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Electrical Engineeringfor Mechinacal EngineersElectrical Engineering department Umm Al-Qura University

Dr. Basim J. ZafarThis Course Applications of Electrical Engineeringin Different Systems..

Concepts and Basics of Electricity and Electronics..

Practical Engineering Applications..

Slide 22Course ContentHistory of Electricity

Basic Conceptselectrons, battery, DC&AC, frequency, closed loop, current, RMS

ComponentsR, C, L, fuses, breakers, relays, solenoids, diodes, transistors, ICsSlide 33Course ContentCircuit Analysisohms law, dividers, KCL, KVL, complex impedance, current source, power

Application Specific Circuits

Power Generation and DistributionDC machines, transformers, 3-phase systemsSlide 44Course ContentSensors & Actuatorsresistive, capacitive, inductivespecial sensorsdata acquisition

Slide 55Class FormatActive ClassTeams of 2 studentsWeekly Quiz (no makeup's)Weekly Activities In-Class Readings

Slide 66RulesQuizzesgrades 0 or 10be ON-TIMEabsence = -2no material on tablecalculator & pencil2 decimal points with proper unitscheating = BIG TROUBLE

Slide 77RulesActivitiesteam ID + members IDsnice fonts and presentationmembers loads must be equal

Teamworkany conflict should be stated from the beginningSlide 88GradesQuizzes / Class Activities 10%Mid Term Exams I15%Mid Term Exams II15%Final 40%Lab 20%

Slide 99Students IDsEE307 Sections

IDs in Teams:Team A: A1 A2.Team B: B1 B2.Team C: C1 C2.Team D: D1 D2.Team E: E1 E2.

Slide 10

10http://uqu.edu.sa/bjzafar

E-mailBJZafar@uqu.edu.sa

Class homepage11IntroductionSection 01History of ElectricityAncient Egyptian2750 BCshocks from electric fish

Slide 13

13History of ElectricityRomans1500 BCshocks can travel in metals

Thales600 BCNoticed static electricity from polishing amber with a piece of wool or fur.Arabs1400Identity of lightening

William Gilbert1600Coined the New Latin word electricus to refer to the property of attracting small objects after being rubbedSlide 1414History of ElectricityBenjamin Franklin1753lightening key experiment

Luigi Galvani1771-1791nerve cells passed signals to the muscles

Alessandro Volta1800invented thevoltaic pile consist of Zinc and silver.

Hans Christian rsted 1819demonstrates electromagnetism. Current flowing in a wire creates a magnetic field which deflects a compass needle.

Slide 1515History of ElectricityAndr-Marie Ampre 1820Figures out a way to measure the strength of a magnetic field in relation to an electric current, known as Amperes theorem.

Michael Faraday1831learned how to produce continuous voltage. |This was the first electric motor (generator).Georg Ohm 1827mathematically analyzed the electrical circuit (ohm's law)Tesla, Edison, Westinghouse, Siemens, 1900s Graham Bell and KelvinElectricity was turned from a scientific curiosity into an essential tool for modern life (Second Industrial Revolution)Slide 1616Machines MonitoringSlide 17

17Fully Programmed MachinesSlide 18

18EngravingSlide 19

19Control RoomsSlide 20

20AutomationSlide 21

21RobotsSlide 22

22AccuracySlide 23

23ExoMars MissionSlide 24

Life in other planets!

24ExoMars MissionSlide 25

landing of a large payload on Mars navigation and operation of a mobile scientific platform a novel drill to obtain subsurface samples sample processing and distribution system protection and cleanliness levels25ExoMars MissionSlide 26

26Printed Circuit Board (PCB)Slide 27

27Process Check, Home WorkAsk yourself..

What do I need to know about EE?

