FULL WAVE RECTIFIER BY JAYASRI.K(221710303019)

Full wave rectifiers have some fundamental advantages over their half  wave rectifier counter parts.The average DC output voltage is more than that of a half wave. The output of full wave rectifier has much less ripple than that of the half wave rectifier, producing a smoother output wave form.

The full wave rectifier consists of two power diodes connected to a single load resistance(Rl) with each diode taking in turn to supply current to the load. For the proper operation of the circuit,a center tap on the secondary winding of the transformer is essential .

It is noted that the load current flows in both the half cycles of AC voltage and in the same direction of the load resistance. Hence, we get rectified output across the load.The load current is sum of individual currents flowing in corresponding half cycles. It is also noted that the two diodes 

do not conduct simultaneously but, in alternate half cycles. Thus, the full wave rectifier circuit consists of two half wave rectifier circuits working independently of each other.

POSITIVE HALF CYCLE AND NEGATIVE HALF CYCLE:

During the negative half cycle of the supply diodes D3 and D4 conduct  in series,but diodes D1 and D2 switch off as they are now reverse biased.The current flowing through the load is the same direction as before. As the current flowing through the load is unidirectional, so the voltage developed across the losd is also unidirectional the same as for the previous two diode full-wave rectifier, therefore the average DC voltage across the load is 0.637 Vmax.