A transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple circuits. A varying current in any one coil of the transformer produces a varying magnetic flux in the transformer's core, which induces a varying electromotive force across any other coils wound around the same core. Electrical energy can be transferred between separate coils without a metallic (conductive) connection between the two circuits. Faraday's law of induction, discovered in 1831, describes the induced voltage effect in any coil due to a changing magnetic flux encircled by the coil.
Transformers are most commonly used for increasing low AC voltages at high current (a step-up transformer) or decreasing high AC voltages at low current (a step-down transformer) in electric power applications, and for coupling the stages of signal-processing circuits. Transformers can also be used for isolation, where the voltage in equals the voltage out, with separate coils not electrically bonded to one another.
Since the invention of the first constant-potential transformer in 1885, transformers have become essential for the transmission, distribution, and utilization of alternating current electric power. A wide range of transformer designs is encountered in electronic and electric power applications. Transformers range in size from RF transformers less than a cubic centimeter in volume, to units weighing hundreds of tons used to interconnect the power grid.
In my car the OEM amplifier runs dual-voice coil subs. Its a SMT PCB with all ICs on even the outputs, no SMPS so its just 12V for the rails and the outputs are already bridged. Easy to see why many junk it and use an aftermarket amplifier come upgrade time. But I want to try to use it as is...
I have obtained the approximate equivalent circuit of a transformer at its rated supply voltage having carried out the open circuit and short circuit tests on it.
If I plot a graph of primary voltage against primary current for an open-circuited transformer I get a curve. If I use my...
Hello,
I've been thinking about why (elementary) transformer efficiency drops drastically at very low frequencies. I know hysteresis effects play a major role in reducing efficiency at high frequencies, but why low? I realize that as we reduce the frequency of the emf, we're making the...
okay, I Don't quite grasp this concept but!. Vo/Vi = No/Ni.
And I have this problem. A Generator at a power plant produces AC at 24,000 V.A transformer steps this up to 345,000 V for transmission over power lines. IF there are 2000 turns of wire in the input coil of the transformer, how many...
Homework problem:
A transformer on a pole near a factory steps the voltage down from 3900V to 220V. The transformer is to deliver 1180kW to the factory at 91% efficiency. Find the power delivered to the primary in kW.
What I've done:
Well, I thought that power in equals power out. So I...
how does a transformer work? Transformers could make 9v from a battery into say 250v but isn't that getting something for nothing? what about conconservation of energy?
Does a capacitor with 9v potential discharge energy faster than a 9v battery? Can capacitors be replace with transformers...
Well, I didn't know where to post this...but it's here now:)
I removed a flyback from my colour monitor and after removing it I succeeded in breaking what seems to be (or closely connected to) the ferrite core. It is a metallic (I think, it is cold to the touch) piece, black on mine, in the...