Why use half wave rectification and what are its advantages over full wave rectification?

Answer 1

A full-wave rectifier will provide an output through both the positive and negative halves of the AC sine wave. The half-wave rectifier will only provide an output for half the cycle. The filtered outputs of both rectifiers can be "smoothed" well, but the higher the load on the half-wave rectifier, the more the output voltage will vary across a cycle of input power. This results in higher ripple and makes regulation a bit more difficult. The full-wave rectifier will provide an output through both the positive and negative halves of the sine wave. It effectively "inverts" the negative half of the cycle and provides two "pulses" of power per cycle as opposed to one pulse per cycle for the half-wave rectifier. The full-wave rectifier might use a pair of diodes and a center tapped transformer, or might use four diodes in a full wave bridge configuration and a transformer with no center tap.

Answer 2

A bridge rectifier and a full-wave rectifier? The full-wave rectifier requires half as many diodes but needs a center-tapped transformer and delivers half the transformer's voltage. If you need 12 volts out of the power supply, using a full-wave rectifier will require you to use a 24-volt transformer. The bridge rectifier allows you to get full transformer voltage out of the power supply. If you need 12 volts out of the supply, you can get it with a bridge rectifier and a 12-volt transformer. (However, given this you NEVER get full secondary voltage out of a power supply. There are voltage drops across the diodes, and usually you'll throw a voltage regulator in there which cuts the final voltage even farther. Still, though, you need a smaller, less expensive transformer to get a certain voltage out of a bridge-rectified supply than out of a full-wave-rectified supply. It's much cheaper to use more diodes than more transformer to get to the same place, so that's what everyone does.)

Answer 3

Half rectifiers allow half the ac wave through. This is usually done with a rectifier diode. A full wave rectifier rectifies the ac sinusoidal wave but allows all of the power through. This is usually done by a rectifying circuit of four diodes. To picture the result of a half wave rectification just erase the lower parts of the sinusoidal ac wave. To picture the result of a full wave rectification erase the lower parts of the wave and then redraw them inverted, ie above the center line.

Answer 4

Depending on the circuit being driven, full wave rectification may be unnecessary, and requires more parts, so half wave rectification takes up less physical space, and costs less to build.