# Questions tagged [non-linear]

The tag has no usage guidance.

82 questions
Filter by
Sorted by
Tagged with
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 ...
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?
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 ...
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 ...
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 ...
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 ...
55 views

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 ...
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 ...
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 ...
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 ...
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=...
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 ...
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 ...
50 views

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 ...
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 ...
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....