U of I Seminar Page 1 TAK 9 / 16 / Inductions Motors
|
|
- Pearl Briggs
- 6 years ago
- Views:
Transcription
1 U of I Seminar Page 1 TAK 9 / 16 / 2016 Inductions Motors Overview of history, physical design, basic theory, and performance with emphasis on aircraft applications Typical large induction motor circa HP 8 pole 600 RPM must be 40 hertz Drip proof, self vent Formed coil / chain wound / single coil per slot (consequent pole) Wound rotor with spider construction Slip rings outboard of bearing Sleeve bearing
2 U of I Seminar Page 2 TAK 9 / 16 / Description, configuration, features Other names are asynchronous or squirrel cage motor Only one of the windings is excited with electrical input as a requirement Does it even have a winding on the rotor? It s like a transformer with an air gap and the secondary is shorted out and spins It s like a clutch being ridden all the time It s simple and robust It s synonymous with 3 phase, polyphase, and rotary magnetic field One of the 10 best discoveries in the last 130 years. It s not just a motor it s a brake or a generator Tesla s first motor 2 phase (4 wire) 2 pole Concentrated or concentric pole wound Wound rotor shorted
3 U of I Seminar Page 3 TAK 9 / 16 / 2016 The second Tesla motor Gramme ring wound stator Slotted 6 pole? Solid rotor 2 phase (4 wire) Induction motors comprise of the following electrical / magnetic elements: Stator the only part normally connected to external electrical power. Most commonly on the exterior and almost always stationary. Stator winding are three phase or single phase today and carry full power of the motor. Stators have laminated cores and most have slots for the coils either formed coils or random wound coils. It s hard to tell induction motor and traditional synchronous stators apart. Early machines quickly moved to the modern stator configuration.
4 U of I Seminar Page 4 TAK 9 / 16 / 2016 Rotor the rotor need not receive external power or excitation other than from the stator. Most rotors are squirrel cage consisting of bars that are shorted together on each end to end rings. Cage rotors are cast or fabricated of aluminum, copper, or other metals. Most rotors have no insulation. Wound rotors have winding schemes similar to stators typically wound for 3 phases and with a pole count matching the stator. Slip rings are used to connect a wound rotor to external resistance to change the motor speed / torque characteristic. Early Tesla / Westinghouse 2 phase wound rotor motor 8 concentric coils on pole pieces 2 phase 4 poles (2 coils per pole) 2 slip rings
5 U of I Seminar Page 5 TAK 9 / 16 / phase formed coil stator and matching rotor Transition to 3 phase and many slotted distributed winding This machine is formed coil, concentric, consequent, and chain wound 15 coil groups, 5 per phase note 1 group has a special cross over 10 pole, 120 slot, 4 slots per pole per phase Small slot opening to reduce slot leakage but coils inserted from ends Circa 1900 Matching squirrel cage rotor 2 radial vents rotor and stator) Fabricated construction Note open slot tops 90 slots (originally wound?) How many phases or poles??
6 U of I Seminar Page 6 TAK 9 / 16 / 2016 Core configuration Barrel slotted, Gramme ring, or concentrated pole wound Slot type Stator Winding Basics Parallel side formed coil Semi closed ( parallel tooth) random winding Coil shape Loop wound or wave wound
7 U of I Seminar Page 7 TAK 9 / 16 / 2016 Layers 2 layer lap 3 groups per pole if 60 degree belts or 3 groups per pole pair if 120 degree belts (low speed of 2 speed motors) 1 layer 3 groups per pole pair since half as many groups can be called consequent pole Loop shape Knuckled lap coils Concentric / chain coils Winding repetition Integral winding slot per pole per phase ( s/p/ph) is an integer all groups have same # of coils in series no restrictions in parallels Fractional winding s/p/ph is a fraction parallels limited
8 U of I Seminar Page 8 TAK 9 / 16 / 2016 Integral example 6 pole 54 slots (60 degree belts, 2 layer) = 54 s/p/ph = coil groups all the same coil groups per phase , 3, 2, or 1 parallels available Fractional example 8 pole 90 slots (60 degree belts, 2 layer) = 90 s/p/ph = coil groups not all the same coil groups per phase , or 1 parallels available Always 4 groups in series = 11 = 3.75 x 4 Winding factors Pitch factor Kp: Coil embrace, pitch, or throw what part of pole pitch is covered. Sine of 90 degrees x embrace. Distribution factor Kd phase effect of adjacent coils in a group in series never less than 3/π (.955) for 60 degree belts. Connection parallel groups, series groups, wye or delta. Example 36 slot / 4 pole / 2 layer lap winding s/p/ph = 36 / 4 / 3 = 3 3 turn coils / 2 parallel Y / 1 to 7 throw pole pitch = 36 / 4 = 9 coil pitch = (7 1) / 9 =.67 kp= sin ( 90 x.67) =.866 kd = groups per phase since 2 parallel there are two groups in series Series turns = 4 turn x 3 coils per group x 2 groups in series x.866 x.96 = 19.95
9 U of I Seminar Page 9 TAK 9 / 16 / 2016 Partially wound formed coil stator Lap wound 2 coil sides per slot Bar wound = 1 turn = 1 knuckle Multi turn 2 knuckle Multi turn formed coils with corona gradient paint in core area. Stator coil at loop stage and after spreading 2 four turn coils in slot, without and with side ways stranding
10 U of I Seminar Page 10 TAK 9 / 16 / 2016 Random wound stators in process Aircraft hydraulic pump motor Random lap wound Semi closed slots Parallel teeth Note phase papers
11 U of I Seminar Page 11 TAK 9 / 16 / 2016 Rotor Construction Wound rotor Bar wound Maybe 4 pole because coil end turn crosses about 1/8 th of circumference. Bar to bar connection will be soldered using clips. First motor I ever wound was like this in Took me 3 weeks. Traditional fabricated bar rotor are used for: 1. High efficiency (copper bar) 2. Large size Copper trade groups tout the advantages of copper rotors aluminum rotors have bad efficiency Fabricated rotor have brazed or soldered connection and potentially loose bars. They are most prone to rotor problems Is efficiency always a good thing? Rotor slot combo crib sheetblack art at its best. Refer to Gabriel Kron, AIEE, 1931
12 U of I Seminar Page 12 TAK 9 / 16 / HP rotor 6 pole machine Die cast aluminum ½ slot stator skew Open slot tops Double tear drop design 65 slot (13 x 5) 56 slot stator (6 pole x 3 phase x 3 slots/pole/ph = 54) 65 / 54 = 1.20 (greater than 1.2 or less than.8) R S = 9 (not 6, 6+/ 1, or 6+/ 2) Comparison of moderate and deep bar designs Slot opening carter factor for effective air gap Slot leakage (reactance) Various depth over width ratios Skin effect Deep bar effect Rotor reactance and resistance varies with slip / speed
13 U of I Seminar Page 13 TAK 9 / 16 / Theory and some history The transformer analogy Rotary magnetic field Force mechanism Logic, slip, and the equivalent circuit
14 U of I Seminar Page 14 TAK 9 / 16 / 2016 The rotating magnetic field The first AC machines were alternators (synchronous machines) but these machines were conceived as an AC replacement for DC dynamos. They were 2 wire machines that essentially replaced the commutator of a DC machine with slip rings. Then the ideal came to place this new type AC winding on the stator. The alternator was the necessary companion to the transformer for long distance transmission. Early alternator with dynamo exciter disc wound design Field stationary Armature rotating with slip rings single ckt First Commercial 3 phase alternator, claw tooth rotor Lauffen to Frankfort system 110 miles 32 pole, 40 hertz, 2000 volt, 50 volt, 1400 amp 93 hertz at 400 RPM, weighs 9 tons To date no one had tried to operate these machines as motors nor had they been paralleled. Frequency was not important because nothing operated off frequency. Early machines were single phase there was no concept of multiple or polyphases.
