Questions tagged [non-linear]
The non-linear tag has no usage guidance.
82
questions
-1
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2answers
74 views
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 ...
0
votes
1answer
39 views
Difference between THD equation and design circuit current
Why does the summation of design circuit current equation (Ib) start with 1 while for calculating THD the summation starts with 2?
-1
votes
1answer
43 views
Colpitts oscillator bypass capacitors importance
A Colpitts oscillator makes use of the common emitter configuration, and the
indicated amplifier configuration is known to be a linear circuit. How come do we call the
stated oscillator a nonlinear ...
2
votes
1answer
46 views
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 ...
0
votes
0answers
18 views
Linearization of nonlinear plant with system identification in Matlab
I hope this question fits in here and there is someone who can maybe help me.
I am new to control theory and I have a very complex Simulink model which is nonlinear. I want to have a linear ...
4
votes
1answer
113 views
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 ...
2
votes
2answers
55 views
Temperature sensing with ADS1115
I am using an ADS1115 as an analog to digital converter to measure temperature. I am using an RTD100 temperature sensor to measure a temperature range of -40 to 150 degree celsius but the resistance ...
0
votes
1answer
63 views
Does a wide-band, high-current, inline ammeter circuit already exist?
I have an application where I would like to measure currents up to 1000 A, inline, but am also interested in using the same circuit for a low current part of the cycle. The thought is that if I can ...
2
votes
1answer
81 views
Variable-Gap Capacitors in LTSpice
I have seen several blog posts that discuss the concept of a nonlinear capacitor (or inductor) here, here, and here. Thanks to a concerned citizen for the references.
I'm still struggling with the ...
0
votes
1answer
107 views
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 ...
0
votes
2answers
59 views
distance between linear and non-linear function of op-amp system
I have a circuit which I have taken a picture of as you can see, in which i have values of
$$R1=1k\Omega,R2=10k\Omega,R3=10k\Omega.R4=10k\Omega,R5=20k\Omega$$
and sine input signal with off-set value=...
0
votes
2answers
60 views
Why is the Hybrid-PI model like that?
The BJT and MOSFET can be modeled using the Hybrid-pi model. I only know that the transistor can be modeled with linear elements like that, but I don't know why.
There are a lot of things that confuse ...
0
votes
0answers
70 views
DAC “aliasing” of harmonics
While reading articles and application notes regarding DACs and their output spectrum, I stumbled across aliasing of higher harmonics to the first Nyquist band. For example, when generating a single ...
1
vote
1answer
50 views
Linearization of nonlinear system
I have a nonlinear system described by:
$$\begin{align}
V\,\dot x_1 &= Q_1 C_1 - (Q_1+u)x_1 \\
V\,\dot x_2 &= C_2\,u -(Q_1+u)x_2 \\
y &= -\frac{\log{\left[(x_1-x_2)+|x_1-x_2|+4K\right]}...
1
vote
3answers
79 views
what is the load line and operating point used for in practical?
I have a hard time understanding what an operating point and load line represent and why do we need them at all.
After reading some wikibedia,
What I got is this load line represent response of the ...
-2
votes
3answers
85 views
1
vote
1answer
52 views
Linearization of IR sensor GP2Y0A21YK
How do I linearize the graph analog output voltage against distance for IR sensor [GP2Y0A21YK][1]?
This is the non- linear graph, I’m not sure how to make it linear?
[1]: https://media.digikey.com/...
1
vote
3answers
325 views
Stuck on a simple piecewise linear element problem
See the schematic of interest on a picture. \$V_S = 5 \,\rm{V}\$, \$R_S = 4700 \,\Omega\$, \$R_P = 5800 \,\Omega\$. The cucumber-shaped element is a nonlinear element. The only thing we know about it ...
0
votes
1answer
57 views
How can the maximum average power transfer be negative in a power delivery circuit?
It is possible that the Thevenin resistance \$R_{Th}\$ of a circuit is negative. This occurs in non-linear circuits. Likewise, in AC circuits, the real part of \$Z_{Th}\$ can be negative.
For AC ...
