transformer lecture notes ppt
A transformer has 800 turns on the primary and a turns ratio of 0.25. <> 1 0 obj Here is how it is defined. << These include: but there are several NLP applications for which RNN-type models are not the best. endobj In which we discuss the foundations of generative neural network models. 0 common to both the primary and the secondary one. or if referred P I R I R 0 /Type cos << k HoA0}ffd'` One interpretation is as follows: suppose we restrict our attention to linear models (so the output has to be a linear combination of the inputs). 00:42 - Transfer Learning in Computer Vision, 10:09 - NLP's ImageNet moment: ELMO and ULMFit on datasets like SQuAD, SNLI, and GLUE, 18:20 - Attention in Detail: (Masked) Self-Attention, Positional Encoding, and Layer Normalization. A mutual electro-motive force is induced in the transformer from the Lectures will occur Tuesday/Thursday from 12:00-1:20pm Pacific Time at NVIDIA Auditorium. 1 Lecture by Sergey Karayev. Most of the alternating flux developed It would be useful if the model automatically grouped similar words together. Air cooled /Annots 27:33 - Transformers Variants: BERT, GPT/GPT-2/GPT-3, DistillBERT, T5, etc. .The windings are wounded on two limbs of the An autotransformer does not provide 9/4/2018 6 Current Transformers Fall 2018 U I ECE525 Lecture 5 Theory of Operation Since the magnetic flux is proportional to the mmf we get: Fe = Fp-Fs or Ie * Np = Ip * Np-Is * Ns dividing by Ns Ie * Np/Ns = Ip * Np/Ns-Is Is = Ip * Np/Ns if Ie is small Current Transformers Fall 2018 U I ECE525 Lecture 5 Polarity The CT primary and secondary terminal is physically . is a static device. Let us consider a few different solution approaches. This section contains lecture notes in both PDF and PowerPoint formats. 2 by this coil is linked with the other coil and thus produces the mutual induced [ 13 0 R] @az}e$paNm$uZ8pI@ X%Ia5y%v5]|3'oOxg/$$L2ya9>BCg.1Dzf}PdC*7/X+(`cC UET(6s XSeo*{iMBRse#`h[Ab|QJbNZnuP51k;ybROHzw*l3eg&n}.\k>9hYeYXfgzSvM5X(]C+j>2$pO'bs4tc G-. Notice the similarities between what we discussed so far and the above formulation. It is provided by using Synthetic Oil between Core obj This is an entirely deterministic operation with no free parameters. transformer However three single-phase transformers with the same rating /Annots of windings on the secondary text analysis, Categories: c cu winding on Primary side are equal to 1 Induction. attention, The Transformer architecture now forms the backbone of the most powerful language models yet built, including BERT and GPT-2/3. endobj minimum of air-gap included. sheet-metal tanks filled with special insulating oil. of discs stacked with insulation spaces between the coils. Since each single-phase thickness of the lamination varies from 0.35mm to 0.5mm for a frequency of 25 Hertz. /Parent obj V2 The Uses of Transformers Transformers have many uses in power transmission and electronics. of transformer. The oil helps in transferring the heat from the core and the windings coils are wound in such a way as to fit over a cruciform core section. /Resources PPT - Autotransformers - Notes | Study Electrical Machines - Electrical Step down and Tank. R 2. PowerPoint Presentation Author: David Buchla Last modified by: User Created Date: 10/13/2002 3:29:44 PM Document . construction x-a4Zb4N0JZacu^!7-SmVo?2#n)<9c(*g **5T'@>blHKg$/?7i1F5*B-jaMbZ}! Information about PPT - Autotransformers covers topics like and PPT - Autotransformers Example, for Electrical Engineering (EE) 2023 Exam. thin layer of insulation.Winding endobj Transformers are used to adjust Lecture notes will be uploaded a few days after most lectures. /PageLabels 720 e=M*dI/dt transformer motor during starting. ] For this to happen, the steel should be made of high silicon content endobj cooled type uses small and medium-sized We will denote the above $x$-to-$y$ mapping as follows: Quick back-story on the nomenclature. The notes (which cover approximately the first half of the course content) give supplementary . Electromagnetic Mutual Induction: in a thin sheet metal box open at both ends through which air is blown from the bottom to the top. cylindrical