15 U of I Seminar Page 15 TAK 9 / 16 / 2016 Galileo Ferraris and Tesla theorized that AC current with a fixed phase relationship (polyphase) could be placed about a machine geometrically such that these pulsating MMF s would result in a wave that rotates about the machine and allow inducted excitation of a rotor across the air gap. Phase A MMF in a machine Phase B MMF in a machine 120 degrees away from A Phase C MMF in a machine 120 degrees away from B Resultant MMF wave moving or travelling
16 U of I Seminar Page 16 TAK 9 / 16 / 2016 The result of this idea lead to 3 advancements: 1. The idea that polyphases would allow for a traveling MMF that could be put to use. Mikhail Dolivo Dobrovolsky showed three phases (Drehstrom) was more practical than two phase. AC was already identified as having a separate advantage because it allowed high voltage distribution via transformers. 2. The invention of the induction motor nearly simultaneously by Galileo Ferraris and Tesla. (Later Mikhail Dolivo Dobrovolsky simplified the motor with the squirrel cage rotor.) 3. The understanding that the alternator could also operate as a synchronous motor. Tesla or Ferraris and who else? Walter Bailey 1879 demonstrated a 2 phase device powered by dry cells and a hand crank commutator. Ferraris demonstrated polyphase and rotating magnetic fields in He built induction type motor prior to Tesla. Tesla received a US patent on May 1 st He made great prototypes and presented the motor like a showman at technical gatherings. Dolivo Dobrovolsky added a lot to practicality 3 phase theory and rotor construction. Behrend and De La Tour published practical theory and the circle diagram in Steinmetz provided the equivalent circuit we use today replacing the more complete Heyland circle diagram. By 1911, Bailey s book The induction Motor summarizes modern theory.
17 U of I Seminar Page 17 TAK 9 / 16 / 2016 Bailey s Motor 1879 Commutating sequence (partial): Ferrasis s first 4 motors 1885 and 1886 All two phase The last one has a magnetic core
18 U of I Seminar Page 18 TAK 9 / 16 / 2016 Force Mechanism Flux created by MMF Refer to Direct Current Machines by Michael Liwschitz (Second Edition 1956) Chapter 14 Tangential Forces in Electric Machines for a detailed presentation of force theory.
19 U of I Seminar Page 19 TAK 9 / 16 / 2016 Logic, Slip and the Equivalent Circuit The MMF and flux wave of an induction motor travel the same way that they do in a synchronous machine thus: RPM (synchronous) = 120 x Frequency / poles If the rotor of an induction motor travel exactly in step with the statorcreated field, then the flux looks to be at stand still when viewed from the rotor. If this is the case then no voltage / current can be induced in the rotor and it can produce no torque to keep itself spinning in lock step with the field wave. Induction motors never operate at synchronous speed under their own power. When motoring, induction motor run below synchronous speed or are slipping relative to synchronous speed. Slip ( S ) = (synchronous speed actual speed) synchronous speed
20 U of I Seminar Page 20 TAK 9 / 16 / 2016 At synchronous speed slip = 0 or 0% At stall / locked rotor slip = 1.0 or 100% Example: a 4 pole 60 hertz motor runs at 1740 RPM RPM synchronous = 120 x 60 / 4 = 1800 RPM Slip = ( ) / 1800 = 60 / 1800 =.033 = 3.3% Rotor electrical frequency = slip x stator frequency At synchronous speed Slip = 0, rotor frequency = 0, (No frequency, no induction) At stall slip =1, rotor frequency = line frequency For our example above rotor frequency =.033 x 60 hz = 2 hertz Rotors can be made of lower grade steel since operating frequency is low (and losses are low). It easy to observe that as load is increased in an induction motor that it slows down a bit just like DC motors. The induction motor equivalent circuit is a combination of the transformer equivalent circuit and the idea of slip. It was developed by Steinmetz. Prior to the equivalent circuit, motor performance was calculated using the circle diagram.
