| 摘要 |
PURPOSE:To operate a synchronous motor smoothly by operating the difference between previous and current speed command values, then obtaining the number of times of the speed control loop operation where a speed command is executed during the same time interval and calculating the distributed value of speed command value. CONSTITUTION:Moving amount of a synchronous motor SM1 is counted based on the output from an incremental rotary encoder RE2 coupled with the SM1, then it is fed to a CPU10. The CPU10 receives a speed command N0 from a host CPU9 and controls an inverter circuit 13 to drive the SM1. Then a difference N between previous speed command value N0-1 and current command value N0 is obtained. The number of times of operation, M, of a speed operating loop executed during such interval as the difference N is zero is determined based on the difference of a counter 3 thus determining the distributed value n0 of the variation of speed command according to a formula n0=N/M. By such arrangement, smooth rotation is realized, without requiring modification of program, even if the time interval of the variation of speed command signal is not constant. |