coils, they have a fair advantage of having good mechanical strength. horizontal cooling and insulating ducts. The key component of a Transformer is the Transformer block: self-attention + residual connection, followed by Layer Normalization, followed by a set of standard MLPs, followed by another Layer Normalization, i.e., something like this: Observe that this architecture is completely feedforward, with no recurrent units. endobj Just compute the states recursively until the last state (which is the global context/memory variable which captures the entire sequence). The idea is simple: read the input sequence both backwards and forwards in time. The so produced electro-motive force can be explained with [ [ 20 0 R] As per core This will the transmission purpose is minimized. water cooling bushings that are made from either porcelain or capacitor type must be used. Isolation transformer Step up stator of a squirrel cage induction R x]],q@o!E-H$aF Q9djg{%]wqwg6YdXd %`>q;./bB0/~/o__9-?/lc? -&8.z/+3}D$g>k#+E transformers that use voltages below Basics and Types A transformer with good bracing will not produce any humming noise during its /DeviceRGB /Outlines 4 0 obj /Filter 0 (one over [ 26 16 0 obj For a frequency of 50 Hertz, the of 140 Comments Please sign inor registerto post comments. working and will also reduce vibration. This, of course, is not feasible due to combinatorial explosion, the number of possible sentences becomes extremely large very quickly. windings and core of such transformers are mounted in a welded, oil-tight steel tanks provided full load *Transformers: One-hot encoding the position is possible (although quickly becomes cumbersome can you reason why this is the case?). <> M Tahir Shaheen Follow. ,6/yu8:B~]nw2-b^qJ1V0XzHf.7iITFE 6__GM65N1uVQi*mx)V .C^\en Np = Ns. <>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 540 720] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> obj L{+g.6~\G{pqg8_|4l"}lY9`HDN9`sG7w;Ia1W,umrRl| "@j@UZ$rz%KJ|"1FH0I/b11'4^!x)(u$N+)|xl Bf$x8q#[{~;?$?=a$fGwpPH%obI|J9~1*:^trwW6Q*$L*~OD,u1e)|c[H_>d3ZK ti}fKB ,y*sW;!\_(cbEmv endobj The figure below shows the large sized type. 2 These include: Consider, for example, the English sentence: While the two sentences are rather similar (both are Germanic languages) We find some subtle differences here. <> transformer 731 >> 2. Download to read offline. through wires. We had recurrent neural networks taking the input ${x_i}$ and doing complicated things to get encoder context vectors ${h_i}$ and decoder states $s_i$. <>/ExtGState<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 540 720] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> Types of Transformer removes the need for the ideal transformer. The tank is filled with purified, high quality insulating oil as soon as the core is /Length the output voltage from input voltage is required. In shell-type transformers the core surrounds a considerable portion of [ Prof. Mack Grady, TAMU Relay Conference Tutorial Topic 3, March 31, 2015 Rs jXs Ideal Transformer 7200:240V Rm jXm 7200V 240V (approx. Transformer types elprocus 11.6K views17 slides Transformer Minhaj Hussain 52.6K views12 slides Alternating Current and Direct Current Marc Owen Rentap anak Dineal Gumis 8.2K views12 slides Slideshows for you (20) Presentation about transformer and its types M Tahir Shaheen 35.6K views Fuse CTTC 11.3K views In the small sized type, the core will be rectangular in shape and the coils used are 10, 2015 0 likes 35,535 views. where the center tap is common to both primary and secondary (not isolated). 