ECE 312 - Industrial Electronics

The boundary between continuous conduction mode (CCM) and DCM is determined by

• The load resistance and inductance

• The switching frequency and input voltage

• The inductor current reaching zero

• The size of the output capacitor

Why is DCM preferred in certain applications?

• It allows for higher efficiency at low load conditions

• It minimizes inductor size

• It eliminates the need for diodes in the circuit

• It increases the switching frequency

What happens to the peak inductor current in DCM as the load resistance increases?

• It remains constant

• It increases proportionally

• It decreases

• It oscillates around a fixed value

Which of the following parameters primarily influences the duration of the zero-current interval in DCM?

• Switching frequency

• Inductor value and load resistance

• Input voltage

• Output capacitance

In a converter operating in DCM, the duration of the zero-current interval is directly proportional to

• The switching period

• The load resistance

• The square of the duty cycle

• The peak inductor current

For converters operating in DCM, which factor is responsible for higher output voltage ripple?

• Low switching frequency

• Zero-current intervals

• High load resistance

• Reduced inductance

When transitioning from CCM to DCM, what happens to the relationship between the duty cycle and the output voltage?

• It becomes non-linear

• It remains proportional

• It becomes independent of load resistance

• It follows an exponential relationship

What happens to the inductor current waveform as the load decreases in DCM?

• The peak current increases

• The zero-current interval increases

• The current waveform becomes continuous

• The duty cycle increases

What is the origin of the Discontinuous Conduction Mode (DCM) in power converters?

• When the inductor current reaches zero during the off-state

• When the duty cycle exceeds 100%

• When the switching frequency is very high

• When the capacitor voltage drops to zero

What is a key feature of DCM operation?

• Continuous inductor current

• Pulsating output voltage

• Zero inductor current for part of the switching cycle

• Increased ripple in the input current