Optimum Design
T
R
Figure 3.1 Model for power transmission.
151
Ro-internal resistance of the generator plus the leads.
Criterion function
PR = 12R
Functional constraint
I- Eg
Ro+R
Substituting for I
p_ E2g
R
(Ro "-[- R) 2
~=dP [.(Ro+R)2-R[2(Ro+R)]IE2g~R~_~ £
=0
dP
(Ro + R)
= 0 = E~
[(Ro + R) 2R]
R) 4
+
or R=Ro
which says 50% efficiency but maximum delivery of power. This is not practical from a cost basis, however; the communication engineer must deliver
maximum power.
There is also another method for using functional constraints with a
criterion function.
T
R
Figure 3.1 Model for power transmission.
151
Ro-internal resistance of the generator plus the leads.
Criterion function
PR = 12R
Functional constraint
I- Eg
Ro+R
Substituting for I
p_ E2g
R
(Ro "-[- R) 2
~=dP [.(Ro+R)2-R[2(Ro+R)]IE2g~R~_~ £
=0
dP
(Ro + R)
= 0 = E~
[(Ro + R) 2R]
R) 4
+
or R=Ro
which says 50% efficiency but maximum delivery of power. This is not practical from a cost basis, however; the communication engineer must deliver
maximum power.
There is also another method for using functional constraints with a
criterion function.