The document analyzes the conduction modes and efficiency of buck-boost, buck, and boost power converters. Simulation results show that continuous conduction mode (CCM) has the highest efficiency for all three converters. For a given duty cycle, increasing the inductor value decreases the peak-to-peak ripple. The conduction mode can also be varied by keeping the inductance constant and changing the duty cycle, which keeps the ripple value the same. Therefore, the filter is designed for a specific inductance value. Tables of results are presented comparing efficiency for different conduction modes under varying duty cycles and inductance values.

1. ADVANCE POWER ELCTRONICS
Power Converters Report
COMSATS INSTITUTE OF INFORMATION & TECHNOLOGY, ABBOTABAD
PREPARED BY:
ZUNAIB ALI FA13-R09-013
DEPTT: ELECTRICAL ENGINEERING (POWER)

2. Power Converters
Note:
 All simulation results are taken by using mosfet at frequency of
Buck BOOST CONVERTER
Table 1: Conduction Mode & Efficiency For Different values of duty cycle of Buck-Boost Converter
For Constant Duty Cycle,
Inductance Value
Condition Mode
Efficiency,
DCM
50.71%
BCM
57.02%
CCM
57.53%
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3. Inductor Current vs. Gate Signal Figures for Buck-Boost Converter
Figure 1: For D=50%, DCM (BUCK BOOST)
Figure 2: For D=50%, BCM ( BUCK BOOST)

4. Figure 3: For D=50%, L=130μH CCM (BUCK BOOST)
Table 2: Conduction Mode & Efficiency For Different values of duty cycle of Buck-Boost Converter
For Constant Inductance,
Inductance Value
Condition Mode
Efficiency,
DCM
49.47%
BCM
51.99%
CCM
52.33%
Conclusion:
 By increasing the value of inductor the peal to peak value of ripple decreased.
 Efficiency of converter is maximum in continuous conduction mode.
 Conduction modes can be varied by keeping inductance constant and changing duty cycle, there by ripple value remains the same. Hence filter is designed for specific value.

5. Buck CONVERTER
Table 3: Conduction Mode & Efficiency For Different values of Inductance of Buck Converter
For Constant Duty Cycle,
Inductance Value
Condition Mode
Efficiency,
DCM
62.27%
BCM
64.78%
CCM
66.56%
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6. Inductor Current vs. Gate Signal Figures for Buck Converter
Figure 4: For D=50%, BCM (BUCK)
Figure 5: For D=50%, L=90μH DCM (BUCK)

7. Figure 6: For D=50%, L=110μH CCM (BUCK)
Table 4: Conduction Mode & Efficiency For Different values of duty cycle of Buck Converter
For Constant Inductance,
Inductance Value
Condition Mode
Efficiency,
DCM
63.29%
BCM
64.78%
CCM
65.45%
Conclusion:
 By increasing the value of inductor the peal to peak value of ripple decreased.
 Efficiency of converter is maximum in continuous conduction mode.
 Conduction modes can be varied by keeping inductance constant and changing duty cycle, there by ripple value remains the same. Hence filter is designed for specific value.

8. Boost CONVERTER
Table 5: Conduction Mode & Efficiency For Different values of Inductance of Boost Converter
For Constant Duty Cycle,
Inductance Value
Condition Mode
Efficiency,
DCM
74.91%
BCM
76.47%
CCM
79.28%
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9. Inductor Current vs. Gate Signal Figures for Buck Converter
Figure 7: For D=50%, L=338μH DCM (BOOST)
Figure 8: For D=50%, L=340μH BCM (BOOST)

10. Figure 9: For D=50%, L=380μH DCM (BOOST)
Table 6: Conduction Mode & Efficiency For Different values of duty cycle of Boost Converter
For Constant Inductance,
Inductance Value
Condition Mode
Efficiency,
DCM
73.11%
BCM
75.21%
CCM
76.96%
Conclusion:
 By increasing the value of inductor the peal to peak value of ripple decreased.
 Efficiency of converter is maximum in continuous conduction mode.
 Conduction modes can be varied by keeping inductance constant and changing duty cycle, there by ripple value remains the same. Hence filter is designed for specific value.