With the advancement in the field of electronics the need of dc supplies increased .It was NASA in 1960 made SMPS.Subsequently due to it's light weight and compact size SMPS became popular .Now 70%-80% of production of power supplies is SMPS
There is a phase controlled rectifier to give a dc voltage .But why we use SMPS?.The ripples in DC should be minimum for better rectification.So filtering of ac must be efficient,therefore the filtering circuit must be a large /bulky LC filter.
SMPS works on principle of DC chopping.The output is varied by varying the duty cycle of chopper by PWM or FM technique .The circuit configuration are of four types,Fly back,push pull,half bridge and full bridge
For SMPS inverter PWM technique is used.The output is converted to dc by a diode rectifier .As inverter is allowed to operate at higher frequency.The ripples on dc can be filtered out by small L&C components.For power transistors chopping frequency is limited to 40KHZ ,power MOSFET 200KHZ .As frequency high low size needed .
There is a phase controlled rectifier to give a dc voltage .But why we use SMPS?.The ripples in DC should be minimum for better rectification.So filtering of ac must be efficient,therefore the filtering circuit must be a large /bulky LC filter.
SMPS works on principle of DC chopping.The output is varied by varying the duty cycle of chopper by PWM or FM technique .The circuit configuration are of four types,Fly back,push pull,half bridge and full bridge
For SMPS inverter PWM technique is used.The output is converted to dc by a diode rectifier .As inverter is allowed to operate at higher frequency.The ripples on dc can be filtered out by small L&C components.For power transistors chopping frequency is limited to 40KHZ ,power MOSFET 200KHZ .As frequency high low size needed .
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