Forward converter

A type of non-resonant converter. It uses multiple switching devices, employs a separately excited oscillation method, and adopts a PWM control method. It is an isolated converter with a transformer between the primary and secondary sides. It is mainly used as an AC-DC converter. Its structure is an isolated version of a buck converter with a transformer between the primary and secondary sides. The basic operation is the same as that of a buck converter, maintaining a constant output voltage by varying the pulse width in response to fluctuations in the input voltage. On the secondary side, the output voltage is rectified to its average value by a choke coil. It can also be considered a structure in which a choke coil is added to a flyback converter. Although many windings are required, it offers high efficiency and relatively good high-frequency switching characteristics. Since 1 transformer is incorporated, it can output a voltage higher than the input voltage by stepping up according to the turns ratio. When the switch is turned off, a large kickback voltage is applied to the switch, so it is necessary to use a transformer snubber or similar circuit to suppress the voltage applied to the switch below its withstand voltage. It is widely used as a power supply ranging from small to large capacity in general electrical and electronic equipment that requires more power than flyback converters.