In: Electrical Engineering
When designing a lead-compensator for a given transfer function and having the freedom to choose any value for the damping factor, can you choose the damping factor to be 1 and have the desired pole lie on the real axis?
When a lead compensator is added to an uncompensated system then the value of damping ratio increases which in terms reduces the rise time and overshoot of the system. It also provides a faster transisent reponse and bandwidth of the system also increases. Overall addition of a lead compensator will make the uncompensated system more stable.
While designing the lead compensator if we choose to have damping factor equals to 1 then the system become a critically damped system that implies there will be no oscillation , no rise time and no overshoot in the output response along with that the system response will attain a steady state value with a shorter time period.
When damping ratio becomes equal to 1 the poles of the closed loop system will lie on the real axis.
So damping factor of 1 is an ideal case for lead compensator design and it is always advisable to have a damping ratio nearer to 1.