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.
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Transformer modelling / coupled inductors
I provided a picture which shows the transformer model and related equations.
[Transformer Model and Equations]
Source: https://www.youtube.com/watch?v=VrIfvNVBSyE
I have 2 questions which are as ...
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Why mutual inductance be less than or equal to geometric mean of self inductances of coils?
I understand when coils are coupled together the leakage of flux into surroundings causes mutual inductance to be less than self ones but why it has to be less than or equal to geometric mean of the ...
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Accumulate load time and retain through a power cut?
I have a question around closing a relay after a load been active for a specific elapsed time; and the time is always known even through a total power cut; ideally din rail components would be able to ...
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How do you choose an audio isolation transformer for a microphone?
I found a few SE Q/A's for audio transformer characterization, but they neither address calculating the impedance match, nor consider signal loss for weak audio sources (like those from a microphone).
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How should we calculate L (inductance) value for a transformer
I am trying to design a transformer using LTSpice with the following specifications:
Vin = 230 V @ 50 Hz
Vout = 12 V @ 50 Hz
Power = 10 W
The thing I do not understand is how to calculate the ...
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Transformer-coupled MOSFET gate drive circuits
I provided two pictures below regarding the transformer coupled gate driver circuit.
I know that capacitor blocks the dc when its fully charged and allows AC to pass.
However, how does the capacitor ...
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Are there any regulations that disallow simple AC-to-AC mains to low voltage power supplies? [closed]
I have found that it's quite hard to find AC-to-AC adapters that convert mains AC to a low voltage AC. Usually most devices use AC-to-DC adapters for understandable reasons: electronics don't run on ...
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Calculation of transformer inductance value
I am trying to find a way to calculate the primary and secondary inductance of transformer.
I learned that it is changing from one topology to another. My topology is Phase-Shifted Full-Bridge ...
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Three phase rectifier output current
I´m designing a three phase power transformer, and i´m having troubles with the choosing the current value. After the transformer, goes through a three phase bridge rectifier ( full wave and not ...
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Different wire length on secondary of a transformer, is this detrimental?
So I’m in the neon industry, and the manufacturers of solid state switched mode HV power supplies recommend using the same length of wire for both ends of the secondary, which would require putting ...
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Why is this transformer placed on rails?
I have recently passed by the following transformer. It seems to be placed on rails and might be able to roll forward and backwars by about 0.5m each. There are no guards at the end of the rails ...
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Reusing a salvaged known yellow transformer from a USB charger and using it in H bridge configuration
I have salvaged a transformer from a defective USB charger (witch was not mine).
the print on it refers to an actual USB charger from the same brand.
additionally 12 V in big also printed on it. No ...
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Would the primary current of the transformer be zero in the no load condition?
Source of the figure.
Setting \$R_{2}\$ and \$L_{2}\$ to zero and assuming the primary circuit is connected to an AC source and the secondary circuit is left unloaded, then the current passing through ...
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What is inside of a typical RF transformer?
I am tempted to decap this 500 MHz transformer, but guessing the internals are typical and well-known by experts here.
I don't understand why many companies don't even spec the two windings' DC ...
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Does the primary of an ideal transfomer have a zero reactance?
In the attached figure, the new primary of XFMR1 connected in parallel with the inductor L1 models the original primary of an ideal transfomer. My question is, when modeling the infinite inductance in ...
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