3.4.Three Phase RectifiersThree-phase rectifiers are classified into Half-wave, and Full-wave energized loads with various impedances and back emf. Applying three-phase rectifiers aims to realize smooth rectified voltage, increasing efficiency, utilization , and minimizing the parameters of the filter.3.4.1: Three-Phase Half-Wave RectifierFigure 3.9-a illustrates three-phase half wave rectifier energized R load, where three diodes ( D1, D2, and D3) operates in series sequence, each one for a time of 120°. The operation sequence is determined by the criteria : " the diode with maximum positive voltage applied across it's terminals will conduct " , therefore each phase will pass the current for 120°, where for the rest of time this phase will be off and doesn't participate in the rectification process. Fig.3.9-a: Three-phase half-wave rectifier- Wye connectedCHAPTER THREEDIODE RECTIFIERS
Fig.3.9-b: Three-phase voltage, and output rectified voltage.Fig.3.9-c: Phase current, and instantaneous rectified current.