Questions tagged [control]
Control refers to systems that control other systems, whether that be industrial machinery, lighting or devices used in a home
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Switching DC with MOSFET: p-Channel or n-Channel; Low Side Load or High Side Load?
I think, it is time I understand working principle of MOSFET transistors...
Suppose that;
I want to switch voltage on a resistive load by a MOSFET transistor.
Any control signal between -500V and +...
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Poles and Zeros in English
Can someone explain, or provide a good reference to an explanation of Poles and Zeros for say, a power supply compensator, or any control system for that matter. I'm not really looking for a ...
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What is the advantage of a Z transform derived PID implemenation?
I've seen many PID articles, such as this, use a Z transform of the generic PID equation to derive some crazy difference equation which can then be implemented in software (or in this case an FPGA). ...
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In earlier tape recorders, how was tape spool angular velocity adjusted?
Tape recorders that use spools of magnetic tape transfer the tape from one spool to another as the tape plays/records. The spool with less tape must be rotated faster than the other. Here is such a ...
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How do I come up with a list of requirements for a microcontroller for my project? How can I then find microcontrollers that fit?
I have been working on an eBike control project on the Arduino MEGA2560. The program runs 3x PID control loops, one battery capacity control loop (interpolation based on lookup tables), a speedometer (...
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Control differences between ac induction motor and brushless dc motor?
I have a fairly solid background in industrial AC motor control (soft starters, VFDs, etc.) but something that I'm certainly NOT well versed in is brushless DC motors... the type found in every hard ...
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PID algorithm: how to account for fast input value changes after a long delay
I am trying to implement a basic PID algorithm on an Arduino Leonardo to mix hot and cold tap water using servo-controlled valves. The goal is to hold the temperature as close to a setpoint as ...
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Stability problem in unity-gain opAmp
As a part of a controlled power supply for hardware-in-loop testing for a student driven project, I had to develop a current buffer (voltage follower) which could source up to 1 A.
I had the (bad) ...
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What is the name of the protocol(s) used to let an automatic garage door opener know which button I've pushed on the wall control panel? [closed]
The wired wall control panel in my garage has only 2 wires connected to it.
Yet somehow it acts different when I push the big "door" button than when I push the "light" button or the "lock" button.
...
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Why isn't the Fourier transform of a single sine wave cycle a single bar?
I have tried different Fourier transform codes out there on single sine waves, and all of them produce a distributed spectrum with a resonance at the signal frequency when they should theoretically ...
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Controlling High Voltage device with Arduino
I want to control lava lamps using Arduino. I think it shouldn't be hard project, but I have no experience with hardware projects so I'm not sure witch design will feet best for me.
I consider using ...
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What is causing this long tail in the transient reponse?
I have a fifth order transfer function for which I designed a controller using pole-zero cancellation technique on a root locus. I am targeting \$<5%\$ overshoot and \$<2s\$ settling time. ...
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What are the effects of removing P, I, and D from a PID controller respectively?
A proportional, integral, and derivative (PID) controller can feature three terms.)
We sometimes see only two of the terms in use. For example, the derivative is disregarded for a PI controller. While ...
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Why do we use closed-loop feedback in buck converters?
My power electronics professor spent most of his life in the time domain and in application-specific theory (SMPS-only vocabulary).
For me, a buck converter is basically a square wave (generated by a ...
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Why do we use step response? [duplicate]
We tend to identify systems more often by using the step response. Why? Especially when the impulse response is directly related to the transfer function?
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Feeding a Full-Bridge from a Boost Converter?
I have been researching about designing a 3kW DC-DC Converter (Vin 12V from a battery, Vout 350VDC) and actually wired up a simple isolated Full-Bridge based DC-DC converter a few days back converting ...
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What is meaning of "classic" control in context of EE?
As electrical engineers, we often come across the terms "classic control" & "modern control"
What does classic mean here? Is it meaning "old" or of "past time&...
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How to tune a PID controller to a nonlinear process
I have a nonlinear thermal process (nonlinear radiation becomes more and more present as temperature goes up) that I would like to tune a PID controller to. I'd like to control the temperature as ...
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What is a "dry contact input"?
I'm a PC software guy, a newbie to electronics. Recently, I've got a project in which I need to source for a DAQ that can provide dry contact inputs to an interfacing digital output controller. The ...
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Is it possible to determine load on a stepper motor when stopped
Is there a way that the torque on a stepper motor can be determined without some kind of additional force sensor.
Additional electronics such as current shunts etc would be acceptable.
I would like ...
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Please explain in layman's terms how a PID accounts for inertia in temperature control
I'm building my own hobbyist microprocessor-controlled reflow oven. I'm using (mechanical) relays to turn the heaters (i.e. quartz tubes) on or off. I've noticed heating lags a couple of seconds ...
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Why do linear voltage regulators have minimum output voltage > 0 V
I am trying to pick linear voltage regulator for my project (lab. power supply).
I am stunned, that only very few regulators claim to have output adjustable to 0 V. It seems to be due to the fact, ...
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Longest range remote control
I would like to make a long range (5Km) quadcopter. As of right now, I'm just trying to find out the best way to control it. I know that there are some 5Km R/C transmitters but they are the size of ...
