Assume that the system has only one input, r (s); Single output C(s), forward channel transfer function G(s) and negative feedback H(s). What is the closed-loop transfer function of this closed-loop system? Gb(s)=G(s)/( 1+G(s) H(s))。
The open-loop transfer function is a part of the closed-loop transfer function, which can be used to help judge whether the closed-loop transfer function is stable or not. The open-loop transfer function is a bridge to study the closed-loop characteristics of the system.
Transfer function refers to the ratio of Laplace transform (or Z transform) of response (i.e. output) to Laplace transform of excitation (i.e. input) of linear system under zero initial condition. Let G(s)=Y(s)/U(s), where Y(s) and U(s) are Laplace transforms of output and input respectively.
Transfer function is one of the basic mathematical tools to describe the dynamic characteristics of linear systems. The main research methods of classical control theory-frequency response method and root locus method-are based on transfer function. Transfer function is one of the main tools to study classical control theory.
References:
Baidu encyclopedia? Transfer function? Open loop transfer function