| 摘要 |
PURPOSE:To surely detect single phase disconnection by comparing a dimensionless value proportional to the three-phase output current of an inverter with a dimensionless value proportional to a current command and detecting single phase disconnection. CONSTITUTION:Three-phase output from a rectifier 12 is fed to a divider 13. Output from the rectifier 12 is also fed to an average value circuit 14 which provides an output B to a divider 13. The divider 13 carries out operation of X=B/A and the operation result is fed to a comparator 15. A full-wave rectifier 16 receives current commands Iu, Iv, Iw and provides an output C to a divider 18. Output C from the rectifier 16 is also fed to an average value circuit 17 which provides an output D to a divider 18. The divider 18 performs operation of Y=D/C and provides the operation result to the comparator 15. If X<Y, the comparator 15 produces a single phase disconnection detection signal. |
