Complex-zero signal generator for rapid system testing

The expanding use of pole-zero techniques in designing feedback control systems has made paramount a simple method for determining characteristic pole-zero locations of existing systems and components. As a step in this direction, a method is presented for determining characteristic pole locations of a system. Use is made of a signal from a “zero generator.” This signal is fed into the system to cancel existing poles. A null method is used to determine when the pole is cancelled. The position of the zero given by the calibration of the zero generator then determines the location of the pole.