Control Systems Interview Questions Answers

**What is Resonant peak?**

Answer: Resonant peak is defined as the maximum value of the closed loop transfer function.A large resonant peak corresponds to large overshoot in the transient respose

**What is Resonant Frequency?**

Answer: The frequency at which resonant peak occurs is called the resonant frequency. Resonance frequency explains about the speed of the transient response.

**What is Cut-off rate?**

Answer: The slope of the log-magnitude curve near the cut-off frequency is called the cut-off rate. The cut-off rate indicates the ability of the system to distinguish between the signal and the noise

**What is Phase cross over frequency?**

Answer: The frequency at which the phase of the open loop transfer function is 180o is called the phase cross over frequency.

**What is Gain Margin?**

Answer: The Gain Margin is defined as the reciprocal of the magnitude of open loop transfer function at phase cross over frequency. The gain margin indicates the amount by which the gain of the system can be increased without affecting the stability of the system

**Phase Margin?**

Answer: The phase margin is the amount of additional phase lag at the gain cross over frequency required to bring the system to the verge of instability.