Questions tagged [pid-controller]

A PID controller is a (closed) control loop feedback mechanism. It is used in industral control for proportional, integral and derivative feedback.

Filter by
Sorted by
Tagged with
0
votes
0answers
17 views

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 ...
1
vote
1answer
22 views

Advice on connecting heater directly to SP2 relay of PID controller?

I have an old Omega CN-9121 PID Controller and a 105Watts 115V Fibre heater mantle with an inbuilt K-type CHromel-Alumel temperature thermocouple also attached into it. I plan to use the PID ...
0
votes
2answers
91 views

main function is not defined [closed]

I am trying to build this code on MicroC using Pic16f877. It is a code using Kp and Ki values to control a motor. But when building, i keep getting the error main function is not defined. Below is the ...
1
vote
0answers
61 views

Closed-loop system with two cascaded P-controllers produces error increasing with time

The task: I control desired angle \$\theta_{d}\$ with two cascaded \$P\$-controllers, the outer is for desired angular velocity \$\omega_{d}\$ and the inner is for desired angular acceleration \$\dot{...
1
vote
1answer
34 views

Finding coefficients for a PID controller that minimize the integral of the squared error (ISE)

The problem The problem is to find the coefficients for the P, I and D terms of a PID controller used to regulate the object that minimize the the integral of the squared error (ISE): $$Q = \int_0^\...
0
votes
0answers
22 views

PI tuning from simulink scope?

I would like to use the method of Zigler-Nichols method for open loop. I got the step reponse from Simulink scope but How can I calculate the L and A from the scope?
0
votes
2answers
102 views

What do you do to help you grasp a concept or understand something you're seeing for the very first time?

Often in industry you come across a lot of different devices or even concepts you're seeing/hearing for the very first time. Things like encoders, resolvers, PID, pressure transmitters etc. I would ...
1
vote
0answers
34 views

Does having negative PID gains effects stability and realization of system?

Can we have a PID controller which has positive I gain and negative P gain? or will our system and controller will be not be realizable and will be unstable in this case due to a negative value of PID ...
0
votes
1answer
44 views

PID temperature controller

I am creating a Li-ion battery discharger. Only thing left is temperature control loop right now and I want to use PID for that purpose. I want to keep the temperature inside the device at max 95 ...
0
votes
1answer
83 views

Difference between stand alone pid and microcontroller based? Especially in terms of construction and applications? [closed]

My confusion is that what is the difference between a standalone pid controller such as the one shown in below link https://akytec.de/en/trm212.html And a microcontroller/microprocessor programming ...
1
vote
1answer
151 views

Analog PID vs digital PID? [closed]

What is the difference between hardware/standalone pid controller and that implemented in programming using microcontroller? I have also placed below links of two stand alone pid controllers https:/...
0
votes
0answers
37 views

Design of a controller

I am working on a project that requires me to design a controller knowing the following specifications: "The controller performance must be consistent under varying conditions. The rotor must respond ...
0
votes
1answer
45 views

Lag compensator vs pi controller?

Although Lag compensator and pi controller have apparently samd function of improving steady state response But how can we decide?which one to use?
0
votes
0answers
15 views

Lead compensator vs pd controller?

I have already studied that lead compensator is apparently similar to pd controller for both improve transient response But how can we decide?which one to use?
0
votes
1answer
49 views

Equivalent compensator of pid controller?

As we know that pi controller is equivalent to lag compensator and pd controller is equivalent to lead compensator, so what will be equivalent of lead-lag compensator?
0
votes
2answers
72 views

Controller vs compensator?

Both these terms: controller(forexample PID controller) and compensator(Lead compensator) are often encountered in control systems,but what is difference between these two? Brain douglas in this ...
0
votes
1answer
35 views

confusion regarding QNET VTOL(Vertical Take off and Landing)

I was reading a manual about QNET VTOL and i came across a block diagram(shown in attached snapshot) In the explaination of diagram, manual writes that The VTOL device is broken down into two ...
0
votes
1answer
32 views

4-20mA PLC analog output ground referencing for other devices

I'm currently using a PLC to control an induction heating coil. I'm using a chinese induction driver that allows 4-20mA PID input. This device runs off standard australian 230v AC 50hz. I've ...
0
votes
2answers
146 views

Difference between pid controller and on-off controller?

I want to know difference between pid controller and on-off controller especially in regards to the operation of both? The following link gives difference between pid controller and on-off controller ...
1
vote
2answers
44 views

Confusion understanding transient behaviour?

I am trying to simulate PID controllers in MATLAB Simulink, but I am bit confused by the term "transient behaviour" in how its extreme highlighted forms (aggressive and robust) will affect the system ...
7
votes
3answers
2k views

Confusion in PID loop?for 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 zero, e(...
2
votes
2answers
149 views

Why use PI controller for speed, instead of full PID?

I am building a two-wheels self-balancing robot and using PID controller to control its speed. The measured value is the encoder signals from the Hall sensors on the back of the DC geared motors. But ...
0
votes
1answer
35 views

Read Data from Temperature Controller using MATLAB, Need Help

I am trying to read data from a temperature controller called ATR-401 using MATLAB's tool box called Instrument Control Toolbox but every time i try to read data from it i get an error "A timeout ...
4
votes
3answers
1k views

How stable are PID loops really?

