Rectifiers with Capacitor-Input Filters

When the filter has no reactor between rectifier and first capacitor, rectifier current is not continuous throughout each cycle and the rectified wave form changes. During the voltage peaks of each cycle, the capacitor charges and draws current from the rectifier. During the rest of the time, no current is drawn from the rectifier, and the capacitor discharges into the load.

Fig. 1 Voltage and current comparisons in reactor-input and capacitor-input circuits