VENABLE TECHNICAL REFERENCE LIBRARY ABSTRACT - 3

Optimum Feedback Amplifier Design For Control Systems

Many designers think of control system feedback loop compensation only in terms of stable or unstable. In reality, there is an optimum error amplifier transfer function for any given loop crossover frequency and phase margin. The optimum design is shown to be the one with the highest gain below crossover and the lowest gain above crossover. There is a unique pole-zero placement to achieve optimum performance. This pole-zero placement and resultant circuit component values can be determined without trail-and-error. In addition, there is an optimum open loop crossover frequency (loop bandwidth) or any given phase margin.