Which of the following should be done to make an unstable system stabl...
Explanation: The gain of the system should be increased to make an unstable system stable and for positive feedback of the system the gain is more and for the negative feedback the gain is reduced for which the stable system can become unstable.
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Which of the following should be done to make an unstable system stabl...
Introduction:
In control systems, stability is a critical characteristic that ensures the system's output remains bounded and does not grow indefinitely over time. An unstable system can lead to unpredictable behavior, oscillations, and even system failure. To stabilize an unstable system, certain measures need to be taken.
Explanation:
There are several methods to stabilize an unstable system, but in this case, the correct answer is option 'B' - increasing the gain of the system. Let's understand why this is the correct approach:
1. Understanding System Stability:
To understand why increasing the gain can stabilize an unstable system, we need to understand the concept of system stability. The stability of a control system is determined by the locations of poles in the system's transfer function.
2. Poles and Stability:
Poles are the values of s at which the denominator of the transfer function becomes zero. In a stable system, all the poles should have negative real parts or lie within the left half of the complex plane.
3. Unstable System:
An unstable system has at least one pole with a positive real part or lies in the right half of the complex plane. This positive real part causes the system's output to grow indefinitely over time.
4. Increasing Gain:
By increasing the gain of the system, we can shift the poles towards the left half of the complex plane, making them have negative real parts. This shift in pole locations transforms an unstable system into a stable one.
5. Root Locus:
Increasing the gain can be achieved by adjusting the proportional gain in a control system. This adjustment can be done using a root locus plot, which shows the movement of poles in the complex plane as the gain varies.
6. Effect on Stability:
As the gain is increased, the poles move towards the left half of the complex plane. If the gain is increased sufficiently, the poles can be shifted completely to the left half, resulting in a stable system.
Conclusion:
In summary, to stabilize an unstable system, the gain of the system should be increased. This adjustment shifts the poles from the unstable region to the stable region of the complex plane. It is important to note that increasing the gain should be done carefully to avoid overshoot, oscillations, or other undesirable effects. System stability is a fundamental concept in control systems design and plays a crucial role in ensuring the desired performance and behavior of the system.
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