| 摘要 |
PURPOSE:To improve reliability and precision by calculating the correlation between a disturbance and a process output, and correcting a feedforward gain automatically. CONSTITUTION:The signal of a feedforward element 12 is added to the output signal of a feedback control system, and the resulting signal is inputted to the process 13 of a heat exchanger, etc. An arithmetic control part 17 receives the output Y of this process 13 and a disturbance X (output of delay element 16) to calculate the correlation between the both, and make a decision 18 on whether the feedforward gain Kf can be corrected or not. This is supplied to the feedforward element 12 to correct the feedforward gain Kf. If a disturbance D occures, the process output Y varies, and the extent of the correlation is therefore calculated as the correction term of the gain and a coefficient of correlation. A decision on the correlation extent between the both is made from the coefficient of correlation, and when there is some correlation, the gain Kf is corrected by the calculated correction term. |
