对于如图线性系统，应用拉式变换终值定理，可以很容易求出系统给定稳态误差ess=lim e(t) (t-无穷大)=limsE(s)(s-0)=limS(R(S)-C(S))= limS(R(S)-W(S)*R(S))= limsR(s)(1-Wb(s))其中Wb(s)= W(S)/(1+H W(S))在Matlab中，用函数dcgain可求得系统给定稳态误差Dcg=dcgain(nu