Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...

1.what is the role of proportional comtroller in pid
controller?2.How do u calibrate the control valve?

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 ?    10 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What are the key features of a Distributed Control System? describing the various layers (sensor through to business system interfaces) as well as the hardware, software and security aspects of the DCS.

2225


How many interlocks at turbine? Plz explain briefly

1957


How to Calibrate Level Switch in field

1338


why any measurement made interms of pressure is more accurate ? to be more precise most of the flow velocity is made interms of pressure and it is accurate. what is the reason behind pressure measurement being accurate ?

1911


What is zone,loop/fire alarm system?

2668


why we use impulse line of flow transmitter at 45 deg. angle both side of orifice plate.

2392


components of control circuit belongs to control valve

1659


What is cut off relay? And why use in PLC and DCS?

1374


How can you add value to this Industry if offered the job?

1596


How we calculate orifice plat size???

1530


what is actual drum level and compensated drum level?

2230


Why mixer nd grinder Is example of constant torque load not variable torque load ???

1958


draw shematic diagram of c/v positioner(smart type)?

2224


How can we test a bently nevda 3500/42M accelerometer monitor card by simulating it with test equipment?. what king od of signal (milli volts or volts or or resistance ) we should feed in the terminals of the card?

2460


what is gas metering system? gas chromatograph? and gas compressors?

2454