| 摘要 |
PURPOSE:To conduct a high conformity and high accuracy inverter control without using a mean value detecting filter by comparing an instantaneous value including a detection value ripple with a controlled variable set point through an ON-OFF binary output comparator. CONSTITUTION:An instantaneous value comparison circuit 1a compares the instantaneous value S4 of a controlled variable detection signal with a controlled variable set point S8, and the results of such comparison are respectively formed as 2 sets of ON-OFF binary signals S6. An arithmetic circuit 1b judges the contents of control according as the number of times of the continuous ON-state of a pulse train obtained by the logical product operation of said signal S6 and a scanning pulse with an appropriate period is more than a prescribed number of times or not. When the number of times of the continuous ON of said pulse train exceeds the prescribed number of times and the relation between said signals S8 and S4 is S8>S4, said controlled variable is increased, and said variable is decreased in case of S8<S4; and any of said increase or decrease is not done if the number of times of the continuous ON is less than the prescribed number of times. |
