Full representation of the real transformer

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "Full representation of the real transformer"

Transcription

1 TRASFORMERS EQVALET CRCT OF TWO-WDG TRASFORMER TR- Dots show the points of higher potential. There are applied following conventions of arrow directions: -for primary circuit -the passive sign convention (receiver, the power is absorbed), -for secondary circuit - the active sign convention (source, the power is released). Full representation of the real transformer Features: Real transformer with two windings (primary & secondary) of different numbers of turns (usually). Sinusoidal voltage supply. The windings are characterised by their resistances R and R. The magnetic core with power losses and with the main (mutual) flux Φ and leaage fluxes Φ l and Φ l. Primary current and secondary current flow. Electromotive forces due to mutual flux are induced accordingly: E 4.44 fφ E 4.44 fφ Emfs due to leaage fluxes: E x 4.44 fφ l E x 4.44 fφ l Leaage fluxes are directly proportional to currents and and emfs corresponding to leaage fluxes can be represented by the voltage drops at leaage reactances X and X Representation of the transformer by semi-ideal transformer (with no leaage fluxes and zero-resistance winding)

2 REFERRG SECODARY WDG TO PRMARY Secondary circuit referred (recalculated) to primary so as to have the same potential differences Assume that we recalculate secondary emf into new value that will be called secondary emf referred to primary E E 444. fφ 444. fφ E and in the same manner secondary output voltage referred to primary ow the beginnings of primary and secondary windings have the same potentials (E E ) TR-. Connection of two bottom points of the circuit can be done without any consequence as they belong to two separated circuits. The only result of such connection is the equalisation of their potentials.. After recalculation of emfs (E E ) the potentials of the upper points become equal each other. Their connection doesn t lead to the flow of current between them! All referred values are indicated with primes for example R ; X Referred secondary circuit has to represent the real quantities of energy conversion. t means that the values of power and losses cannot be changed in the new model of transformer. Therefore: secondary current referred to primary: secondary resistance referred to primary: R R R R ( ) ( ) and in the same manner secondary reactance referred to primary: X X ( ) The points having the same potentials (E E ) can be connected without any current flow. We have now only one electrical circuit without electrical separation between primary and secondary circuits. How we can represent (by means of electrical circuit) the semi-ideal magnetic core with two identical emfs induced in the windings and with power losses in magnetic circuit?

3 EQVALET (ELECTRCAL) CRCT OF TWO-WDG TRASFORMER TR- 3 o - no-load current f - magnetizing current (reactive component of no-load current) ow - active component of no-load current Parallel branch of this T-type circuit represents the magnetic core of the transformer: iron-core resistance R Fe - the resistance having the value corresponding to power loss in the magnetic circuit, according to relation: P P P + P R o Fe h e Fe ow magnetizing reactance X f - the reactance of primary circuit corresponding to mutual flux and representing primary emf due to relation: E f X f or E jx f f E where: + or + o f ow o f ow Phasor diagram for transformer equivalent circuit: and voltage balance equations: R + jx + E ( R + jx ) + ( R + jx ) +

4 O-LOAD OPERATO AD O-LOAD TEST At no-load state the secondary circuit of the transformer is opened: 0; o Active power supplied to the transformer at no-load state: P o P Cuo + P Fe R o + P Fe o-load loss (power loss not depending on the value of current): P o P Fe P o - R o o-load test of the transformer is easy to be made in laboratory or even in a substation: TR- 4 R induction regulator (voltage source of variable output), A ammeter, V voltmeter, W - wattmeter Measuring circuit diagram During test the supplying voltage is varied from 0 up to (sometimes more). The following quantities are measured: ; ; o ; P o Appropriate characteristics are drawn in the function of primary voltage: Observe the course of o characteristic! Doesn t it loo as magnetizing curve? Try to explain why? Observe also very interesting course of no-load power factor curve. How it can be explain from the physical meaning point of view? otice that no-load power factor value for rated voltage is very low! Basic no-load characteristics From the no-load test results we can determine some parameters of the transformer being tested or its equivalent circuit: P o cosϕ ow o cosϕo f o sinϕo o P RFe X f P P o ow o Fe Rated no-load current (i.e. the value of no-load current at rated voltage) expressed in p.u. or in percent o o or or o % 00% is rather of small value: from a few % in large power transformers to 0-30% in small transformers. f The value of P Fe (iron core loss at nominal voltage) is always given in ratings of transformers or at the nameplates.

5 MAGETZG CRRET HARMOCS Assumption: transformer (at no-load electromagnetic coil) is supplied with the voltage of sinusoidal waveform. This voltage must be balanced by sinusoidal emf induced in the primary winding, hence the flux (flux density) has to be of sine waveform. Determination of no-load current waveform TR- 5 OCDEF magnetic flux density waveform B(t) sinusoidal Φf(i) and Bf(i) must be determined from the characteristic of electromagnetic circuit withsaturation of the core andhysteresis phenomena taen into consideration. C C O from rising-up part of hysteresis loop; E E OL from fallingdown part of hysteresis loop From the figure: i 0 is a sum of active (i 0w ) and reactive (i f magnetising current) components. i f is of non-sinusoidal waveform: i f i f +i f3 +i f5 +i f (odd harmonics, the 3 rd one is the most important from higher order harmonics). Conclusion: n the transformer supplied from sinusoidal voltage source the waveform of magnetizing current absorbed from the same source tends to be disturbed from the sinusoidal pattern at least 3 rd harmonic is required! Question: What can happen when the source cannot provide higher harmonics of current to flow? n such situation the flux (flux density) waveform contains 3 rd and other odd harmonics, therefore emf e waveform is affected by higher harmonics (first of all by 3 rd harmonic). See next figure:

