The expected answers were: |
|
(a) |
(i) |
First half cycle |
|
|
|
|
|
|
C1 |
D2 |
|
|
|
~- |
|
|
|
|
|
|
|
|
) |
|
C2 |
|
|
|
+ |
|
(ii) |
Second half cycle |
|
C1
C2
+
(b) (i) Functions of passive components - C1,C2 and transformer.
Transformer steps (up or down) the input voltage to the required
value. C1 and C2 store charges to maintain Vpeak during conducting
half cycle of D1 and D2 and discharge the charge during the non-
conducting half cycle.
(ii) Active components
D1 and D2 conduct alternate half cycle and charge C1 or C2 to
produce required Va.
As reported, very few candidates who attempted it gave poor responses
suggesting ill-preparation. The question was on Power Supply. The
question was unpopular and candidates performed poorly in it.