An inductor is a 2 terminal passive device that stores energy in a magnetic field.

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sine wave rectifier in series with inductor phase calculation help. Thanks [on hold]

will appreciate much answer on the following question. Please refer to the image. Many thanks to all of you. Input voltage 48V RMS Lets consider Input Voltage is 220 Vrms sine wave 50 Hz. What ...
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54 views

Noise in DC causing unwanted LC resonance

I have a circuit like this: The part on the left generates AC signal. The part on the right detects whether AC is running through the branch when S1 is closed. I use a resonating LC circuit which ...
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1k views

Why are charge pumps only used for low current applications?

Typically the most expensive (and hard to get) elements in a SMPS are the inductors. Thus I was wondering if it's possible to use inductor-less switching mode power supplies (i.e. charge pumps) for ...
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2answers
62 views

Discontinuity in the charging of an inductor

I have a buck converter without the output capacitor connected so I would able to see the current of the inductor by the voltage at the load. I'm using a IR2110 to drive the mosfet. simulate ...
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2answers
78 views

Estimate the value of an inductor by its steady state response

I have the following circuit: simulate this circuit – Schematic created using CircuitLab The duty cycle of each sw is 50% and the frequency is 160kHz, at steady state I end with the ...
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1answer
65 views

How calculate inductor discharge time through LED?

UPDATE Overnight I realized I'd been sleeping as I read part of the textbook I've been using or at least didn't quite fully grasp the purpose of inductor volt-second balance. I added the results of ...
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4answers
53 views

Measure indcutor ripple current in a SMPS

I need to measure the ripple current in a buck converter. In general, I add leads to the inductor and use a current probe. My issue now is that the inductor I am using has such a low inductance that ...
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1answer
39 views

Irms to Idc for inductor selection [on hold]

I'm trying to build a buck converter using one of Power Integrated switches and their online design software lists the inductor rating in Irms. However, most inductors have their current ratings in ...
1
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1answer
27 views

AL value: nH/N² vs. nH/T²

I'm in the process of sizing some toroidal ferrites. My problem is that I am seeing the AL value on the datasheets shown two different ways as nH/N² or nH/T². Are these two units identical? I believe ...
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3answers
103 views

Power supply filter choke failure - how and why?

Trying to repair a non-working Fiber to Ethernet Converter. When connected to power, the unit made a hissing/sizzling/scratching sound and the all LEDs glowed dimly. I isolated a small surface-mount ...
2
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2answers
44 views

Meaning of infinite self inductance

I am reading about the characteristics of an ideal transformer and it is mentioned that self inductance of each coil is infinite. Could someone help me to understand the physics behind it? When self ...
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1answer
86 views

Maximum current to the circuit

The schematic of the wireless power transmitter is shown , The circuit works good. The inductor connected between circled nodes 1 and 1 is 24uH. (Note: both the inputs of FET are not shorted, they ...
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2answers
30 views

Can we make a simple wireless device by mutual induction phenomenon

I want to make a simple wireless device (radio?) that consists of only two copper coils where changing magnetic flux in primary coil causes a current flow in the secondary. I tried, once, with LEDs ...
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1answer
36 views

Why is inductance negative in this triphase mutual inductor?

Suppose I have a threephase circuit with a mutual inductor on the first and second phase (V2 and V3). One way of solving the circuit (ie finding the phase currents) would be the following: convert the ...
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1answer
38 views

Q-factor Inductor

The Q factor of an inductor is given by: Q=(2*pifL)/R Is this only the frequency dependent Rf? Or does it also include the series DC resistance?
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3answers
100 views

Complex impedance of a transformer

I consider only an ideal transformer here (no leakage etc.). Let L1 and L2 be the induction coefficients of the primary and secondary resp., and M be the mutual induction coefficient. Assume that the ...
5
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1answer
203 views

Why don't inductors simply “short”? [duplicate]

