KEEE 4253 POWER SYSTEM ANALYSIS

Course Overview

C O iCourse Overview

Lecturer : Dr. Hazlie MokhlisRoom : Block E Makmal Sistem KuasaRoom : Block E, Makmal Sistem KuasaContact : 03-79675238, hazli@um.edu.my

1. Learning Outcomes:1. Learning Outcomes:

1) Calculate load flow problems based on iterativemethods.

2) Estimate the effects of asymmetrical faults on the2) Estimate the effects of asymmetrical faults on thepower system.

3) Select the best protection scheme for a powerp psystem.

4) Assess the stability of a power system.

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2. Assessment Methods:2. Assessment Methods:

Continuous assessment : 40 %Mid-term test : 20%Mid-term test : 20%Assignment (Group, individual)&Quiz : 15%Participation in class : 5%

Final Examination : 60%

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3. Method of Delivery:3. Method of Delivery:

Lecture Problem based Learning tutorialsLecture, Problem based Learning, tutorials

Using ‘e learning’ http://spectrum um edu my/Using e-learning’ http://spectrum.um.edu.my/

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4. Main Reference:4. Main Reference:

1) John J. Grainger, William D. Stevenson, “PowerSystem Analysis”, McGRAW-HILL International Edition.

2) Hadi Saadat, “Power System Analysis”, McGRAW-HILL International Edition.

3) Other power system books3) Other power system books.4) Other sources from various Websites

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KEEE 4253 POWER SYSTEM ANALYSIS

INTRODUCTION TO POWER SYSTEM ANALYSISSYSTEM ANALYSIS

Importance of Electrical EEnergy

Convenient formConvenient formEasy controlGreater flexibilityCheapnessCleanlinessHigh transmission efficiencyg y

What Is a Power System?A system dedicated to the business of electricA system dedicated to the business of electric power:

Generation (Production)Transmission (Transportation)Distribution (Retailing)

A system that provides a vital service to the societyA system that provides a vital service to the society and should be operated with the goal of achieving:

Highest reliability standardsMi i i t l i tMinimum environmental impactsLowest operation cost

El t i P S tElectric Power Systems

Generation 11 to 25 kVGeneration – 11 to 25 kVTransmission – 66 to 400 kV

S b i i 33 kV 132 kVSubtransmission – 33 kV to 132 kVDistribution

Primary feeders – 11 kVSecondary feeders – 230 V/415 V

Power System ComponentsPower System Components

ConsumptionTransmission DistributionGeneration

Po erPower GenerationGeneration

P G tiPower GenerationTakes place in geographically dispersed power plantsTakes place in geographically dispersed power plantsPower plants normally house multiple generating unitsGenerating units can operate based on different:

Energy SourcesEnergy Conversion processes

EnergyEnergy Energy ElectricEnergyConversion 1

EnergySource

EnergyConversion n

A Generation Unit

Electric Power

A Generation Unit

S f ESources of EnergyHydrocarbones (oil coal natural gas etc )Hydrocarbones (oil, coal, natural gas, etc.)WaterN lNuclearWindSolarTidalChemical

Comparisons of Energy SourcesSources

Particular Water Fuels Nuclear

Initial cost High Low Highest

Running cost Less High LeastRunning cost Less High Least

Reserves Permanent Exhaustible Inexhaustible

Cleanliness Cleanest Dirtiest Clean

Simplicity Simplest Complex MostSimplicity Simplest Complex Most complex

Reliability Most Less More reliabley

G ti St tiGenerating Stations

St t tiSteam power stationsHydro-electric power stationsDiesel power stationsNuclear power stations

PPower TransmissionTransmission

P T i iPower TransmissionTransmission networks are needed to :Transmission networks are needed to :

Connect generating plants to consumption pointsCreate large power pools for increased reliabilityg p p y

High voltage AC transmission offers:Higher transmission capacity / KmLower line-voltage drop / KmLower transmission losses / MW transferReduced right-of-way requirement / MW transferLower capital and operating costs / MW transfer

Power Transmission E i tEquipments

TransformersStep-up transformersV lt R l tVoltage RegulatorsPhase ShiftersStep-down Transformers

T i i Li & C blTransmission Lines & CablesCircuit Breakers & DisconnectsShunt & Series Reactors & CapacitorsStatic VAR CompensatorsFACTS DevicesEtc.

