Environmental Engineering Reference
In-Depth Information
The final closed loop gain expression is obtained by substituting
,
and
into the Rosenstark relationship (3.7), which gives
In the case we want to apply the Choma method, according to Section 3.4
we have to evaluate the null return ratio, instead of the asymptotic gain,
In particular, consider again the AC schematic diagram in Fig. 6.4 in
which the input voltage source has not been nullified, as shown in Fig. 6.7a.
Since we must consider the output voltage to be zero, all the current,
i
, of
the current generator (which replaces the critical controlled source) flows
trough resistance
and sets the voltage at node X 1 ,
to e