This might sound like a stupid question, maybe even so obvious that I can't find the answer anywhere else, but could someone please shed light on why inductors don't short out? With basically all of ...
3
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2answers
61 views

Solving circuit DEs: derivative of inductor current should be zero, but isn't

I am in the process of solving a DE for a circuit. So: the circuit starts with a voltage source of 5 VDC and is allowed to reach steady state. At time t = 0, the source is switched out for a 10 VDC ...
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1answer
37 views

Complex Power Phase

In a circuit with a voltage source in series with a capacitor, inductor, and resistor, will the complex power of the capacitor and inductor be in phase? In calculating Sc and Sl I see that the phase ...
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78 views

Direction of current in inductor

simulate this circuit – Schematic created using CircuitLab Can the Direction of current in an inductor in a closed circuit change instantaneously. The circuit is in steady state for ...
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2answers
58 views

Buck converter as a LED driver with NO LOAD

I am proceeding with a design of a LED driver using an LM3405. I don't read anything related to what happens when the load is not present, on the datasheet. As you may have already read, this is the ...
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2answers
49 views

Current step to LC circuit

An inductor is a device which adjusts its voltage to keep the same current flowing through. However, the current exponentially decays when there is no source any more. Similarly, a capacitor is a ...
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4answers
445 views

Adding a gap to a core for an inductor

I'm in the process of designing an inductor for a boost converter, and I'm having a hard time finding exactly what I need for this project. I have found a core size/shape that appears to work except I ...
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99 views

Booster Converter Question

So i've been learning about boost converters, and it makes sense. From what I understand in the schematic below when the switch closes the inductor receives a large amount of current (since we have no ...
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1answer
89 views

How to choose the correct inductor for my application

I am planning on using induction to power some game pieces in a project I am building. My plan is to use identical coils in board and piece, so they will be small (2" max diameter). My problem is ...
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3answers
72 views

Does mutual inductance change individual inductances?

If I have two inductors, with inductances \$L_1\$ and \$L_2\$. I put them really close to each other to make a transformer. Are their individual inductances still \$L_1\$ and \$L_2\$? Or has the ...
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2answers
136 views

Can inductors always be avoided in analogue filter design?

Inductors have always been described as big, bulky and extensive to me in text books. It seems that people don't like them. However, I have seen that inductors do appear in filter design due to ...
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2answers
37 views

RL and RC circuits with ideal diodes

Can you help me with this problem? what is V(t) before t=0 ? And also, any hints on how to solve the problem. This is not homework. I'm studying for a final exam and I'm really stuck. So if anyone ...
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3answers
58 views

Core loss appearing in buck converter ripple current

I have been told (and have also seen experimentally) that an inductor with a high core loss will introduce "glitches" to the ripple current in a switch mode power supply. I have tried researching ...
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2answers
66 views

What happens if I parallel two somewhat different size transformer primaries?

I have a small toroidal power transformer, perhaps 20VA, about 7cm outside diameter; core cross-sectional area is about \$16 \times 22 mm = 350 mm^2\$. I expect it's a wound silicon steel core. I got ...
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2answers
45 views

Voltage increase per cycle across capacitor for a boost converter

So I'm looking to make a high voltage capacitor charger using a boost converter and I'm wondering how much voltage the capacitor will increase per cycle of the boost converter. In reality, I would ...
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1answer
42 views

Calculating the time for current reducing to zero from a charged inductor in a series LC circuit

I'm wondering how you calculate the time taken for the current in a charged inductor to reduce to zero with the only current path being through a capacitor. I'm looking at this from the perspective of ...
3
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2answers
67 views

Can a “distributed gap” powdered-iron or ferrite toroidal core be used for a flyback converter's coupled inductor?

As just about all of us who deal with switching power supplies know, flyback converter designs use an air-gapped coupled inductor instead of a transformer. Typically, this gap is an explicit gap in ...
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1answer
58 views

Conformal Coating Affecting Inductor?