This is not a question about tuning PID loops for stability. I am assuming the output looks stable. The question is: Do PID loops ever achieve absolute stability, or is there inevitably a periodic ...
0
votes
2answers
61 views

Using PID relay to drive multiple contactors

I am a physicist by training but have been tasked with designing a heating controller box for a custom application that will be used in an industrial setting. I would like to make sure that I am ...
1
vote
2answers
93 views

How can I decide relay on-off periods depending on the PID output [closed]

In my PID project, I am using discrete time PID formula as follows. u(k)=u(k-1)+Kc * [(e(k) – e(k-1)) + (Ts*e(k))/Ti + Td/Ts * (e(k) – 2*e(k-1) + e(k-2)) As you know PID output increases over time ...
2
votes
1answer
198 views

Can my PID controller have negative p value and positive i value for a PID logic

I am building my first PID controller. My process variable and my actuator value are inversly related, meaning if actuator value increases process variable decreases, and vice versa. So I have tried ...
1
vote
1answer
55 views

µC control of a force testing machine

At work we have a machine that is used for testing and calibrating force sensors. It basically consists of a huge lever that is actuated by an electric motor with a gear reduction and a calibrated ...
3
votes
1answer
92 views

How to get from theory to a working Industry Control System?

EE Student here who recently finished the classical control theory class. I was wondering the process of how the industry or anyone goes from drawing block diagrams to actually implementing in ...
0
votes
0answers
28 views

Controller and compensator

What is the difference between controllers and compensators While searching for answer the most prominent answer I got was that compensator have magnitude=1 and is used to make sure the system ...
0
votes
1answer
252 views

Why fast inner current loop and slow outer loop of DC-DC converter

Let say we have a DC-DC converter operates with double loop control (inner and outer) , and with switching frequency of Fs= 20000 Hz. Please ,if you could answer the two following questions: 1- ...
1
vote
1answer
144 views

PID (Arduino) Project - Determining Ki, Kp, Kd

I am working on control system project. I bought a Zumo 32U4. It has built in encoders. The project is divided into three parts: a) Move in a straight line. b) Slows down as obstacle approaches. c) ...
0
votes
2answers
97 views

Why SSRs for heaters?

In the context of building PID controllers for very large heater systems (ovens, kilns, etc.) nearly all the designs I encounter use an SSR to switch the load, a choice I don't understand. The power ...
0
votes
1answer
57 views

How to model a Electronic Proportional Control Valve

I am using a VSO LowPro Proportional control Valve (https://www.parker.com/Literature/Precision%20Fluidics/Miniature%20Proportional%20Valves/VSO%20LowPro.pdf) to regulate pressure into a closed ...
0
votes
1answer
53 views

System Identification in a closed-loop feedback system [closed]

I have an unstable system that doesn't have a useable output when open-loop excitation is applied. Subsequently I've used a controller to control its output. I want to use the system identification ...
0
votes
1answer
125 views

Heating rods control using PWM

I'm not an electrical expert and lately, I ran into a problem using PWM for steady control of a heating rod. Let's assume there is a set value (Temp in C) for the heating rod. I'm currently using a ...
1
vote
3answers
63 views

Obtaining Plant Input data from System Identification (PID)

I'm trying to obtain a mathematical model from a physical plant using MATLAB. Using the system identification tool you need the plant input and output data. I'm struggling to match the theory to my ...
3
votes
1answer
137 views

Find transfer function and step function for this circuit

Can someone help me to find the transfer function of this circuit (i want to have the tension through the capacitor I think) and the step response in order to get the voltage in the function of the ...
1
vote
1answer
365 views

When to use analog PID

So I am building a rather simple constant current load to test power supplies. I am using an INA138 for high-side current measurement with only 5V power (and I have reasons for that, unfortunately) ...
3
votes
3answers
122 views

How to make sense of speed vs Torque curves in speed control mode

I am operating my motor in closed loop speed control mode using motor controller. Toque vs speed curves gives us a relation between them which is one-one correspondence. But in a closed loop speed ...
2
votes
0answers
43 views

Ripple in output voltage

I am working on an Active Clamp Forward converter. Schematic is given here: Specs: Output voltage-5V Input voltage 26..42V frequency=500KHz Output power=10W It is working fine in open loop, but in ...
3
votes
1answer
52 views

PID: how to deal with delay between controller and a process?

In designing a digital pll, I'm facing a problema with a communication delay between the loop filter output and the frequency synthesizer (via SPI). If I dont consider the communication delay the ...
0
votes
1answer
213 views

How to implement low pass filter in the differential part of PID in time domain

I programmed PID in MATLAB: ...
1
vote
0answers
37 views

Values got from programmed PID are different from ones simulated in Simulink

Please also read Update I created a PID simulation in Simulink: where the Step block is set with parameters: ...
0
votes
0answers
30 views

How to stabilize the magnetic levitation system? [duplicate]

I have asked similar question before also but want to try again - Not able to levitate magnet for magnetic levitation project I followed everything from this project but still, the magnet is not ...
0
votes
1answer
129 views

Not able to levitate magnet for magnetic levitation project

I am following a hackster project on magnetic levitation here - https://www.hackster.io/jsirgado/magnet-levitation-with-arduino-eeeee4 However, I have followed everything but still, it's not working. ...
0
votes
0answers
41 views

Design PI a controller for a “kind of” non-linear system

I have to design a controller for a plant ("Base"). My problem is related to the input term B*T0: in this case I have one output and two input. I think that I can split the "Base" model in two parts "...
7
votes
0answers
91 views

A peculiar issue in an atomic force microscope [closed]

I'm not sure where else to turn for this issue. Hopefully you all can offer some insight. Sorry the title is so vague, I don't know how to explain this concisely. I am a teaching assistant for an ...
1
vote
2answers
201 views

What is the difference between these two op-amp circuits?

I don't understand why when we design a proportional amplifier, the feedback has to be negative. When I run the simulation in simulink I get the same result for both circuits.
2
votes
2answers
122 views

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 ...

1 2 3 4 5 8