Page 241 - Power Electronics Handbook

Cycloconvetter circuits 23 1

transformer has also been appreciably reduced. Furthermore, it is now
difficult to maintain a balanced supply to the three-phase load. In spite of
this, the system is often economical to use in low-power circuits, where
good performance is not a prime criterion. Figure 10.12 shows an
alternative form of asymmetrical six-pulse converter, which consists of a
ring arrangement of bi-directional a.c. to d.c. converters and is therefore
not made from basic single-phase cycloconverter modules. As is seen, the
component content has been reduced by 50% over comparable

3 phase
a.c. supply

J
Three-phase load
Fi@Ke 10.12 Bridge six-pulse ring-type cydoconverter