Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [transfer-function]

Anything related to transfer functions, i.e. those complex-valued functions of a complex variable used to model mathematically the I/O relationship of linear time-invariant initially-at-rest system using Laplace transform.

1
vote
3answers
68 views

How to find a number a such that an input 10e^-at to a transfer function does not have a Ke^-(at) term in the output

I have a transfer function, \$H(s) = \frac{-16(s+4)(s-1) }{ (s^2+16)(s+2)}\$. The impulse response is \$-16*(-3/10 * e^{-2t} + \frac{13}{10} cos(4t) + \frac{1}{10}sin(4t))u(t)\$. I am supposed to ...
1
vote
1answer
78 views

Creating smooth PWM response

By using PWM I have converted some signal to pulses and inserted it into transfer function of 2/(0.01*s+1) I then compared between the result of the original ...
0
votes
2answers
50 views

Gain of Inverting Active Bandpass Filter

For the filter below I calculate the transfer function $$H(j \omega) = -\frac{R_2C_1 j \omega}{(1+C_1R_1 j \omega)(1+C_2R_2 j \omega)} $$ and thus calculate the gain $$A= \sqrt{ H(j \omega_o) H(- ...
-1
votes
0answers
60 views

Discharging second order RC Filter

I need to find an equation which describes voltage on Capacitor C2 over time. In time < 0, switch S1 is closed. In time => 0, switch S1 is open. The voltage source is DC and its value is V0. ...
0
votes
2answers
93 views

Second Order Passive RC Low Pass Filter Doesn't Have -6dB at cutoff Frequency in LTSpice

For Second-Order RC filter the cutoff frequency is: $$fc = \frac{1}{2\pi \sqrt {R_1C_1R_2C_2}}$$ I have taken R1 = R2 = R = 1K Ohm and C1 = C2 = C= 0.1591 micro Farad. So the cutoff frequency comes ...
-2
votes
0answers
20 views

Problem calculating gain with reference voltage

I cannot get the transfer function as I'm not able to get Vout/Vin with reference voltage different from zero. Ia there a way to obtain the t.f? PD: Im sorry about the rotated images.
0
votes
1answer
48 views

Calculating the transfer function of this op-amp circuit

The first op-amp is a differential, second one is a follower and third one is a second order low pass filter. I've been struggling with the low pass and the final output of the circuit and I am not ...
0
votes
4answers
89 views

Is it possible to switch an electrical machine several times from motor to generator and vice-versa, within one revolution of its rotor?

I would like to find out how quickly and frequently a reversible electrical machine (EM) can be made to switch functions from a motor to generator and vice-versa - and what are the parameters of the ...
0
votes
0answers
54 views

transfer function of RC in parallel

I was looking at RC in parallel (at the bottom of the page at the link) to understand the transfer function \$\frac{V_{out}}{I_{in}} = \frac{R}{1+SRC}\$, in the case that the input is a constant ...
0
votes
1answer
57 views

Cascaded Transfer Function Method for Frequency Response

Multiplying the transfer functions of multiple cascaded circuit fragments to get the frequency response of the system doesn’t work because of loading between stages. However, I came across the ...
3
votes
1answer
133 views

Degenerate circuit concept and its theoretical and practical implications

I came across with the term "degenerate circuit" when I was studying solving linear differential equations with Laplace transform. I have learned that a system is called degenerate when the ...
1
vote
2answers
113 views

How to define a transfer function for a given system?

I just finished reading this paper, on how to "draw" Bode plot for a given transfer function. After done reading I realized that it would be pointless to learn this stuff, if I wouldn't know how to ...
0
votes
1answer
53 views

Are these equations correct? (transfer function)

I have a given transfer function \$ |H| = \frac{R_2}{\sqrt{R_1^2+\frac{1}{(\omega c)^2}}} \$ where \$ c = 1\mathrm{\mu F} \$ and \$ R_1,R_2 \$ are unknown. I know that \$ |H(j\omega_c)| = 50.1 \$ ...
2
votes
0answers
37 views

Low entropy transfer function, output impedance

I am trying to understand and apply the concept of low entropy transfer functions as outlined by C.Basso and equally stated by a couple of people here. As an example I wanted to work through an L-C ...
0
votes
0answers
47 views

Issues to create a current control transfer function for a DCDC Converter

I'm trying to reproduce a work I've seen in an article, but I'm encountering some issues. I used the data provided and the transfer functions placed by the author, but I did not get the same result, ...
0
votes
0answers
53 views

How to get the transfer function of electrical network using nodal method

We have the following circuit: I am trying to get the transfer function using the Mesh Method. The first equation I've got is: (s+1) I1(s) - sI2(s) = Vi(s) The ...
0
votes
2answers
102 views

Transfer function of a bandpass

i was doing some homework and one thing I had to do was to derivate the transfer function of a given bandPass. I have done it myself but i dont know if it is correct nor if i followed the right path / ...
0
votes
0answers
35 views

How to get discrete state space equations from Laplace transfer function?

