Questions tagged [closed-loop]
The closed-loop tag has no usage guidance.
73
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How to make a circuit of 6 lights connected to a single battery, with each light having its own switch [closed]
I have a school assignment on how to make a circuit with 6 lights connected to a single battery, with each light having its own switch. I'm wondering how to do this, and I'm hoping for guidance.
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Measuring Motor Speed in an analog circuit - (no digital components)
I have been searching for several resources on closed-loop analog motor control. Most of them used a tachometer for speed measurement, which makes a lot of sense because the tachometer is analog and ...
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Why do we talk about system stability as a whole when Barkhausen criteria is valid only for one specific frequency?
The relationship AB=1 will be applicable only at a specific frequency. For instance, following is the bode plot for a circuit I have and as can be seen, the barkhausen criterion is met only at 6.3MEG ...
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How to determine the phase margin when the Bode plot never crosses 0 dB?
I have a graph that looks like this. I am tasked to measure the phase margin, but the graph doesn't exceed 0 dB.
The circuit is this. The input DC level is 0.6 V, which is the problem. When I change ...
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Closed loop system of servo motor for master and slave flex
I am really new in Arduino. So what I have is two flex sensor, a master flex for the left hand and a slave flex for the right hand. What it will do is that when the master flex is bent, the servo ...
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What would be the equivalent circuit of the following block diagram?
They gave me the following diagram, in the references they gave me I was able to obtain the PID block circuit, I only need the circuit of the \$\frac{1}{s-2}\$ function, It sounds like an RC circuit ...
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238
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CL57T stepper driver not working in closed loop mode
I've bought https://www.ebay.de/itm/393715526356 CL57T with NEMA 23 and it works well in open-loop mode but in closed-loop it goes into 7-blink error mode.
https://photos.app.goo.gl/BnkV1mTWC3q8ZEC99
...
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Controller for boost converter
I'm trying to design a controller for a boost converter by the "shaping loop gain" method as in the Fundamentals of Power Electronics textbook by Ericson and Maksimovic.
I see that there is ...
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Closed loop stepper with unshielded wires
I've bought a closed-loop stepper from a somewhat reputable manufacturer but was surprised to see 2 things:
Power cable is MUCH shorter than the signal cable (they both go to the same place - driver)
...
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Bode phase plot phase margin
From what I have studied so far, gain margin is defined as how much additional gain the system can be given before it becomes unstable, and this can be measured from the bode magnitude plot ...
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Multi-Pole System - Why is there no bandwidth extension if loop gain is reduced?
[Design of Analog CMOS Integrated Circuits by Behzad Razavi]
The author explains that if the feedback (beta) is made weaker, the plot shifts down and hence, we hit the GX earlier now, thereby ...
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Is it possible to sustain max speed in a closed loop DC motor PID algorithm under increasing load?
I understand that in a closed loop DC motor control system, the voltage (or PWM) can be increased or decreased to keep the speed constant, by using a RPM sensor and a PID algorithm, for instance. ...
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364
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Phase shift oscillator: what is reducing loop gain and how does changing feedback resistor affect things?
I have simulated the following circuit in LTSpice:
One can see that a stable sine wave with a peak of about 6.3 V is obtained, which has a frequency of 1 kHz (I calculated the RC network values to ...
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Need help to understand op-amp input resistor and capacitor network
I'm trying to understand the circuit design from this application note.
Here is the figure:
The author said:
Resistor RIN provides a dc return path for the VS/2 reference voltage and sets the ...
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362
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Closed loop control of a stepper motor (i.e. servo system)
Crucial to the performance of a CNC is its ability to precisely, accurately and quickly move
to the directed position. Stepper motors are perhaps the most popular (and therefore
cheapest) motors ...
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On the stability of differentiator based on OP amp with an example from TI manual
I am building a proportional-Differentiator circuit based non-inverting OP-amp. But I am confused with the stability condition of OP-amp.
The system will be unstable if the loop gain |T(s)|=|a(s)B(s)|...
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The output of PI controller using opamp is not working [closed]
I am designing a closed loop system for dc-dc converter for that I am using error amplifier and pi controller. For error amplifier and PI controller I am using OP177A opamp. The error amplifier ...
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How can we confirm whether the op-amp has -ve feedback? [duplicate]
Many text books show an op-amp will have negative feedback when o/p is connected back to -ve input through some discretes and under such condition V+=V- is satisfied for op-amp input terminals.
In the ...
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Define input impedance of a buck converter for ideal converter (efficiency 100%) & practical converter
What I know was -The input impedance by the closed-loop buck converter in CCM mode, Zi and, in turn, that presented impedance is dependent on Zo and the duty cycle used by the buck converter
below is ...
