How Class A Chopper Work? Class A Chopper Operation Tutorial
Class A chopper is a step down chopper in which power is always flow from source to load. This Chopper is first quadrant chopper.
How Class A Chopper Work? Class A Chopper Operation Tutorial


When we plot a  graph of voltage and current  of class A chopper it will be in 1st quadrant .Hence it is also called 1st quadrant chopper

How Class A Chopper Work? Class A Chopper Operation Tutorial


  • In a Class A Chopper we used  input using a supply voltage (Vs)
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  • We Can also use high speed  semi-conductor like SCR IGBT etc.

  • A Free wheeling diode is used in a class a chopper

  • And in load side we used a inductor(L) and Load Resistance(RL) to get our output

OPERATION OF CHOPPER


Mode I ( When Chopper is ON)


How Class A Chopper Work? Class A Chopper Operation Tutorial
  • In mode (I) When chopper is on in this mode Supply Voltage is directly connected to the load side.

  • And in this mode Free wheeling diode(FD) will be in  reverse biased diode.

  • The Inductor (L) of load side will start charging with polarity Positive(+ve) and NeNegive(-ve)

  • Output across voltage will equal to supply voltage and direction of the current is showing in the fig with arrow line.

Mode II (When CHOPPER IS OFF)



  • In this mode chopper is off  so input is not connected with load side

  • At this time Free Wheeling Diode(FD)  will conduct  and inductor will discharge due to this inductor will change their polarity.

  • So in Both Case (Mode I& II )  current will remain same. and we get (+ve) Voltage and current .It means our device in working in first quadrant.