCC) Network operator
Preparing lists of materials and tools required for jobs Maintaining documents and records according to standard procedures
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INFORMATION SHEET
72 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
SUBSTATION ELECTRICAL MAINTENANCE (SSM)
This program aims to prepare and qualify the trainee to maintaine the substation and
its equipment such as power transformers, switchgears, disconnected switches, bus
bars, insulators, motor control, power supply and other equipment. It also aims toqualify the trainee to remove faults and do the necessary in this regard.
MAIN DUTIES
Inspection, functional checks, maintenance, testing and commissioning of
transmission substation equipment.
Troubleshooting, repairing and restoring substation equipment to service.
Interface activities with Power Control Center (PCC).
Replacing/changing substation equipment.
Maintenance and use of test equipment.
Maintenance of substation auxiliary and station service equipment.
Preparing lists of spare parts, materials and tools required.
Driving and Operating Heavy Equipment.
Commission newly constructed substations / substation additions.
Supervising/training subordinate staff.
Maintaining documents and records according to standard procedures.
POWER SYSTEM PROTECTION AND CONTROL (PSP)
This program is designed to qualify the trainee to be able to install, maintain and test
the protection devices (relays) and inspect, connect and test the current and voltage
transformers, read electrical drawings and use them to indicate and remove the fault
from the control and operation circuits for all HV & MV equipment, measure
instrument calibration & recorders and do all tests for electrical equipment.
MAIN DUTIES
Maintaining all types of relays.
Maintaining pilot relaying equipment.
Maintaining automatic voltage regulator relays.
Maintaining transducers.
Maintaining Watt-Hour and VAR-Hour meters.
Maintaining indicating meters. Maintaining fault recorders.
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 73
Maintaining annunciator systems.
Maintaining instrument transformers.
Repairing battery chargers.
INSTRUMENTATION AND CONTROL (INC)
This program is designed to qualify the trainee to be able to inspect and troubleshoot
and calibrate control and protection equipment which is used in power plants to
monitor the liquid levels, flow rate, temperature, different pressures in the tubes and
tanks, vibration equipment, calibration for control valves and operation and calibration
for measuring instruments & recorders.
MAIN DUTIES
Performing preventive maintenance checks, test, calibrate, troubleshoot, and make
critical adjustments to all field instruments.
Performing preventive maintenance, troubleshooting, turbine vibration and turbine
speed measuring instruments.
Performing commissioning tests on all types of instrumentation and control
schemes.
Performing wiring termination for different instruments at hazardous and non
hazardous locations.
Performing soldering and de-soldering for electronic components and integrated
circuits.
SCADA (SCD)
This program aims to familiarize the trainee with the electronic components such as
semiconductors, logic and digital circuits, printed circuit boards, soldering for
electronic components, and with the basic technical concepts used in SCADA
systems. it also familiarizes the trinee with in-depth study of microprocessor
applications.
MAIN DUTIES
Operation and Maintenance of Instruments.
Operation and Maintenance of Remote Terminal Units (RTUs).
Operation and Maintenance of Auxiliary Equipment. Preventive Maintenance- Routine Checks/Inspections of SCADA Systems.
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INFORMATION SHEET
74 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
(Installing/Modifying/Replacing required SCADA Equipment.
Maintenance of SCADA Services for in-house.
Operation and Maintenance of Master Stations.
Software Configuration of SCADA RTUs and Communication Protocols
Supervising/Training Subordinate Staff.
TELECOMMUNICATIONS (TCM)
This program aims to familiarize the trainee with the electronic components such as
semiconductors, logic and digital circuits, printed circuit boards, soldering for
electronic components, familiarization with the basic technical concepts used in
telecommunications, how to check them, troubleshoot and repair them. It also
familiarizes the trinee with in-depth study of microprocessor applications.
MAIN DUTIES
Maintenance of Test Equipment.
Functional checks, routine inspection and maintenance of Communications
Switching Networks.
Monitoring and commissioning of Communication Switching Networks.
Functional checks, routine inspection and maintenace of Communications Carrier
Networks.
Monitoring and commissioning of Communication Carrier Networks.
Functional checks, routine inspection and maintenance of Communications Carrier
Cable Links.
II-MECHANICAL SPECIALIZATIONS
POWER PLANT MECHANICAL MAINTENANCE (PPM)
This program is designed to qualify the trainee to be able to perform routine and
preventive maintenance, disassembly, repair, replacement, re-assembly and
reinstallation, of various types of mechanical equipment including all rotating
equipment and auxiliary equipment in a power plant.