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Can any one explain what type of compensation is this
I will be using the UC3844 controller IC in combination with TL431 to achieve peak current mode control in a 150W forward converter. After some research, I found this schematic on the internet:
There ...
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H-bridge class D amplfier [closed]
i am trying to make a closed-loop class D amplifier for a dissertation. I have the basics:
audio signal-->pwm modulator(LTC6992)-->gate drivers->H-bridge-->LC filter--> speaker
but i ...
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2
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Ideal closed-loop gain derivation for negative feedback
Considering a negative feedback system, the closed-loop transfer function Af is given by:
where A is the open-loop transfer function and AB is the loop gain.
Every text I read says that if the ...
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Peltier quick heating and cooling
I am using a Peltier module to quickly heat and cool down the object placed on it to a particular temperature. My target is to heat the object to 90° and then cool it down to 54° and then heat it ...
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Setpoint weighting algorithm for the PI controller
Some time ago I found an interesting modification of the standard PI controller algorithm.
The modification is called the setpoing weighting in the literature and regards the proportional component of ...
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4 wires encoder to 6 wires Hibrid Servo drive for closed loop stepper motor
I have the HBS860H driver and LPD3806.I wanna know if I can connect this 4 wire encoder, to this 6 wire driver.
HBS860H:
https://hardware-cnc.nl/images/PDF/ACT/HBS86H_English_Manuel.pdf
LPD3806: (i ...
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what is the open and closed loop function of this system?
i found this in the text book.
i solved by:
1- found the closed loop function of just the part of B(p) and its "feedback", let's call it B'(p).
2- after that i did H(p) = A(p) / ( 1 + A(p) * ...
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Interesting driving circuit of a voice coil actuator
I have an interesting circuit to drive the voice coil stage of an old acoustic microscope. I am struggling to understand what the different functions of the opamps in this circuit are.
The circuit ...
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Determine if the system is stable [closed]
Determine if the system is stable?
How is this done? Is this at one frequency? Is the Loop gain is A x B x C = 0.5
Should phase angles be added together = 173 degrees?
Should I be considering the open ...
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Confusion regarding finding closed loop transfer function and damping constant from open-loop transfer function
I have second order transfer function $$ G(s) = \frac{1.247}{s^2+9.76s+23.8}$$ G(s) is in the forward path of a unity feedback system.
How do I find the closed loop transfer function and damping ...
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Understanding Total Response
QUICK INFO:
I am currently studying about closed and open-loops systems.
BACKGROUND STORY:
Imagine a big antenna is placed on a hill and there is a lot of wind. You want to turn the potentiometer so ...
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unstable systems with positive phase/gain margin
Open loop Phase/Gain margins provide information on how much margin the closed loop system have until it becomes unstable. In other words, how much you can increase the effective loop gain and or ...
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buck small signal modelling
I have a synchronous buck converter and my inductor current looks like this:-
To add voltage-mode closed loop control, I need to do the small signal modelling of the converter. I am a bit confused if ...
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Bode plot in Pspice
I want to get the bode plot of the controller part of my Buck converter. For this I looked online and saw a technique that mentioned to add an AC injection source from the voltage output to the top ...
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Closed loop system stability with Bode
Stability of the closed loop system (with -1 feedback) can be assessed via Bode plot gain/phase margin analysis of its open loop system.
How can one deduce stability of the closed loop system directly ...
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Why is the slope of the op amp graph 20 log (AB) in this application note
I am going through the following guide for op amps :
http://web.mit.edu/6.101/www/reference/op_amps_everyone.pdf
On page 87 (screenshot attached) there is a bode plot which has got me slightly ...
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Open and Closed Loop Amplifier Circuit
For example, say that a system requires an input voltage of 5V, however, you only have a source that can provide 1V. The use of a voltage amplifier is obviously the solution to the problem. However, ...
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What is the significance of phase margin in an open loop amplifier?
I know the importance of phase margin to ensure stability in closed loop systems, but what about in open loop systems?
I am designing a regulated common based LNA IC that operates in open loop.
Can we ...
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What is the controlled variable in this particular case?
I have a question, maybe you can help me because I am not sure of the correct definition.
As an example I have a plant with a measured output y in a closed loop system. But as the feedback variable I ...
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closed loop pole of negative feedback
given w be the pole of open loop what in the pole of the closed lop shown bellow?
i have found axpression for GAIN but for the pole i am not sure.
Thanks.
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Can a strong electric field generate an electric current within a closed loop of wire?
I would like to know if an electric current can be generated in a closed loop of wire by using a strong electric field to circulate the free electrons within the closed loop of wire.
Say that you have ...
user263061
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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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