POWER SUPPLIERS

A power supply is used to  energize and  control  the electronic  system. The  power  supply converts AC voltage  into revaluated DC  voltage  according  to the requirement  of particular system. Since  the rectifier also performs this operation but the DC  output  will not be  ripple less  hence  the filter circuit is used to obtain  ripple less DC  voltage. The  filter circuit makes the rectifier inefficient and weighty because physically the filter circuit is quite large. Therefore  a switched mode   power supply  is used to convert AC into  very high  fleered DC. SMPS   is based on the principle  of chopper.

Chopper is a device  which  converts a fixed  dc voltage  to a variable de voltage. Chopper  provides  smooth  acceleration control fast response regeneration and high efficiency choppers are used in subway cars trolley buses  marine hoists forklift trucks  and mine haulers.