6 SHORT-CRCT STATE, SHORT-CRCT TEST AD PARAMETERS At short circuit the secondary terminals of transformer are shortcircuited. is equal to zero and and can be very high (depending on voltage). They are much higher than o, therefore, after assuming o 0 the equivalent circuit can be simplified: TR- 6 Due to o 0 the parallel branch of the circuit can be neglected. Only series resistances and reactances appear in equivalent circuit. We define the following parameters: short-circuit resistance and reactance R R +R and X X +X short-circuit impedance (sometimes called equivalent impedance of transformer) Z R + jx Z R + X ( Z in short - circuited transf.) Phasor diagram for short-circuited transformer: As X corresponds to leaage fluxes, the saturation effect doesn t affect its value and we can assume that X is constant, independently on current or voltage. t means also that Z const. can be supplemented by R, X, Z triangle (short-circuit impedance) triangle. n laboratory or during field tests the short-circuit tests are very often performed. For the voltage varied from zero up to the value providing the flow of current not too much higher than they are measured: P,, cosϕ and their characteristics drawn:

7 For we determine and specify: short-circuit voltage (having two components: R and X ); P P short-circuit power; cosϕ cosϕ short-circuit power factor. Short-circuit voltage is the value of supplying voltage in shortcircuited transformer that provides a flow of rated currents ( and ). ts value is always shown in ratings of transformers or at the nameplates (usually in p.u. or in %). TR- 7 During test the value of cosϕ can be measured directly by power factor meter or calculated from other values readings: cos ϕ P P S Application of per unit (or relative) values: P Z r ; r ; Pr ; Zr where Z S Z yields: Z r Zr Z Typical percent value of short-circuit voltage is of the following level: - several % for small and medium power transformers, - 0 to 0% for large power transformers (hundreds of MVA). Short-circuit power, i.e. the power absorbed by short-circuited transformer is totally lost in the transformer (the output power P 0). The iron losses in such transformer are much smaller when compared to copper loss and can be neglected. Hence, short-circuit power (absorbed by the transformer with rated current) can be calculated as follows: P R + ( ) R PCu The value of P Cu (rated copper loss, or in other words copper loss at rated load) is always shown in ratings of transformers or at the nameplates. t is easy to prove that: P Cu P 00% Cu % R % PCu % S and other interesting relation concerning the value of short-circuit current flowing in short-circuited transformer supplied with rated voltage (rated short-circuit current): r Z Z r Try to prove it! Practical meaning of this relation is as follows: imagine the transformer having short-circuit voltage0%. n such transformer the shortcircuit current at nominal supplying voltage is 0.

8 TRASFORMER DER LOAD TR- 8 For simplified consideration of the transformer operation under load we can apply its simplified equivalent circuit. Simplification of equivalent circuit (EC) leads to some error much lower when o is smaller in comparison to or currents. Hence, we can use such EC for discussing power transformers fully loaded. sing such model we can consider the problem of output voltage variation for different value and character of the load current. Let us consider the following problem: transformer is supplied with constant primary voltage and the loading current varies. The character of load current is given by its phase angle ϕ varying at closed interval [-90 o, +90 o ]. For 0 the output voltage o. For >0 and some ϕ At this figure the voltage drops triangle is drawn not to the scale. The hypotenuse DC in case of corresponds to the value of and can be few percent of. we observe the voltage drop (difference in voltage values): o CA CB R cosϕ + X sinϕ Assuming and expressing in per units + r o o r r sin o o ( R cosϕ X ϕ ) and for r Rr cosϕ + X r sinϕ Rr cosϕ + Xr sinϕ and final expression for the value of output voltage o r n similar manner, for any value of supply voltage and corresponding value of o we can calculate the output voltage o r or S o r S o Rr R r Xr X r o is no-load output voltage when o is no-load output voltage for

9 The function f(cosϕ ) for is shown in following figure TR- 9 lead leading character of the current, i.e. the current of capacitive character, or current phasor leads the voltage phasor; lag lagging character of the load, inductive load, current phasor lags the voltage phasor. t is seen that max( ) occurs at cosϕ cosϕ i.e. for very special value being a nown parameter of the transformer (short-circuit power factor). Some interesting practical observations can be concluded:. in the transformer fully loaded ( it is very much required not to overload the transformer above its rated current) the voltage drop at internal impedances of the transformer can be maximum (or in p.u. r or % ). For example in the transformer having % 8% the maximum voltage drop (assuming ) can be 8%, i.e. max o 00% 8% o from where it follows that minimum output voltage could be of the value of 8% of o and it would appear for cosϕ cosϕ. For some capacitive loads (leading character of the current) the voltage drop can be of negative value, what means the output voltage at such load can be higher than at no load. magine your transformer having rated voltages 5000/0 V. These voltages are voltage values at no-load. Let your transformer operates as step-down and let it to be supplied with 5 V and fully loaded. Would you lie to have your home appliances to be supplied with the voltage V? Summarising above we can conclude that in the transformer having high value of short-circuit voltage one can expect correspondingly large variation of output voltage with varying load.

Open circuit and short circuit tests on single phase transformer

Open circuit and short circuit tests on single phase transformer 1 Aim Experiment No: 2 Open circuit and short circuit tests on single phase transformer To understand the basic working principle of a transformer. To obtain the equivalent circuit parameters from OC and

More information

Electric Engineering II EE 326 Lecture 4 & 5

Electric Engineering II EE 326 Lecture 4 & 5 Electric Engineering II EE 326 Lecture 4 & 5 Transformers ١ Transformers Electrical transformers have many applications: Step up voltages (for electrical energy transmission with

More information

STUDY OF IDEAL TRANSFORMER AND PRACTICAL TRANSFORMER

STUDY OF IDEAL TRANSFORMER AND PRACTICAL TRANSFORMER STUDY OF IDEAL TRANSFORMER AND PRACTICAL TRANSFORMER RUBY DHANKAR, SAPNA KAMRA,VISHAL JANGRA Abstract- This paper proposes the study of real and ideal transformer. It also explains load, no-load conditions

More information

IVE(TY) Department of Engineering Electrical Machines 1

IVE(TY) Department of Engineering Electrical Machines 1 Hour 8 slide 1 Introduction Transformer Transformer is a machine that has no moving parts but is able to transform alternating voltages and currents from high to low (step-up transformer ) and vice versa

More information

Chapter 5 TRANSFORMERS

Chapter 5 TRANSFORMERS Chapter 5 TRANSFORMERS Objective Understand the transformer nameplate Describe the basic construction features of a transformer. Explain the relationship between voltage, current, impedance, and power

More information

Applying Faraday s law to both the primary and the secondary (noting the possibility of sources applied to either winding), yields

Applying Faraday s law to both the primary and the secondary (noting the possibility of sources applied to either winding), yields TRANSFORMERS Transformers are key elements in power systems. In order to effectively transmit power over long distances without prohibitive line losses, the voltage from the generator (a maximum of output

More information

UNIVERSITY of PENNSYLVANIA DEPARTMENT of ELECTRICAL and SYSTEMS ENGINEERING ESE206 - Electrical Circuits and Systems II Laboratory.