MAIN DUTIES
Maintaining Manually Operated Valves. Maintaining Machine Alignment.
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INFORMATION SHEET
76 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
DIESEL POWER PLANT OPERATION (DPO)
This program aims to prepare and qualify the trainee to perform start-up/shutdown and
normal running of diesel plants, operate mechanical and electrical components used ina Diesel power plant, monitor operating conditions (lube oil system, water system, air-
cooling system), make adjustments either at the control board or within the plant to
ensure safe operations and trip and isolate the equipment to let maintenance
technicians do their duties safely by isolating the faulty parts.
GAS POWER PLANT OPERATION (GPO)
This program is aimed to prepare and qualify the trainee to perform start-up/shutdown
and normal running of gas turbine plants, operate mechanical and electrical
components used in a gas turbine power plant, monitor operating conditions, make
adjustments either at the Display Panel or within the plant to ensure safe operations
and trip and isolate the equipment to let maintenance technicians perform their duties
safely by isolating the faulty parts.
STEAM POWER PLANT OPERATION (SPO)
This program is aimed to prepare and qualify the trainee to perform start-up/shutdown
and normal running of steam power plants, acquire sufficient operational knowledge
about auxiliary systems, mechanical and electrical main components used in a steam
power plant, monitor operating conditions, make adjustments either at the Display
Panel or within the plant to ensure safe operations, trip and isolate the equipment to let
maintenance technicians perform their duties safely by isolating the faulty parts.
MAIN DUTIES (GPO, SPO and DPO)
Responsible for monitoring and controlling power plant generating units & its
associated auxiliary equipment and operating conditions round the clock to ensure
continuous, safe and cost effective power generation.
Start-up or shut-down of assigned balance of plant (BOP) equipment according to
approved operating procedure and general instructions.
Shift duties with responsibility for physically inspecting the operating status,
mechanical and electrical conditions of assigned balance of plant (BOP) equipment
Physical inspections of the assigned balance of plant (BOP) equipment to ensurethat the plant is functioning at optimum operating performance.
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INFORMATION SHEET
TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook 77
Checking on the mechanical and electrical conditions of equipment.
Operate all turbine systems including air, cooling water, lube oil, fuel gas/ lube oil,
AC and DC power panels and batteries.
Taking appropriate corrective action when necessary and report all conditions to
the Control Room Operator / Supervisor. Operating the equipment in accordance with the manufacture's specifications.
Responding to emergency or upset conditions taking necessary shut down or
adjustment action to restore stable operating conditions as directed.
Supporting operator to troubleshoots and correct operations problems in the
assigned equipment.
INDUSTRIAL DRAFTING (DRF)
This program aims to supply the trainees with basic knowledge and skills on free hand
lettering and sketching. In addition, they will be able to understand the standard
symbols, drafting basics and use computer aided drafting soft ware.
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INFORMATION SHEET
78 TSC-GC07 Electrical Power Systems for Non-Technical Employees,Textbook
SUMMARY
WHERE:
G : Generation SectorPT : Power Transmission Sector
MDNO : Main Distribution Network Operations Department
DS : Distribution Sector
GS : General Services
Department Served
Training ProgramGPTMDNODSGS
1-Power Plants Electrical MaintenanceX-------- 2-Electrical Network Operation--XX----
3-Electrical Distribution Network Maintenance------X--
4-Overhead Line Maintenance--XXX--
5-Electric Power CablesXXX--
6-Substation Electrical MaintenanceXXX----
7-Power System Protection and ControlXXX----
8-Instrumentation and ControlX--------
9-SCADA--X------
10-Telecommunications--------X
11-Power Plant Mechanical MaintenanceX--------
12-Welding and MachiningX--------
13-Water Treatment Plant OperationX--------
14-Diesel Power Plant OperationX--------
15-Gas Power Plant OperationX--------
16-Steam Power Plant OperationX--------
17-Industrial DraftingXXXXX
18-AC & Refrigeration MaintenanceXXXXX
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BOOK EDITION
ELECTRICAL POWER SYSTEMS
FOR NON-TECHNICAL EMPLOYEESTextbook/Workbook
SPECIAL SHORT COURSE (TSC-GC07)
March 2010
Curriculum Development Division (CDD)Training Services Department (TSD)
Curriculum Developer : ELECTRICAL&MECHANICAL GROUPS
Technical Reviewer (Electrical) : FAROUK BESESO / MOHAMMED K. ABU-ROB
Technical Reviewer (Mechanical) : RIYAD AL-DROBI