electrical engineering department umm al-qura university dr. basim j. zafar

Electrical Engineering department Umm Al-Qura University Dr. Basim J. Zafar

This Course Applications of Electrical Engineering in Different Systems.. Concepts and Basics of Electricity and Electronics.. Practical Engineering Applications.. Slide 2

Course Content History of Electricity Basic Concepts electrons, battery, DC&AC, frequency, closed loop, current, RMS Components R, C, L, fuses, breakers, relays, solenoids, diodes, transistors, ICs Slide 3

Course Content Circuit Analysis ohms law, dividers, KCL, KVL, complex impedance, current source, power Application Specific Circuits Power Generation and Distribution DC machines, transformers, 3-phase systems Slide 4

Course Content Sensors & Actuators resistive, capacitive, inductive special sensors data acquisition Slide 5

Class Format Active Class Teams of 2 students Weekly Quiz (no makeup's) Weekly Activities In-Class Readings Slide 6

Rules Quizzes grades 0 or 10 be ON-TIME absence = -2 no material on table calculator & pencil 2 decimal points with proper units cheating = BIG TROUBLE Slide 7

Rules Activities team ID + members IDs nice fonts and presentation members loads must be equal Teamwork any conflict should be stated from the beginning Slide 8

Grades Quizzes 10% Home Works/ Class Activities 10% Mid Term Exams I15% Mid Term Exams II15% Final 50% Slide 9

Students IDs EE 307 Sections IDs in Teams: Team A: A1 A4. Team B: B1 B4. Team C: C1 C4. Team D: D1 D4. Team E: E1 E4. Slide 10

Class homepage

Section 01

History of Electricity Ancient Egyptian2750 BC shocks from electric fish Slide 13

History of Electricity Romans1500 BC shocks can travel in metals Thales600 BC Noticed static electricity from polishing amber with a piece of wool or fur. Arabs1400 Identity of lightening William Gilbert1600 Coined the New Latin word electricus to refer to the property of attracting small objects after being rubbed Slide 14

History of Electricity Benjamin Franklin1753 lightening key experiment Luigi Galvani1771-1791 nerve cells passed signals to the muscles Alessandro Volta1800 invented the voltaic pile consist of Zinc and silver. Hans Christian rsted 1819 demonstrates electromagnetism. Current flowing in a wire creates a magnetic field which deflects a compass needle. Slide 15

History of Electricity Andr-Marie Ampre 1820 Figures out a way to measure the strength of a magnetic field in relation to an electric current, known as Amperes theorem. Michael Faraday1831 learned how to produce continuous voltage. |This was the first electric motor (generator). Georg Ohm 1827 mathematically analyzed the electrical circuit (ohm's law) Tesla, Edison, Westinghouse, Siemens, 1900s Graham Bell and Kelvin Electricity was turned from a scientific curiosity into an essential tool for modern life (Second Industrial Revolution) Slide 16

Machines Monitoring Slide 17

Fully Programmed Machines Slide 18

Engraving Slide 19

Control Rooms Slide 20

Automation Slide 21

Robots Slide 22

Accuracy Slide 23

ExoMars Mission Slide 24 Life in other planets!

ExoMars Mission Slide 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 levels

ExoMars Mission Slide 26

Printed Circuit Board (PCB) Slide 27

Home Work Process Check, Home Work Ask yourself.. What do I need to know about EE? Make presentation about one of the experiment Slide 28

Section 02

Electrons Atoms and Electrons Slide 30

Is It Like This?! Slide 31

Electricity If electrons were pushed, they produce a current Slide 32

Battery Source of pushing electrons Electrochemical reactions Home Work Look for types of batteries in Wikipedia!! Home Work Slide 33

Volt Alexander Volta (first battery) Electromotive Force 1.5V, 110V, 13.8kV Slide 34

Current Number of electrons passing every second Ampere (A) is a unit of current 1 A = 6.28 x 10 18 electrons/sec At home: 60A,100A Electronics: 10mA Slide 35

AC and DC Currents DC: direct current AC: alternating current Slide 36 volt time

Frequency of AC Signal Frequency = Number of cycles per second Slide 37 volt time

Experiment!! Whats the highest frequency your eyes can notice? frequency vs. amplitude.. 790400 terahertz light Slide 38

Closed Loop Circuits No current will flow in an open loop circuit.. Slide 40

Closed Loop Circuits Electric Circuit is a pipeline that facilitates the transfer of charge from one point to another Slide 41

Power Power is the time rate of change of energy Unit: watts (W) P=VI Slide 42

Elements 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 43

Ground Currents 1. Why birds do not get shocked by high voltage lines? 2. How do you charge a weak car battery? Slide 44

Activity 1. Determine the amount of power absorbed or supplied by the elements in the figure? Slide 45 I = 2 A V 1 = 4 V 4 V

Activity 1. Determine the amount of power absorbed or supplied by the elements in the figure? Slide 46 I = 4 A V 1 = 12 V 12 V

AC Source Generally produces sine wave Slide 47

RMS RMS: Root Mean Square power is measured instead of peak voltage for sine or cosine signals, v ( t ) = A cos( 2 t/T ) Slide 48

