| 摘要 |
<P>PROBLEM TO BE SOLVED: To carry out switching of a drive system without having to use a bidirectional switch. <P>SOLUTION: An inverter device includes a connection switch 13 that connects/disconnects the junction point WP of leg L3 and an intermediate potential point NP; an inverter controlling means 23 that controls the switching operation of the switching elements of each leg; and a switching control means 21 that controls the operation of the connection switch. The connection switch includes a parallel-connected mechanical switch SK and a semiconductor switch SH that is out of conduction or can be brought into conduction in a single direction. The switching control means causes the mechanical switch to provide/remove continuity, only when the semiconductor switch is conducting in a single direction. When the switching elements S5, S6 of leg L3 are brought out of conduction, the switching control means synchronizes the mechanical switch with transition, from a state in which the semiconductor switch SH goes out of conduction state to a state in which it is conducting in a single state. When the switching elements of leg L3 are complementarily brought into conductive state, the switching control means synchronizes the mechanical switch with transition from a state, in which the semiconductor switch SH is conducting in a single direction to a state in which it is out of conduction. <P>COPYRIGHT: (C)2008,JPO&INPIT |