Question: Could conformal coating affect the properties of an inductor by adhering to its windings? Context and problem: I have a simple boost regulator circuit based around the TPS61230 IC. It ...
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4answers
54 views

how would inductor react if I inject current impulse into parallel LC tank?

What would happen if I inject current impulse into parallel LC tank? How would current flowing through inductor look like over time? If we look at the delta function in the S-domain (laplace ...
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2answers
57 views

Calculated result for inductance seems wrong?

I'm building an FM radio transmitter kit which includes an LC tank, where C is a tuner capacitor of ~30pF and the resonant frequency is ~100Mhz. The value of the PCB trace inductor, however, is not ...
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2answers
69 views

Parallel windings on a solenoid coil

Suppose I have a fixed voltage supply of 10 V and I need to get 20 amp-turns from my solenoid coil but my solenoid coil with 10 turns is 10 ohms, so I am getting 10V/10 ohms = 1A, 1A * 10 turns = 10 ...
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1answer
41 views

What is the back voltage generated by this inductor in this practice problem?

The circuit is in a steady state, and the switch is lifted at t=0. In (a), i calculated the current i and the voltage v at the instantaneous moment that the switch is lifted. The current is 2A and ...
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1answer
106 views

Old Inductor, replace with newer current-production?

I'm forced to rebuild a 'magnetic amplifier' circuit and PCB. This circuit was originally designed in 1968, and my PCB was assembled in 1972. It's all resistors and caps, with a few small transistors. ...
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1answer
145 views

Clamping Inductive Kickback in AC Circuits

I want to eliminate/clamp the inductive kickback that would result from turning off a large inductor, such as a relay or a transformer. In a DC circuit, I would use a diode to flywheel the current. ...
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42 views

Series inductance increasing piezo volume

Does an inductor in series with a piezo element increase its volume? If so, is it because of collapsing magnetic fields?
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49 views

A way to cancel/or harness back-emf?

In systems where there is back-emf induced to oppose the applied voltage, or to change it in cases of power converters, is there a direct way to cancel back-emf or harness it back? The simplest way ...
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2answers
96 views

What does “frequency test” mean with regards to inductors?

I am shopping on Digikey for an inductor for use in a radio application. The frequency range I am working in will be 200kHz - 900kHz. I noticed that there is a "frequency test" column where most of ...
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1answer
63 views

What is the gas valve section of this dryer schematic doing?

This Whirlpool gas dryer has an interesting collection of inductors (electromagnets operating valves) and a flame sensor that opens as soon as the ignitor gets hot enough to light a flame. What's ...
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75 views

Danger of Saturation of Primary Coil in a Flyback

I was reading a book, "switching power supply design - Abraham Pressman", specifically the section about flyback converters. One part I'm not quite sure I understand is where he says that the ...
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2answers
57 views

Theoretically determining Q for an inductor

I've recently been looking into passive filter design a little more closely than my classes have gone into, so far as actual component selection and design are concerned. The biggest sticking point ...
1
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1answer
75 views

Can an inductor be substituted for a coil

I am designing this FM receiver circuit. I have a few questions related to the circuit. Buying coil in my locality is a little expensive. So would it be alright to substitute an inductor in its ...
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1answer
43 views

In which of the LCR circuit the charge will decay faster?

Our instructor gave this problem. Cc << C. At time t = 0, the capacitor C has charge Q. In which circuit the charge Q will decay faster. Its answer is Charge Q decays faster in (A). ...
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41 views

Low-Frequency Magnetic Transmitter

I want to design a magnetic transmitter to detect a device which will be underground (1m to 7m) from surface, so I started to look at a solution and I find that a magnetic transmitter will work ...
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3answers
126 views

Non-linear scale of ammeter? [closed]

Recently some one asked me 'Why ammeter (based on moving coil principle) has a non-linear scale?' In multimeters (not based on moving coil principle) which we uses in digital lab, I didn't found any ...