RMS If your meter reads 10 V ~ then v peak = 10*1.4 = 14V If your peak voltage is 154 V p then the meter reads RMS = 154*0.7 = 110V~ Slide 49

More Readings Basic Engineering Circuit Analysis By J. D. Irwin and R. M. Nelms John Wiley & Sons, 2005 or newer edition Slide 50

Section 03

Resistors Resists the movement of electrons Measured in Ohms Have colored rings to indicate value Slide 52

Resistors Slide 53

Resistors Temperature coff

Resistors Slide 55 5 6 0000 5% 560, 000 or 560 k tolerance 5% 5620 or 5.62 k tolerance 10% 5 6 2 0 10%

Activity Slide 56 0 black1 brown2 red3 orange4 yellow 5 green6 blue7 violent8 gray9 white

Resistors Power Rating Practical 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 57

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

Activity Slide 59 End of sat lecture

Capacitors Passive electronic component consisting of a pair of conductors separated by a dielectric (insulator). Temporary Charge Storage Device Measured in Farad (F) Slide 60 time I

Capacitors Applications to block DC to filter noise to smooth power supplies to tune radio channels in memories Slide 61

Parallel and Series Slide 62

Inductors (Coils) Passive electrical component that can store energy in a magnetic field created by the electric current passing through it Slide 63

Inductors (Coils) Resists (reacts) AC current with delay no effect when DC is used Measured in Henry (H) Slide 64

Parallel and Series Slide 65

Inductors & Capacitors Inductors, 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 66

Fuses Protection devices Current limiting devices High current wire melts open circuit Slide 67 Circuit Symbols

Circuit Breaker Re-usable fuse or switch Current increases Stronger Magnet open circuit Reset breaker current resumes Magnetic, Thermal, semiconductor breakers Slide 68 Circuit Symbols

Relays Switch to change contact points Controlled via electric current Current in a coil Magnet Pull a metal lever change contact Can be used in turning lights or motors ON/OFF Slide 69

Diodes Conducts current in one direction Many types with different applications Slide 70

Transistors Slide 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

First Transistor (1948) Slide 72

First Electronic Computer Slide 73 ENIAC (1946)

Process Technologies Slide 74

Integrated Circuits Slide 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.

First Integrated Circuit (1960) Slide 76 Bipolar Logic

Intel 4004 Processor Slide 77 (1971) 1000 Transistor 1MHz

Pentium 4 Processor 2000 3.8 GHz 180 nm to 65 nm 55 M transistors 4 layers metal Slide 78

Electrical EngineeringUmm Al-Qura UniversitySlide 79

Other Components Each component does a specific function Each component has a symbol in circuits Each component has specifications Slide 80

Process Check So 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

More Readings Wikipedia http://en.wikipedia.org/wiki/Main_Page Slide 82

Quiz Calculate the Total resistances? Slide 84

Section 04

86 Basic Laws of Circuits Ohms Law: The voltage across a resistor is directly proportional to the current moving through the resistor. Directly proportional means a straight line relationship. v(t) i(t) R v(t) = Ri(t)

87 Two special resistor values Basic Laws of Circuits

88 Basic Laws of Circuits Ohms Law: Example 2.1. Determine the resistance of the 100 Watt bulb.

89 Basic Laws of Electric Circuits Nodes, Branches, and Loops: We define an electric circuit as: a connection of electrical devices that form one or more closed paths. Electrical devices can include, but are not limited to, resistors transistors transformers capacitors logic devices light bulbs inductors switches batteries

90 Basic Laws of Electric Circuits Nodes, 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.

91 Basic Laws of Electric Circuits Nodes, Branches, and Loops: If we start at any point in a circuit (node), proceed through connected 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 element not contained in another loop.

92 Basic Laws of Electric Circuits The relationship between nodes, branches and loops can be expressed as follows: # branches = # loops + # nodes - 1 or B = L + N - 1 In using the above equation, the number of loops are restricted to be those that are independent. In solving most of the circuits in this course, we will not need to resort to Equation above. However, there are times when it is helpful to use this equation to check our analysis. Nodes, Branches, and Loops:

93 Basic Laws of Electric Circuits Consider the circuit shown in following Figure. Figure: A multi-loop circuit give the number of nodes give the number of independent loops give the number of branches Nodes, Branches, and Loops:

94 Basic Laws of Circuits Kirchhoffs Current Law As 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.

95 Basic Laws of Circuits Kirchhoffs Current Law The algebraic sum of the currents entering a node equal to zero.

96 Basic Laws of Circuits Kirchhoffs Current Law The algebraic sum of the currents leaving a node equal to zero.

97 Basic Laws of Circuits Kirchhoffs Current Law: Example. Find the current I x. Ans: I X =22 A

98 FIND MISSING CURRENTS by writing KCL equations? KCL DEPENDS ONLY ON THE INTERCONNECTION. THE TYPE OF COMPONENT IS IRRELEVANT KCL DEPENDS ONLY ON THE TOPOLOGY OF THE CIRCUIT