1
vote
1answer
53 views
Non linear DC voltage conditioning
I do not want to use any adc or dac. I want to see if this is possible by pure analog circuit. Any google links or book names are welcome. From 0 to 1000mV output should be 0 to 100mV. Then from ...
0
votes
0answers
32 views
How should I model differential non linearity (DNL) of a DAC?
I have very little experience with electronic instrumentation, and I'm learning about INL/DNL.
I'm looking at the specifications for a DAC, and the sheet claims a guaranteed DNL of -1 to 1 LSB. ...
2
votes
1answer
173 views
Linearizing hall effect sensors outputs
I'm trying to find a robust solution to linearize four hall effect sensors outout to obtain a signal that I can use in a PID control scheme.
The output data is collect via 4 ADC channels on an ...
6
votes
3answers
289 views
How can I realize this nonlinear resistor?
I want to know if it's possible to realize a circuit described by the equation
$$I = \sin(w V)$$
where \$I\$ is the current, \$V\$ the potential and \$w\$ a variable which characterizes the single ...
2
votes
2answers
354 views
Non-linear Inductor LTSpice
I am trying to implement a non-linear inductor in LTSpice and to get it to saturate.
I am using the following directive between N1 and N2 as advised in the help files:
L1 N1 N2 Hc=12 Br=0.2 Bs=0.4 A=...
0
votes
0answers
278 views
How to make a non-linear potmeter more linear
I have an "Expression pedal" that worked fine on my old keyboard (Gem WX2+) but works almost like a digital switch on my new keyboard (Roland VR-09).
The recommended expression pedal is a Roland EV-5 ...
0
votes
1answer
42 views
Normalizing a nonlinear plant in system identification in control
I have calculated the "active power" and the "the reactive" power of a system in dq axis in nonlinear form and I am doing system identification on this "nonlinear" plant as a MIMO system.
The problem ...
1
vote
3answers
122 views
Performing small signal ac analysis with non-linear components
I have written a circuit simulator that uses Kirchoff's voltage and current laws to solve linear circuits containing capacitors, resistors, inductors and op-amps (where the op-amps are assumed to be ...
1
vote
3answers
145 views
Bandwidth and stability of nonlinear circuit
I'm designing an antilog amplifier which produces an exponential output (0.4 mV to 4 V) for a 50 Hz sawtooth input waveform (4 mV to 4 V ramp). If this were a linear circuit, I could determine the ...
0
votes
1answer
217 views
Transfer function_Approximation of second order system for a linear actuator
I am trying to approximate a transfer function of a system. The system is a linear actuator, connected to a feedback potentiometer. The actuator has a mass on it. The following figure is a step ...
0
votes
1answer
159 views
How to plot response of a non-linear state space model in Simulink?
I am trying to plot a non-linear model in order to compare it with it's linearized counterpart.
I am following this paper Nonlinear Model & Controller Design for Magnetic Levitation System and ...
1
vote
0answers
67 views
2 tone test with RF mixer
I am designing a system that uses RF to probe the nonlinearity of a target. It works as follows.
Transmitter sends out 2 RF frequencies, such as 900 and 910MHz.
The target/reflector has a ...
0
votes
1answer
259 views
DC motor driver response [closed]
I have some trouble about the response of the L298N DC motor driver.
After some experiments, I have noticed that the output response of the L298N isn't linear.
In particular, if i give a ramp input ...
1
vote
0answers
40 views
Analyzing a non linear circuit with two sources [duplicate]
I want to analyze this circuit. V1 is a) +15V b) +10V c) -5V
I need V2, V3, I1, I2, I3
Uz=6,8V
UF=0,7V
And I hate to say this, but I'm absolutely lacking any approach. I don't know how to manage V1....
1
vote
1answer
108 views
Problems with analyzing a simple, non linear circuit
I have some problems with analyzing this pretty simple circuit (or more precisely with understanding the solution):
The task is to find the characteristic curve for $$|U_E| \le 5V$$
My first ...
0
votes
0answers
58 views
Is the V_t in this document regular Thermal voltage?
I have been looking at this short document.
https://pdfs.semanticscholar.org/c490/4c04a7be1d675e360409178da71a1253f6d8.pdf
It uses V_t and defines it as thermal voltage of a transistor.
