| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a three-level power converter hardly causing the problem that an overvoltage destroys a flywheel diode by transiently applying a P-N DC voltage (2E(V)) to the flywheel diode of an intermediate potential C side self-extinguishing semiconductor device in blocking a gate. <P>SOLUTION: In the three-level power converter in which the self-extinguishing semiconductor devices 2a to 2h which include the flywheel diode as the power conversion element are used, junction capacitance of the flywheel diodes 3b, 3c, 3f, 3g undergoing a voltage which is higher than the intermediate potential makes equivalently larger than the junction capacitance of the other flywheel diodes 3a, 3d, 3e, 3h in blocking the gate of each self-extinguishing semiconductor device, thus the flywheel diode undergoing a voltage which is higher than the intermediate potential does not undergo a voltage which is higher than the intermediate potential. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
