| 摘要 |
PROBLEM TO BE SOLVED: To provide a power-factor improvement circuit having long instantaneous-stop compensation time and reduced power loss.SOLUTION: A first step-up converter includes a first inductor L1, a first diode D1, and a first switching element Q1. A second step-up converter includes a second inductor L2, a second diode D2, and a second switching element Q2. A first capacitor C1 is connected between an output terminal of the first step-up converter and the second step-up converter and the ground. A second capacitor C2 is connected between the output terminal of the first step-up converter and the second step-up converter and the ground. A third switching element Q3 is connected in parallel to the second diode D2. A fourth switching element Q4 is connected between a positive-side terminal of the first capacitor C1 and a positive-side terminal of the capacitor C2. A control circuit 32 controls the first switching element Q1, the second switching element Q2, the third switching element Q3, and the fourth switching element Q4. |
