Transformers Definition and 254 Threads

The alternating current will create an induced voltage given by ##V=-N\frac{d\phi(\vec{B})}{dt}=-N\frac{\Delta\phi(\vec{B})}{\Delta t}=N\frac{2 B_0 S}{\Delta t}=\frac{240\cdot 2\cdot 65\cdot 10^{-3}\cdot 10\cdot 10^{-4}}{10\cdot 10^{-3}}=3.12 V## and since this is the effective voltage, the...

I have read that transformers are the key behind recent success in artificial intelligence but the problem is that it is quite opaque. I wonder if anybody knows how to build and train one from scratch or if there is any book, video, or website explaining it. Thanks

Hello, If we have a pole top mounted distribution step down transformer for residential use what happens to the voltage on the secondary side if the primary side voltage increase? Thank you

Hi all, I just read this article about how electrical transformers work and have some questions. https://www.dfliq.net/blog/the-basics-of-electrical-transformers/#:~:text=The%20three%20important%20components%20of,magnetic%20flux%20is%20initially%20produced. i). What exactly is magnetic...

In Simulation of transformer and electrical motors in software like ansys maxwell we usually have to model conductors, but does it matter how to draw them? I use Ansys software for finite element simulations. Maxwell, Simplorer, RMXpert and other toolboxes. but I always have a doubt on how to...

So I've done part a) Primary current = 200000/415=481.9 Cos θ = -0.8 Sin θ = 0.6 Reg=(481.9 ( 0.014*-0.8 + 0.057*0.6))/415 = 0.0267 Reg% = 2.67% Part b I simply used the same equation but for secondary: @ unity p.f., cos θ =1, sin θ = 0 secondary current = 200000/11000 = 18.18...

Hi hi, I was trying to use a transformer, that typical transformer that we have in house for a project, but then I notice something, well all this can be just a misunderstand from me. Actually a transformer have a voltage and a current, at least that is what it says the labels, "18V and 3A" for...

Hi, Question: I think my misunderstanding boils down to a few short questions: 1) Is the equivalent circuit for a transformer of the same topology for a step-up and step-down transformer? I think it should be as the turns ratio is simply a constant. 2) How do the open/short-circuit tests work...

Hi! I was wondering why even a real transformer has a very low leakage flux, what makes it be this way way? Is it the ferromagnetic material? If so, why? If the core was made of completely vacuum would the leakage be 100%?

This question is given as an exercise in my book. I can't figure out whether this is a poorly worded question or if I misunderstand. The answer I can come up with is that power is dissipated over the load so more power is needed to be supplied by the ac source. This seems too hand-wavy to me...

Suppose there exists a proton beam that is pulsed on and off. If this beam is aimed through a current transformer as in the attached image (the proton beam would act as the main primary conductor in this case), what would be the output of the transformer, and how would it affect the beam...

Homework Statement Ok I have the following circuit and data (when the subscript is "ef" it means "rms" values): I am asked to determine the parameters of the transformer r1 L11, L22 and LM with the given experimental data. Homework Equations 3. The Attempt at a Solution [/B] I had no...

Residential air-conditioners universally have a low voltage side and a high voltage side. The low voltage side of a residential air-conditioner is 24 volts. The high voltage side of a residential air-conditioner is 220/230/240 volts. I have heard several people say that a shock from the low...

A transforming winding is like a short circuit.. except there is inductance caused by alternating current and the frequency that produce some resistance. What would happen if the frequency is lowered.. would there be a threshold value that would begin to make it as short circuit? like 30 Hz...

<Moderator's note: Moved from a technical forum and thus no template.> Hi all, I have attempted this question but have a few queries on how transformers work, and what the dot notation represents. (a) The flux would be clockwise around the iron core. (b) This is the question where it gets a...

In residential split-system air-conditioners and heat pumps, there are transformers inside both the condenser and the air-handler that step the voltage down from 220/230/240 volts to 24 volts. Someone once told me that in residential air-conditioners/heat pumps, the high voltage side of a...

