Questions tagged [harmonics]
Questions related to frequencies that are generated by mixing other fundamental frequencies.
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How to enrich harmonics in audio?
I'm designing a guitar pedal to boost harmonics in the signal here: Falstad Link
I'm wondering if there are ways to boost harmonics that don't clip the signal, as well as any adjustments I should make ...
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How to add harmonic distortions to guitar amp? [closed]
I was reading about the carver challenge,(https://www.stereophile.com/content/carver-challenge) and read that he had added a series of potentiometers to one of his amps that had allowed him to ...
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Harmonic n intensity varies greatly between phase - Is it important?
I tried to find explanation over this - maybe my terminology is wrong, couldn't find anything.
I wondered if it's important the for 3rd harmonic, intensity of voltage of Phase A is almost half the one ...
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Signal Integrity in electronic systems
When I went through EMC testing of some electronic boards, I observed that the frequencies of the EM waves generated by the boards are at the fundamental frequency with multiples of some whole number. ...
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Fundamental vs true RMS values - Can the fundamental be higher than true RMS
Here is a practical situation: We are measuring harmonics with a Class-A PQ device. At certain times we have the fundamental values of current higher than the true RMS values. I would like to know if ...
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Are voltage harmonics critical in the electric grid?
I'm a student of Politecnico di Milano and today my prof during the lesson told me that it's important to limit current harmonics into the grid and not voltage harmonics because these last do not ...
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Fourier transform and what it represents
Suppose we have a sine voltage supplied to a resistive load. When I perform a Fourier transform to this signal in the frequency domain what do I get? All values of g(a) will be 0 except for the ...
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Is it viable to short pitch different windings by different degrees of short pitching in the same synchronous generator?
In the design of a synchronous generator one can chose to eliminate or reduce harmonics at the expense of emf.
The pitch factor \$K_p = \cos(\alpha/2)\$, which is always less than or equal to 1, ...
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Reason for frequency steps shown in Simulink FFT analysis tool
While using the FFT in Simulink tool, I have observed that if more number of cycles are selected then frequency steps in which harmonics percentage is shown is also divided accordingly.
For example:
...
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How to use DFT to find harmonic content of an AC waveform?
I am kind of new to this coding and simulation environment. For my first project I need to take samples of current signals from power line and find out the harmonic contents using DFT. I haven't done ...
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Triplen harmonics not appearing in the output of DigSilent PowerFactory 2021
I am running simulations for harmonics resulting from the connection of an offshore wind farm to the main grid on DigSilent PowerFactory 2021 SP3. I am using a script to run multiple scenarios and ...
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Harmonics in neutral conductor
If he multiplied the 10 A by 3 this means each phase has 10 A of harmonics. So, shouldn't they cancel out at the neutral just like the rated frequency currents?
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Inverter Fourier analysis
I have an inverter circuit like below:
I will use bipolar control method to produce sine wave. Our teacher said us prove basic harmonic of inverter is equal to multiplying of modulation index and Vd, ...
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Do energy storage systems really improve the quality of the energy?
I know that an ESS (energy storage system) improve power quality issues avoiding interruptions, controlling the voltage and the frequency, injecting reactive power into the grid thanks to the ...
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I’m trying to manipulate the harmonics of a square wave, and my circuit is not working
I am trying to build a circuit that can boost or cut multiple harmonics of a square wave. I am trying to use a graphic equalizer gyrator circuit. I have had very little luck with this. Any suggestions ...
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What's wrong with my experiment to observe harmonics caused by receiver saturation and non-linear behavior?
I've been trying to devise an experiment to produce a third order harmonic in radio receiver that's been saturated, but I'm not seeing the expected results.
My understanding of the theory is that when ...
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Adding harmonics to the square wave means
I have generated two imperfect square waves by:
Adding fundamental frequency with 10 odd harmonics.
Adding fundamental with 20 odd harmonics.
What difference should I observe between two imperfect ...
