Questions tagged [step-response]
For questions about the step response of an electrical system, which is the response of the system in the time domain to a unit step function input. Important characteristics of the step response include rise/fall time, overshoot, ringing, and settling time. Consider using in conjunction with related tags such as "rise-time", "control-theory", etc., if applicable.
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Damping gets better, but overshoot increases. How can I explain it?
I have three transfer functions as below
The pole-zero plot and the step response of the transfer functions are given as
It makes sense to me that G3 has a better damping than G2 and G2 has a better ...
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How does this work? Finding final voltage of capacitor in a RC circuit step response problem
There is a circuit with a switch which was in position 1 for a long time and is now in position 2. I attached a picture of the given circuit below.
Once in position 2 I need to find the final voltage ...
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Why can I ignore this part of the circuit during step response analysis?
I'm doing a RL step response analysis problem and I am confused on why we are able to only consider the left side of the circuit when the switch moves from position a to position b.
"The switch ...
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Help for RL step response
Here is the question I am trying to solve:
I didn't find Vo(t). What way should I go to find this value? ( Vo(t) is a voltage on 40k resistance after switch moves b.)
Here is my attempt: ( It looks ...
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Need help to find step response of RL circuits
Here is the question I am trying to solve:
I drew my solution with calculations on paper. Before the key is closed, I calculated İ0 and then after the key is closed, I calculated the last current (I∞)...
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Derivative of a waveform
I am self studying linear circuits and I came to a very basic problem.
The problem:
$$y(t) = e^{-t} u(t)$$
where \$u(t)\$ is the step function.
Calculate the derivative of \$y(t)^{\prime}\$.
My take ...
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Unexpected output from LC circuit
I am trying to get back into some electrical engineering basics, and had a quick question regarding an unexpected output I am seeing. I am trying to learn about RLC circuits again, and wanted to build ...
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What is the correct way of replacing the value of a step voltage source in Laplace?
I'll be presenting two ways to reach the same answer. I would like to hear which way is the correct way to get there. I am not interested in the result, it's the same in both cases, I'm interested in ...
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How to implement PWL or step function in CircuitLab?
I tried to implement a simple PWL (Piece Wise Linear) function in CircuitLab, and it does not seem to work. It differs slightly from LTspice, which I know how to use. The data points are in CSV (Comma ...
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How to prove property of transfer function for causal LTI system
For causal linear time-invariant systems the degree of denominator must be larger or equal than the degree of the denominator.
How can this be proven rigorously?
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How to derive phase margin and gain margin from experimental step response?
I have a fabricated closed-loop integrated amplifier circuit. Therefore, I can only conduct transient response experiments. How Do I derive the phase margin and gain margin from the experimental step ...
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Step response of critically damped PID controlled system
I thought that by definition: critically damped 2nd order system (ζ=1) does not have overshoot.
Is the above assumption wrong?
It might be on the verge of oscillation, but, it shouldn't oscillate.
...
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How to sketch the waveform of the voltage across capacitor and find equation that describes it? [closed]
Below DC voltage source, a switch, resistor and capacitor. At time \$t=0\$, \$C\$ has zero voltage across it and switch is closed.
How do I sketch waveform of voltage across capacitor v/s time and ...
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Differential equation of a LC circuit in series with a parallel RLC circuit
I have the following RLC circuit. I am having trouble finding an expression for the natural response of this circuit.
I found a similar question, but I was unable to simplify exactly like was done in ...
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How to calculate natural frequency and zeta of underdamped, 2nd order system if only given experimental data?
How do I estimate the values of \$K\$, \$\zeta\$ and natural frequency, given the plot of unit step response of the system in time domain?
I figured that at \$t = \infty\$, \$Y(t) = K\$ and I ...
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Graetz diode bridge with series LC circuit oscillation problem
I am trying to understand a problem I have encountered. I simulated the voltages on a Graetz diode bridge with a step voltage input of 24 volts. The schematic and the voltage signals are given below. ...