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What is meant by "plant" in control system?
What is meant by "plant" in control system? Does it also means systems like DC motor or it only includes large systems like chemical (fertilizer or cement) plant?
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AC fan speed control
I use this fan to cool my room, but sometimes it is too fast and I have to frequenctly turn it on and off to keep normal temperature. Maybe it is possible to reduce the speed by connecting a resistor ...
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How to use SCPI on HP33120A via RS232?
I have old Hewlet Packard 33120A function generator (it should be the same type as Agilent 33120A) and I would like to control it with MCU (ATMega). The generator has RS232 and use SCPI commands.
I ...
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Finding the Transfer Function of Spring Mass Damper System
I have been going through Ogata Modern Control Engineering book and working through several exercises to improve my understanding of basic control principles. I came across the following example which ...
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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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Weird servo mechanism
I want to use a servo taken by a radio-controlled car. However, I found out that wheels' rotation (front wheels) is not performed by a servo, but from a motor to move the wheels and a mechanism for ...
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How to design controllers "properly"?
It may sound like the "easy way" to ask it here, but this question (along with a couple others I've posted which were more specific) is the result of years of research on the topic - on and off as it'...
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Control theory: is there any actual application for D in ABCD matrix?
Recall that a LTI state space of a dynamical system is given as:
Is there any actual purpose for D in the output equation?
If D was not zero, it would mean that the output is "directly" dependent ...
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Why aren't Stepper motors used in closed-loop systems and PID control?
I know stepper motors are usually operated in open-loop systems. I'm curious to why they aren't usually part of closed-loop systems? Also why aren't PID control methods commonly used with stepper ...
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Confusion in PID loop for the case of zero error?
I am already studying PID control and some how to some extent I have understood it except one main confusion. When the difference between reference input \$r(t)\$ and current output value \$y(t)\$ is ...
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How do I find the second order transfer function from this step response diagram?
I have the following diagram of a system's step response:
I'm having trouble understanding how to calculate the system's transfer function, given this diagram. Specifically, I don't understand how ...
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Why is this MOSFET burning?
I have a system that powers a transformer via a line to line power supply of 115Vac(L-N) for a total of 200Vac(L-L)
In order to control the ON/OFF of the transformer, the NEUTRAL line is used to ...
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Using 240v mains on/off as input to microcontroller
I have a light switch that switches 240v (UK) mains. Instead of using that to directly control a light, I want to use it as an input to a controller board so I can also automate the lighting. (It's ...
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1-10V fluorescent lighting digital control
I have a number of fluorescent lights installed that use 1-10V dimming. Note that this is not the same as 0-10V dimming as used in older theatre equipment.
The control gear for the lights outputs 10V ...
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Implementing line propagation delay compensation for BiSS master in software
Following up on a question I asked some time ago: Simple Implementation of BiSS C interface for a position encoder. I have implemented a simple BiSS master (point to point) to communicate with an ...
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Adding foot control to tig welder
I've got a simple tig welder that uses a switch on the torch to start the welding current and a potentiometer on the front panel to set the amperage. Many welders make use of a foot pedal to start te ...
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Control one relay via multiple 12 V DC signals
I'm seeking help designing a circuit wherein we would have multiple 12 V DC signal inputs, with the goal of:
...
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Why are induction motors controlled with a constant V/f?
It seems that induction motors are always controlled using a constant ratio of voltage over frequency. Why is that? Take the classic torque-speed characteristic curve - varying the frequency shifts it ...
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Voltage regulator vs. voltage controller
I frequently meet the references to voltage-regulators and voltage-controllers. However, looking at the specs I find them to perform the same function. Is there a difference between the two, or ...
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Confusion in block diagram of open loop and close loop control system?
I am studying Modern Control Systems, 11th edition, by Dorf and Bishop.
On page 221 it first shows in fig4.7 open loop control system(the writer names it as open loop) and on page 222 close loop ...
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How to decrease solenoid speed?
My project is Speed Control of a solenoid. In this project, stroke is 30 mm and I want to plunger cross 30mm in a few seconds (like 5 seconds). For this purpose I want to control the current of the ...
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Dry, wet and free voltage contact?
I would like to ask about three kinds of electrical contacts: dry, wet and free voltage. ...
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Real device with derivative transfer function
Is there a device that has \$s\$ as its transfer function, that is, a physical system implementing a derivative?
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over and critically damped systems settling time
I know that for second order systems the settling time(St) equation is:
So my question is, should this same formula be used when the system is over or critically damped? Is it right to use it in that ...
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Buck Converter Control Scheme- Why isn't just a comparator not enough?
I am supposed to come up with some control schemes for the converter before understanding the standard PWM control scheme.
Isn't it just enough if the output of the converter is compared with a ...
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Using the iPhone to control a remote controlled car via Arduino
So i started this project a while back where i made a remote controlled car that i could control with the directional buttons on my keyboard via an Arduino -> now the next step i want to do is to get ...
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Analogue automatic gain control
I have to amplify a microphone signal to be in the range -2.5 to +2.5V. It is currently providing a signal that has a peak amplitudes of around 2V. This, however, is highly dependent on the situation (...
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