UNIVERSITY of PENNSYLVANIA DEPARTMENT of ELECTRICAL and SYSTEMS ENGINEERING ESE206 - Electrical Circuits and Systems II Laboratory. UNIVERSITY of PENNSYLVANIA DEPARTMENT of ELECTRICAL and SYSTEMS ENGINEERING ESE06 - Electrical Circuits and Systems II Laboratory. Objectives: Transformer Lab. Comparison of the ideal transformer versus

More information

APPLICATION NOTE - 018

APPLICATION NOTE - 018 APPLICATION NOTE - 018 Power Transformers Background Power Transformers are used within an AC power distribution systems to increase or decrease the operating voltage to achieve the optimum transmission

More information

Electrical Machines-I Prof. D. Kastha Department of Electrical Engineering Indian Institute of Technology, Kharagpur

Electrical Machines-I Prof. D. Kastha Department of Electrical Engineering Indian Institute of Technology, Kharagpur Electrical Machines-I Prof. D. Kastha Department of Electrical Engineering Indian Institute of Technology, Kharagpur Lecture - 7 Voltage Regulation of Single Phase Transformers (Refer Slide Time: 00:59)

More information

2. TRANSFORMERS. The main learning objectives for this chapter are listed below. Use equivalent circuits to determine voltages and currents.

2. TRANSFORMERS. The main learning objectives for this chapter are listed below. Use equivalent circuits to determine voltages and currents. . TRANSFORMERS Transformers are commonly used in applications which require the conversion of AC voltage from one voltage level to another. There are two broad categories of transformers: electronic transformers,

More information

Electrical Machines - I Prof. D. Kastha Department of Electrical Engineering Indian Institute of Technology, Kharagpur

Electrical Machines - I Prof. D. Kastha Department of Electrical Engineering Indian Institute of Technology, Kharagpur Electrical Machines - I Prof. D. Kastha Department of Electrical Engineering Indian Institute of Technology, Kharagpur Lecture - 9 Harmonics and Switching Transients in Single Phase Transformers So far

More information

Module 7. Transformer. Version 2 EE IIT, Kharagpur

Module 7. Transformer. Version 2 EE IIT, Kharagpur Module 7 Transformer Version EE IIT, Kharagpur Lesson 4 Practical Transformer Version EE IIT, Kharagpur Contents 4 Practical Transformer 4 4. Goals of the lesson. 4 4. Practical transformer. 4 4.. Core

More information

NZQA registered unit standard 20431 version 2 Page 1 of 7. Demonstrate and apply fundamental knowledge of a.c. principles for electronics technicians

NZQA registered unit standard 20431 version 2 Page 1 of 7. Demonstrate and apply fundamental knowledge of a.c. principles for electronics technicians NZQA registered unit standard 0431 version Page 1 of 7 Title Demonstrate and apply fundamental knowledge of a.c. principles for electronics technicians Level 3 Credits 7 Purpose This unit standard covers

More information

ELEC-E8407 Electromechanics. Laboratory exercise 1: Transformer

ELEC-E8407 Electromechanics. Laboratory exercise 1: Transformer ELEC-E8407 Electromechanics Laboratory exercise 1: Transformer ELEC-E8407 Electromechanics 2 In the exercise, the properties of a core-type transformer are tested by carrying out the following measurements

More information

Chapter 9: Ideal Transformer. 10/9/2003 Electromechanical Dynamics 1

Chapter 9: Ideal Transformer. 10/9/2003 Electromechanical Dynamics 1 Chapter 9: Ideal Transformer 10/9/003 Electromechanical Dynamics 1 Introduction Transformers are one of the most useful electrical devices provides a change in voltage and current levels provides galvanic

More information

7 Testing of Transformers

7 Testing of Transformers 7 Testing of Transformers The structure of the circuit equivalent of a practical transformer is developed earlier. The performance parameters of interest can be obtained by solving that circuit for any

More information

Extra Questions - 1. 1. What current will flow in a 20Ω resistor when it is connected to a 50V supply? a) 0.4A b) 1.6A c) 2.5A

Extra Questions - 1. 1. What current will flow in a 20Ω resistor when it is connected to a 50V supply? a) 0.4A b) 1.6A c) 2.5A Extra Questions - 1 1. What current will flow in a 20Ω resistor when it is connected to a 50V supply? a) 0.4A b) 1.6A c) 2.5A 2. A current of 500mA flows in a resistance of 12Ω. What power is dissipated

More information

Three phase circuits

Three phase circuits Three phase circuits THREE PHASE CIRCUITS THREE-PHASE ADVANTAGES 1. The horsepower rating of three-phase motors and the kva rating of three-phase transformers are 150% greater than single-phase motors

More information

Chapt ha e pt r e r 12 RL Circuits

Chapt ha e pt r e r 12 RL Circuits Chapter 12 RL Circuits Sinusoidal Response of RL Circuits The inductor voltage leads the source voltage Inductance causes a phase shift between voltage and current that depends on the relative values of

More information

Chapter 14. Transformers ISU EE. C.Y. Lee

Chapter 14. Transformers ISU EE. C.Y. Lee Chapter 14 Transformers Objectives Explain mutual inductance Describe how a transformer is constructed and how it works Explain how a step-up and -down transformer works Discuss the effect of a resistive

