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Power Electronics Lecture (5). Prof. Mohammed Zeki Khedher Department of Electrical Engineering University of Jordan. 1. Diode Circuits or Uncontrolled Rectifier. Rectification: The process of converting the alternating voltages and currents to direct currents.
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Power ElectronicsLecture (5) Prof. Mohammed Zeki Khedher Department ofElectrical Engineering University of Jordan 1
Diode Circuits or Uncontrolled Rectifier Rectification: The process of converting the alternating voltages and currents to direct currents
Performance Parameters rectification effeciency form factor ripple factor
Transformer Utilization Factor • TUF = Pdc/VsIs
Crest Factor CF = Is-peak/ Is
Example 1: The rectifier shown in Figure has a pure resistive load of R Determine (a) The efficiency, (b) Form factor (c) Ripple factor (d) Peak inverse voltage (PIV) of diode D1. . It is clear from the Figure that the PIV is
VA = VsIs = 0.707 Vm x 0.5 Vm /R • TUF = Pdc/VsIs = (0.318)2 / (0.707 x 0.5) = 0.286 • CF = Is-peak/ Is = 1/0.5 =2 • PF = Pac/VA = 0.52 / (0.707X0.5) = 0.707
The main disadvantages of half wave rectifier are: High ripple factor, Low rectification efficiency, Low transformer utilization factor, and, DC saturation of transformer secondary winding.