Slide 2828Basic ConceptsSection 02ElectronsAtoms and ElectronsSlide 30

30Is It Like This?!Slide 31

31ElectricityIf electrons were pushed, they produce a currentSlide 32

32BatterySource of pushing electronsElectrochemical reactionsLook for types of batteries in Wikipedia!! Home WorkSlide 33

33VoltAlexander Volta (first battery)Electromotive Force1.5V, 110V, 13.8kVSlide 34

34CurrentNumber of electrons passing every secondAmpere (A) is a unit of current1 A = 6.28 x 1018 electrons/sec

At home: 60A,100AElectronics: 10mASlide 3535AC and DC CurrentsDC: direct currentAC: alternating currentSlide 36

voltvolttime

time36Frequency of AC SignalFrequency = Number of cycles per secondSlide 37

voltvolttimetime

37Experiment!!Whats the highest frequency your eyes can notice?frequency vs. amplitude..790400 terahertz light

Slide 38

38Slide 39

39Closed Loop CircuitsNo current will flow in an open loop circuit..Slide 40

40Closed Loop CircuitsElectric Circuit is a pipeline that facilitates the transfer of charge from one point to anotherSlide 41

41PowerPower is the time rate of change of energy

Unit: watts (W)

P=VISlide 4242Elements supplying Energy vs. Elements absorbing Energy An element in the electric circuit is absorbing energy if +ve current enters the +ve terminal

An element in the electric circuit is supplying energy if +ve current enters the -ve terminal

Slide 4343Ground CurrentsWhy birds do not get shocked by high voltage lines?

How do you charge a weak car battery?Slide 44

44ActivityDetermine the amount of power absorbed or supplied by the elements in the figure?Slide 45I = 2 AV1= 4 V 4 V 45ActivityDetermine the amount of power absorbed or supplied by the elements in the figure?Slide 46I = 4 AV1= 12 V 12 V 46AC SourceGenerally produces sine waveSlide 47

47RMSRMS: Root Mean Squarepower is measured instead of peak voltage

for sine or cosine signals, v(t) = A cos(2pt/T)Slide 48

48RMSIf your meter reads 10V~

then vpeak = 10*1.4 = 14V

If your peak voltage is 154Vp

then the meter reads RMS = 154*0.7 = 110V~Slide 4949More ReadingsBasic Engineering Circuit AnalysisBy J. D. Irwin and R. M. NelmsJohn Wiley & Sons, 2005 or newer editionSlide 5050Electronic ComponentsSection 03ResistorsResists the movement of electronsMeasured in Ohms WHave colored rings to indicate valueSlide 52

52ResistorsSlide 53

53Slide 54Resistors

Temperature coffThe last band on a 6 band resistor is the temperature coefficient of the resistor, measured in PPM/C or parts per million per degree Centigrade. Brown (100 PPM/C) are the most popular, and will work for most reasonable temperature conditions. The others are specially designed for temperature critical applications54ResistorsSlide 555 6 0000 5%560, 000 W or 560 kWtolerance 5%5620 W or 5.62 kWtolerance 10%5 6 2 0 10%55ActivitySlide 56

0 black1 brown2 red3 orange4 yellow5 green6 blue7 violent8 gray9 white

56ResistorsPower RatingPractical resistors are rated according to their maximum power dissipation. Watt, Watt, If the average power dissipated by a resistor is more than its power rating, damage to the resistor may occur, permanently altering its resistance

Slide 5757Parallel and SeriesMore Resistance (Impedance) vs. More Conductance (Admittance)Slide 58

58ActivitySlide 59

59CapacitorsPassive electronic component consisting of a pair of conductors separated by a dielectric (insulator). Temporary Charge Storage DeviceMeasured in Farad (F)Slide 60

timeI60Capacitors Applicationsto block DCto filter noiseto smooth power suppliesto tune radio channelsin memoriesSlide 61

61Parallel and SeriesSlide 62

62Inductors (Coils)Passive electrical component that can store energy in a magnetic field created by the electric current passing through it

Slide 6363Inductors (Coils)Resists (reacts) AC current with delayno effect when DC is usedMeasured in Henry (H)Slide 64

64Parallel and SeriesSlide 65

65Inductors & CapacitorsInductors, capacitors and other components form tuned circuits which can emphasize or filter out specific signal frequencies. Smaller inductor/capacitor combinations provide tuned circuits used in radio reception and broadcasting

Slide 6666FusesProtection devices Current limiting devicesHigh current wire melts open circuitSlide 67

Circuit Symbols67Circuit BreakerRe-usable fuse or switchCurrent increases Stronger Magnet open circuitReset breaker current resumesMagnetic, Thermal, semiconductor breakersSlide 68

Circuit Symbols

68RelaysSwitch to change contact points Controlled via electric currentCurrent in a coil Magnet Pull a metal lever change contactCan be used in turning lights or motors ON/OFFSlide 69

69DiodesConducts current in one directionMany types with different applications

Slide 70

70TransistorsSlide 71

A semiconductor device used to amplify and switch electronic signals. At least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current flowing through another pair of terminals

71First Transistor (1948)

Slide 7272First Electronic Computer

Slide 73ENIAC (1946)73Process TechnologiesSlide 74

74Integrated CircuitsSlide 75

Revolutionized the world of electronics. Used in almost all electronic equipment in use today Low cost of production of IC

Computers, cellular phones, etc.

