Page 200 - Power Electronics Handbook
P. 200
Unidirectional converters 191
Load voltage
Load voltage
Rpre 9.15 Bridge two-puk ddirrctional converters
removed, say from TH2, then at time tl this thyristor will go off and, since
none of the thyristors are refired, the load current will free-wheel in diode
D3 until it decays to zero.
An alternative system to Figure 9.15(c), which overcomes the
half-waving effect and so gives a controller with a greater response speed,
is shown in Figure 9.15(d), in which the number of devices have not been
increased but they have been rearranged so that D1 and Dz give a
