Active rectification

It is frequently used for arrays of photovoltaic panels to avoid reverse current flow that can cause overheating with partial shading while giving minimum power loss.

However, even Schottky rectifiers can be significantly more lossy than the synchronous type, notably at high currents and low voltages.

The voltage drop across the transistor is then much lower, causing a reduction in power loss and a gain in efficiency.

Active rectifiers also clearly still need the smoothing capacitors present in passive examples to provide smoother power than rectification does alone.

Using active rectification to implement AC/DC conversion allows a design to undergo further improvements (with more complexity) to achieve an active power factor correction, which forces the current waveform of the AC source to follow the voltage waveform, eliminating reactive currents and allowing the total system to achieve greater efficiency.