75First Integrated Circuit (1960)

Slide 76Bipolar Logic76Intel 4004 Processor

Slide 77(1971)

1000 Transistor1MHz77Pentium 4 Processor20003.8 GHz180 nm to 65 nm55 M transistors4 layers metal

Slide 7878Electrical EngineeringUmm Al-Qura UniversitySlide 79

79Other ComponentsEach component does a specific functionEach component has a symbol in circuitsEach component has specificationsSlide 80

80Process CheckSo many components, so what?Are there other important components I should know about?Up to what level should a non-EE engineer get to know the details?Slide 81

81More ReadingsWikipediahttp://en.wikipedia.org/wiki/Main_Page

Slide 82

82Circuit Analysis ISection 0484Basic Laws of CircuitsOhms Law:The voltage across a resistor is directly proportional to the current moving through the resistor.

Directly proportional meansa straight line relationship.v(t)i(t)Rv(t) = Ri(t)8485Two special resistor values

Basic Laws of Circuits8586Basic Laws of CircuitsOhms Law:Example 2.1.

Determine the resistance of the 100 Watt bulb.

8687Basic Laws of Electric CircuitsNodes, Branches, and Loops:We define an electric circuit as: a connection of electricaldevices that form one or more closed paths.Electrical devices can include, but are not limited to,resistors transistors transformerscapacitors logic devices light bulbsinductors switches batteries 8788Basic Laws of Electric CircuitsNodes, Branches, and Loops:A node: is a connection point between two or more branches.A branch: is a single electrical element or device.

Figure : A circuit with 5 branches.

Figure : A circuit with 3 nodes.8889Basic Laws of Electric CircuitsNodes, Branches, and Loops:If we start at any point in a circuit (node), proceed throughconnected electric devices back to the point (node) from which we started, without crossing a node more than one time,we form a closed-path.A loop is a closed-path.An independent loop is one that contains at least one elementnot contained in another loop.8990Basic Laws of Electric CircuitsThe relationship between nodes, branches and loops can be expressed as follows:# branches = # loops + # nodes - 1orB = L + N - 1In using the above equation, the number of loops arerestricted to be those that are independent.In solving most of the circuits in this course, we will notneed to resort to Equation above. However, there are times when itis helpful to use this equation to check our analysis.Nodes, Branches, and Loops:9091Basic Laws of Electric CircuitsConsider the circuit shown in following Figure.

Figure: A multi-loop circuitgive the number of nodesgive the number of independent loopsgive the number of branchesNodes, Branches, and Loops:9192Basic Laws of CircuitsKirchhoffs Current LawAs a consequence of the Law of the conservation of charge, we have:

The sum of the current entering a node (junction point) equal to the sum of the currents leaving.

9293Basic Laws of CircuitsKirchhoffs Current Law The algebraic sum of the currents entering a node equal to zero.

9394Basic Laws of CircuitsKirchhoffs Current LawThe algebraic sum of the currents leaving a node equal to zero.

9495

Basic Laws of CircuitsKirchhoffs Current Law: Example.Find the current I x.Ans: IX =22 A Ix = 22A9596