Homework Statement Discussions of the possibility of a tangential E-field external to a current-carrying conductor must include a voltage source and a return path. Here the problem is reduced to (we believe) the simplest possible geometry. Assume that a circular conducting loop has constant...

As common I mean inductances and eq resistances. I've been searching for high voltage transformers (to use with a 12-pulse rectifier) but I only see catalogues just trying to sell the thing. Do you have any recommendation as a book or another reference?. Thanks in advance!

Homework Statement Give two reasons why transformers are an important part of the power distribution grid My lessons don't have any information regarding this topic. I have read everything in my lesson and can't find anything to answer this question. please help. thank you

What happens to the current through a transformer windings if the whole system is under a uniform magnetic field in the direction of the coils and with frequency equal to that of the AC in current? I think the current induced in the primary solenoid should generate a field that would make up...

Will someone please help me understand the significance of shorting an auto transformer? This feeds a motor. At reduced voltage, the motor starts at 65% of line voltage, a run contactor pulls in bypassing the transformer and the shorting contactor pulls into take the transformer out of the...

A 4160v chiller motor is drawing too much power at start-up. Utility company only let's them run it once or twice a year because of it. It dims all the lights etc.. It was originally a primary reactor starter (2 contactors). The PR was replaced with an auto-xfmr and wired the same. So now it’s a...

How is the phase difference between the current in the primary coil and induced e.m.f. in the secondary coil be 90*??

Hi all, I have been battling this topic for one year now. Frequenctly revisiting it and trying to find a clear answer on the internet and in but without finding it. Could be that my knowledge level is too low. However, I'll give it a shot here. So what I have been learned is that during...

my transformer book does not cover an area i am interested in and was wondering if someone would direct me to literature that would help me understand something and if you wouldn't mind trying to explain it to me yourself that would also be appreciated. you have three single phase transformers...

I want to make a powerful electromagnet using a transformer, to start I wish to to make a weak magnet using it then work up from there to ensure I make little to not mistakes since I am inexperienced with engineering. I was planning on using a transformer I got from a power supply. I have taken...

Hi guys, Non engineer here trying to understand an engineering principle. I think I must be going wrong somewhere in my thought process. 1. Faraday tells us that the EMF generated in the secondary of a transformer is equal to the change in magnetic flux divided by the change in time. 2. The...

Homework Statement I am working on the following problem: And ideal single phase transformer 240V/2880V is supplied with a 240V source via a resistance cable of 3ohm. If we connect a R=720ohm resistance to this, determine the primary current and the dissipated power in R. (I'm sorry if some...

Homework Statement An electric doorbell requires a 12 V 60Hz ac supply a)What turn ratio is required on a transformer to operate from a 120V 60Hz ac supply? b)Step-up or step-down? c)If the transformer is connected the wrong way around the circuit what voltage is supplied to the...

Hi Got some questions regarding grounding transformers (wye-delta), or maybe I should write, I need someone to tell me if my understanding is correct. First, under no fault operation: Only a small current will flow in the wye side of the grounding transformer, aka magnetizing current...

I apologize for being somewhat scatter-brained here, I just have too many questions on this topic. I know high-frequency transformers use ferrite cores instead of laminated silicon-steel, but what other differences are there? Does their reactance still follow the standard formula: 2*Pi*F*L ...

Hi Take a look at the picture below, I am curious of what transformer connections are used at each step up/step down transformer. I am sure that there are several way of connecting them and each have their pros and cons, but what are the most usual connections? Lets start at the consumer and...

Hello everyone, Recently, i have designed a capacitor bank for a company which they already have their main switch board with metering stuff. The ammeter of the main switch board has its own CTs but for the capacitor bank I need to install a CT separately. The spec of existing CTs for main...