21 U of I Seminar Page 21 TAK 9 / 16 / 2016 Remember that the induction motor was described as being like a clutch?
22 U of I Seminar Page 22 TAK 9 / 16 / 2016 Is Ir or I2 Im The equivalent circuit as a tool No Load S 0 (near synchronous speed) R2 /S Rotor (secondary) nearly open circuited Almost no induced voltage Locked rotor (stall / standstill) S= 1 R2 / S = R2 Xm and Rc >> other parameters so they can be ignored Starting torque ~ I^2 x R2
23 U of I Seminar Page 23 TAK 9 / 16 / 2016 Plot of Equivalent circuit performance
24 U of I Seminar Page 24 TAK 9 / 16 / 2016 The derivation of the equivalent circuit is quite complex but the result is quite simple. All inductive parameters are treated with stator / line frequency though X2 physically experiences variable frequency. R2 is subject to skin effect and deep bar effect as slip increases. As a result R2 is greater at stall than running thereby increasing motor torque. (R2start > 1.5 x R2run). X2 is subject to saturation of the slot leakage due to frequency and high current at stall. As a result X2 is lower at stall than running. This increased locked current and thereby increases torque. (X2start < 1.5x X2run). With these effects varying with slip, the calculated motor performance looks more like actual performance of the motor as follows:
25 U of I Seminar Page 25 TAK 9 / 16 / 2016 FLT (full load torque) FLA (full load amps) BDT Locked PF LRT LRA With this enhance modeling: Locked current ( LRA) increases from 69 amps to 92 amps ( X1 + X2 reduced to 75% ) Locked torque (LRT) increase from 21 to 79 in # ( R2 increased to 210% of running value) Locked power factor increase from 19% to 38% Breakdown torque ( BDT) increases from 97 to 111 in # Some motors exhibit a belly in the torque curve called pull up torque (PUT). It s hard to predict or model.
26 U of I Seminar Page 26 TAK 9 / 16 / 2016 Running performance / Load saturation
27 U of I Seminar Page 27 TAK 9 / 16 / Motor Design and Application: The equivalent circuit, magnetics, and D^2xL The previous discussion of the equivalent circuit suggest that motor performance boils down to designing something that has the equivalent circuit parameters that will provide performance desired. How is this tied to magnetics and size or volume of the motor? What about thermal capability? The key parameter in motor performance / capability are X1, X2 and R2. All three are controlled by slot dimension, the number of turns (squared), and the size of the coil. (Slot permeance is a detailed subject of its own.) The parameter Xm, R1 are secondary parameters whose effects we wish to minimize. Ideally we want Xm to be infinite (to improve power factor) and R1 to be zero. Both of these parameters are strongly influenced by the size of the machine and the number of turns in the coils / winding. R1 and Rc in large part determine the machine losses and have no positive effect. R2 controls rotor loss but is special in that it controls locked torque and the slope of the torque curve in the running section. When flux loading of a machine is higher it can have less turns in the primary, having the big effect of reducing the equivalent circuit parameters and increasing machine capability. On the
28 U of I Seminar Page 28 TAK 9 / 16 / 2016 down side increasing flux loading decreases Xm and Rc increasing magnetic losses. (N= turns per phase) Φ= total flux per pole in lines The idea of D^2xL relates torque capability of a machine to volume measured at the air gap. Sizing constants (torque per air gap volume) consider magnetics, losses, heating and experience.
29 U of I Seminar Page 29 TAK 9 / 16 / 2016 No load saturation Xm, and Rc If the rotor or secondary current is 38 amps at unity power factor then: I = (21^2+38^2) = 43.4 amps PF = 38 / 43.4 =.876
30 U of I Seminar Page 30 TAK 9 / 16 / 2016 Is low rotor resistance a good thing? Consider if the rotor of the RJ motor was copper instead of aluminum. Customer says I want a motor with high efficiency a copper rotor but it needs to have good starting performance and a decent power factor when starting.??#??+
31 U of I Seminar Page 31 TAK 9 / 16 / 2016 Shaping the speed / torque curve
32 U of I Seminar Page 32 TAK 9 / 16 / 2016 How does voltage affect the motor? Torque profile proportional to V^2 ( 85 / 111.5)^2 =.58 Current proportional to V (85 / 111.5) =.76 Power factor unchanged Motor slows down torque margin eroded. How about at load conditions? Speed will reduce with lower voltage Simple load model Depends on load type (constant HP, constant torque, cube law) Current and PF depend on load change and dominance of magnetizing versus working current.
33 U of I Seminar Page 33 TAK 9 / 16 / 2016 How does frequency affect the motor? Torque inversely proportional to (frequency)^2 T@ 650 hz = (400/650)^2 of 400 hz = 38% Current inversely proportional to frequency 650 hz = (400/650) of 400 hz = 62% For both V and F T ~ ( V / F)^2 I (starting) ~ (V / F) V / F = flux, magnetic loading / strength At low frequency R1 and R2 become more dominant and erode torque and current.
34 U of I Seminar Page 34 TAK 9 / 16 / 2016 Constant V over F operation Torque fade at locked rotor
35 U of I Seminar Page 35 TAK 9 / 16 / 2016 Wound rotor and high resistance rotors Typical applications: Speed Control ( historic, inefficient) Punch presses, crushers, grinders Amusement park rides
36 U of I Seminar Page 36 TAK 9 / 16 / 2016 Brine resistors for rotor circuits can be 100 gallons or more!
37 U of I Seminar Page 37 TAK 9 / 16 / Motoring, Generating, and Braking / Plugging So far we have talked about operation between standstill and synchronous speed (1 to 0 slip). But what about speeds above synchronous speed or if the motor is turning backwards (wind milling) when it is started? The model is equally valid for these situations: Above synchronous speed the motor is in the generating regime. Slip is negative and the power of R2 becomes negative. At negative speed slip is greater than 1 and the rotor resistance and torque is less than that at stand still. R2 / S < R2 if S > 1 Induction generators must be connected to voltage for excitation. Vehicle induction motor drives braking (AC traction locomotives and road vehicles). Windmills with low frequency power fed into the wound rotor. Small hillside hydropower units.
38 U of I Seminar Page 38 TAK 9 / 16 / 2016
39 U of I Seminar Page 39 TAK 9 / 16 / Specifications NEMA and Aircraft NEMA National Electrical Manufacturers Association NEMA MG 1 specifies many of the details of commercially available motor (AC / DC, induction, synchronous, etc.). Induction motors are the biggest impact area. Key specification areas include: Lead / terminal marking requirements dual voltage, starting modes, direction of rotation, and field winding for DC motor. Frame dimensions motor frame sizes are describe by NEMA. 48 frame, 56 frame, 184TD, 324U.. C flange, D flange Integral frame induction motor certain horsepower and speed combinations are assigned to specific frame sizes. Induction motor types type B torque curve. Type D etc. Type B is standard BDT = 200%, LRT = 130%, PUT = 100% for a 25 HP motor. Locked rotor Code locked KVA per horsepower. Code G = 5.6 to 6.3 locked KVA per HP Code F = 5 to 5.6 locked KVA / HP Temperature rise requirements for different classes of insulation Enclosure requirements open drip proof, TEFC ( totally enclose fan cooled), TENV ( totally enclosed non ventilated) Efficiency standards big area today, high efficiency, premium efficiency.