I had some trouble solving an exam problem which goes like this : Given a system transfer function H(s) = 9/(\$s^2 +9)\$ : 1) Find the discrete time state space equations 2) What is the conditions ...
-1
votes
1answer
44 views

Relation between dash pot and spring in forces when extracting a transfer function [closed]

If a spring load some energy and use it for opposing other forces, and a dash pot has a friction, physically the both shouldn't have the same force-displacement equation ? In most of dash pots, we ...
0
votes
1answer
50 views

Low Entropy derivation of Transfer Functions with OP AMPS

I was recently low entropy equations of passive filters, and came across the Extra Element Theorem and all of its uses. I was wondering if the there is something similar for OP AMP circuits/ Active ...
0
votes
2answers
56 views

Root locus, where do they leave the line parallel to imaginary axis

I know how to sketch by hand root locus of simpler systems. Consider the root locus which Matlab gives for: $$G(s) = \frac{1}{(s+4)(s+6)(s^2 + 10s + 100)}$$ I've marked the points of interest P1 and ...
0
votes
1answer
43 views

How to I go from generalized Transfer Function to generalized State Space, and back?

Question: How can I transform a generalized Transfer Function a generalized state space form (preferable with the First Companion Form), and back? For the sake of presenting an example, let us say ...
0
votes
1answer
93 views

Root locus for an open loop transfer function?

The function, rlocus(), in MATLAB is used for closed loop system roots for variation in gain K. However, I am curious if there is a similar function for variation ...
1
vote
2answers
67 views

Meaning of the “pole” of a transfer function with time delay

I learned in basic control theory that we can determine the stability of an LTI system by the signs of the real part of the poles of its transfer function \$H(s)=\frac{N(s)}{D(s)}\$. For a rational ...
1
vote
2answers
103 views

Transfer Function: Trying to understand the Laplace analysis of this circuit

I am trying to do the transfer function of this circuit and also trying to understand the frequency domain thing of the Laplace transform. I want to do a transfer function of VA/V1, considering B to ...
0
votes
1answer
44 views

gain of inverting op amp with resistor on input

I´m trying to figure out the transfer function of the attached op amp circuit. I came to the conclusion that v_out = - v_in as as the two resistors in the upper path are equally sized, and the non ...
-2
votes
1answer
82 views

What kind of software I can use to plot graphics like this? And how is this plotted? [closed]

I am trying to plot the transfer function of a circuit. What kind of software I can use to plot graphics like this, without using circuit simulation software? I would like to understand things ...
3
votes
1answer
70 views

PID tuning without plant model

My aim is to keep temperature constant at a certain place. I don't have a mathematical model of the plant. Currently, PID is used with some fixed Kp, Ki, and Kd, and I want to optimize these ...
1
vote
0answers
75 views

Phase Locked Loop Gain Design- FM Demodulation

Say I am trying to demodulate a message up to 25kHz in frequency, with a peak frequency deviation of 75kHz and a carrier of 1MHz, implying a 200kHz bandwidth using carsons rule. Would I design the ...
0
votes
2answers
114 views

Quality Factor and Cut-off Frequency Defintion

Suppose we have $$ H(s) = \dfrac{ k \frac{\omega_o}{Q}s}{s^2 + \frac{\omega_o}{Q}s + \omega_n^2}$$ What is the definition of the quality factor? My understanding is that it is the gain at the cut-...
1
vote
2answers
67 views

Inverse Laplace transform of double pole

Given the simple transfer function of a double pole: $$ H(s)=\frac{1}{(1+as)^2}=\frac{1}{1+s2a + s^2 a^2} = \frac{1}{1+s k_1 + s^2 k_2} $$ Its inverse Laplace transform is (e.g. [1]): $$ h(t) = -\...
0
votes
0answers
46 views

'Information nature' of transfer function?

