Single-Phase Half-Wave Rectifier

Waveforms

Single-Phase Half-Wave Rectifier

Performance ParametersAverage value of the output voltage, VdcAverage value of the output current, IdcOutput dc power, PdcPdc = VdcIdcrms value of the output voltage, VrmsOutput ac power, PacPac = VrmsIrms

Performance Parameters (continued)Efficiency, = Pdc/PacEffective (rms) value of the ac component of the output voltage, VacVac = Vrms2 Vdc2Form factor, FFFF = Vrms/VdcRipple factor, RFRF = Vac/Vdc

Performance Parameters (continued)Alternate form for ripple factor

Transformer utilization factor, TUFTUF = Pdc/VsIsVs, Is are rms voltage and current of the transformer secondary

Input Voltage and Current

Performance Parameters (continued)Displacement angle, Displacement Factor, DFDF = cos()Harmonic Factor, HF

Performance Parameters (continued)Power Factor, PF

Performance Parameters (continued)Crest Factor, CF

Example 3.1Determine , FF, RF, TUF, PIV of the diode, CF of the input current, input PF.

Determine the Average Voltage, Vdc

Determine the rms Voltage, Vrms

Determine Pdc, Pac, and

Determine FF and RF

Determine the TUF

Determine the PIVPIV is the maximum (peak) voltage that appears across the diode when reverse biased. Here, PIV = Vm.

-++-PIV

Determine CF

Determine PF

Summary Half-Wave RectifierRF=121%HighEfficiency = 40.5LowTUF = 0.286Low1/TUF = 3.496transformer must be 3.496 times larger than when using a pure ac voltage source

Half-Wave Rectifier with R-L Load

Waveforms of Current and VoltageConduction period of D1 extends beyond t =

Average Output VoltageIncrease average voltage and current by making = 0

Waveforms with Dm installed

Application as a Battery ChargerDiode conducts for vs > E, starting when Vmsin = E

Waveforms for the Battery Charger

Diode turns off when vs < E (at = )Charging current io = (vs E)/Rio = (Vmsint E)/R for < t <

Single-Phase Full-Wave RectifierCenter-Tapped Transformer

Waveforms for the Full-Wave Rectifier

Single-Phase Full-Wave RectifierPIV = 2Vm

Full-Wave Bridge Rectifier

Waveforms for the Full-Wave Bridge

Full-Wave Bridge with WaveformsConduction patternD1 D2 D3 D4PIV = Vm

*********************************