The objective of any performance index is to evaluate quantitatively and qualitatively the operation of an equipment and allow comparisons to be made between various configurations. The most used indices for buck, boost, and buck/boost converters are presented in Table I. Half-bridge converters act as either buck or boost converters depending on their mode and share exact characteristics. For this reason, half-bridge indices are not included.
Performance Index | Expression | ||
---|---|---|---|
Buck | Boost | Buck-Boost | |
Duty cycle |
|
|
|
Transfer function |
|
|
|
Output current (A) |
|
|
|
Output voltage (V) |
|
|
|
Current ripple |
|
|
|
Voltage ripple |
|
|
|
Table 1: Performance Indices for dc-dc converters.