| 摘要 |
PROBLEM TO BE SOLVED: To provide a power conversion device capable of certainly fusing a conventionally-equipped overcurrent breaking circuit protection element, which is not fused by a short circuit current of a constant current source that is an input power supply, by a simple configuration, in occurrence of abnormalities such as overvoltage and overcurrent, without using a DC circuit breaker and without providing a new DC power supply nor a new protection circuit.SOLUTION: A control circuit makes a protection operation switching element be in an on state for a predetermined time period when generation of overvoltage or overcurrent is notified. Then, electric charge stored in a capacitor is circulated and discharged while passing through the capacitor, an overcurrent breaking circuit protection element, the protection operation switching element, and the capacitor, in this order. Since the discharge current can be set to current large enough to fuse the overcurrent breaking circuit protection element that is not fused by a short circuit current of a DC power supply, the overcurrent breaking circuit protection element can be fused with certainty. Thereby, a highly-reliable power conversion device can be obtained at a low cost. |
