All Questions
25
questions
4
votes
2
answers
100
views
Energy stored in a saturating inductor
We all know that the energy stored in an ideal inductor is \$E=\frac{1}{2}LI^2\$. However, real inductors with a ferromagnetic core don't have constant inductance. Particularly, when a specific field ...
- 209
5
votes
4
answers
2k
views
Could a very high voltage and very low current allow a non-superconducting magnetic energy storage system?
A very low current with very high voltage can travel through high resistant wires without much loss. Could this type of current be used on magnetic energy storage without superconducting materials?
...
- 370
1
vote
1
answer
65
views
Boost Converter - Coil energy transfer into Capacitor - Help needed!
I am trying to design my own boost converter and so am learning about coils.
Let’s consider this example:
The switch of our boost converter has just opened, there was 100 mA flowing though the coil, ...
- 45
6
votes
2
answers
427
views
"To Gap, or Not to Gap" Inductor/XFMR - Energy POV
This post/question is coming from a question I asked within the comments section of here:
How to calculate air gap in flyback transformer?
The great answer given talks about his solution to the ...
- 180
4
votes
1
answer
271
views
Does a parallel air gap increase or decrease maximum energy stored in magnetic field of an inductor?
I understand that a serial air gap increases the amount of energy that can be stored in an inductor.
The reasoning is as follows: according to Gauss's law for magnetism, divergence of B-field is zero. ...
- 1,822
0
votes
1
answer
50
views
Is this method of proving energy is conserved in an LC oscillator correct?
Assuming no energy loss due to heat or EM waves
$$U=\frac{Q^2}{2C} +\frac{LI^2}{2}$$
differentiating both sides with respect to time,
$$\frac{dU}{dt}=\frac{QdQ}{Cdt}+IL\frac{dI}{dT}$$
but we know that ...
4
votes
1
answer
666
views
Power loss in a capacitor vs inductor
Is there are a general rule of thumb if one of these stores energy more efficiently than the other?
When properties are approximateily comparable, are energy losses bigger with a coil or with a ...
- 43
5
votes
6
answers
3k
views
Why can't current change instantaneously in a given inductor?
I know the mathematical reason behind this. Given the inductor I-V characteristic we know that:
I understand mathematically that a function which is differentiable must be continuous, but what is the ...
- 163
0
votes
2
answers
227
views
Do kinetic energy and inductor energy violate conservation of energy?
I posted this question on the physics page. I feel like it might be better suited to this site, though.
Suppose we have an ideal LC circuit (no resistance) and an open switch where the capacitor has ...
- 291
2
votes
4
answers
1k
views
Intuitive way of "visualizing" how the energy is stored in an inductor?
I've been trying to more or less understand intuitively how energy is stored in an inductor, but I don't seem to get anywhere decent.
In a capacitor I understand, I believe: an external battery pushes ...
- 298
0
votes
3
answers
4k
views
What is reactive energy?
We know the typical equation for instantaneous power (which can be proven): \$p(t)=v(t)i(t)\$. In sinusoidal steady state (let's ignore harmonics for simplicity), \$v(t)=\sqrt{2} V_{\text{rms}} \cos{(\...
- 1,019
0
votes
1
answer
112
views
How do we have the \$E=\frac{1}{2}L_1I_1^2+\frac{1}{2}L_2I_2^2 \pm MI_1I_2\$? Can anyone show me its proof?
What is the total energy that two inductors store?
Solution
\$R_{th}=(12||6)+6=10Ω\$,so \$I=\frac{90}{10}=9,I_1=9\times \frac{6}{12+6}=3,I_2=9\times \frac{12}{12+6}=9\$.
So the energy that two ...
- 558
1
vote
0
answers
60
views
The method and calculation for the total energy that two inductors,which has Mutual inductance, stored in this circuit
The solution for the total energy that two inductors stored in this circuit is
\$E=\frac{1}{2}\times 4 \times 3^2+\frac{1}{2}\times 6 \times 6^2-1\times 3 \times 6=108J\$
I want to ask two things
...
- 541
2
votes
1
answer
86
views
C=Q/U equivalence for inductor
In order to calculate the time it takes to charge a certain capacitor with value C at a given constant current of a value I to a voltage of value U, I can use:
$$ C = \frac{Q}{U} = \frac{I\Delta t}{U}...
- 582
1
vote
1
answer
196
views
Energy loss and power over one period?
Let's say we have a ferrite core inductor connected to an AC sinusoidal source with period \$T\$.
Thus, we have voltage \$u(t)\$ across the inductor and current \$i(t)\$ through the inductor. How can ...
- 280