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High pass filter: Overshooting before attenuation
Working with a 2nd order Sallen-Key high pass Butterworth filter with a cutoff frequency of \$f_c=0.5\$ Hz I am having difficulties making sense of a result that I got:
After applying at its input a ...
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Harmonic response of PID only works if multiplied by a large number?
I am trying to control just one motor using a H-bridge as shown in the picture (one motor only). I am attempting to use PD control, but for some reason I only obtain a sin wave when I multiply sin(x) ...
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Using lag-compensator to get good system response - RHP zero
I am designing a velocity controller for a balancing robot. The most important thing for the robot is to maintain balance, so I would prefer a slower response velocity response in turn for a steady ...
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Velocity control system is stable even though CLTF has a pole at s=0?
I was reading about steady error calculation for system with H(s) having Nth order Zero at s=0.
In book it is written that steady error calculation is meaningless when closed loop transfer function(...
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Finding the output time response of a transfer function with a step response
The question is finding the output time response of the transfer function below. I solved that it is an underdamped response. The step response is 1/s.
$$T(s)=\frac{20}{s^{2}+6s+144}$$
According to ...
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Can I remove my step response overshoot?
I am working on a balance controller for a robot. I found the open loop transfer function between the motor voltage and robot pitch angle:
...
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RC filter impulse response is exponential decaying but inverse Fourier is Sinc function
As we all know that the inverse Fourier transform of a frequency domain unit pulse/rectangular function (which looks like low pass filter) is Sinc function. So, I was under the impression that any low ...
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How can I find the current in the resistor,when I found inductor current in this question?
Previous part of the question, I found the inductor current (from natural and step force). But here, I think it asks 10 ohm resistor's current. How can I find it ?
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What happens when the direction of initial current through an inductor is opposite of the direction of applied current?
I am having trouble understanding the behavior of current through an inductor when the direction of applied current is the opposite of what is initially flowing through it. An example is that when an ...
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After being open for long time, the switch in circuit closes at \$t=0\$. Determine \$I_1(t)\$ for \$t>0\$, Steady State Current and Initial Current
I am seeking guidance on this Assignment [Homework] Problem regarding RL circuits because me and my study group are getting two different answers and we don't know why.
Question : After being open ...
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How to handle delta function after finding the impulse response?
I am pretending that laplace does not exist because I am being tested on these concepts separately.
Essentially, I have solved for the step response of a first order circuit and found it to be:
$$v_{c}...
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Step response of voltage inverter and RC filter homework question
This is my solution so far:
Vth would simply be the output of the inverting op amp which is Vth = -(Rf/Ri)Vi
Rth would simply be R2 || R3.
simulate this circuit – Schematic created using ...
user263783
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Differentiator step response
I have one ideal and one practical differentitiator circuit in Multisim to which I am applying a positive, say 10 V step response. The output I get has a much lower settling time at final value of 0 ...
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How to analyze a capacitor connected to a DC voltage directly (no resistor)?
This may be a very basic question but my misunderstanding is due to the difference between how physics explains the charging of capacitors and how we analyze circuits in circuit analysis.
According to ...
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Undervoltage Testing of a LDO or Switching DC-DC Converter
I am using a Regulator section in - UJA1076 this IC
Input Voltage = 16V
Output Voltage = 5V
Load Current = 0.1A
My question is, I want to test the undervoltage condition 90% and 70% as mentioned in ...
user220456
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How to estimate settling time of an overdamped system?
I've been trying to figure out how to estimate the settling time of a second order system in response to a step input of magnitude 5.
The systems transfer function is $$G(s) = \frac{1}{(s+2)(s+4)}$$ ...
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Is there an English word for the output response of a non-minimum phase system?
I've noticed in some French language control courses they have a word for the initial part of the response of a non-minimum phase system. They say it has "un départ malin". I looked up ...
