Questions tagged [resonance]
For questions about resonance, the phenomenon in which the amplitude of an electrical circuit's output increases when the frequency of its input is equal to or near the circuit's natural frequency. Consider also using the "frequency-response" tag.
475 questions
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For a series RLC circuit, does the stored energy definition of the Q-factor give EXACTLY one over the fractional bandwidth?
I have read in several sources that for a resonator the stored energy definition of the Q-factor is "approximately" the reciprocal of the fractional bandwidth (with negligible error for Q ...
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What is the best way to multiplex 64 coils?
I'm trying to make a digital chessboard. The design consists of 64 coils, one under each square. A microcontroller's PWM sweeps the frequency over a given range, such as 50 kHz to 350 kHz. The signal ...
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How to deal with low values of coupling coefficient in resonant circuits?
Im not a eletrical expert, so bear with me. Im trying to simulate a LC circuit coupled with a RL circuit, sweeping the frequency from 0 to a arbitrary number and observe the system's response when the ...
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Where can I observe the high voltage generated in a tank circuit?
I am trying to learn about resonance in AC circuits and, in reading about them, one thing that made sense to me was the concept of a tank circuit. One should be able to input little bits of energy ...
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How does voltage increase due to oscillation in resonant circuit?
I am new to resonant circuits or LLC circuit concept. What I understand from information acquired from the internet resources and ChatGPT, at resonant frequency, capacitive and inductive reactance are ...
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Nano VNA shows something that I don't understand
I have cable with connected 50 ohms resistance, the length is 54 cm. Why I have such a result?
Why is the first minimum on frequency 230 MHz, but lambda/2 = 65 cm?
If I connect 50 ohms resistance on ...
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Why is the amplitude of the output voltage affected by the resistance during resonance when LC is connected in parallel with a resistor in series
The following picture is the circuit I simulated.
My question is, through theoretical calculations, the resonant frequency of this circuit ...
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For a PFC Boost converter, how significant is front end EMI filter damping?
Power converters are said to have a negative dynamic input resistance as long as the control loop is active( ie, within the gain crossover frequnecy).
Since the voltage control loop of PFC converters ...
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SRF calculation of a capacitor with trace inductance [closed]
I've been reading a Texas Instruments guide on decoupling of Operational Amplifiers (freely available here). On page 10, an example is given on how even a 1.5 cm circuit trace changes the overall ...
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Any way to increase the exitation frequency of this circuit?
I am working on the following exitation circuit for a fluxgate sensor:
The exitation circuit's purpose is to drive the coil (inductor on schematic) deep into saturation in both positive and negative ...
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Parallel and series RLC circuits impedance
As a student who is now studying resonance circuits,
I wondered why at the resonance frequency, in a series connection, when the capacitor's reactance and the inductor's reactance are equal to each ...
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Peculiar pattern of errors in series RLC quality factor [closed]
I performed an experiment to study the behaviour of a series RLC circuit at and near the resonant frequency. I did it 3 times, with 100 Ω, 200 Ω and 300 Ω, with the same L and C values. For each case, ...
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Properties of coils used in a power transmitter and receiver
I am completely new to wireless power transfer. I need to model a wireless power transfer link with the help of a Bode 100.
This is the reference document given to me.
Before starting this, I would ...
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LTspice resonant circuit simulation: Output not building up as expected
What changes should I make to get the output buildup continuously in the simulation, until I get some warning, maybe "simulation out of bounds?"
What is this underlying frequency of around ...
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Why does the resonance peak dampen when an air cored coil is kept on a conducting material?
I was performing an experiment on an air cored coil, when I noticed that the resonance peak of the coil (Real(Z)) in air was sharp, but when kept on an SS316 plate, the peak dampened. When the coil ...
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What does resonance means in inductive coupling? [closed]
From what I understood: resonance helps achieve higher coupling coefficients in coils.
What does it mean and how is it achieved?
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Determining transformer equivalent circuit components
I have made a PCB based planar transformer with a turns-ratio of 8:6. I am considering the T-model as shown below:
In the T-model, Lp is the primary side leakage inductance, Ls' is the secondary side ...
