| 摘要 |
PURPOSE:To enhance safety of the apparatus through rapid detection of oscillation phenomenon by detecting the oscillation phenomenon of the current control system with a comparing means to count the oscillation frequency within a unit time with a counter and by judging transmission when it exceeds a prescribed value. CONSTITUTION:A comparator 53 compares reference voltage 52 to judge oscillation situations with current command 33 to output the result of judgment, and a counter 54 counts the output of the comparator 53 to output the result of counting successively to a judgment circuit 56: this circuit judges whether or not count quantities at fixed intervals given by, a timer 55 are over prescribed quantities. When the result of counting of the counter 54 by the timer 55 within a predetermined period of time is over a prescribed value, the judgment circuit 56 outputs it to a base drive circuit 38 to interrupt power supply. |