99 Kirchhoffs 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 that no current has been assumed for this case, at this point. + + + + _ _ _ _ v1v1 v2v2 v4v4 v3v3 Figure

100 Basic Laws of Circuits Kirchhoffs Voltage Law: Consideration 1. We define a voltage drop as positive if we enter the positive terminal and leave the negative terminal. + _v1v1 The drop moving from left to right above is + v 1. + _ v1v1 The drop moving from left to right above is v 1. Figure 3

101 Basic Laws of Circuits Kirchhoffs Voltage Law: + + + + _ _ _ _ v1v1 v2v2 v4v4 v3v3 Figure. Consider the circuit of the following Figure If we sum the voltage drops in the clockwise direction around the circuit starting at point a we write: - v 1 v 2 + v 4 + v 3 = 0 - v 3 v 4 + v 2 + v 1 = 0 a drops in CW direction starting at a drops in CCW direction starting at a 4

102 Basic Laws of Circuits Kirchhoffs Voltage Law: Further details. For the circuit of the following Figure there are a number of closed paths. Three have been selected for discussion. + + + ++ + + + + + + - - - - - - -- - - - v1v1 v2v2 v4v4 v3v3 v 12 v 11 v9v9 v8v8 v6v6 v5v5 v7v7 v 10 + - Figure: Multi-path Circuit. Path 1 Path 2 Path 3 9

103 Basic Laws of Circuits Kirchhoffs Voltage Law: Illustration from Figure. + + + ++ + + + + + + - - - - - - -- - - - v1v1 v2v2 v4v4 v3v3 v 12 v 11 v9v9 v8v8 v6v6 v5v5 v7v7 v 10 + - a Blue path, starting at a - v 7 + v 10 v 9 + v 8 = 0 b Red path, starting at b +v 2 v 5 v 6 v 8 + v 9 v 11 v 12 + v 1 = 0 Yellow path, starting at b + v 2 v 5 v 6 v 7 + v 10 v 11 - v 12 + v 1 = 0 Using sum of the drops = 0 11

104 Basic Laws of Circuits Kirchhoffs Voltage Law: Application. Given the circuit of Figure. Find V ad and V fc. Using KVL; V ad + 30 15 5 = 0 V ad = - 10 V V fc 12 + 30 15 = 0 V fc = - 3 V Figure : Circuit for illustrating KVL. 15

105 SAMPLE PROBLEM We need to find a closed path where only one voltage is unknown 4V

GCE (A level) Physics E10 Kirchhoff's First Law http://www.youtube.com/watch?v=vtdZcrhGxpM&fe ature=related http://www.youtube.com/watch?v=vtdZcrhGxpM&fe ature=related GCE (A level) Physics E11 Kirchhoff's Second Law http://www.youtube.com/watch?v=fKZ_VydOTQk&f eature=related http://www.youtube.com/watch?v=fKZ_VydOTQk&f eature=related GCE (A level) Physics E09 Ohm's Law http://www.youtube.com/watch?v=ZyKTk4xkTas Slide 107

Section 05

Internal Resistance If you short a 1.5V battery, how much current will pass? Slide 110

Question What is the total current drawn from the source? Slide 111

Voltage Divider Electrical EngineeringUmm Al-Qura UniversitySlide 112

Current Divider Slide 113

Multiple Loads Slide 114 Combine Parallel Loads

Multiple Loads Slide 115

Multiple Loads Slide 116

Current Divider Slide 117

Process Check Calculate all currents in the circuit.. What is your plan?! Slide 118

Quiz Slide 119

Multiple Sources What if more than one source in the circuit? How to solve for all currents? Slide 120

Nodes and Loops A Node a point in a circuit where 3 or more elements meet Slide 121

Nodes and Loops How many nodes in the circuits? Slide 122

Nodes and Loops A Loop: a closed ring in a planer circuit Slide 123

Planar Circuit Slide 124

Voltage Drop A current passing through a load generates a voltage drop Slide 125

KVL and KCL (nodes, loops, planner circuit, voltage drop) then what? To solve for all currents and volts in a circuit: KVL: Kirchhoffs Voltage Law the algebraic sum of voltages in a loop is zero KCL: Kirchhoffs Current Law the algebraic sum of currents into a node is zero Slide 126

Circuit Analysis 1.count nodes minus one (possible ground) 2.mark a current for each branch name and direction 3.write KCL equations for each node 4.count the loops 5.write the KVL equations for each loop 6.solve for all unknowns Slide 127

Example Slide 128 1 0 1 2

Example Slide 129 1 0

Example Slide 130 8 branches 8 currents I 1..I 8 8 equations 4 nodes 4 eqs 4 loops 4 eqs

HomeWork I3I3 Q. Find I 1, I 2, I 3 and the voltage on the 4 ohms?

Q. Write all equations required to find I1 I6? Slide 133 HomeWork I1I1 I2I2 I3I3 I4I4 I5I5 I6I6

Find V1, V2 & V3 Slide 134

electrical engineering department umm al-qura university dr. basim j. zafar

Documents