1) Voltage Follower Approach: Some converters designed
to work in discontinuous conduction mode are natural voltage
followers and the inner current loop can be removed [9]–[14].
This means a simplification of the control circuit. Sinusoidal
line current is maintained in converters such as buck-boost and
flyback, SEPIC, Cuk, and Zeta. Boost converter may be designed
for sinusoidal line current but forcing a high output voltage.
In general terms, this is a good option for medium and low
power applications (100 W–1 kW) because RMS currents cause
a penalty in the conduction losses. Other advantages may be obtained
such as the absence of losses due to the reverse recovery
of the boost diode. This fact allows the use of this circuit in
higher power applications.