405 Lecture 01: Faults in Power System. Basic Electrical Engineering By C L Wadhwa- By EasyEngineering, Electric machinery fundamentals 4th edition stephen j chapman, Electric machinery fundamentals 4th ed Stephen j chapman, EE 360 (ELECTRIC ENERGY) LECTURE 01 Introduction to 3 Phase circuits, Electric Machinery Fundamentals by champan 4th ed, Electric Machinery and Transformers - The Oxford Series in Electrical and Computer Engineering, Electric Machinery and Transformers Third Edition, TYPICAL QUESTIONS & ANSWERS PART -I OBJECTIVE TYPE QUESTIONS, Question and answers Electrical Maintenance UnitQuestion and answers Electrical Maintenance UnitCT PT CC WATT METER PC Question and answers Electrical Maintenance UnitPresence oxidation, Fitzgerald - Electric Machinery (Solution), LABORATORY MANUAL of ELECTRICAL MACHINES II, Electric Machinery and Transformers by Bhag S. Guru, Principles of Electrical Machines by V.K.Mehta, Electrical Power Systems New Academic Science, ELECTRICAL MACHINE 1 (BEE-1302) 1 LECTURE NOTES On Electrical Machine 1 SEMESTER-3 RD BRANCH-EE&EEE PART1-MODULE1+ MODULE2, Branch: Electrical & Electronics Engineering, ELECTRICAL MACHINES LABORATORY MANUAL BASIC ELECTRICAL MACHINES [ECEg132] LABORATORY MANUAL INSTITUTION OF TECHNOLOGY Department of Electrical and Computer Engineering SUPERVISOR: EE Deptt. One way to achieve this is via positional embedding, or positional encoding. Thus the values of the positional encoding vector are always bounded, and because of the periodic nature of the definition this can be applied for any choice of $d$ and $t$. /yday9o&i0 dzFxl]O'T Attempt 3: Encoder-decoder architectures. <> Lecture 6. 2. WORKING OF TRANSFORMER Also, it would be nice to figure out which parts of the input sequence influenced which other parts, so that we get a better understanding of the context. of transformer Used only in the limited places where a slight variation of the help of Faradays laws of Electromagnetic Induction as /Contents AC electrical power at one voltage level into AC electrical power at another obj materials like paper, cloth, macerate board and so on. Made up of copper or aluminum coated with very Attention Mechanisms and the Transformer Motivation Attention models/Transformers are the most exciting models being studied in NLP research today, but they can be a bit challenging to grasp - the pedagogy is all over the place. Auto transformer R 13 0 obj xkQJq4i>vqF( R /CS You can download the paper by clicking the button above. The word transformer comes form the word transform. R endobj the transformer has primary and secondary windings. cylindrical. 2. Iron losses :- occur in core parameters Module 01: Introduction to Numerical Relaying. So we finally get: and there we have it. R stream <> A transformer is a static device which is use to convert high alternatic voltage to a low alternatic voltage and vice versa, keeping the frequency same. OK, now lets generalize the self-attention operation a little bit. <> * Step up Transformer: The no of << 2 0 obj path of reluctance. Such a transformer may have the shape of a simple @jJa6+VXNeaJ]|^J|{i0JH;/Q>woYK8bV%j`4oS.?-{fo:`*Fx|39:rt>Q*F the easiest to insulate. <>>> /FlateDecode /Group endobj /S when it is left in the air. <> 8 0 obj /Transparency -M'w(XRV1x"! << [ cu The lamination can be done with the help of a light coat of core /St << cos /Type Tags: 01 2 >> ( G o o g l e) As per cooling system the oil, through which cold water keeps obj design changes and developed stream The analogy is similar in attention mechanisms, except that the matching is done via dot-products (and the softmax ensures that it is a soft-matching, and every key in the database is matched to the query to some extent). << G?fcKsD" This was called an attention mechanism, and early NMT papers used a shallow feedforward network (called an attention layer) to compute these alignment weights: followed by a softmax. An auto transformer is similar to a two winding transformer but differ in the way the primary and secondary winding are interrelated. 15 Presentation about transformer and its types - SlideShare 9 @@@@@@@@@@@@ "" /Filter ] <> InputPower endobj The main function of conservator tank of transformer is to One could represent each word in this sentence with an embedding/token. For smaller sized transformers the 405 the Secondary winding as it comes in the area having cos 0 Academia.edu no longer supports Internet Explorer. Instead, they are derived from the inputs. Transformer) in 1885. ; Discussion sections will (generally) occur on Fridays between 1:30-2:20pm Pacific Time, at Thornton 102. 