40 U of I Seminar Page 40 TAK 9 / 16 / 2016 Aircraft Electrical Specifications: Standards: MIL STD 704 Aircraft Electrical Power Characteristic MIL STD M 7969 General Specification for Aircraft Alternating Current Motors, 400 Cycle 115 / 200 Volt System RTCA DO 160 Environmental Conditions and Test Procedures for Airborne Equipment Systems: 115 / 200 VAC (most commercial aircraft) 230 / 400 VAC ( Airbus A350 and Boeing 787) 28 VDC ( 24 volt battery) 270 VDC ( 1.35 x 200 VLL) CF (constant frequency) 400 hertz ( constant speed drive) NF (narrow frequency) 360 to 650 hertz ( tied to engine speed) WF (wide / wild frequency) 360 to 800 hertz Key Terms: POR point of regulation UET utilization equipment terminals Normal / Abnormal / Emergency Voltage and Frequency Essential Bus / Non Essential Bus RAT Ram Air Turbine PMP Pump Motor package ACMP / DCMP ( AC or DC motor pump)
41 U of I Seminar Page 41 TAK 9 / 16 / 2016 Key ACMP Attributes and Requirements Rotary Piston Pumps Regulated via hanger angle and hydraulic control system Regulation curve to work in parallel with other pumps Max electrical load defined in amps Maximum weight specifications Temperature 65F to 225 F Altitudes to 51,000 ft. Explosion proofness
Electrical Machines -II
Objective Type Questions: 1. Basically induction machine was invented by (a) Thomas Alva Edison (b) Fleming (c) Nikola Tesla (d) Michel Faraday Electrical Machines -II 2. What will be the amplitude and
More informationElectrical Machines II. Week 5-6: Induction Motor Construction, theory of operation, rotating magnetic field and equivalent circuit
Electrical Machines II Week 5-6: Induction Motor Construction, theory of operation, rotating magnetic field and equivalent circuit Asynchronous (Induction) Motor: industrial construction Two types of induction
More informationSynchronous Generators I. Spring 2013
Synchronous Generators I Spring 2013 Construction of synchronous machines In a synchronous generator, a DC current is applied to the rotor winding producing a rotor magnetic field. The rotor is then turned
More informationPretest Module 21 Units 1-4 AC Generators & Three-Phase Motors
Pretest Module 21 Units 1-4 AC Generators & Three-Phase Motors 1. What are the two main parts of a three-phase motor? Stator and Rotor 2. Which part of a three-phase squirrel-cage induction motor is a
More informationSynchronous Generators I. EE 340 Spring 2011
Synchronous Generators I EE 340 Spring 2011 Construction of synchronous machines In a synchronous generator, a DC current is applied to the rotor winding producing a rotor magnetic field. The rotor is
More informationFachpraktikum Elektrische Maschinen. Theory of Induction Machines
Fachpraktikum Elektrische Maschinen Theory of Induction Machines Prepared by Arda Tüysüz January 2013 Fundamentals Induction machines (also known as asynchronous machines) are by far the most common type
More informationROTATING MAGNETIC FIELD
Chapter 5 ROTATING MAGNETIC FIELD 1 A rotating magnetic field is the key to the operation of AC motors. The magnetic field of the stator is made to rotate electrically around and around in a circle. Stator
More informationESO 210 Introduction to Electrical Engineering
ESO 210 Introduction to Electrical Engineering Lectures-37 Polyphase (3-phase) Induction Motor 2 Determination of Induction Machine Parameters Three tests are needed to determine the parameters in an induction
More informationEEE3441 Electrical Machines Department of Electrical Engineering. Lecture. Introduction to Electrical Machines
Department of Electrical Engineering Lecture Introduction to Electrical Machines 1 In this Lecture Induction motors and synchronous machines are introduced Production of rotating magnetic field Three-phase
More information2014 ELECTRICAL TECHNOLOGY
SET - 1 II B. Tech I Semester Regular Examinations, March 2014 ELECTRICAL TECHNOLOGY (Com. to ECE, EIE, BME) Time: 3 hours Max. Marks: 75 Answer any FIVE Questions All Questions carry Equal Marks ~~~~~~~~~~~~~~~~~~~~~~~~~~
More informationAC MOTOR TYPES. DESCRIBE how torque is produced in a single-phase AC motor. EXPLAIN why an AC synchronous motor does not have starting torque.
Various types of AC motors are used for specific applications. By matching the type of motor to the appropriate application, increased equipment performance can be obtained. EO 1.5 EO 1.6 EO 1.7 EO 1.8
More informationECE 325 Electric Energy System Components 6 Three Phase Induction Motors. Instructor: Kai Sun Fall 2016
ECE 325 Electric Energy System Components 6 Three Phase Induction Motors Instructor: Kai Sun Fall 2016 1 Content (Materials are from Chapters 13-15) Components and basic principles Selection and application
More informationDEPARTMENT OF EI ELECTRICAL MACHINE ASSIGNMENT 1
It is the mark of an educated mind to be able to entertain a thought without accepting it. DEPARTMENT OF EI ELECTRICAL MACHINE ASSIGNMENT 1 1. Explain the Basic concepts of rotating machine. 2. With help
More informationSingle Phase Induction Motor. Dr. Sanjay Jain Department Of EE/EX
Single Phase Induction Motor Dr. Sanjay Jain Department Of EE/EX Application :- The single-phase induction machine is the most frequently used motor for refrigerators, washing machines, clocks, drills,
More informationDEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING QUESTION BANK 16EET41 SYNCHRONOUS AND INDUCTION MACHINES UNIT I SYNCHRONOUS GENERATOR 1. Why the stator core is laminated? 2. Define voltage regulation
More informationCódigo de rotor bloqueado Rotor bloqueado, Letra de código. Rotor bloqueado, Letra de código
Letra de código Código de rotor bloqueado Rotor bloqueado, Letra de código kva / hp kva / hp A 0.00 3.15 L 9.00 10.00 B 3.15 3.55 M 10.00 11.00 C 3.55 4.00 N 11.00 12.50 D 4.00 4.50 P 12.50 14.00 E 4.50
More informationCHAPTER 6 DESIGN AND DEVELOPMENT OF DOUBLE WINDING INDUCTION GENERATOR
100 CHAPTER 6 DESIGN AND DEVELOPMENT OF DOUBLE WINDING INDUCTION GENERATOR 6.1 INTRODUCTION Conventional energy resources are not sufficient to meet the increasing electrical power demand. The usages of
More information(d) None of the above.