It does not ...
0
votes
1answer
209 views
Solution for a set of non-linear equations
I am trying to solve the following equations for \$\delta\$ and \$K\$.
I have tried Matlab function fsolve, but unsuccessfully. I also tried Wolfram Alpha and, ...
7
votes
1answer
565 views
Simulating Chua's circuit in LTspice with a saturating transformer-based nonlinear resistor
Chua's circuit is one of the simplest circuits known to exhibit chaotic behavior. It consists of resistors, capacitors, an inductor, and an active nonlinear resistor. One implementation of this ...
6
votes
2answers
866 views
If there exists a cascade of op amps, does the previous op amp's slew rate affect the later op amp's slew rates?
All op amps used are the same Texas Instrument LM348n. The datasheet says the op amp has a nominal slew rate of 0.5 V/µs, but gives no tolerance.
I have a square signal with an amplitude of 500 mV ...
0
votes
1answer
89 views
Is the gain from IIP3 curves wrong?
Suppose I have an unknown system and I would like to know its linearity.
I am confused by the proper measurement of the IIP3. The gain is defined as "total output power" divided by "total input power"...
2
votes
2answers
397 views
Why linearise around an equilibrium point?
In the control theory dealt in class I was taught to always linearise a nonlinear system around an equilibrium point, i.e., where $$\dot x = 0$$
However, linearization is a Taylor series expansion, ...
0
votes
1answer
938 views
Linear and non linear phase FIR filter
I am a confused about linear and non linear fir filter.
I have this depiction of the solution space for linear-phase and
nonlinear-phase FIR filters for a given set of specifications.
Region 1 ...
0
votes
0answers
185 views
Timestep error for Logistic Map in LTSPICE
I am building a logistic map circuit in LTSPICE. So far, I've prepared this:
The factor of 25 after the second AD633 is for increasing the scope of the parameter values. However, this circuit always ...
1
vote
1answer
90 views
What are the mechanism and effects of non-linearity in an attenuating barrier in the presence of a high-strength EM field?
It's my understanding that in electromagnetics, if an attenuating device is functioning linearly, it means that 1) input and output signal strengths are proportional; and 2) input f = output f. How ...
-2
votes
1answer
235 views
Linear and non-linear attenuator
[edit 3/2/18] There are problems with the title and wording of this question. I would edit, but to do so would alter the relationship between the question and the answer that I accepted. So, I have re-...
2
votes
0answers
82 views
tracking error state space, linear control example
I am trying to understand a detail from an example, from the control textbook Slotine and Li (1991) "Applied Nonlinear Control", Prentice-Hall, Example 6.4, pag. 220. A linear system is given:
$$\...
0
votes
2answers
243 views
Overshoot Before Transition
First of all, a little bit of context: I'm designing a single-supply Howland current source using the OPA357 (rail-to-rail 200MHz OPAMP) to delivery 100uA of AC current up to 1MHz. In one of my ...
0
votes
2answers
120 views
Photodiode + Op-Amp Acting Nonlinearly
I've built a laser power meter based on a photodiode (likely a ThorLabs FDS10X10), a simple op-amp circuit (op-amp is TLV2462, max 12V), and a microcontroller+screen:
Internally, I've built the ...
1
vote
0answers
64 views
Nonlinear system general representation
I am fairly new with non linear systems. I understand that a general representation of a nonlinear system is:
$$
\dot{x} = f(x) + g(x)\cdot u
$$
where \$x\$ is the state variable, and \$u\$ the input....
-3
votes
1answer
120 views
Good book on system identification for non-linear systems? [closed]
Can anyone suggest a good book that describes how to experimentally identify and describe non-linear behavior in real world systems? I have had good success analyzing systems using linear methods such ...
0
votes
1answer
36 views
Highly integrated RF front-end chipset RFX8055 issues
In this datasheet of RFX8055 (CMOS 5GHz WLAN 802.11a/n/ac RFeIC WITH PA, LNA, AND SPDT switch), they mention "5GHz Power Amplifier with Low-Pass Harmonic Filter".
If this filter is meant for ...