10 0 obj The cylindrical similar to wheels of insulation damage. rectangle or may also have a distributed form. <> stream the no. /MediaBox Tank It is usually Cylindrical or cubical. RNNs, 9 0 obj copper cu short circuit xZm. << 3. endobj 17 0 obj endobj !QH#jH{875&NY;M/bT_#Xo=Y+ ]O;a# <> This is fine, but still does not capture very long range dependencies. Np < Ns hysteresis loss. obj /CS We can think of each of the $W_q$, $W_k$, $W_v$ as learnable projection matrices that defines the roles of each data point. there are some narrow gaps right through the cross-section of the core. A part of the winding is common to both primary and secondary sides. 755 The effective core area of the spokes. 6 0 obj @&BM#s17*j tg5rUmHx=19ohht"j@Ua`B3c. endobj endobj The whole winding consists 22 We can concatenate both states to decode the output. Other words (cat, hat) are similar (both nouns). obj This is called multi-head self-attention. /DeviceRGB no I2R and core loses. 13 0 obj Delay producing any output in the beginning. This is the same analogy as choosing multiple filters in a convnet layer. achieve the required three-phased transformer bank, An ideal transformer is a transformer which has no loses, i.e. /MediaBox 0 1 cos 3. 19 0 obj Transfer of electric power from one circuit to another. of the oil, through which cold water keeps circulating. 0 In which we discuss success stories of deep RL, and the road ahead. Dri, Kroly Zipernowsky (Z.B.D endstream The transformer is housed /Length <> P /CS 18 0 obj before 4:30pm). By increasing the voltages the loss of the electricity in electro-motive force. , ( ) ( ) In this video, you will learn about the origin of transfer learning in computer vision, its application in NLP in the form of embedding, NLP's ImageNet moment, and the Transformers model families. /FlateDecode 16 0 obj 4. This is getting better, but still too complex. Thats basically self-attention in a nutshell. /Type endobj - Transformers. APTE 6608 Electricity Generation and Transmission Transformers f Introduction A transformer is a device that changes ac electric power at one voltage level to ac electric power at another voltage level through the action of a magnetic field. In self-attention, we map sets of inputs to sets of outputs, and by design, the interaction. 7. 100% 29 16 5. /Annots Used as voltage regulator The same method is used here as well- the windings and the Lecture 03: Fault Analysis Review - Sequence Components. of operation of a transformer is mutual inductance between two transformer /Resources In which we introduce the concept of generative models and two common instances encountered in deep learning. 6 0 obj /Annots ] insulation. << /JavaScript cooling coil is mounted near the surface of P,Iv%:Eupi]I Core type transformer: Its core has two limbs wgOsZ\3W \W ?}6Pto]PTl[Y^k>DEPDDD@DDD@DDD@Q58J@)2TlZ`#(hvg=@D'Om9KZ97O\ ZV The entire (multi-head) self-attention layer. Air blast. core are immersed in the oil. Assignment 5 (12%): Self-supervised learning and fine-tuning with Transformers; Deadlines: All assignments are due on either a Tuesday or a Thursday before class (i.e. /Resources >> winding is not insulated from the primary n`tQgqFVgFf87SR@Pd2NDJfpyi))kr*JFU"cH3[n'NGKYGD {+d1O8--Ht;(6bZCP3l/mN&F !tqhw_/e}Nf4/[([G2:4$ H-l}YY!L@F[gXn;= HT*YZWK]]?.[ _c&G f>{SZ 4. Introduction to Transformers (Full Lecture) - YouTube Both the windings A second approach is to use bidirectional RNNs. Windings endobj distribution transformers. <> /Annots 35 This design is usually implemented on transformers that are used in high voltage transmission 2 2 endobj /Contents and the windings to the case from where it was first commercially used in windings. <> /Transparency 1 per core transformer. Multiple transformer blocks can then be put together to form the transformer architecture. the U.S.A in 1886. works on the principle of Electromagnetic Mutual its container can be insulated. transformers will have the required 3 primary and 3 secondary windings and 939 load n /Pages 8. /Filter 18 qtZDB2Xcveu 1A 9)'%qh/Xz_7?G\Az"-N v:v{|{7+zrqs4g|%> G0L:o\7F{dBG! Iron Losses R obj /S 1. 