Dr. Mahalingam College of Engineering and Technology, Pollachi-3 (An Autonomous Institution affiliated to Anna niversity) CCET II (2016 Regulation) Name of Programme: B.E. (EEE) Course Code & Course Title:
More informationThe Wound-Rotor Induction Motor Part I
Experiment 1 The Wound-Rotor Induction Motor Part I OBJECTIVE To examine the construction of the three-phase wound-rotor induction motor. To understand exciting current, synchronous speed and slip in a
More informationChapter 3.2: Electric Motors
Part I: Objective type questions and answers Chapter 3.2: Electric Motors 1. The synchronous speed of a motor with 6 poles and operating at 50 Hz frequency is. a) 1500 b) 1000 c) 3000 d) 750 2. The efficiency
More information14 Single- Phase A.C. Motors I
Lectures 14-15, Page 1 14 Single- Phase A.C. Motors I There exists a very large market for single-phase, fractional horsepower motors (up to about 1 kw) particularly for domestic use. Like many large volume
More informationCHAPTER THREE DC MOTOR OVERVIEW AND MATHEMATICAL MODEL
CHAPTER THREE DC MOTOR OVERVIEW AND MATHEMATICAL MODEL 3.1 Introduction Almost every mechanical movement that we see around us is accomplished by an electric motor. Electric machines are a means of converting
More informationSIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR
SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR Siddharth Nagar, Narayanavanam Road 517583 QUESTION BANK (DESCRIPTIVE) Subject with Code : ET(16EE212) Year & Sem: II-B.Tech & II-Sem UNIT I DC GENERATORS Course
More informationINDUCTION MOTOR. There is no physical electrical connection to the secondary winding, its current is induced
INDUCTION MOTOR INTRODUCTION An induction motor is an alternating current motor in which the primary winding on one member (usually the stator) is connected to the power source and a secondary winding
More informationLab Electrical Power Engineering I
INSTITUT FÜR ELEKTRISCHE MASCHINEN RHEINISCH-WESTFÄLISCHE TECHNISCHE HOCHSCHULE AACHEN Lab Electrical Power Engineering I Test 3: Induction machine with squirrel cage rotor and slip ring rotor 1 Experiment
More informationInduction Motor Control
Induction Motor Control A much misunderstood yet vitally important facet of electrical engineering. The Induction Motor A very major consumer of electrical energy in industry today. The major source of
More informationAPGENCO/APTRANSCO Assistant Engineer Electrical Previous Question Papers Q.1 The two windings of a transformer is conductively linked. inductively linked. not linked at all. electrically linked. Q.2 A
More informationVIII. Three-phase Induction Machines (Asynchronous Machines) Induction Machines
VIII. Three-phase Induction Machines (Asynchronous Machines) Induction Machines 1 Introduction Three-phase induction motors are the most common and frequently encountered machines in industry simple design,
More informationRegulation: R16 Course & Branch: B.Tech EEE
SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR Siddharth Nagar, Narayanavanam Road 517583 QUESTION BANK (Descriptive) Subject with Code : Electrical Machines-II (16EE215) Regulation: R16 Course & Branch: B.Tech
More informationDate: Name: ID: LABORATORY EXPERIMENT NO. 8 INDUCTION MOTOR/GENERATOR 8-1
Date: Name: ID: LABORATORY EXPERIMENT NO. 8 INDUCTION MOTOR/GENERATOR 8-1 OBJECT 1. To determine the general performance of a squirrel motors 2. To observe the characteristics of induction generators.
More informationDoubly fed electric machine
Doubly fed electric machine Doubly fed electric machines are electric motors or electric generators that have windings on both stationary and rotating parts, where both windings transfer significant power
More informationElectrical Machines-I (EE-241) For S.E (EE)
PRACTICAL WORK BOOK For Academic Session 2013 Electrical Machines-I (EE-241) For S.E (EE) Name: Roll Number: Class: Batch: Department : Semester/Term: NED University of Engineer ing & Technology Electrical
More informationCHAPTER 3 DESIGN OF THE LIMITED ANGLE BRUSHLESS TORQUE MOTOR
33 CHAPTER 3 DESIGN OF THE LIMITED ANGLE BRUSHLESS TORQUE MOTOR 3.1 INTRODUCTION This chapter presents the design of frameless Limited Angle Brushless Torque motor. The armature is wound with toroidal
More informationChapter 17 Notes. Magnetism is created by moving charges.
Chapter 17 Notes Section 17.1 Electric Current and Magnetism Hans Christian Øersted (1819), a Danish physicist and chemist - compass needle near a wire circuit and with current flowing through the wire,
More informationPart- A Objective Questions (10X1=10 Marks)
Dr. Mahalingam College of Engineering and Technology, Pollachi-3 (An Autonomous Institution) CCET 3(2016Regulation) Name of Programme: B.E. (EEE) Course Code&Course Title: 16EET41 & Synchronous & Induction
More informationInduction machine characteristics and operation. Induction Machines
Induction Machines 1.1 Introduction: An essential feature of the operation of the synchronous machine is that the rotor runs at the same speed as the rotating magnetic field produced by the stator winding.
