Page 1003 - Basic Electrical Engineering
P. 1003
Figure 14.39 Half-wave diode rectifier
Figure 14.40 (a) Half-wave-controlled rectifier circuit; (b) output voltage wave shape
Similar to a full-wave rectifier using diodes, we can have a full-wave-
controlled rectifier using more number of SCRs.
Single-phase full-wave-controlled bridge
For conversion of single-phase ac supply to a variable dc output across a
load, we can use an SCR bridge circuit using two SCRs and two diodes as
shown in Fig. 14.41. In the positive half cycle of the input ac supply, SCR T 1
and diode D will be conducting. In the negative half cycle of the input
1
voltage, diode D and SCR T will be conducting. The firing angle of both
2
1
the SCRs are controlled so that the average output voltage is variable dc.