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Are inductors in resonant circuits dangerous? They produce very high voltages
A simple series LC resonant circuit has theoretically infinite voltage in the middle between L and C, if we assume 0 ESR and exact resonant frequency:
\$V_{at LC junc} = V_{in} \frac{X_{C1}}{X_{C1}-...
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Will a circuit oscillate at all its resonance modes or only the most dominant one?
Will a circuit oscillate at all its resonance modes or only the most dominant one?
Consider an amplifier with a feedback loop that meets the Barkhausen criteria at multiple frequencies. Will it ...
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How can this Clapp JFET oscillate when its gate is tied to ground at the resonance frequency?
How does the circuit below oscillate? It seems to have |gain| < 1 at its oscillation frequency of 2.25 MHz, yet it oscillates there.
My analysis:
The DC path is through L4 only, allowing a bias ...
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Where is the phase shift on this oscillator?
I didn't think the oscillator below could work, but I built it, and it does:
I used 10 uH for the inductor, 2.7 nF for the capacitor, and got oscillations around 8 MHz.
The feedback loop is a series ...
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Can transceivers count to fifty resonators? [duplicate]
I asked a since-closed question yesterday about an alternative to RFID. I assumed the way to phrase the question was as the most general possible engineering problem. I infer that it is probably ...
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Does this op amp connected to an LC tank amplify its resonant frequency?
The circuit below has a resonant frequency at 159.155 kHz and should amplify it:
That's exactly what this sweep predicts:
But,even when setting V1 to 159.155 kHz the transient analysis shows no ...
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How to digitally detect resonance in induction heater circuit?
System description:
H-bridge network of IGBTs (inverter) is used to supply power to a parallel LC circuit connected through matching inductor. It is desired to drive the parallel LC circuit in ...
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Varactor diode simulation behaving opposite than expected
I've been trying to learn about resonance circuits and filters and so forth, intending to try to build some kind of tunable filter or something.
I'm running some simulations in KiCAD to help confirm/...
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Identify values for these resonators
I need some help to identify the values of these resonators. Anyone here have experience with such components?
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Regarding the equation derivations of the resonant state of an asynchronous buck converter observing zero voltage switching
I'm currently reading this article of Bill Andreycak to understand the mathematics behind zero voltage switching: https://www.ti.com/lit/an/slua159/slua159.pdf?ts=1710666811170&ref_url=https%253A%...
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Current/Voltage phase shift issue with low/high capacitor capacitance
How to make voltage/current 90 degree phase shift properly?
In my PWM->sine "converter" the current/voltage phase is shifted 90 degree only with low value capacitor (10 uF), but no shift ...
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Power stage for driving a 100W piezo in resonance [closed]
I'm trying to design a power stage for driving a piezo transducer. It has resonance at about 1 MHz. My system has a DC voltage of 24V. The circuit will be locking frequency based on phase of voltage ...
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Do you know about topologies that look like this?
I'm working on a new topology.
I looked it up myself, and it says "3-level boost converter" has a low inductor.
Is this right? How do I search it?
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Ironing out a design for resonant inductive coupling on 13A. Would I be better off with MHz or GHz for efficient power transfer?
I am having a go at designing an extension cord that uses resonant inductive coupling. My knowledge lacks in this area, so I'm going back and forth via online research & chatgpt 3.5.
From what I ...
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Given that \$Q = {R} {\sqrt{L/C}}\$, why not maximise Q by setting L huge and C tiny?
For the tank circuit below, the resonant frequency is f0=10kHz, where:
$$
f0=1/(2 \pi \sqrt{L_1 C_1}).
$$
Assuming R=1 ohm, and given that [correction thanks to @Franc]
$$
Q_1 = \frac{R} {\sqrt{L_1/...
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Brushless DC motor stalls at startup
I have two small fans with brushless 12 V DC motors connected in series. Each motor has a flyback diode. Also in series is a small resistor to bring the voltage down slightly from 28 V, which is the ...