More informationMotor Protection Fundamentals. Motor Protection - Agenda
Motor Protection Fundamentals IEEE SF Power and Energy Society May 29, 2015 Ali Kazemi, PE Regional Technical Manager Schweitzer Engineering Laboratories Irvine, CA Copyright SEL 2015 Motor Protection
More informationChapter 4 DC Machines
Principles of Electric Machines and Power Electronics Chapter 4 DC Machines Third Edition P. C. Sen Chapter 4 DC machine Electric machine Type: rotating machine Applications: generator (electric source)
More informationRenewable Energy Systems 13
Renewable Energy Systems 13 Buchla, Kissell, Floyd Chapter Outline Generators 13 Buchla, Kissell, Floyd 13-1 MAGNETISM AND ELECTROMAGNETISM 13-2 DC GENERATORS 13-3 AC SYNCHRONOUS GENERATORS 13-4 AC INDUCTION
More informationPretest Module 21 Units 1-3 AC Generators & Three-Phase Motors
Pretest Module 21 Units 1-3 AC Generators & Three-Phase Motors 1. What are the two main parts of a three-phase 2. Which part of a three-phase squirrel-cage induction motor is a hollow core? 3. What are
More informationHistorical Development
TOPIC 3 DC MACHINES DC Machines 2 Historical Development Direct current (DC) motor is one of the first machines devised to convert electrical power into mechanical power. Its origin can be traced to the
More informationBELT-DRIVEN ALTERNATORS
CHAPTER 13 BELT-DRIVEN ALTERNATORS INTRODUCTION A generator is a machine that converts mechanical energy into electrical energy using the principle of magnetic induction. This principle is based on the
More informationINSTITUTE OF AERONAUTICAL ENGINEERING Dundigal, Hyderabad
INSTITUTE OF AERONAUTICAL ENGINEERING Dundigal, Hyderabad - 500 043 MECHANICAL ENGINEERING ASSIGNMENT Name : Electrical and Electronics Engineering Code : A40203 Class : II B. Tech I Semester Branch :
More information9/7/2010. Chapter , The McGraw-Hill Companies, Inc. MOTOR CLASSIFICATION. 2010, The McGraw-Hill Companies, Inc.
Chapter 2 MOTOR CLASSIFICATION 1 In general, motors are classified according to the type of power used (AC or DC) and the motor's principle of operation. AC DC Motor Family Tree 2 DC MOTOR CONNECTIONS
More informationIT 318 SUPPLEMENTARY MATERIAL CHAPTER 4
IT 318 SUPPLEMENTARY MATERIAL CHAPTER 4 Electric Motors V. 2013 BARRY M. LUNT Brigham Young University Table of Contents Chapter 4: Electric Motors... 2 Overview... 2 4-1 Commutation... 2 4-2 Stepper Motors...
More informationSIMULINK Based Model for Determination of Different Design Parameters of a Three Phase Delta Connected Squirrel Cage Induction Motor
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) e-issn: 2278-1676,p-ISSN: 2320-3331, Volume 7, Issue 4 (Sep. - Oct. 2013), PP 25-32 SIMULINK Based Model for Determination of Different
More informationInstructor. Payam Zarbakhsh. Department of electrical electronics engineering
Instructor Payam Zarbakhsh Department of electrical electronics engineering Electrical Machines Induction Motors_Note(1) Comparing with synchronous motor No dc field current is required to run the machine.
More informationCSDA Best Practice. Hi-Cycle Concrete Cutting Equipment. Effective Date: Oct 1, 2010 Revised Date:
CSDA Best Practice Title: Hi-Cycle Concrete Cutting Equipment Issue No: CSDA-BP-010 : Oct 1, 2010 Revised : Introduction Hi-cycle/high frequency concrete cutting equipment has become more prevalent in
More informationJust what is an alternator?
Just what is an alternator? An alternator is the device used to produce the electricity the car needs to run and to keep the battery charged. The battery is the heart of your electrical system. But you
More informationSingle Phase Induction Motors
Single Phase Induction Motors Prof. T. H. Panchal Asst. Professor Department of Electrical Engineering Institute of Technology Nirma University, Ahmedabad Introduction As the name suggests, these motors
More informationMost home and business appliances operate on single-phase AC power. For this reason, singlephase AC motors are in widespread use.
Chapter 5 Most home and business appliances operate on single-phase AC power. For this reason, singlephase AC motors are in widespread use. A single-phase induction motor is larger in size, for the same
More informationDC CIRCUITS ELECTROMAGNETISM
DC CIRCUITS 1. State and Explain Ohm s Law. Write in brief about the limitations of Ohm s Law. 2. State and explain Kirchhoff s laws. 3. Write in brief about disadvantages of series circuit and advantages
More informationAE105 PRINCIPLES OF ELECTRICAL ENGINEERING JUNE 2014
Q.2 a. Explain in detail eddy current losses in a magnetic material. Explain the factors on which it depends. How it can be reduced? IETE 1 b. A magnetic circuit with a single air gap is shown in given
More informationMotor Basics AGSM 325 Motors vs Engines
Motor Basics AGSM 325 Motors vs Engines Motors convert electrical energy to mechanical energy. Engines convert chemical energy to mechanical energy. 1 Motors Advantages Low Initial Cost - $/Hp Simple &
More informationCHAPTER 7 INDUCTION MOTOR
CHAPTE 7 INDUCTION MOTO Summary: 1. Induction Motor Construction. Basic Induction Motor Concepts - The Development of Induced Torque in an Induction Motor. - The Concept of otor Slip. - The Electrical
More informationIntroduction: Electromagnetism:
This model of both an AC and DC electric motor is easy to assemble and disassemble. The model can also be used to demonstrate both permanent and electromagnetic motors. Everything comes packed in its own
More informationRevised October 6, EEL 3211 ( 2008, H. Zmuda) 6. Induction Motors 1
Induction Motors Revised October 6, 008 EEL 311 ( 008, H. Zmuda) 6. Induction Motors 1 Induction Motors: We just learned how damper or amortisseur windings on a synchronous motor could develop a starting
More informationINTRODUCTION Principle
DC Generators INTRODUCTION A generator is a machine that converts mechanical energy into electrical energy by using the principle of magnetic induction. Principle Whenever a conductor is moved within a
More informationDev Bhoomi Institute Of Technology LABORATORY Department of Electrical And Electronics Engg. Electro-mechanical Energy Conversion II
REV. NO. : REV. DATE : PAGE: 1 Electro-mechanical Energy Conversion II 1. To perform no load and blocked rotor tests on a three phase squirrel cage induction motor and determine equivalent circuit. 2.
