operation of PID
operation of PID
(OP)
I WANT TO KNOW THE OPERATION OF THE PID IN THE ELECTRONIC GOVERNOR CONTROL CIRCIUT.HOW WILL THE SETTING OF THE P.I.D. AFFECT THE OPERATION OF THE ELECTRONIC GOVERNOR
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RE: operation of PID
What exactly do you want to know?
Gunnar Englund
www.gke.org
RE: operation of PID
This is your proportional band, and is equivalent to the droop, The less proportional band, the less droop. This is the difference between no-load speed and full load speed. Droop is measured in RPM, proportional band is measured in percent. I'll leave integral and derivative for someone else to answer.
yours
RE: operation of PID
I = integral time = offset correction timer. If everything is stable but set point and PV don't match, integral works on this.
D = derivative time. Anticipates future PV and overrides normal PI control if something is rapidly changing.
RE: operation of PID
edenuh; The short answer is the better the PID settings the "better" the governor will control. It also means that miss setting the PID will result in virtually no control or dangerous oscillations.
RE: operation of PID
Not enough, or too slow gives poor and sluggish correction. Too much or too fast can over correct, causing stability problems and even continuous cycling.
PID tuning is selecting "how much" or gain, and "how fast" integral (and derivative if actually used).
RE: operation of PID
between the accuracy, speed of reaponse,stability
etc. within the physically possible limits to approximate
-- as well as possible -- the impossible requirements.
Engineering is the science of compromise.
<nbucska@pc33peripherals.com> omit 33 Use subj: ENG-TIPS
Plesae read FAQ240-1032
RE: operation of PID
The way I look at it:
Proportional gain is for controlling the amplitude or scaling.
The integrator fixes the steady error which is often
an offset from the setpoint.
The derivative sets the damping. It fixes how fast the
overshoot or ringing gets damped or aligned with the target
[setpoint].
The traditional way to tune PID is to start with just the proportional with everything else set to zero. Then adjust the integrator to eliminate the offset, then adjust the
derivative to get the damping. However, these are all interrelated and may have to tweaked each other 'til you
get. If you search google, I'm pretty sure you'd find several methods of doing this.