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Harmonics produced by LCC converters
Considering an LCC HVDC system and that the flow of power is ALWAYS in the direction shown in the figure.
I know that converters in general produce harmonics.
My questions are:
Does this HVDC system ...
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Reduction of the harmonic currents in LCC HVDC systems
Why there is a reduction of the harmonic currents in the AC side in an LCC HVDC system?
Here is represented the AC current in yellow, in red the DC voltage and the sinusoidal waves are the AC ...
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Transformer Harmonics
A typical installation is
Load - 400 V net - Transformer 1:25 - 10 kV net
If the load is for example a SPS, the 400 V net can contain harmonic currents and thus have a considerable THDi.
How can the ...
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Harmonics in transformers
could you explain what it is that causes harmonics in transformers?
I've read that these are the reasons, but it still doesn't give me a proper explanation.
Saturation of the core
Magnetizing current
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Harmonic Balance works, transient does not work!
I have an oscillator circuit and the harmonic balance simulation shows there is oscillation in Vout:
However, when I run a transient analysis, the results are totally different and show there is no ...
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Can AC harmonic quantities be expressed as a sum of phasors of different frequencies without confusion?
https://www.electronics-tutorials.ws/accircuits/harmonics.html
The problem with AC harmonics is that each term has a different frequency, being a integer factor of the first frequency. I was wondering ...
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Why does wound rotor IM have the belt leakage but the squirrel cage rotor does not?
According to the description on page 159 of Prof. Lipo's book "Introduction to the AC Machine design":
It is important to mention that the harmonic leakage is important only for wound rotor ...
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Ceramic resonator changes and maintains frequency when touched
I'm experiencing a weird phenomenon with a ceramic resonator test circuit, where the frequency of its output can be changed by touching the circuit with my finger. The circuit would maintain this ...
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Switched capacitor sample and hold circuit as as mixer
I am trying to find out how important the "hold " level in a sample and hold down-conversion mixer is.
If the level is decreased, will it lead to any loss?
Out of these three subfigures, ...
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Harmonic analysis of an electrical circuit
I am having troubles trying to figure this out.
I have a complicated electrical circuit and I would like to compute the spectrum of some voltages of interest. Below is an example of what I want to do ...
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Does imposing an odd initial condition reduce spurs in MASH Delta-Sigma Modulators that has second order stages?
I've been reading about how fractional spurs can be reduced in a Digital MASH Delta Sigma Modulator (especially for application with a fractional-N PLL) by having the initial condition of the first ...
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Are harmonics always the peaks in the frequency response plot?
I would like to implement a certain type of audio alarm with 1 fundamental frequency and 4 harmonics.
The example frequency response of a qualified alarm on the spectrum analyzer is shown in the ...
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THD calculated with amplitude instead of RMS
I have a digitized sinewave, and want to determine the THD of this waveform.
This is the equation I am familiar with for calculating THD:
$$
THD=\frac{\sqrt{\sum_{n=2}^{\infty}V_{n_{rms}}^2}}{V_{fund_{...
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Single-phase thyristor full bridge rectifier vs three-phase thyristor full bridge rectifier
For Single-phase thyristor full bridge rectifier compared to a three-phase thyristor full bridge rectifier, with regards the input current harmonics, does the three- phase rectifier have an advantage ...
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What is the physical meaning of reactive power in non-sinusoidal steady-state (with harmonics)?
In sinusoidal steady-state (linear loads, no harmonics), I understand what is reactive power \$Q = V_{\text{rms}} I_{\text{rms}} \sin{(\theta)}\$ where \$\theta = \theta_v - \theta_i\$: its absolute ...
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If interharmonics are defined for periodic signals, aren't interharmonics misleading?
Before explaining my question, I'm going to assume that 1) interharmonics, just like harmonics, are sinusoids; and 2) to analytically represent the interharmonics of a signal, we sum them to the ...
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When a signal has an interharmonic, is the signal periodic or non-periodic?