More informationSYLLABUS 1. SYNCHRONOUS GENERATOR 9 2. SYNCHRONOUS MOTOR 8
SYLLABUS 1. SYNCHRONOUS GENERATOR 9 Constructional details Types of rotors emf equation Synchronous reactance Armature reaction Voltage regulation EMF, MMF, ZPF and A.S.A methods Synchronizing and parallel
More information10. Starting Method for Induction Motors
10. Starting Method for Induction Motors A 3-phase induction motor is theoretically self starting. The stator of an induction motor consists of 3-phase windings, which when connected to a 3-phase supply
More informationAGN Unbalanced Loads
Application Guidance Notes: Technical Information from Cummins Generator Technologies AGN 017 - Unbalanced Loads There will inevitably be some applications where a Generating Set is supplying power to
More information34 th Hands-On Relay School
34 th Hands-On Relay School Generation Track Overview Lecture Generator Design, Connections, and Grounding 1 Generator Main Components Stator Core lamination Winding Rotor Shaft Poles Slip rings Stator
More informationCHAPTER 6 INTRODUCTION TO MOTORS AND GENERATORS
CHAPTER 6 INTRODUCTION TO MOTORS AND GENERATORS Objective Describe the necessary conditions for motor and generator operation. Calculate the force on a conductor carrying current in the presence of the
More informationScope for Electrical Machine Design. Objectives. Design and Engineering. Course Description. 23-Dec-16 DESIGN OF ELECTRICAL MACHINES AN OVERVIEW
SNS COLLEGE OF ENGINEERING (Accredited by NAAC-UGC with A Grade, Approved by AICTE, Recognized by UGC and Affiliated to Anna University, Chennai) COIMBATORE 641 107 DEPARTMENT OF ELECTRICAL AND ELECTRONICS
More informationProducts & Services EQ Series AC Drives. TEAMMaster WOUND ROTOR MOTORS WORLD SERIES SYNCHRONOUS MOTORS. EXPLOSION PROOF (Division 1, Zone 1)
630-543-7867 Products & Services EQ7 1-1000 hp Intelligent Keypad with Extensive Diagnostics Select Any of 4 Control Methods - V/ Hz - Dynamic Torque - Sensorless Vector - Closed-loop Vector Quick Setup
More informationTable of Contents Lesson One Lesson Two Lesson Three Lesson Four Lesson Five Lesson Six Lesson Seven Lesson Eight Lesson Nine Lesson Ten
Table of Contents Lesson One Lesson Two Lesson Three Introduction to Single-Phase Motors...3 Split-Phase Motors...21 Capacitor Motors...37 Lesson Four Lesson Five Lesson Six Repulsion Motors...55 Universal
More information9. Examples of hydro energy conversion
9. Examples of hydro energy conversion VATech Hydro, Austria Prof. A. Binder 9/1 Variable speed pump storage power plant Prof. A. Binder 9/2 Conventional pump storage power plant with synchronous motor-generators
More informationVALLIAMMAI ENGINEERING COLLEGE
VALLIAMMAI ENGINEERING COLLEGE SRM Nagar, Kattankulathur 603 203. DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING Question Bank EE6401 ELECTRICAL MACHINES I UNIT I: MAGNETIC CIRCUITS AND MAGNETIC
More informationR13 SET - 1. b) Describe different braking methods employed for electrical motors. [8M]
Code No:RT32026 R13 SET - 1 III B. Tech II Semester Regular Examinations, April - 2016 POWER SEMICONDUCTOR DRIVES (Electrical and Electronics Engineering) Time: 3 hours Maximum Marks: 70 Note: 1. Question
More informationChapter 7: DC Motors and Transmissions. 7.1: Basic Definitions and Concepts
Chapter 7: DC Motors and Transmissions Electric motors are one of the most common types of actuators found in robotics. Using them effectively will allow your robot to take action based on the direction
More informationDHANALAKSHMI COLLEGE OF ENGINEERING MANIMANGALAM. TAMBARAM, CHENNAI B.E. ELECTRICAL AND ELECTRONICS ENGINEERING
DHANALAKSHMI COLLEGE OF ENGINEERING MANIMANGALAM. TAMBARAM, CHENNAI B.E. ELECTRICAL AND ELECTRONICS ENGINEERING V SEMESTER EE2305 ELECTRICAL MACHINES II LABORATORY LABORATORY MANUAL 1 CONTENT S. No. Name
More informationBasic Motor Theory. Introduction
Basic Motor Theory Introduction It has been said that if the Ancient Romans, with their advanced civilization and knowledge of the sciences, had been able to develop a steam motor, the course of history
More informationAUCOM WHITE PAPER SERIES GET YOUR MOTOR RUNNING. An introduction to reduced voltage starting of three phase induction motors
AUCOM WHITE PAPER SERIES GET YOUR MOTOR RUNNING An introduction to reduced voltage starting of three phase induction motors GET YOUR MOTOR RUNNING WHITE PAPER #1 Reduced voltage starting of three phase
More informationUNIT 2. INTRODUCTION TO DC GENERATOR (Part 1) OBJECTIVES. General Objective
DC GENERATOR (Part 1) E2063/ Unit 2/ 1 UNIT 2 INTRODUCTION TO DC GENERATOR (Part 1) OBJECTIVES General Objective : To apply the basic principle of DC generator, construction principle and types of DC generator.
More informationAsynchronous slip-ring motor synchronized with permanent magnets
ARCHIVES OF ELECTRICAL ENGINEERING VOL. 66(1), pp. 199-206 (2017) DOI 10.1515/aee-2017-0015 Asynchronous slip-ring motor synchronized with permanent magnets TADEUSZ GLINKA, JAKUB BERNATT Institute of Electrical
More informationSub:EE6604/DESIGN OF ELECTRICAL MACHINES Unit V SYNCHRONOUS MACHINES. 2. What are the two type of poles used in salient pole machines?
SRI VIDYA COLLEGE OF ENGINEERING & TECHNOLOGY DEPARTMENT OF EEEE QUESTION BANK Sub:EE6604/DESIGN OF ELECTRICAL MACHINES Unit V SYNCHRONOUS MACHINES 1. Name the two types of synchronous machines. 1. Salient
More informationElectrical Machines, Drives, and Power Systems Theodore Wildi Sixth Edition
Electrical Machines, Drives, and Power Systems Theodore Wildi Sixth Edition Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world Visit us
More informationUNIT I SYNCHRONOUS GENERATOR PART-A
1. What is an alternator? UNIT I SYNCHRONOUS GENERATOR PART-A An alternator or AC generator is a synchronous machine which converts mechanical energy into electrical energy and produces alternating emf.
