A half wave rectifier is a circuit which allows only one (positive) half of the AC input waveform to pass through it. Thus converting the AC to DC.

The conduction takes place only in one half cycle of supply ‘m’ hence the name of this circuit is half wave rectifier. The output is suppressed in other half.

The circuit configuration of a half wave rectifier

T1 is the input step down transformer. RL is the load resistance. Let the resistance of the diode in the ON state be RF and let the resistance of the secondary winding be RS.

Operation of HWR:

During the operation in the positive half cycle of AC supply (0-π), the secondary voltage VAB is positive i.e. A is positive with respect to B. Hence the diode is forward biased and starts conducting.