| 摘要 |
<p>In the inventive bi-directional DC-DC converter that uses a transformer for both step-down and step-up operations, a switching frequency for operating a switching device is set separately for the step-down and step-up operations. For example, when the switching frequency during the step-up operation is lower than the switching frequency during the step-down operation, the range in which the duty ratio in PWM control can be controlled is widened, compensating for step-up ratio insufficiency. Conversely, step-down ratio insufficiency is compensated for by making the switching frequency during the step-down operation lower than the switching frequency during the step-up operation.</p> |
