We all know that a chopper definition can operate in any of the four quadrants by an appropriate arrangement of semiconductor devices. This characteristic of their operation in any four quadrants form the basis of their classification as class A, class B, class C, Class D, class E, etc.
It is observed that the chopper circuit of the figure also types A chopper.
It is observed that the chopper circuit of the figure also types A chopper.
- When the chopper is on V0 = Vs and current i0 flows from in the arrow direction shown.
- When the chopper is in off V0=0 and i0 in the load continues flowing in the same direction through freewheeling diode FD, shown in the figure.
- It is thus seen that the average values of both load voltage and current V0 and I0 are always positive.
- And this shown by the second figure by the hatched area in the first quadrant of V0 - I0 plane in the figure.
- The power flow in type A chopper is always from the source side to load side. This chopper is also known as the step-down chopper as average output voltage V0 is always less than the input dc voltage Vs.