More information

Functions, variations and application areas of magnetic components

Functions, variations and application areas of magnetic components Westring 18 3314 Büren Germany T +49 951 60 01 0 F +49 951 60 01 3 www.schaffner.com energy efficiency and reliability 1.1 Transformers The transformer is one of the traditional components of electrical

More information

Chapter 12. RL Circuits. Objectives

Chapter 12. RL Circuits. Objectives Chapter 12 RL Circuits Objectives Describe the relationship between current and voltage in an RL circuit Determine impedance and phase angle in a series RL circuit Analyze a series RL circuit Determine

More information

EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 4 - ALTERNATING CURRENT

EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 4 - ALTERNATING CURRENT EDEXCEL NATIONAL CERTIFICATE/DIPLOMA UNIT 5 - ELECTRICAL AND ELECTRONIC PRINCIPLES NQF LEVEL 3 OUTCOME 4 - ALTERNATING CURRENT 4 Understand single-phase alternating current (ac) theory Single phase AC

More information

Electromagnetic Induction

Electromagnetic Induction Electromagnetic Induction "Concepts without factual content are empty; sense data without concepts are blind... The understanding cannot see. The senses cannot think. By their union only can knowledge

More information

Before we proceed with a study of electric machinery, it is desirable to discuss

Before we proceed with a study of electric machinery, it is desirable to discuss CHAPTER 2 Transformers Before we proceed with a study of electric machinery, it is desirable to discuss certain aspects of the theory of magnetically coupled circuits, with emphasis on transformer action.

More information

SYNCHRONOUS MACHINES

SYNCHRONOUS MACHINES SYNCHRONOUS MACHINES The geometry of a synchronous machine is quite similar to that of the induction machine. The stator core and windings of a three-phase synchronous machine are practically identical

More information

Power measurement in balanced 3 phase circuits and power factor improvement. 1 Power in Single Phase Circuits. Experiment no 1

Power measurement in balanced 3 phase circuits and power factor improvement. 1 Power in Single Phase Circuits. Experiment no 1 Experiment no 1 Power measurement in balanced 3 phase circuits and power factor improvement 1 Power in Single Phase Circuits Let v = m cos(ωt) = cos(ωt) is the voltage applied to a R-L circuit and i =

More information

NO LOAD & BLOCK ROTOR TEST ON THREE PHASE INDUCTION MOTOR

NO LOAD & BLOCK ROTOR TEST ON THREE PHASE INDUCTION MOTOR INDEX NO. : M-142 TECHNICAL MANUAL FOR NO LOAD & BLOCK ROTOR TEST ON THREE PHASE INDUCTION MOTOR Manufactured by : PREMIER TRADING CORPORATION (An ISO 9001:2000 Certified Company) 212/1, Mansarover Civil

More information

AS91526: Demonstrate understanding of electrical systems Level 3 Credits 6

AS91526: Demonstrate understanding of electrical systems Level 3 Credits 6 AS956: Demonstrate understanding of electrical systems Level 3 redits 6 This achievement standard involves demonstrating understanding of electrical systems. Achievement riteria Achievement Achievement

More information

ESO 210 Introduction to Electrical Engineering

ESO 210 Introduction to Electrical Engineering ESO 210 Introduction to Electrical Engineering Lecture-22 Transformers 2 After going through this lecture students will be able to answer the following questions. 3 After developing the equivalent circuit

More information

2. A conductor of length 2m moves at 4m/s at 30 to a uniform magnetic field of 0.1T. Which one of the following gives the e.m.f. generated?

2. A conductor of length 2m moves at 4m/s at 30 to a uniform magnetic field of 0.1T. Which one of the following gives the e.m.f. generated? Extra Questions - 2 1. A straight length of wire moves through a uniform magnetic field. The e.m.f. produced across the ends of the wire will be maximum if it moves: a) along the lines of magnetic flux

More information

3 Synchronous Generator Operation

3 Synchronous Generator Operation 3 Synchronous Generator Operation 3.1 Cylindrical Rotor Machine xa xl ra xa E xl ra E Load A (a) (b)phasor diagram for R load xs ra Zs Xs Zs Load (c) φ (d)phasor diagram for R-L load Ι Figure 30: Equivalent

More information

Salman Bin Abdulaziz University College of Engineering. Electrical Engineering Department EE 3360 Electrical Machines (II)

Salman Bin Abdulaziz University College of Engineering. Electrical Engineering Department EE 3360 Electrical Machines (II) CHAPTER # 3 SALIENT-POLE SYNCHRONOUS GENERATOR AND MOTOR 1- Introduction A cylindrical rotor synchronous machines has a uniform air-gap, therefore its reactance remains the same, irrespective of the rotor

More information

INTRODUCTION SELF INDUCTANCE. Introduction. Self inductance. Mutual inductance. Transformer. RLC circuits. AC circuits

INTRODUCTION SELF INDUCTANCE. Introduction. Self inductance. Mutual inductance. Transformer. RLC circuits. AC circuits Chapter 13 INDUCTANCE Introduction Self inductance Mutual inductance Transformer RLC circuits AC circuits Magnetic energy Summary INTRODUCTION Faraday s important contribution was his discovery that achangingmagneticflux

More information

Lab 14: 3-phase alternator.