FIND MISSING CURRENTS by writing KCL equations?KCL DEPENDS ONLY ON THE INTERCONNECTION.THE TYPE OF COMPONENT IS IRRELEVANTKCL DEPENDS ONLY ON THE TOPOLOGY OF THE CIRCUIT9697Kirchhoffs Voltage Law:Basic Laws of Circuits Sum of the voltage drops around a circuit equal zero.We assume a circuit of the following configuration. Notice thatno current has been assumed for this case, at this point.++++____v1v2v4v3Figure9798Basic Laws of CircuitsKirchhoffs Voltage Law:Consideration 1.We define a voltage drop as positive if we enter the positive terminaland leave the negative terminal. +_v1The drop moving from left to right above is + v1.+_v1The drop moving from left to right above is v1.FigureFigure39899Basic Laws of CircuitsKirchhoffs Voltage Law:++++____v1v2v4v3Figure.Consider the circuit of the following FigureIf we sum the voltage drops in the clockwise direction around thecircuit starting at point a we write:- v1 v2 + v4 + v3 = 0- v3 v4 + v2 + v1 = 0adrops in CW direction starting at adrops in CCW direction starting at a499100Basic Laws of CircuitsKirchhoffs Voltage Law: Further details.For the circuit of the following Figure there are a number of closed paths. Three have been selected for discussion.+++++++++++-----------v1v2v4v3v12v11v9v8v6v5v7v10+-Figure:Multi-pathCircuit.Path 1Path 2Path 39100101Basic Laws of CircuitsKirchhoffs Voltage Law: Illustration from Figure.+++++++++++-----------v1v2v4v3v12v11v9v8v6v5v7v10+-aBlue path, starting at a

- v7 + v10 v9 + v8 = 0bRed path, starting at b

+v2 v5 v6 v8 + v9 v11 v12 + v1 = 0Yellow path, starting at b

+ v2 v5 v6 v7 + v10 v11- v12 + v1 = 0Using sum of the drops = 011101102Basic Laws of CircuitsKirchhoffs Voltage Law: Application.Given the circuit of Figure . Find Vad and Vfc.

Using KVL;Vad + 30 15 5 = 0Vad = - 10 VVfc 12 + 30 15 = 0Vfc = - 3 VFigure : Circuit for illustrating KVL.15102103

SAMPLE PROBLEMWe need to find a closed path where only one voltage is unknown

4V103Slide 104

104GCE (A level) Physics E10 Kirchhoff's First Lawhttp://www.youtube.com/watch?v=vtdZcrhGxpM&feature=relatedGCE (A level) Physics E11 Kirchhoff's Second Lawhttp://www.youtube.com/watch?v=fKZ_VydOTQk&feature=relatedGCE (A level) Physics E09 Ohm's Lawhttp://www.youtube.com/watch?v=ZyKTk4xkTas

Slide 105105Circuit Analysis IISection 05Internal ResistanceIf you short a 1.5V battery, how much current will pass?

Slide 107

0.05 ohm 30 AmpersA large current through a battery can cause the rapid buildup of heat, potentially resulting in an explosion or the release ofhydrogengas andelectrolyte(anacidor abase), which can burn tissue, cause blindness or even death107QuestionWhat is the total current drawn from the source?Slide 108

108Voltage DividerElectrical EngineeringUmm Al-Qura UniversitySlide 109

109Current DividerSlide 110

110Multiple LoadsSlide 111

Combine Parallel Loads111Multiple LoadsSlide 112

112Multiple LoadsSlide 113

113Current DividerSlide 114

114Process CheckCalculate all currents in the circuit..What is your plan?!Slide 115

115QuizSlide 116

116Multiple SourcesWhat if more than one source in the circuit?How to solve for all currents?Slide 117

Kvl kal117Nodes and LoopsA Nodea point in a circuit where 3 or more elements meetSlide 118

118Nodes and LoopsHow many nodes in the circuits?Slide 119

119Nodes and LoopsA Loop:a closed ring in a planer circuitSlide 120

120Planar CircuitSlide 121

no branch passes over or under other branch121Voltage DropA current passing through a load generates a voltage dropSlide 122

122KVL and KCL(nodes, loops, planner circuit, voltage drop) then what?

To solve for all currents and volts in a circuit:

KVL: Kirchhoffs Voltage Lawthe algebraic sum of voltages in a loop is zero

KCL: Kirchhoffs Current Lawthe algebraic sum of currents into a node is zeroSlide 123123Circuit Analysiscount nodes minus one (possible ground)mark a current for each branchname and directionwrite KCL equations for each nodecount the loopswrite the KVL equations for each loopsolve for all unknownsSlide 124124ExampleSlide 125

10+-+++---12125ExampleSlide 126

10+-+++---

126ExampleSlide 127

8 branches 8 currents I1..I8 8 equations4 nodes 4 eqs4 loops 4 eqs127HomeWork128Slide 129

HomeWorkI3Q. Find I1, I2, I3 and the voltage on the 4 ohms?129Q. Write all equations required to find I1 I6?Slide 130

HomeWorkI1I2I3I4I5I6130Find V1 , V2 & V3Slide 131

131