More informationUnit III-Three Phase Induction Motor:
INTRODUCTION Unit III-Three Phase Induction Motor: The three phase induction motor runs on three phase AC supply. It is an ac motor. The power is transferred by means of induction. So it is also called
More informationPRIMELINE. Induction Generator. Now Introducing Single Bearing Designs. Simple, Reliable Power For Wind or Engine Driven Applications
PRIMELINE Induction Generator Now Introducing Single Bearing Designs Simple, Reliable Power For Wind or Engine Driven Applications ISO 9001: 2000 Certified PRIMELINE Induction Generator General Description
More informationStarting of Induction Motors
1- Star Delta Starter The method achieved low starting current by first connecting the stator winding in star configuration, and then after the motor reaches a certain speed, throw switch changes the winding
More informationVariable Frequency Drive Basics
Variable Frequency Drive Basics Contact us Today for a FREE quotation to deliver this course at your company?s location. https://www.electricityforum.com/onsite-training-rfq Variable Frequency Drives are
More information2 Principles of d.c. machines
2 Principles of d.c. machines D.C. machines are the electro mechanical energy converters which work from a d.c. source and generate mechanical power or convert mechanical power into a d.c. power. These
More informationFundamentals of Motors
Fundamentals of Motors 5/05 FOM Fundamentals of Motors Table of Contents Electrical and Magnetic Basics................................................................ 1-2 Fluid Flow versus Electron Flow.............................................................
More informationPI Electrical Equipment - Course PI 30.2 MOTORS
Electrical Equipment - Course PI 30.2 MOTORS OBJECTIVES On completion of this module the student will be able to: 1. Briefly explain, in writing, "shaft rotation" as an interaction of stator and rotor
More informationR07 SET - 1
R07 SET - 1 II B. Tech II Semester Supplementary Examinations April/May 2013 ELECTRICAL MACHINES - II (Electrical and Electronics Engineering) Time: 3 hours Max. Marks: 80 Answer any FIVE Questions All
More informationThree-Phase Induction 208V Motor with MATLAB
EXPERIMENT Induction motor with Matlab Three-Phase Induction Motors 208V LL OBJECTIVE This experiment demonstrates the performance of squirrel-cage induction motors and the method for deriving electrical
More informationDesign of Brushless Permanent-Magnet Machines. J.R. Hendershot Jr. T.J.E. Miller
Design of Brushless Permanent-Magnet Machines J.R. Hendershot Jr. T.J.E. Miller Contents 1 GENERAL INTRODUCTION l 1.1 Definitions and types of brushless motor 1 1.2 Commutation,. 4 1.3 Operation of 3-phase
More informationSt.MARTIN S ENGINEERING COLLEGE Dhulapally, Secunderabad
St.MARTIN S ENGINEERING COLLEGE Dhulapally, Secunderabad-500 014 Subject: STATIC DRIVES Class : EEE III TUTORIAL QUESTION BANK Group I QUESTION BANK ON SHORT ANSWER QUESTION UNIT-I 1 What is meant by electrical
More information"Motors, Power, and Data Loggers Greg Jourdan-Wenatchee Valley College Carol Lewellen-NEEC and BOC Tuesday, May 8, Sessions Session
"Motors, Power, and Data Loggers Greg Jourdan-Wenatchee Valley College Carol Lewellen-EEC and BOC Tuesday, May 8, 2018 3 Sessions Session 1-8:30-9:25 a.m. Motors 101 Session 2-9:30-10:25 a.m. - Power Session
More informationElectrical Theory. Generator Theory. PJM State & Member Training Dept. PJM /22/2018
Electrical Theory Generator Theory PJM State & Member Training Dept. PJM 2018 Objectives The student will be able to: Describe the process of electromagnetic induction Identify the major components of
More informationLecture 20: Stator Control - Stator Voltage and Frequency Control
Lecture 20: Stator Control - Stator Voltage and Frequency Control Speed Control from Stator Side 1. V / f control or frequency control - Whenever three phase supply is given to three phase induction motor
More informationELEN 236 DC Motors 1 DC Motors
ELEN 236 DC Motors 1 DC Motors Pictures source: http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/mothow.html#c1 1 2 3 Some DC Motor Terms: 1. rotor: The movable part of the DC motor 2. armature: The
More informationSQA Advanced Unit specification: general information
SQA Advanced Unit specification: general information Unit title: Electrical Machine Principles Unit code: HT83 47 Superclass: XJ Publication date: August 2017 Source: Scottish Qualifications Authority
More informationSECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS UNIT OBJECTIVES UNIT OBJECTIVES 3/21/2012
SECTION 4 ELECTRIC MOTORS UNIT 17: TYPES OF ELECTRIC MOTORS UNIT OBJECTIVES After studying this unit, the reader should be able to Describe the different types of open single-phase motors used to drive
More informationGROUP OF INSTITUTIONS :: PUTTUR UNIT I SINGLE PHASE TRANSFORMERS
SIDDHARTH GROUP OF INSTITUTIONS :: PUTTUR Siddharth Nagar, Narayanavanam Road 517583 QUESTION BANK (Descriptive) Subject with Code : Electrical Machines-II (16EE215) Course & Branch: B.Tech EEE Regulation:
More informationELECTRICAL MAINTENANCE
ELECTRICAL MAINTENANCE II PRACTICAL JOURNAL DATA 1 EXPERIMENT NO. 1 AIM: TO FIND VOLTAGE RATIO OF A GIVEN TRANSFORMER. CIRCUIT DIAGRAM: OBSERVATION TABLE: Sr.No. 1 2 3 4 Primary Voltage (V 1 ) Secondary
More informationDESIGN OF DC MACHINE
DESIGN OF DC MACHINE 1 OUTPUT EQUATION P a = power developed by armature in kw P = rating of machine in kw E = generated emf, volts; V = terminal voltage, volts p = number of poles; I a = armaure current,
More informationECET 211 Electric Machines & Controls Lecture 5-1 Electric Motors. Lecture 5-1 Electric Motors
ECET 211 Electric Machines & Controls Lecture 5-1 Electric Motors (2 of 4) Text Book: Chapter 5 Electric Motors, Electric Motors and Control Systems, by Frank D. Petruzella, published by McGraw Hill, 2015.
More information