Doubt: before I thought I had understood the transfer function, now, I realize that I did not understand what transfer function is it on a structural level , that is how it 'makes a circuit' or is ...
0
votes
1answer
170 views

Transfer function of high pass filter via impulse response function

I'm having a hard time computing the transfer function of a high pass RC filter, by taking the Fourier transform of its impulse response function: $$ H(\omega)=\int_{-\infty}^{\infty} h(t)e^{-i\omega ...
0
votes
2answers
73 views

RC Filter measured response differs from calculated transfer function

I've created a first-order RC filter with R = 68 Ohm, C = 5.0 uF, and I am studying the transfer function of this filter. I have calculated the transfer function to be 1/(1+jwRC), based on the ...
1
vote
4answers
131 views

How to find the system response given the transfer function without using Laplace transforms?

The given transfer function is: $$\frac{6p+100}{p^2+12p+100}$$ and inputted into the system is a unit step response: $$r(t) = \left\{\begin{array} f0 & t < 0\\1 & t > 0 \end{array}\...
0
votes
4answers
275 views

Approximation of second order system, by step response

I am trying to aproximate a transfer function of a system. The system is a linear actuator, connected to a feedback potentiometer. The following figure is a step respons, with 24 V as input, and the ...
1
vote
2answers
79 views

Tip120 simulation shows explosion

I am trying to use TIP120 for my inverted switch where I wish to have my DC water pump(rated at 5v, 3W, 600mA) running when switch is open (in actual these will probes that will complete path when ...
0
votes
1answer
62 views

Find optimal gains transfer function

I have the following closed loop transfer function: $$G(s) = \frac{K(s^2 + 200^2)}{0.05s^3 + (1+K)s^2 + 200{K_v}s + 200K}$$ Where \$K\$ and \$K_v\$ are gains. My goal is to find the optimal gains ...
1
vote
2answers
66 views

Transfer function of Operational Amplifier

I am trying to solve the following operational amplifier circuit to get its transfer function. I have tried two different approaches, one is elementary approach by finding V- and V+ and equating ...
0
votes
2answers
59 views

Natural frequencies of a bandpass filter

I have the following frequency transform used to design a low-pass prototype out of a bandpass specification mask: $$\omega=\frac{\omega_0}{B}\left(\frac{\omega'}{\omega_0}-\frac{\omega_0}{\omega'}\...
2
votes
2answers
38 views

Systematic high frequency error in TF measurements

Full disclosure, I've asked a very similar question before which didn't have much success as it was too specific. However I want to try again by restricting the scope of the question. Scenario I'm ...
0
votes
2answers
69 views

What does “\$\cos(2t)u(t)\$” stand for in this context?

The question in the above diagram asks for "steady state current to \$\cos(2t)u(t)\$" of the network. I'm not sure what \$\cos(2t)u(t)\$ is, in this context. Is it the transfer function? Or something ...
1
vote
2answers
140 views

MATLAB Code to calculate intermodulation and Third Order Intercept (of an Amplifier)

My well annotated MATLAB code and plot is attempting to calculate the third order intercept of an amplifier. I have raw data of a non linear transfer curve, Voltage in (array) and the amplified ...
1
vote
2answers
248 views

Transfer function of phase change controlled with capacitance

We have an RLC series circuit with sinusoidal voltage source of frequency \$\omega\$. The normal transfer function of current to voltage is: $$ G(s) = \frac{I(s)}{V(s)} = \frac{1}{R+s L+ \frac{1}{s C}}...
0
votes
1answer
68 views

Determine by the order of transfer function what kind of filter

How can I determine by looking at the following tranfer function, that is this the transfer function of a band-pass filter: $$\frac{1}{as^3+bs^2+cs+1}$$
2
votes
2answers
855 views

Op-amps circuit with diodes

I am a beginner at electronics and I am trying to solve my first problems with diodes and opamps. I have to find and draw the output voltage uο related to the input voltage ui knowing that the voltage ...
0
votes
1answer
50 views

Second order transfer function

I’ve been struggling with this circuit for over an hour I’m trying to find the transfer function, can anyone help me with that? ![enter image description here] Here are my attempts on this: (https://i....
1
vote
1answer
66 views

How can I find the transfer function of a quadcopter's motor? [duplicate]

I want a model of a quadcopter and, thus, I need the transfer function of the motor. Any suggestions on how to do it will be very helpful for me. Thanks.
0
votes
2answers
455 views

Transfer function for a Passive Second order Low-pass Filter and to determine the components values

I am working on an assignment about Passive, second order low-pass filters. Cool little things if you get to know them. We are given the placements of the passive components (Inductor(L1), ...
0
votes
0answers
48 views

Roll-off of a third-order active filter [duplicate]

I've a third order active filter, without zeros. I know that when \$f=0\$ the gain response is \$1\$. So the cutoff-frequency is located at: $$\left|\text{H}\left(\omega_0\right)\right|=\frac{1}{\...