Lab 14: 3-phase alternator. Lab 14: 3-phase alternator. Objective: to obtain the no-load saturation curve of the alternator; to determine the voltage regulation characteristic of the alternator with resistive, capacitive, and inductive

More information

Reactance and Impedance

Reactance and Impedance Reactance and Impedance Capacitance in AC Circuits Professor Andrew H. Andersen 1 Objectives Describe capacitive ac circuits Analyze inductive ac circuits Describe the relationship between current and

More information

Chapter 10. RC Circuits. Objectives

Chapter 10. RC Circuits. Objectives Chapter 10 RC Circuits Objectives Describe the relationship between current and voltage in an RC circuit Determine impedance and phase angle in a series RC circuit Analyze a series RC circuit Determine

More information

ε rms ε substation HOMEWORK #11 Chapter 29

ε rms ε substation HOMEWORK #11 Chapter 29 HOMEWOK # hapter 9 5 f the frequency in the circuit in Figure 9-8 is doubled, the capacitive reactance of the circuit will (a) double, (b) not change, (c) halve, (d) quadruple. Determine the oncept The

More information

Revision Calcs. 1. The flux produced by a magnet is 10mWb. Determine the flux density if the area of the pole is 250 mm 2

Revision Calcs. 1. The flux produced by a magnet is 10mWb. Determine the flux density if the area of the pole is 250 mm 2 EMA Revision Calcs Miller College Revision Calcs Revision Calcs 1. The flux produced by a magnet is 10mWb. Determine the flux density if the area of the pole is 250 mm 2 2. For the magnet in the previous

More information

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY. EE100 Basics of Electrical

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY. EE100 Basics of Electrical APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY EE100 Basics of Electrical SAMPLE QUESTION PAPER Maximum Marks 100 Part- A (10 questions) Attempt all the questions 10*4=40 1. We have two identical 10 V electromotive

More information

Power System Analysis Prof. A. K. Sinha Department of Electrical Engineering Indian Institute of Technology, Kharagpur. Lecture 2

Power System Analysis Prof. A. K. Sinha Department of Electrical Engineering Indian Institute of Technology, Kharagpur. Lecture 2 Power System Analysis Prof. A. K. Sinha Department of Electrical Engineering Indian Institute of Technology, Kharagpur Lecture 2 (Refer Slide Time: 01:01) Welcome to lesson 2 on Power System Analysis.

More information

THE TRANSFORMER. REFERENCES: PASCO Transformer Notes Physics for Scientists and Engineers, Tipler, 4 th Ed., Vol. 2 INTRODUCTION.

THE TRANSFORMER. REFERENCES: PASCO Transformer Notes Physics for Scientists and Engineers, Tipler, 4 th Ed., Vol. 2 INTRODUCTION. THE TRANSFORMER LAB ELEC 7 REFERENCES: PASCO Transformer Notes Physics for Scientists and Engineers, Tipler, 4 th Ed., Vol. 2 NTRODUCTON Nearly all of today s electrical energy is produced as alternating

More information

Alternating Current. Asist. Prof. Dr. Aytaç Gören Asist. Prof. Dr. Levent Çetin

Alternating Current. Asist. Prof. Dr. Aytaç Gören Asist. Prof. Dr. Levent Çetin Asist. Prof. Dr. Aytaç Gören Asist. Prof. Dr. Levent Çetin 30.10.2012 Contents Alternating Voltage Phase Phasor Representation of AC Behaviors of Basic Circuit Components under AC Resistance, Reactance

More information

Basic AC Reactive Components IMPEDANCE

Basic AC Reactive Components IMPEDANCE Basic AC Reactive Components Whenever inductive and capacitive components are used in an AC circuit, the calculation of their effects on the flow of current is important. EO 1.9 EO 1.10 EO 1.11 EO 1.12

More information

Electricity. Voltage and current transformation with a transformer. LD Physics Leaflets P Electromagnetic induction Transformer

Electricity. Voltage and current transformation with a transformer. LD Physics Leaflets P Electromagnetic induction Transformer Electricity Electromagnetic induction Transformer LD Physics Leaflets Voltage and current transformation with a transformer P3.4.5. Objects of the experiment g Measuring the secondary voltage of an unloaded

More information

Chapter 8. Introduction to Alternating Current and Voltage. Objectives

Chapter 8. Introduction to Alternating Current and Voltage. Objectives Chapter 8 Introduction to Alternating Current and Voltage Objectives Identify a sinusoidal waveform and measure its characteristics Describe how sine waves are generated Determine the various voltage and

More information

Fall 12 PHY 122 Homework Solutions #10

Fall 12 PHY 122 Homework Solutions #10 Fall 12 PHY 122 Homework Solutions #10 HW10: Ch.30 Q5, 8, 15,17, 19 P 1, 3, 9, 18, 34, 36, 42, 51, 66 Chapter 30 Question 5 If you are given a fixed length of wire, how would you shape it to obtain the

More information

PHASOR DIAGRAMS HANDS-ON RELAY SCHOOL WSU PULLMAN, WA. RON ALEXANDER - BPA

PHASOR DIAGRAMS HANDS-ON RELAY SCHOOL WSU PULLMAN, WA. RON ALEXANDER - BPA PHASOR DIAGRAMS HANDS-ON RELAY SCHOOL WSU PULLMAN, WA. RON ALEXANDER - BPA What are phasors??? In normal practice, the phasor represents the rms maximum value of the positive half cycle of the sinusoid

More information

7.1 POWER IN AC CIRCUITS

7.1 POWER IN AC CIRCUITS C H A P T E R 7 AC POWER he aim of this chapter is to introduce the student to simple AC power calculations and to the generation and distribution of electric power. The chapter builds on the material

More information

Faculty of Engineering and Information Technology. Lab 3 Transformers

Faculty of Engineering and Information Technology. Lab 3 Transformers Faculty of Engineering and Information Technology Subject: 485 Fundamentals of Electrical Engineering Assessment umber: 3 Assessment Title: Lab 3 Transformers Tutorial Group: Students ame(s) and umber(s)

More information

Chapter 12. RL Circuits ISU EE. C.Y. Lee

Chapter 12. RL Circuits ISU EE. C.Y. Lee Chapter 12 RL Circuits Objectives Describe the relationship between current and voltage in an RL circuit Determine impedance and phase angle in a series RL circuit Analyze a series RL circuit Determine

