Third Order Control System

This circuit is a third order control system that also functions as an error amplifier. The system has a pole at the origin for the purpose of tracking constant references in a loop. Two zeros at the same location are strategically placed below a desired crossover frequency. Two poles at the same location are strategically placed above a desired crossover frequency. Actually the crossover frequency is the geometric mean between the frequency of zeros and poles. The purpose is to perform error operation and also provide phase boost and gain of a greater closed loop circuit.