I have a transformer that has 120/240 on the primary,but the secondary has multi volt ,33v 0v,13.5v 0v,2.7v 0v 2.7v,9v 0v 9v.The power consumption is 28watts only.How you work out 28watts with all secondary windings to find amps so I can calculate for total VA,and wire gauge?.Some one out there...

This is a snapshot of the diagram in the high school textbook. and here is the accompanying text I would like to understand the "minus" signs in - N1dΦ/dt and - N2dΦ/dt This is my understanding - When there is a crest of the sinusoidal voltage i.e top terminal of the input voltage is...

What effect do harmonics have on wye-wye transformers with neutral grounded? What about not grounded? Also, in a wye-delta, why is there less distortion in the delta side voltage if neutral in the wye side is not connected to ground? I understand why the Y transformers have distortion and the...

Hi everyone, I want to self study about the electricity and all other basics which are required to understand the making and working of transformers. Then I want to study the making and working of transformers. Please suggest me some good book which I should refer to get the required...

Homework Statement A 7200-240 V, 60 Hz transformer is connected for step up operation, and a 144∠46° Ω Load is connected to the secondary. Assume the transformer is ideal and the input voltage is 220 V at 60 Hz. Determine a)secondary voltage b)secondary current c)primary current d)input...

So on the left is a circuit which shows a voltage source and 2 coupled inductors in a parallel magnetic circuit shown on the right (transformer with a parallel core). Can someone tell me if I am modelling it correctly with the following equations? Rc1,Rc2,Rc3 are the reluctance of each branch of...

So Assume that I have an AC generator and I am giving it enough power to keep spinning with the same rate. So I have limited power usage. The generator creates maximum voltage V and because power is limited that leaves me with only 1 specific current. Now if I connect this generator to a...

1. Homework Statement Find V2. Everything else is available in the picture Homework Equations r1=r1+a^2*r2 x1=x1+a^2*r2 z2=a^2*r2 I1=vp/z2+r1+x1 The Attempt at a Solution So I have used the first three formulas but it's the last one I am getting stuck on. Since my x1 is an imaginary number...

Why does the load connect back to the primary side of the transformer?

I have studied ideal transformers (transfer 100% of energy) and that the power loss in the secondary coil is I^2*R.. Then I asked myself, why can't we use these equivalent formulas for power (IV and V^2/R)?? I tried to use them but they gave me different values for power loss I searched for an...

Homework Statement A farmer installs a private hydroelectric generator to provide power for equipment rated at 120 kW 240 V AC. The generator is connected to the equipment by two conductors which have a total resistance of 0.20 Ω. The system is shown schematically in Fig. 1. (a) The...

In a transformers output, is it the current that is fixed or the voltage? I have been trying to resisitively heat some tungsten foil and I am stuck at trying to find out the amount of current I need in my transformers output. The problem I am facing is that I know that the tungsten resistivity...

Note: I have a feeling this is below Electrical Engineering requirements, but I couldn't find a more suitable category, so I think I'll extort the advantages of a forum base with electrical understanding more than I think may be required(ofcoarse I know very little about the field, so I may fall...

As I understand in transformer when there are two sections of wire, changing magnetic field induces voltage into another wire. Can anyone tell why induced voltage depends on how many loops of coil there are ? Less loops of coil there are in secondary coil, less voltage will there be induced by...

Homework Statement Homework Equations Wye: V_Line = sqrt(3) x V_Phase Delta: V_Line = V_Phase The Attempt at a Solution My answer doesn't quite match up with the solutions in the book, and was wondering what I went wrong here? Any help is greatly appreciated!

Hi, I'm trying to wire a transformer which steps my mains voltage (240VAC) down. I just finished wiring the the primary to the plug, and thought I should test my connections by plugging it in. The coil was not inside the core or near the secondary, it was just lying on a piece of paper. I...

If i have a transformer, and i need to calculate the core losses using this approximate equivalent circuit, according to the lectures ( taking an introduction to electrical machines course in college) the Pc ( power lost in core) = (V1)^2/Gc, but the professor clearly stated that the core losses...