Power Di t ib tiDistribution

P S t Di t ib tiPower System DistributionsReceives electrical energy from the HV/MV levels atReceives electrical energy from the HV/MV levels at bulk power delivery pointsSupplies energy to customers:

At standard voltage levelsAt standard voltage levelsSingle phase and/or three-phase

Is made up of the following main equipment:Distribution transformers (DXF)Feeder sections (including underground cables)Switches, fuses, reclosuresAutomatic load transfersEtc.

P S t Di t ib tiPower System Distributions

HV / MVNetwork Industrial

C

ResidentialCustomers

Commercial& Municipal

LargeI d i l

Bulk33/11

Customers Customers& MunicipalCustomers

IndustrialCustomers

PowerPoint

33/11DXF

11/0.4DXF

400/230DXF

33KV 11 KV 400 V 230V

Role of Power System E iEngineers

Planning how much electricity to generate

h h d i h t f lwhere, when and using what fuelFor planning, improvement and expansion of a power system needs:power system, needs:

Load flow studiesShort circuit studiesStability studies Economic load dispatchLoad frequency controlLoad frequency control

Why we need to study power system ?Why we need to study power system ?

Power System are among the most important components of infrastructure of a modern society.We depend on a very high level of electrical reliability. Power System are among the most complex man-made engineering systemsengineering systems. In Power System study various field of science are involve as well as economics.

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• In engineering and science, the important fields include:

Energy conversionEnergy conversionMaterials and insulatorsNetworks and system theoryElectronicsControlCommunication systemComputerpMathematics and statistic.

In the filed of economics, problem dealing with:Risk analysis/finance/investment theoryRisk analysis/finance/investment theoryMicroeconomics (Market theories)

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The main goals in Power System operation and planning are high reliability and low cost with consideration of particular constraintsparticular constraints.Constrains are conditions on the variables of the system that must be met. The most important constrains are:o Power balance

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o Constraints on frequency, voltages and power flows:If the system frequency is donated by f(t), then generallythe following imposed:the following imposed:

Similarly for the bus voltages, HztfHz 5.50)(5.49 ≤≤

y g

And the power flows, where such constraints are ll i d f t bilit d th l t

putVpu 05.1)(95.0 ≤≤

generally imposed for stability and thermal stress reasons.

maxjkjk PP ≤ jkjk

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Introduction Power System AnalysisTo be able to meet the power balance constraint, the total demandmust be predicted. Loads usually follow nearly periodic daily cycles.As a result, the demand is generally approximately predictable.Since the demand is random and therefore not perfectly predictable,the scheduled generation must be able to track the load in time.Tracking errors lead to deviations of the system frequency form itsnominal value:

ObservationNotice that if Pg(t)>Pd(t) for long enough time, the frequency should t t d ifti t d i fi it O thstart drifting towards infinity. On the

other hand, if Pg(t)<Pd(t) for long enough time, the frequency will start drifting towards zero.

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drifting towards zero.

Electricity Supply Industry in Malaysia

An Overview

El t i UtilitiElectric UtilitiesTenaga Nasional Berhad (Tenaga) is theTenaga Nasional Berhad (Tenaga) is the dominant electric utility in Malaysia – 50% Sabah Electricity Sdn Bhd (SESB)Sabah Electricity Sdn.Bhd. (SESB)Sarawak Electricity Supply Corp. (SESCo)IPP - 40%IPP - 40%Dedicated power producer (Northern Utility Resources) and co-generation (captive)Resources) and co generation (captive) plants.

G ti d C tiGeneration and Consumption

TRANSMISSIONTRANSMISSION

Transmission network of TNB comprise ofTransmission network of TNB comprise of 132 kV, 275 kV and 500 kV system known as the National Gridthe National Grid. The system spans the whole of Peninsular Malaysia connecting power stations ownedMalaysia, connecting power stations owned by TNB and IPPs to the customers.

N ti l G idNational GridThe National Grid is interconnected to Thailand’sThe National Grid is interconnected to Thailand stransmission system operated by ElectricityGenerating Authority of Thailand (EGAT) in theN th i HVDC i t ti ithNorth via a HVDC interconnection with atransmission capacity of 300 MW and a 132 kVHVAC overhead line with maximum transmissioncapacity of 80 MW.In the South, the National Grid is connected toSingapore’s transmission system at Senoko via twoSingapore s transmission system at Senoko via two230 kV submarine cables with a firm transmissioncapacity of 200 MW.