| 摘要 |
PURPOSE:To prevent the generation of inrush currents when power return and start reoperation smoothly by inputting speed feedback signals, a level thereof is converted when detecting power stoppage, to a current controller. CONSTITUTION:Difference between a speed command 21 and the speed feedback signals 22 of a motor 6 is counted by means of a speed controller 8 and used as a current command 23, and difference between the command 23 and current feedback signals 24 is counted by means of a current controller 9 and used as pulse generator input 25. A level converting circuit 11 outputs signals 30 obtained by level-converting the speed feedback signals 22. A bias setting circuit 13 gives the current controller 9 signals 30 when power stoppage detecting signal 31 are output from a power- stoppage detecting circuit 12. Thus, the pulse generator input 25 does not differ markedly from a condition before power stoppage when power return, and inrush excessive currents are not generated when power return. |