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4 MHz RF-receiver not working
I have been trying to make a 4 MHz receiver, to receive a ASK/OOK modulated signal but it never really works. I have my suspicions that it's the LC tank that is not tuned correctly, I am quite new to ...
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Multiple resonance frequencies of common-mode choke
In the datasheet of the CMC (common-mode choke) below (Würth Elektronik 744830017132), the impendence vs frequency graph has multiple peaks (resonances) which I marked.
The first one is the Self ...
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Please offer comments, critique on self-resonating invented buck joule thief converter for third world use [closed]
Even though I'm not an EE, I have simulated the Joule Thief to death in LTSpice, but I have not yet made a prototype of this circuit. I have a friend who is an EE who won a contract to light some ...
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How is a resonant bandpass filter similar/different from a damped mass-spring oscillator? They seem to behave different in testing
Background
I am using resonant bandpass filters as musical oscillators. One can excite an array of them at harmonic frequencies and given Q values for a note by, for example, running a burst of noise ...
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External circuit to increase the series capacitance of a resonant circuit
I am working with a long-range reader and antenna coil for a low frequency (135 kHz) RFID application (please see the basic representation below.) The reader features some unknown source impedance, as ...
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LC Resonance with Inductor with Solid Metal core
Consider inductor with air gap and solid metal core made from material with relative magnetic permeability 1 regardless of temperature (such as copper or aluminium).
There is Air gap between coil and ...
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How can I drive an LC tank with a transistor?
I've been exploring the idea of making an induction heater.
Mostly I see people using the ZVS circuit to do it, but I would like to get an understanding as to how you would do it if you had an ADC and ...
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Why does resonance cause unique behavior of S-param in two-port system?
In a two-port system where a square signal passes through a via we can get a HIGH Q resonance structure which could ruin our S21.
I know that resonance is a standing half-wave pattern, so what what ...
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Why does S-param resonance behavior differ from formula?
The general formula for resonance is \$w_0=\frac{1}{LC}\$ . A simulation was built with such inductor and capacitor so the resonance will be at 1GHZ.However as you can see in the result ,the plot ...
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Why is it difficult to write the close loop transfer function of a frequency modulated DC-DC converter (for eg - LLC converter)?
I know how to derive and write the transfer function of duty cycle/pulse width modulated DC-DC converter. We need to linearize the switches and then write KVL/KCL equations and then derive the output ...
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Why is an LLC converter designed to operate in the ZVS region? how does the Resonance in the LLC circuit contribute to low "MOSFET losses"?
For the first question I understand that operating in the ZCS region can result in shoot through but why does that happen?
I understand that an LLC converter uses the leakage inductance of the ...
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What is the difference between natural frequencies and resonance frequency in second order circuits?
The following circuit:
can be described by:
$$\frac{d^2v_c}{dt^2} + \frac{R}{L}\frac{dv_c}{dt} + \frac{1}{LC}v_c = \frac{R}{LC}i_S$$
From there, it's clear that the undamped natural frequency, or ...
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LC Parallel resonance induction heater
Consider parallel LC resonance induction circuit with solid iron workpiece, inserted in the inductor. Is it possible to obtain more heat power output from the heated solid iron workpiece in the ...
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Power supply coupling of inductive resonant sensors
I'm working on an array of sensors based on Peltz Oscillators connected to a micro to detect objects based on shifts in resonant frequency when a target object gets close to the inductor. In isolation,...
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Resonant Coupling for Optimal Power Transfer
I am trying to read the following paper:
B. L. Cannon, J. F. Hoburg, D. D. Stancil and S. C. Goldstein, "Magnetic Resonant Coupling As a Potential Means for Wireless Power Transfer to Multiple ...
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How can I find the Q factor an LC circuit using LTspice?
I've built a very simple LC circuit which models a air core copper wire loop antenna. I got the circuit resonate at around my desired frequency i.e., 13.56 Mhz. Now I want to calculate the Q factor ...
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How to choose power rating of a damping resistor for an LC filter? [closed]
I am trying to put power filter for an SMD oscillator (https://www.renesas.com/us/en/document/apn/863-power-filter-recommendations-smd-oscillators). One concern is the LC resonance. There are ...
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