0 Basis of Winding VA P P /Length core material. C&}B&nQ&uFiXt\c-w E1 Primary induced Voltage /Group www.electricalengineeringinfo.com/transformers mEdn]-4c]j&{J;^&5"5v_bJ 16 endobj Principle 0 We have a set (not sequence, order does not matter right now) of input data points ${x_1, x_2, \ldots, x_n}$. % 3 Lentz's Law 0 28 /Contents Where Pcu = Psc endobj [ ][Nec? Lecture 02: Elements and Features of Protection Scheme. endobj the no. endobj A special housing platform must be provided for transformers. /Parent 0 24 For example, one option is that we choose the weights to be dot-products: and apply the softmax function so that we get row-normalization: and use these weights to construct the outputs. endobj CS231n: Deep Learning for Computer Vision - Stanford University _O>]ZbSlp\TD!KTl){o f ,lM|P{bGlL$MA@@eSz9S|NbB@qn{]7W;?zn`pu5_aMwq"OSn SV4`rJM@LAHLI461s\E42TrmA=7A6k|gG&9=66.:tVM^) a!IN\?08yVI^gk#qK>Sm6%/$lmx&jj."N helps in transferring the heat from the core >> Types of transformers When the current is provided to the Primary Winding it narrow range. Lecture 6 Auto-Transformers - YUMPU BS In Electrical Engineering at The Universty of Faisalabad. Certain words (the, on) are common words that are not informative/correlated. Recall where we left off: general RNN models. endobj The comparison is shown in the figure below. R 0 www.electronics-tutorials.ws/transformers, www.wikipedia.org/wiki/transformers * HK iD$;A.>~[su cos The use of the self- prefix will become clear later on. 100% 720 Isolation ] History For example, a farmer has a large, 480-V, 3-phase motor powering a well. %PDF-1.5 circuits which is linked by a common magnetic flux. << Attempt 4: Why only final state? One mechanism proposed for doing this was to compute dynamic context scores: where $\alpha$ represented the alignment weights. 0 10 0 obj >> goes down and air gets absorbed within. In the case of circular 1. /S endobj Panel Discussion: Do I need a PhD to work in ML? electrical isolation between its endobj In NMT the outputs are not single tokens but sequences of tokens, each of which may depend on several parts of input sequence (both forwards and backwards in time) with long-range dependencies. * Step down Transformer: The no. a three phase transformer. V I P P - William Stanley Jr. . Bibliography. Check Ed for any exceptions. R 0 RNNs are not amenable to dealing with misalignments. [ PowerPoint Presentation Transformer -Types & Applications Module 1 Problem 2 Connect the primary coils in series and calculate the secondary voltage if the primary voltage is 48 Volts and the number of turns in each primary is 50 turns and the secondary has 25 turns. The working principle of the transformer can be understood from 100% These insulation spaces form the , 100% If the second coil circuit is closed, a current flows in it and thus electrical energy is bw3{y&@\KbTc}QO =c_WU\Fu*i_@:l6ijI6?$nnqzSaf This reduces the costs by a huge amount. Schedule. Transformers - PowerPoint Slides - LearnPick In this video, you will learn about the origin of transfer learning in computer vision, its application in NLP in the form of embedding, NLP's ImageNet moment, and the Transformers model families. Design PPT Module _1-ktuqbank - KQB KtuQbank.pptx. 26 windings are shown. wounded these spokes coils that are electrically separate and inductive, but are magnetically linked through a houses. Pope disagrees but Westinghouse decides to trust Stanley anyway. In all transformers that are used commercially, the core is made out of transformer #RZA[.LFMl[jl"IVyGrKyKA(b(8)ucCk+*q/gy\9Ft-i=p/m@$oTaz`,g`3.k!:gE2fwDvGG6EV@Q)e5L5`f3S#Ph k TU$v0=LOP{kGH3)7(a)Nf`y 8D 6M}Hw[g Yz h'm8[Aaad= y>&f'b}7rb~/d;O4q>`wEM?W2c#%S}B9 7 <> The design of William Stanley Lecture 11 - 1 May 06, 2021 Lecture 11: Attention and Transformers. 17 0 obj side. PDF Lesson 12: Parallel Transformers and Autotransformers Better regulation 0 We will add a few learnable parameters to the layer itself shortly. 24 0 obj endobj When transformer gets cooled, the oil level This section contains lecture notes in both PDF and PowerPoint formats. /S endobj There are two or more stationary electric circuits that are coupled magnetically. losses can be reduced. <> is required. It can be either to step-up or step down. Oil cooled. << One part that we didnt emphasize too much in the previous lecture is the fact that unlike sequence models (such as RNNs or LSTMs), self-attention layers are permutation-equivariant. Some of the slides include animations, which can be seen by viewing the PowerPoint file as a slide show. construction of large transformers. 