Answer Posted / www.islamqa.com
Actually we can make it simple:
# P:
it's a controller gain which modify the controller o/p
proportional to the error.
# I:
it's a controller gain which modify the controller o/p
proportional to the integral of the error.
# D:
it's a controller gain which modify the controller o/p
proportional to error rate of change.
We have 4 parameters in our control loop to focus on:
1 - the rise time: the period of time during which the pv
get 90% of the desired sp value
2 - max overshoot
3 - settling time: the period of time during which the pv
get the desired sp value and saturate.
4 - error/offset
we can get it clear from this pic:
http://controls.ame.nd.edu/ame437/S2003/hw1/specifications.j
pg
Now we will take a look about the effect of each controller
gain on these parameters:
# P gain:
decrease rise time
increase max.overshoot
increase settling time
decrease error (but not eliminate)
# I gain:
decrease rise time
increase max.overshoot
increase settling time
eliminate error.
# D gain:
no effect on rise time
decrease max.overshoot
decrease settling time
decrease error.
the previous is guidelines to be in background while
dealing with PID,but they are not sharp limits.
Regards,
Ahmed Sabry
Control and Instrumentation Engineer
GPC - General Petroleum Company
ahmedsabry.online@gmail.com
CELL.: 00 2 0121367310
| Is This Answer Correct ? | 7 Yes | 0 No |
Post New Answer View All Answers
field bus transmitter calibration procedure tell me
For crude application in floating roof tank, how to calibrate a DP Transmitter? How is the floating roof weight considered?
what is the different between deflection type measurement and null type measurement in RTD?
how to change measuring units from mmwc to cubm/h in rosemount air flow transmitter with hart communicator fluke 744
What is the use of control cable?
How it the difference between force balance system and dispalacement balance system?
sir,would you please send me the Hindustan petroleum corporation limited papers(HPCL).my e-mail ID is ujjwal_sharma1983@yahoo.com
how many types of viberation transmitter and how to calibrate and where use of vibration transmitter
hi sir yhis is zahid ali i am preparing for the jspl at oct.4.please send me the recently updated sample paper.
Tell about your IFFCO plant visit.
Explain types of valves?
we are having yokogawa centum cs3000 dcs in our power plant. i need some of the operator guides NOT to appear in HIS0163 AND HIS 0162 but it shoul appear in HIS0164 HOW TO DO IT?
How to convert milliampares into flow??
what are procedure of sox-nox calibration
TECHNICAL/ARTITUDE