| 摘要 |
Provided is a technique for reducing the power capacity required by a charge/discharge circuit. A converter (3) performs full-wave rectification of a single-phase AC voltage (Vin) and outputs a rectified voltage (Vrec) between DC power supply lines (LL, LH). An inverter (5) receives the rectified voltage (Vrec) and supplies three-phase AC current (Iu, Iv, Iw) to an inductive load (6). A charge/discharge circuit (4) is connected between the DC power supply lines (LL, LH). The charge/discharge circuit (4) has a buffer circuit (4a) and a booster circuit (4b). The buffer circuit (4a) includes a serial connection between a capacitor (C4) and a switch (Sc). The booster circuit (4b) comprises, for example, a boost chopper and includes a switch (SI), a reactor (L4), and a diode (D40). The charge/discharge circuit (4) transfers some of the pulse of the power input to the converter (3), between the DC power supply lines (LL, LH). |
