Assume a Flyback converter that is operating in the DCM. Which of the following can change the operation to the CCM?Question 8Select one:a.Increasing the transformer turn ratiob.decreasing the magnetising inductance c.decreasing the switching frequency d.decreasing the output resistance
Question
Assume a Flyback converter that is operating in the DCM. Which of the following can change the operation to the CCM?Question 8Select one:a.Increasing the transformer turn ratiob.decreasing the magnetising inductance c.decreasing the switching frequency d.decreasing the output resistance
Solution
The operation of a Flyback converter can be changed from Discontinuous Conduction Mode (DCM) to Continuous Conduction Mode (CCM) by:
a. Increasing the transformer turn ratio: This will not change the operation to CCM. The transformer turn ratio mainly affects the voltage gain but not the conduction mode.
b. Decreasing the magnetising inductance: This can change the operation to CCM. Lower inductance will allow the current to rise more quickly, which can lead to a continuous current, hence changing the operation to CCM.
c. Decreasing the switching frequency: This can also change the operation to CCM. Lower switching frequency means longer time for each cycle, which can allow the current to continue flowing, hence changing the operation to CCM.
d. Decreasing the output resistance: This will not change the operation to CCM. The output resistance mainly affects the load current but not the conduction mode.
So, the correct answers are b and c.
Similar Questions
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