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Confusion Between Dual Capacitor/Inductor Circuits
I'm trying to physically understand the responses of this pair of (dual) circuits: a step current source driving a capacitor and a step voltage source driving an inductor.
simulate this circuit &...
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(Convolution Integral): What does it mean to have an impulse response before t=0?
Context: I am currently learning about convolution integrals as they apply to circuits (LTI specifically, if I understand it correctly.
(For the following, continue under the assumption that \$\theta(...
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Underdamped RLC with CCCS, calculating capacitor voltage
Referring to "Electrical Circuits" Nilsson/Riedel 10th Edition.
I have a classic underdamped RLC circuit with a CCCS (Current Controlled Current Source) with a current multiplication factor ...
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Finding the voltage and current at t = 0 using Step Response
The question that I'm trying to solve is as follows:
In the circuit shown below, the switch has been closed for a long time. a) What is v(0) or the voltage across the capacitor immediately after the ...
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Find 2nd order transfer function from step response
I have to find the tranfer function from the following step response. I would've known how to do this if the system had a steady state. Unfortunately, I don't even know how to begin this task.
I know,...
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RC circuit with two voltage sources and finding I(t)
I would like some guidance on this problem that I have:
This is the circuit:
And the question is:
Note: typo in the question, closes should be closed.
So my take on the question is:
There is ...
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Feedback response in linear system
I have a linear system with transfer function \$G(s)\$ that is connected in negative feedback with a real value gain \$K\$.
Therefore the open loop transfer function is \$K \cdot G(s)\$
and the ...
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RC circuit with current and voltage source
I am once again stuck on a task. The circuit initially looks like this:
And the question is:
So my attempt:
The first thing that came up in my mind was that the switch had been closed for a long ...
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Using KVL for a mesh with a switch and inductor in parallel with capactior
I'm currently studying for second order circuits, and I'm stuck understanding this example in my book pictured at the bottom.
I got the same KCL equation, but I don't understand why the KVL equation ...
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RC circuit with open switch and calculating energy
Yet again a similar task, however this time I'm supposed to find the energy stored in the capacitor.
This is the circuit:
And the questions are:
And this is how far I have come in the problem:
...
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RC step-response and how to go about voltage across capacitor
I have this task with this circuit:
and the question is:
First I looked what would happen when t = 0:
To begin with, Vc(0) = 0 V, the reason for that is that t = 0 and before that the switch has ...
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How to determine the step response given a transfer function?
I would like to know how to draw the step response given a transfer function.
For example, given \$G(s)=\frac{(1-\frac{s}{3})}{{(\frac{s}{0.1}+1)(\frac{s}{100}+1)^2}}\cdot 10\$ a transfer function, ...
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How to find second order transfer function from a graph?
I have been given this step response graph and asked to determine the second order transfer function of the system. I completed the question, using a lot of help from this post and got the answers ...
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How to represent the lag/settling time of a DC motor?
I have a 12V brushed DC motor and I need to calculate its lag/settling time or latency in other words. I did some experiments in which I gave motor DC supply of 5 volts recorded motor's steady-state ...
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Convolution integral with step function
for the following convolution integral
$$ \int_{-\infty }^{\infty}\sigma (\tau)\tau A\sigma(t-\tau)\sin(t-\tau)d\tau \text,$$ where \$\sigma(t)\$ denotes the step function
We'll only get results ...
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How to find I(t)?
so I'm trying to find the current I(t) passing through the node above the switch.
I have already found the DC response of the RC circuit which is
in the form of:
so, after the switch closes a short ...
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Nyquist plot disagreeing with the unity step response of the closed loop
Let us assume that the open loop transfer function of my system is:
\$L(s)=\frac{10(s+1)(s+2)}{(s-3)(s-4)}\$
Also, the system has unity feedback, meaning that the closed loop transfer function is
\$...
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