Page 204 - Power Electronics Handbook

Unidirectional converters 195
v~ 'Y v~ 'R ,Controlled
thyristor output
, I , I ,
I , I I , , I 1 '
\I ,I \ I
\I \I \I \I
A Uncontrolled
, -/ 0"\,-,"'\.-,' 'x-,'~\\,-/ diode output
Load voltage
-7
Mqan d.c.
Supply voltage
Supply current

Fundamental
supply currrent
(a) a=Oo

thyristor voltage
.-, uncontrolled
-< Load voltage
diode voltage

Mean d.c.

Supply voltage
Supply current
--Id-
supply currrent
(b) O0<a<9O0

Load voltage

(c) 90°<ac1800
Pigure 9.19 Circuit waveforms for a three-pulse unidirectional converter