Questions tagged [transformer]

A transformer couples two or more AC signals through a magnetic field. Often used as galvanic isolation and to transform one AC voltage to another.

Filter by
Sorted by
Tagged with
0
votes
3answers
26 views

Maximum Supply Voltage Output by Transformer - Sanity Check

First off, I am not an electrical engineer by trade, or even by education. Pretty much everything I know about EE is self-taught, and I know enough to make a hobby out of it, but may be missing basic,...
1
vote
0answers
15 views

Misunderstanding document about leakage inductance in a flyback converter V2

I m back again on this document ! :D The document teaches me a lot of things and I think it will help me to better understand the losses across the switching components. I really appreciate if someone ...
1
vote
1answer
43 views

Misunderstanding document about leakage inductance in a flyback converter

I am currently reading a document about leakage inductance in a flyback converter from ON SEMICONDUCTOR . Here it is : https://pdfs.semanticscholar.org/c061/313303ee8c231b069be4f0d67d9e4cddcbf0.pdf (...
1
vote
2answers
36 views

Center-tapped transformer and inductance calculation for transformer driver

Using a push-pull transformer driver, for example the LT3439 like below with a center-tapped transformer, more precisely this one here So we there is a center tapped transformer (with 1:1.3 ratio ...
0
votes
2answers
47 views

How to check if a SMPS transformer is working properly

I recently came about one such transformer while fixing a boiler PCB and I suspect it's damaged. How do I test it?
0
votes
1answer
27 views

SMPS coupled inductor selection

I am in the process of designing a switched mode power supply as I need rather high power(12V 2A). I took a look at the TI tool that throws a basic circuit at you. I understand the danger of such a ...
0
votes
2answers
59 views

Leakage inductance is function of the air gap

I would like to know why leakage inductance is function of the air gap transformer. How does it influence the leakage flux ? What is the relation between them ? Thank you very much :)
0
votes
2answers
62 views

Is the transformer's secondary winding too large?

I recently took out the windings from an old microwave oven transformer and was planning to use the core for a 120 to 6.3 VAC step-down transformer (total power 160 W max). The secondary winding (...
0
votes
0answers
36 views

Transformer operating frequency clarification

I'm trying to design a small audio transformer. Specs are as follows: ...
0
votes
3answers
62 views

Can I still use this power supply if I clean off the rust from the transformer?

I have power supply for a vintage Timex Sinclair. The unit was sealed but the cable felt loose so I pried it open to inspect the connections. There was a knot on the other side so it was just the ...
0
votes
1answer
50 views

Impact of Transformer Ratio to Performance of Transformer

Based on my initial calculation, the primary inductance of my transformer will be around Lp = 351uH. This 351uH is designed with switching frequency of 55kHz for AC-DC flyback converter (DCM). By ...
1
vote
1answer
43 views

Finding the optimal voltage for a sealed transformer

I stumbled across a sealed transformer (step-up) which i believe came out of a neon power supply. Its completely covered in epoxy like goop and the internals cannot be seen. However,on the tin it ...
1
vote
1answer
47 views

Back EMF in a transformer with an external power source to the secondary coil

When discussing an ideal transformer, Wikipedia says “varying flux at the secondary winding induces a varying electromotive force (EMF, voltage) in the secondary winding due to electromagnetic ...
0
votes
1answer
36 views

Can I connect 2 standard 12V 2A wall adapters in series?

I live in the UK and I need a 24VDC power supply. They are very expensive. Can I just use 2 cheap standard 240VAC - 12VDC wall adapters in series with no issues to achieve 24VDC? For example, and ...
0
votes
3answers
58 views

Idle down transformer [closed]

How much does a 3000 watt down transformer consume when not used? In NZ and use my usa clothes washer. Should I TURN IT OFF when not used?
0
votes
0answers
29 views

How to identify and check if transformer is working fine?

