Almost all power regulators (including AC/AC, AC/DC, DC/DC and DC/AC regulators, etc.) use a closed loop feedback topology to ensure that the output of power can still meet expectations when the circuit, load or other factors change. Or experienced system designers know that reliable power supply is the basis of the overall reliability of the product, because it can protect the circuit from various faults caused by intermittent power supply.
Traditionally, closed loops can be achieved entirely through analog circuits. Power line designers have not only successfully developed novel, clever analog closed circuits that meet a wide range of input/output requirements, but they have also enabled the product to meet other priorities such as low noise, good transient response, power factor correction (PFC), and efficiency. To adopt such a topology, the designer needs to have a deep understanding of the first, second and even third level characteristics of the active and passive components in the design scheme.As far as power regulators are concerned, it is well known that there is a long way to go to turn good principles into good physics.
By changing the IGBT software in the control converter, the same hardware design can be used to output not only the square wave AC power supply with high distortion and high efficiency, but also the AC power supply with low distortion and low efficiency which is closer to the sine wave (provided by international rectifier company).
But the digital wind is sweeping across the power sector and breaking the norm. As can be seen from a number of recent product releases, practical closed loops are moving in the digital direction. As always, technology trends that begin with discrete components with larger and more expensive designs tend to extend to entire modules and even integrated circuits.