Question:
What is the primary trade-off in PID tuning?
Options:
A) Speed vs stability
B) Noise vs bias
C) Bias vs gain
D) Gain vs deadband
View Answer
Correct Answer: A) Speed vs stability
Detailed Explanation
The main trade-off in PID tuning is between:
Fast response (speed)
and
Stable behavior (minimal oscillation)
If tuning is too aggressive:
- High Kp
- Strong integral action
- Short rise time
But it may cause:
- Overshoot
- Oscillations
- Instability
If tuning is too conservative:
- Lower gain
- Slower response
- Very stable behavior
But sluggish performance.
Practical Insight
Good PID tuning aims to:
- Achieve fast disturbance rejection
- Minimize overshoot
- Maintain stability margin
Perfect balance depends on process dynamics (lag, dead time, gain).
Why Other Options Are Incorrect
B) Noise vs bias → Not the primary tuning trade-off.
C) Bias vs gain → Bias sets baseline; not a core trade-off.
D) Gain vs deadband → Deadband is optional and not fundamental to tuning philosophy.