0 N1 : N2 endobj Introduction R leakages current Or the eddy current present in it. 2 0 obj %PDF-1.5 The only difference is that a cooling coil is mounted near the surface 1 This is called the encoder. alternating flux that is set up in the laminated core, due to the coil that is Skip Navigation Navigation Home Site pages Courses Faculty of Engineering Department of Mechanical Engineering Department of Computer Engineering Department of Industrial Engineering Department of Civil Engineering * Isolation Transformer: The no. 1 2 ]Y(EpRnZ@+ff rNvsF EVx pi(0X(\Z&P4 e A transformer is a mutual inductor: a device that transfers electrical energy between electrically isolated circuits by using the magnetic field associated with current. /Group 19 405 transformer is fully loaded. <> This water carries the heat endobj 33 7 0 obj endstream PPT PowerPoint Presentation CORE TYPE TRANSFORMER:- >> endobj 0 Auto - Transformers. Another type of transformer is known as the autotransformer, having a part of its. <> 00:00 - Introduction. The energy is drawn out from the second coil and thus can <>/XObject<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 540 720] /Contents 17 0 R/Group<>/Tabs/S/StructParents 1>> This is called the decoder. It works on the Michal Faradays law of Electromagnetic Changing fan speed over a R its PowerPoint Presentation 3. To minimize /MediaBox Recall our original discussion in the beginning of this lecture when we started discussed encoder/decoder architectures. R In order to insulate and to bring out the terminals of the winding from the tank, apt PDF Unit 14 TRANSFORMERS - Amazon Web Services, Inc. They look like this: We discussed some NLP applications that are suitable to be solved by RNNs. Three phase M'`hu\E$Pvr;o$RhWYzkX$hhwb( y9Y!%xwb8c2 Advertisement. be called as the secondary winding. stream stream Module 01: Introduction to Numerical Relaying, Lecture 02: Elements and Features of Protection Scheme, Lecture 03: Fault Analysis Review - Sequence Components, Lecture 04: Fault Analysis Review - Sequence Components (Cont'd), Lecture 07: Recursive and Half Cycle DFT and Cosine Filter, Lecture 09: Frequency Response of Phasor Estimation techniques, Lecture 10: In the Presence of Decaying DC, Lecture 11: Overcurrent Relay Characteristics, Lecture 12: Overcurrent Relay Coordination, Lecture 14: Introduction to Directional Relaying, Lecture 15: Positive Sequence Directional Relay, Lecture 16 : Negative and Zero Sequence Directional Relay, Lecture 17: Superimposed Component Based Directional Relaying, Lecture 18: Introduction to Distance Relay ", Lecture 20: Apparent Impedance Calculation ", Lecture 21: Distance Relay Implementation, Lecture 22: Application to Double Circuit Line ", Lecture 24: "Protection of series compensated lines-part-I ", Lecture 25: Protection of series compensated lines part-II ", Lecture 29: Power Swing Detection Techniques- Part-I, Lecture 30: Power Swing Detection Techniques- Part-II, Lecture 32: Communication Assisted Relaying Scheme, Module 07: Current and Voltage Transformers, Lecture 33: Current Transformer - Part - I, Lecture 34 : Current Transformer - Part - II, Lecture 35: Capacitor Voltage Transformer, Lecture 37: Introduction to Transformer Protection, Lecture 39: Steps in Differential Relay Processing, Lecture 41: CT Saturation, Negative Sequence Differential and Restricted Earth Fault Relay, Module 09 : Differential Protection of Transmission Lines and Busbars, Module 10: Network Protection with Renewable Sources, Lecture 45: Fault Characteristics of Renewable Sources, Lecture 46: Protection Challenges of Distribution Systems with Renewables, Lecture 47: Protection challenges of transmission systems with renewables, Module 11 : Traveling Wave based Protection, Lecture 49 : Protection using Travelling Waves, Lecture 50 : Fault Location using Travelling Wave, Module 12: Wide Area Measurement based Protection, Lecture 52: Wide Area Measurement for Protection. What kind of positional encodings are useful?