More information

EXPERIMENT 4:- MEASUREMENT OF REACTANCE OFFERED BY CAPACITOR IN DIFFERENT FREQUENCY FOR R-C CIRCUIT

EXPERIMENT 4:- MEASUREMENT OF REACTANCE OFFERED BY CAPACITOR IN DIFFERENT FREQUENCY FOR R-C CIRCUIT Kathmandu University Department of Electrical and Electronics Engineering BASIC ELECTRICAL LAB (ENGG 103) EXPERIMENT 4:- MEASUREMENT OF REACTANCE OFFERED BY CAPACITOR IN DIFFERENT FREQUENCY FOR R-C CIRCUIT

More information

Prof. Anchordoqui Problems set # 11 Physics 169 May 5, 2015

Prof. Anchordoqui Problems set # 11 Physics 169 May 5, 2015 rof. Anchordoqui roblems set # hysics 69 May 5, 5. A semicircular conductor of radius.5 m is rotated about the axis A at a constant rate of rev/min (Fig. ). A uniform magnetic field in all of the lower

More information

Lecture 5: Transformers(continued)

Lecture 5: Transformers(continued) Lecture 5: Transformers(continued) Equivalent circuit of a transformer Figure (1) shows an equivalent circuit of a transformer. R 1 and R 2 represent the resistances of the primary and secondary windings

More information

Copper and Electricity: Generation

Copper and Electricity: Generation PHYSICS Copper and Electricity: Generation (Electromagnetic Induction) 16-18 YEARS Below are different sections of this e-source, for quick navigation. Electricity from Movement What is Induction? Flux

More information

Unit 8: Electromagnetic Induction

Unit 8: Electromagnetic Induction Unit 8: Electromagnetic nduction Electromagnetic induction phenomena. Faraday s law and enz s law. Examples of Faraday s and enz s laws. Mutual inductance and self-inductance. Stored energy on an inductor.

More information

On-site Measurement, Suppressing and Assessment of Inrush Currents in a 1000kV UHV Transformer, with Consideration of Core Saturation.

On-site Measurement, Suppressing and Assessment of Inrush Currents in a 1000kV UHV Transformer, with Consideration of Core Saturation. 21, rue d Artois, F-75008 PARIS A2_305_2012 CIGRE 2012 http : //www.cigre.org On-site Measurement, Suppressing and Assessment of Inrush Currents in a 1000kV UHV Transformer, with Consideration of Core

More information

: Off-Load, Loaded, Short-circuit. Objectives:

: Off-Load, Loaded, Short-circuit. Objectives: EXPERIMENT 3: Single Phase Transformer Part A : Off-Load, Loaded, Short-circuit Objectives: 1. Operate a single phase transformer off-load, with a load applied and with a short circuit applied 2. Deduce

More information

Basic Electrical Technology Dr. L. Umanand Department of Electrical Engineering Indian Institute of Science, Bangalore. Lecture - 33 3 phase System 4

Basic Electrical Technology Dr. L. Umanand Department of Electrical Engineering Indian Institute of Science, Bangalore. Lecture - 33 3 phase System 4 Basic Electrical Technology Dr. L. Umanand Department of Electrical Engineering Indian Institute of Science, Bangalore Lecture - 33 3 phase System 4 Hello everybody. So, in the last class we have been

More information

Name: Lab Partner: Section: The purpose of this lab is to study induction. Faraday s law of induction and Lenz s law will be explored.

Name: Lab Partner: Section: The purpose of this lab is to study induction. Faraday s law of induction and Lenz s law will be explored. Chapter 8 Induction - Faraday s Law Name: Lab Partner: Section: 8.1 Purpose The purpose of this lab is to study induction. Faraday s law of induction and Lenz s law will be explored. 8.2 Introduction It

More information

Chapter 11. Inductors. Objectives

Chapter 11. Inductors. Objectives Chapter 11 Inductors Objectives Describe the basic structure and characteristics of an inductor Discuss various types of inductors Analyze series inductors Analyze parallel inductors Analyze inductive

More information

Electromagnetic Induction - A

Electromagnetic Induction - A Electromagnetic Induction - A APPARATUS 1. Two 225-turn coils 2. Table Galvanometer 3. Rheostat 4. Iron and aluminum rods 5. Large circular loop mounted on board 6. AC ammeter 7. Variac 8. Search coil

More information

Laboratory #2: AC Circuits, Impedance and Phasors Electrical and Computer Engineering EE University of Saskatchewan

Laboratory #2: AC Circuits, Impedance and Phasors Electrical and Computer Engineering EE University of Saskatchewan Authors: Denard Lynch Date: Aug 30 - Sep 28, 2012 Sep 23, 2013: revisions-djl Description: This laboratory explores the behaviour of resistive, capacitive and inductive elements in alternating current

More information

USER MANUAL THE RESOLVER

USER MANUAL THE RESOLVER USR MANUAL TH RSOLVR ICP Department 4 has developed and produced a wide range of transmitter type resolvers for military and industrial applications. From a mechanical viewpoint, these products have been

More information

1. Title Electrical fundamentals II (Mechanics Repair and Maintenance)

1. Title Electrical fundamentals II (Mechanics Repair and Maintenance) 1. Title Electrical fundamentals II (Mechanics Repair and Maintenance) 2. Code EMAMBG429A 3. Range The knowledge is needed for a wide range of aircraft repair and maintenance works,e.g. applicable to aircrafts,

More information

Basic Electrical Theory

Basic Electrical Theory Basic Electrical Theory Power Principles and Phase Angle PJM State & Member Training Dept. PJM 2014 10/24/2013 Objectives At the end of this presentation the learner will be able to; Identify the characteristics

More information

Digital Energy ITI. Instrument Transformer Basic Technical Information and Application

Digital Energy ITI. Instrument Transformer Basic Technical Information and Application g Digital Energy ITI Instrument Transformer Basic Technical Information and Application Table of Contents DEFINITIONS AND FUNCTIONS CONSTRUCTION FEATURES MAGNETIC CIRCUITS RATING AND RATIO CURRENT TRANSFORMER

More information

ALTERNATING CURRENTS

ALTERNATING CURRENTS ALTERNATING CURRENTS VERY SHORT ANSWER QUESTIONS Q-1. What is the SI unit of? Q-2. What is the average value of alternating emf over one cycle? Q-3. Does capacitor allow ac to pass through it? Q-4. What

More information

DHANALAKSHMI COLLEGE OF ENGINEERING DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING EE2302 - ELECTRICAL MACHINES II UNIT-I SYNCHRONOUS GENERATOR

DHANALAKSHMI COLLEGE OF ENGINEERING DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING EE2302 - ELECTRICAL MACHINES II UNIT-I SYNCHRONOUS GENERATOR 1 DHANALAKSHMI COLLEGE OF ENGINEERING DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING Constructional details Types of rotors EE2302 - ELECTRICAL MACHINES II UNIT-I SYNCHRONOUS GENERATOR PART A 1.