I have 3 in 1 SMD rework station and in that Machine veriable DC power supply is not working and I am unable to check if transformer is working correctly or not and if I have to replace how to find ...
0
votes
1answer
21 views

Switching Frequency for Flyback Quasi Resonant Converter

As I know, the major difference between normal flyback converter & flyback quasi resonant converter is for flyback quasi resonant converter, the switching frequency is variable. This means that ...
0
votes
1answer
22 views

Connecting terminals to transformer on Power Inverter circuit LTSPICE

I am simulating a Power Inverter circuit using LTSpice, but I am confused as to where the corresponding terminals from the resistor and mosfets go. I am trying to simulate this circuit: Based on the ...
0
votes
1answer
32 views

Comparing transformer set ups

Is it practical to connect the output of a ferrite-core 1:40 transformer in series with the input of a 1:6 ferrite-core transformer as a means of acquiring 240 V?What would the pitfalls be of this ...
1
vote
1answer
36 views

Evaluation of the primary inductance of a transformer whose core is saturated

I would like to know if it is possible to theoretically estimate reasonably the primary inductance of a transformer when its core is saturated. Otherwise, what is the best way to do it by measurement?...
1
vote
0answers
51 views

Suppressing the turn off transient for a trailing edge 120V AC dimmer

I am designing an 120V 60 Hz AC trailing edge dimmer based on the reference design above. The gate is driven starting at 0/180 degrees of each cycle and turns off at a programmable phase later in the ...
1
vote
1answer
60 views

Changing a power supply from dc output to ac output

I've read an article on changing a 12 v ac-dc power supply to 9v ac-ac by just tapping the transformer output directly, bypassing diodes and capacitor. This only applies to older type ac power ...
0
votes
0answers
45 views

Sizing Connector and Cables for Inrush Current

Country: Canada Specs of application: Station can draw 2.2 kW, on full load, which rarely (if at all) happens. Station must run on 230Vac Autotransformer is rated for 7.5 kVA Expected inrush is ...
0
votes
0answers
42 views

Calculating A Transformer Core Power Capability

I'm trying to build a transformer for a full bridge dc-dc converter and it's my very first time to design a transformer and I got limited knowledge. I'm checking some ferrite cores and I've found ...
-4
votes
2answers
59 views

Iron losses is equal to copper losses [closed]

Practically how we see Copper losses are equal to iron losses in a transformer
0
votes
1answer
41 views

Using 12v 50w motorcycle light with two 7.4v RC batteries

I recently purchased two motorcycle lights (12v DC 50w) and only needed one. Now I have some 7.4v 4500mah 45c batteries leftover from my RC hobby a while back. I would like to create a 3d printed ...
1
vote
1answer
81 views

High side MOSFET driver with transformer

I am reading the application note " Fundamentals of MOSFET and IGBT Gate Driver Circuits" written by Texas Instrument. In order to control High Side MOSFET, the application note suggests to use this ...
0
votes
1answer
35 views

Measure leakage inductance of flyback transformer with multiple secondary windings

I have a transformer consisting of one primary winding and 3 secondary windings. Now I want to measure the leakage inductance at the primary side, so I need to short the secondary windings. Most of ...
1
vote
2answers
90 views

Equivalent circuit of a transformer

In equivalent circuit of a transformer, there are two inductances, \$L_p\$ and \$L_s\$. These are called Leakage inductances, as the name suggests due to the leakage flux from both the coils. 1) Are ...
0
votes
1answer
52 views

Alternative ways to step up voltage?

I want to drive an EOM crystal at 20 MHz for phase modulation. I recently bought a step up RF transformer (1:4 turns ratio), but it's not working fine above 2 MHz. I tried winding a transformer myself ...
0
votes
1answer
32 views

Open circuit test of a single phase transformer [duplicate]

In open circuit test of a transrormer, will the values of the parameters be different if we perform the test on the high voltage side and then we perform the test on the low voltage side ?
0
votes
2answers
40 views

Transformer auxiliary winding

I'm designing an AC-DC based on the UCC28780 active clamp flyback controller . I have a question about the primary auxiliary winding that is supposed to power the UCC28780 and the gate driver. My ...
0
votes
2answers
64 views

Stepping up from 12vdc to 100vdc/-100vdc

I am looking to power a phone ringer circuit that requires +100 V DC and a -100 V DC. I have found a circuit here but this converts it to 120 V DC with a transformer. Is it possible to get +/-100 V DC ...
0
votes
1answer
24 views

Delta wye transformer, voltages explanation?