I have some questions regarding interharmonics. What I'm going to do is first ask just a few, and then as people answer them I would expand this post or create a new question.
Harmonics are sinusoids ...
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Why the power line interference harmonics appear gaussian?
I have a recorded signal from a data acquisition system.
I am getting this noise in my signal:
The picture shows the FFT of the signal. I checked the frequencies of the noise and they are 50 Hz apart ...
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Validity of superposition when summing powers from each harmonic
In Boylestad's Introductory Circuit Analysis 13th edition page 1176, there's an example about working out the total power dissipated by a circuit fed a nonsinusoidal signal. The signal is decomposed ...
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Oscillator circuit using comparator and opamps
All opamps are ideal and Rx = 2R in the figure. The comparator is a nonlinear block which operates as follows: if its input Va < 0, its output is +1V. If Va > 0, its output is -1V. To simplify ...
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how to tune wave to obtain a specific harmonic seriers
I wanted to know what is the relationship between a square wave and its harmonics, in other words can i change a square wave features (frequency, duty cycle etc) to obtained a desired fundamental ...
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Harmonic voltage source, how to calculate it
I have this scheme.
I have all the parameters:
L1=110 uH
C1=160 nF
C2=5 nF
Rt=1.2 kΩ
ω1=45290 rad/s
ω2=162089 rad/s
ω3=238366 rad/s
ω4=276982 rad/s
But I dont understand how to calculate the ...
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Is my thinking right for the simple harmonic circuit
If this is a simple harmonic circuit, then what is the \$X_C\$?
I know harmonic circuit means that there is no value in the imaginary part of the impendence or admittance, that is, \$Z_{th}=R+0j\$ or ...
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Why harmonic distortion and not at other frequencies?
Despite searching I can't seem to find the answer to this. In understanding harmonic distortion, one piece of the puzzle that is missing for me is:
- why does the distortion manifest at harmonic ...
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Relationship between harmonic's amplitude and square wave's Tr and Pw
I started reading this TI guide on high speed layout guidelines and had some question on the theory of clock signals (pages 2 and 3).
From the image below it's clear that the amplitude of the first ...
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Aperiod vs Period waveform Fourier Transform: How does nature understand which is the case?
Today I reviewed the theory behind the Fourier Transform, and I asked myself a question that I couldn't answer to in the process.
Theory: A periodic waveform has a Fourier series which can be seen ...
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Why exactly does peaking of magnetization current occur in a transformer?
Initially assuming that the input current is sinusoidal.
In a practical transformer, flux \$\phi\$ produced in the primary is not linearly proportional to the current \$I\$ through it. Due to ...
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How Power measured by Meters is affected by Harmonics?
I want to know how energy meters (Electro-static or electronic) measure Energy (let's assume power, ignore time) when there are harmonics present.
I know what are harmonics, how are they generated ...
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Why is total harmonic distortion defined in the following manner?
So the total harmonic distortion is defined as
$$THD = \sqrt{\frac{V_{2}^2 + V_{3}^2 + V_{4}^2...+V_{n}^2}{V_{1}^2}}$$
which means Total harmonic distortion is defined as the square root of the ...
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Where should power factor correction and active harmonic filter connected?
After mains electricity meter, there is an isolation transformer (delta to star) and all load is connected to the secondary of the isolation transformer.
We plan to install a power factor correction ...
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Total Harmonics Distortion and DFT
I am trying to understand a design that would enable us to measure/determine the Total Harmonic Distortion.
Few key points:
The system is micrconcontroller (TI, C2000, dual-CPU) driven electronics
...
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RFI filter modeling in LTspice w/ triac
I have a few questions about modeling an RFI filter in LTspice with a triac-based dimmer circuit. I'm referencing the circuit described in Figure 11 in Triac Principles and Circuits -- Part 2 (Nuts &...
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approximation of a digital signal using the harmonic
I'm new to EE, still struggling in understanding some basic concepts. I'm reading a book which says about approximation:
To make the shape of the analog signal look more like that of a digital signal,...
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