More information

The Synchronous Machine

The Synchronous Machine Experiment No. 5 The Synchronous Machine Synchronous ac machines find application as motors in constant speed applications and, when interfaced to the power source with a variable-frequency converter system,

More information

Supplementary Notes on Transformers

Supplementary Notes on Transformers Supplementary Notes on Transformers A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors the transformer's coils. Figure 1 illustrates

More information

Einstein Classes, Unit No. 102, 103, Vardhman Ring Road Plaza, Vikas Puri Extn., Outer Ring Road, New Delhi , Ph. : ,

Einstein Classes, Unit No. 102, 103, Vardhman Ring Road Plaza, Vikas Puri Extn., Outer Ring Road, New Delhi , Ph. : , 1 EMI & AC 1. Derive an expression for the impendance of a coil in AC ciruit. A current of 1.1 A flows through a coil when connected to a 110 V DC. When 110 V AC of 50 Hz is applied to the same coil, only

More information

SINGLE PHASE TRANSFORMER MAGNETIC CIRCUIT AND ELECTRIC TRANSFORMER PART1: FAMILIARIZATION

SINGLE PHASE TRANSFORMER MAGNETIC CIRCUIT AND ELECTRIC TRANSFORMER PART1: FAMILIARIZATION Islamic University of Gaza Faculty of Engineering Electrical Engineering department Electric Machine Lab Eng. Omar A. Qarmout Eng. Amani S. Abu Reyala Experiment 3 SINGLE PHASE TRANSFORMER MAGNETIC CIRCUIT

More information

LIST OF EXPERIMENTS BASIC ELECTRICAL ENGINEERING

LIST OF EXPERIMENTS BASIC ELECTRICAL ENGINEERING IST OF EXPERIMETS BASIC EECTRICA EGIEERIG 1. To verify KC and K. To study the -I characteristics of an incandescent lamp. 3. To measure single phase power by using three ammeter method. 4. To measure the

More information

Chapter 24. Three-Phase Voltage Generation

Chapter 24. Three-Phase Voltage Generation Chapter 24 Three-Phase Systems Three-Phase Voltage Generation Three-phase generators Three sets of windings and produce three ac voltages Windings are placed 120 apart Voltages are three identical sinusoidal

More information

Chapter 15 10/14/2014

Chapter 15 10/14/2014 Chapter 15 Analyze series and parallel ac circuits to find Voltage Current Power Total impedance, admittance Apply known circuit theories Kirchhoff s current, voltage laws Voltage or current divider rule

More information

Simple Harmonic Motion: AC circuits: alternating current electricity

Simple Harmonic Motion: AC circuits: alternating current electricity Simple Harmonic Motion: AC circuits: alternating current electricity Alternating current (AC) circuits explained using time and phasor animations. Impedance, phase relations, resonance and RMS quantities.

More information

TRANSFORMER: THREE PHASE

TRANSFORMER: THREE PHASE CONTENTS Transformer : Three Phase 1211 C H A P T E R 33 Learning Objectives Three-phase Transformers Three-phase Transformer Connections Star/Star or Y/Y Connection Delta-Delta or Connection Wye/Delta

More information

* Self-inductance * Mutual inductance * Transformers. PPT No. 32

* Self-inductance * Mutual inductance * Transformers. PPT No. 32 * Self-inductance * Mutual inductance * Transformers PPT No. 32 Inductance According to Faraday s Electromagnetic Induction law, induction of an electromotive force occurs in a circuit by varying the magnetic

More information

Student Name Instructor Name. High School or Vocational Center Grade. COMPETENCY RECORD FOR ARTICULATION Muskegon Community College Electronics

Student Name Instructor Name. High School or Vocational Center Grade. COMPETENCY RECORD FOR ARTICULATION Muskegon Community College Electronics Student Name Instructor Name High School or Vocational Center Grade COMPETENCY RECORD FOR ARTICULATION Muskegon Community College Electronics Please check below each skill the student has mastered as described,

More information

DOE FUNDAMENTALS HANDBOOK ELECTRICAL SCIENCE Volume 4 of 4

DOE FUNDAMENTALS HANDBOOK ELECTRICAL SCIENCE Volume 4 of 4 DOE-HDBK-1011/4-92 JUNE 1992 DOE FUNDAMENTALS HANDBOOK ELECTRICAL SCIENCE Volume 4 of 4 U.S. Department of Energy Washington, D.C. 20585 FSC-6910 Distribution Statement A. Approved for public release;

More information

Three-Phase A.C. Circuits

Three-Phase A.C. Circuits Chapter 3 Three-Phase A.C. Circuits earning Outcomes This chapter introduces the concepts and principles of the three-ase electrical supply, and the corresponding circuits. On completion you should be

More information

AC Motor, Transformers, Instruments & Distribution Systems Course# EE604

AC Motor, Transformers, Instruments & Distribution Systems Course# EE604 AC Motor, Transformers, Instruments & Distribution Systems Course# EE604 EZpdh.com All Rights Reserved DOE-HDBK-1011/4-92 JUNE 1992 DOE FUNDAMENTALS HANDBOOK ELECTRICAL SCIENCE Volume 4 of 4 U.S. Department

More information

The current that flows is determined by the potential difference across the conductor and the resistance of the conductor (Ohm s law): V = IR P = VI