So I'm doing a delta wye transformer simulation in simulink, and I need some clarification about transformer voltages. Here's a image from a youtube video We have phase voltages on primary that ...
0
votes
2answers
56 views

How to rewind microwave transformer to isolation transformer

I'm thinking of getting an auto transformer and rectify it to make mains isolated 240V 8A DC power supply. I would like to know if its possible to rewind an old microwave transformer to 1:1 isolating ...
0
votes
2answers
90 views

Looking to generate 25 Hz square wave at about 90 V AC

I am looking to build a square signal generator tuned to ~25 Hz at a voltage of ~90 V AC that can output ~400 mA. I've searched around the internet and tried a few things but I've had no luck. My ...
0
votes
1answer
24 views

If a device takes in a range of voltages, is there an optimal choice of voltage to supply?

I bought an LED light for photography, which came with a battery. I realised later it also has a DC port for a power supply. The range is 6.5v-17v. I happened to have an adjustable laptop power ...
0
votes
2answers
77 views

Designing an air gap transformer Misunderstanding

Suppose my core is actually with a design which make it saturated and the voltage on the secondary is too high. So I have to decrease the secondary voltage: For this I can increase the number of ...
0
votes
1answer
34 views

How to find phase shift(angle) between two signals in simulink?

So I'm doing a delta wye transformer in simulink and phase shift between these two signals should be 30 degrees, but how to show that, or calculate it? And how to find angle of each signal?
0
votes
1answer
51 views

Analogy electric circuit and magnetic circuit - Power

Here are a table which do the analogy between electric circuit and magnetic circuit. Nevertheless, there is no analogy with power dissipation … Nevertheless, It is said that in a transformer with an ...
0
votes
0answers
17 views

Parameters for VAC 5046-X005 gate pulse transformer

I'm trying to parameterize this device to find a suitable equivalent. Trouble is, there seems to be no datasheet available, and one of the two secondaries are measuring open, so complete measurements ...
0
votes
2answers
37 views

How to show that voltages on diagram are 120° apart?

So i'm doing a matlab simulation of delta wye transformer and would need to show the phase shift between voltages. Here is a picture of input voltages so how would I show on this graph mathematically ...
0
votes
0answers
58 views

How does this electrical ballast need to be wired to the flyback transformer?

I just got myself a flyback transformer and an electrical ballast for fluorescent lamps as I heard those can be used together. The electrical ballast is supposed to generate a high frequency which ...
0
votes
1answer
62 views

Transformer switch off spike

From Wikipedia: When a transformer, electromagnet, or other inductive load is switched off, the inductor increases the voltage across the switch or breaker and cause extended arcing. When a ...
0
votes
2answers
102 views

How to calculate transformer inrush current?

I have a transformer with 220 V primary and three secondaries; 1. 24 V | 1.2 A 2. 24 V | 600 mA 3. 12 V | 200 mA Each secondary have 4400uF capacitor and 100mH ...
2
votes
1answer
80 views

Short circuit protection of a controller for flyback converter

I would like to have your opinions about this short circuit protection. Here is the schematic associated given into the datasheet. And you can find into the same datasheet how their short circuit ...
-4
votes
0answers
84 views

Ignition damage [duplicate]

I made this circuit using a 5nf capacitor. (Ignition coil in series with a light dimmer and at least a 0.1 mf capacitor, powered by 240v) https://www.instructables.com/id/Variable-voltage-ignition-...
2
votes
2answers
85 views

Can transformers be used to adjust capacitors?

It seems capacitors are subject to a "quality triangle", where we can only pick two out of three desirable traits: High voltage rating High capacitance Cheap For example, a high-voltage high-...
0
votes
1answer
60 views

Transformer open circuit output voltage and current limiting resistor at gate of Triac

Im kinda new to electronics and have some questions before i solder my projekt together. I want to make an Arduino controlled soldering iron and designed the circuit below. The optocoupler i used is a ...
1
vote
1answer
127 views

Using Motor Oil as a Transformer Oil Substitute

I need a rather large volume of oil to insulate a few 15 kV wires/coils. Unfortunately, the volume of oil required puts transformer oil outside of my price range. I've noticed that others have ...

1 2 3 4 5 46