Questions tagged [closed-loop]
The closed-loop tag has no usage guidance.
83 questions
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How to deal with controling force by positioning oscillating magnet?
I am trying to code up a closed loop control system on force generated by the paring of strong rare earth magnets. I do not have much experience with PID logic but i have a weak grasp of the basics (...
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Closed-loop position control with a stepper motor
Disclaimer: I understand this might not be the optimal setup for this application, but this is what I currently have available.
My controller is connected to:
a stepper motor with a lead screw for ...
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Can an open loop system replace a close loop system
I'm thinking about a mathematical possibility how an open loop system can replace a close loop system so here is my explanation
Let's say I have a plant with transfer function as given in image (1)
...
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What micro-controllers are suitable for a closed-loop DC Motor? [closed]
I am working on a small experiment on a closed loop DC motor for speed control.
The DC motor is separately excited and fed through a DC chopper.
I would like to know what are the best micro-...
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Closed Loop Transfer Function - PD Control
For the following control system, I am trying to find the characteristics of the system.
I have firstly found the closed loop transfer functions \$T(s) =\frac{C(s)}{R(s)}\$ , to be:
\$G(s) =K_p(s+9)...
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Closed Loop system with a second order dominated response on the verge of instability
I have the forward path transfer function of C(s)G(s) = K/s(s+3)(s+7) and want to find K so that it is second order dominated on the verge of instability.
But i'm not sure how to find it when it is ...
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Dominant Pole Approximation for loop gain
I have the following loop transfer function for a unity feedback system:
I understand that the \$(s+2)\$ term becomes \$2\$, but what happens to the \$s\$ ?
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Closed loop vs. open loop system analysis and design
I have found questions similar to mine in the forum but none were quite answered to my full satisfaction. I have two questions:
1) Why is controller design is traditionally done with the open-loop ...
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PID controller - should terms be completely independant?
I was under the impression that the P, I and D terms of a PID controller should be calculated independently of each other. That is, they would all use the same error information, but none of the three ...
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Closed loop equation initial value
I am doing math for a closed loop equation. I know the transfer function for a closed loop system is:
(Image copied from "Loop Gain and its Effect on Analog Control Systems" by Gabino ...
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Improve the performance of Buck Converter Loop Stability
The following are the specifications of my Buck Converter.
Input Voltage Range : 6V to 16V
Output Voltage : 5V
Switching Freq : 2.1MHz
Output Inductor : 22uH
Minimum Load Current : 200mA
Typical ...
user220456
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Drive signal (duty cycle) calculation for PI compensator
I am trying to simulate an inverter with 4 ideal switching devices in LTSpice. I have the compensator working, however I don't the correct equation in terms of calculating the duty cycle.
What I ...
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Dependent vs. independent current paths
Taking the following circuit:
The path on the left will be on and the same, whereas the path on the right is dependent on what is connected to the base of the transistor (not shown in the above ...
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Confusion regarding root locus. Open loop or close loop?
Which transfer function ,open loop or close loop do we use/need as a pre req to perform root locus analysis?
I have also attached a snapshot of the relevant webpage of university of Michigan.
I have ...
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Circuit stable in the Bode diagram, unstable in step-response
I am designing a simple current control circuit and trying to simulate it in LT Spice. The circuit is not optimized for some real-world application, it's more a learning method for me to get grip on ...
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How does opamp open-loop gain affect closed-loop gain in a circuit?
The gain of an opamp circuit is basically $$A_v=-\frac{R_f}{R_i}$$
But how come the gain of the opamp itself does not appear in the equation? How is the opamp amplifying anything in the circuit? What ...
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Calculate closed loop gain with Oscilloscope measurements
Using these reading from Agilent MSO-X2012a oscilloscope:
from this circuit:
How do you calculate the close loop gain using these measurements. I already calculated by hand and got Av = 11V.
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Phase margin is 90° but transient step response shows overshoot
The Bode plot of the loop is as shown here:
The transient step response looks like this:
The block diagram looks something like this -
basically a single stage op-amp (OPAMP in figure) with high ...
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633
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To prove that Close Loop transfer function is sensitive to perturbation in H(s) but not to perturbations in G(s)
The feedback control system with high gain K is shown in figure
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how to display an output variable from a speed sensor to a 7 segment display in C. DSPIC33E
I have just started an electrical engineering degree and been set an assignment to create a closed loop motor speed control system in C programming language.
The PIC is a DSPIC33E (BLO032) and the ...
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Proportional Control Balance Beam
Bit of an unorthodox question I'm sure, but I'm making a balance beam (two rotors on either end of a see saw) with proportional control, and I can't seem to get it to balance at 0.
The proportional ...
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What is the difference between 'x' and 'plus' symbol in the block diagram
Generally speaking, what is the difference between the 'x' and the 'plus' symbol in a closed loop block diagram?
For example, in
(https://ieeexplore.ieee.org/document/6983570)
, what's the ...
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SG3525 Closed Loop Inverter Waveform Problem
I'm using a sg3525 ic on a full bridge dc-dc converter in closed loop. The system is working fine, I don't have a problem with it. Output is just like what I want.
The problem is inverter part's ...
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Sample time of PI controller
I have designed a closed loop current control (PI controller) of a DC-DC converter in continuous time domain and it is working fine. The next task is discreetization of the controller and implement it ...
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Find gain of this common-gate
I have a large circuit involving feedback as follows
I am trying to find the closed-loop gain of this. Before I can do that, I need to find the open-loop gain. Thus, removing the feedback loop, M2 ...
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Where does the negative sign come from in this transfer function?
I have a transfer function that was given to me. It's been a really long time since I've done block diagram math, so sorry if this is a newbie question.
Based on the block diagram below (I forgot to ...
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Implementing PID in PWM feedback to lower the settling time
I have created the following simple PWM feedback:
The step response is:
I have tried to add PID controller and I ran the following code to test it:
...
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Why doesn't current flow in the other loop?
I am just now learning about how transistors work, so please let me know if I have a misunderstanding.
I ran a simulation of the circuit drawn below, and the results were that current flowed only in ...
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Closed current loop control without H-Bridge, PWM
I am trying to find a way how to control the Voice Coil Motor (VCM) or PMSM motor with a closed current loop without the use of an H-Bridge & PWM.
Does anyone know how to make an analog closed ...
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Cannot predict closed-loop gain of this amplifier
This is the circuit I am currently analyzing: (link to LTSpice file)
I am trying to predict each stage closed loop gain and overall gain (with all loops closed).
First thing I did is calculate DC ...
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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 ...
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Closed Loop control of a propeller
Hello I'm trying to control the velocity of the propeller with the pitch angle. I have a diagram from the factor cp over J and phi (see image: Draw.io diagram), but not a analytical formula.
J = v*60/...
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Understanding of Dominant Pole Compensation
According to Miller Effect, within amplifying devices such as transistors that have inverting voltage gain higher that one, there should be increased input capacitance with increased voltage gain of ...
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