The current that flows is determined by the potential difference across the conductor and the resistance of the conductor (Ohm s law): V = IR P = VI PHYS1000 DC electric circuits 1 Electric circuits Electric current Charge can move freely in a conductor if an electric field is present; the moving charge is an electric current (SI unit is the ampere

More information

Chapter 35 Alternating Current Circuits

Chapter 35 Alternating Current Circuits hapter 35 Alternating urrent ircuits ac-ircuits Phasor Diagrams Resistors, apacitors and nductors in ac-ircuits R ac-ircuits ac-ircuit power. Resonance Transformers ac ircuits Alternating currents and

More information

TRANSFORMER CONSTRUCTION

TRANSFORMER CONSTRUCTION TRANSFORMER CONSTRUCTION A transformer consists of two windings coupled through a magnetic medium. The two windings work at different voltage level. The two windings of the transformer are called High

More information

Inductors in AC Circuits

Inductors in AC Circuits Inductors in AC Circuits Name Section Resistors, inductors, and capacitors all have the effect of modifying the size of the current in an AC circuit and the time at which the current reaches its maximum

More information

Edmund Li. Where is defined as the mutual inductance between and and has the SI units of Henries (H).

Edmund Li. Where is defined as the mutual inductance between and and has the SI units of Henries (H). INDUCTANCE MUTUAL INDUCTANCE If we consider two neighbouring closed loops and with bounding surfaces respectively then a current through will create a magnetic field which will link with as the flux passes

More information

CHAPTER 3 INDUCTION MOTOR AND DIFFERENT SPEED CONTROL METHODS

CHAPTER 3 INDUCTION MOTOR AND DIFFERENT SPEED CONTROL METHODS CHAPTER 3 INDUCTION MOTOR AND DIFFERENT SPEED CONTROL METHODS Page No 3.1 Introduction 58 3.2 Three Phase Induction Motor 58 3.2.1 Stator 60 3.2.2 Rotor 60 3.2.3 Working principle of three phase induction

More information

AP Physics C Chapter 23 Notes Yockers Faraday s Law, Inductance, and Maxwell s Equations

AP Physics C Chapter 23 Notes Yockers Faraday s Law, Inductance, and Maxwell s Equations AP Physics C Chapter 3 Notes Yockers Faraday s aw, Inductance, and Maxwell s Equations Faraday s aw of Induction - induced current a metal wire moved in a uniform magnetic field - the charges (electrons)

More information

Coupled Inductors. Introducing Coupled Inductors

Coupled Inductors. Introducing Coupled Inductors Coupled Inductors From power distribution across large distances to radio transmissions, coupled inductors are used extensively in electrical applications. Their properties allow for increasing or decreasing

More information

ELECTRICAL ENGINEERING Vol. I - Direct Current and Alternating Current Systems - N. Rajkumar DIRECT CURRENT AND ALTERNATING CURRENT SYSTEMS

ELECTRICAL ENGINEERING Vol. I - Direct Current and Alternating Current Systems - N. Rajkumar DIRECT CURRENT AND ALTERNATING CURRENT SYSTEMS DIRECT CURRENT AND ALTERNATING CURRENT SYSTEMS N. Rajkumar, Research Fellow, Energy Systems Group, City University Northampton Square, London EC1V 0HB, UK Keywords: Electrical energy, direct current, alternating

More information

Eðlisfræði 2, vor 2007

Eðlisfræði 2, vor 2007 [ Assignment View ] [ Pri Eðlisfræði 2, vor 2007 31. Alternating Current Circuits Assignment is due at 2:00am on Wednesday, March 21, 2007 Credit for problems submitted late will decrease to 0% after the

More information

DIRECT CURRENT GENERATORS

DIRECT CURRENT GENERATORS DIRECT CURRENT GENERATORS Revision 12:50 14 Nov 05 INTRODUCTION A generator is a machine that converts mechanical energy into electrical energy by using the principle of magnetic induction. This principle

More information

Application Note. So You Need to Measure Some Inductors?

Application Note. So You Need to Measure Some Inductors? So You Need to Measure Some nductors? Take a look at the 1910 nductance Analyzer. Although specifically designed for production testing of inductors and coils, in addition to measuring inductance (L),

More information

Chapter 31. Faraday s Law

Chapter 31. Faraday s Law Chapter 31 Faraday s Law Michael Faraday 1791 1867 British physicist and chemist Great experimental scientist Contributions to early electricity include: Invention of motor, generator, and transformer

More information

13 ELECTRIC MOTORS. 13.1 Basic Relations

13 ELECTRIC MOTORS. 13.1 Basic Relations 13 ELECTRIC MOTORS Modern underwater vehicles and surface vessels are making increased use of electrical actuators, for all range of tasks including weaponry, control surfaces, and main propulsion. This

More information

MAGNETISM MAGNETISM. Principles of Imaging Science II (120)

MAGNETISM MAGNETISM. Principles of Imaging Science II (120) Principles of Imaging Science II (120) Magnetism & Electromagnetism MAGNETISM Magnetism is a property in nature that is present when charged particles are in motion. Any charged particle in motion creates

More information

ECVET Curriculum UNIT TEMPLATE. Electrotechnology and Applications Unit Type (e.g. major, minor, elective): Unit Level: EQF Level 5

ECVET Curriculum UNIT TEMPLATE. Electrotechnology and Applications Unit Type (e.g. major, minor, elective): Unit Level: EQF Level 5 Institution: IEK DELTA Programme/Training Title: Domestic Electrical Installations Technician Unit Title: Electrotechnology and Applications Unit Type (e.g. major, minor, elective): Core Unit Level: EQF

More information

Efficiency of a Transformer. (a) copper losses: These occur in the transformer primary and secondary windings. They may be calculated from R 2

Efficiency of a Transformer. (a) copper losses: These occur in the transformer primary and secondary windings. They may be calculated from R 2 Efficiency of a Transfmer The losses that take place in a transfmer on load can be divided into two groups (a) copper losses: These occur in the transfmer primary and secondary windings. They may be calculated

More information