| 摘要 |
PURPOSE:To improve diagnosing speed for the normal/defective status of a control system by evaluating conrolling characteristics as a control loop by the size of squared integration value of a control deviation and then combining the coherence function of each element of the control system with a transmission function to evaluate the characteristics. CONSTITUTION:A controlling property as a control loop is evaluated by the squared integration value ISE of the control deviation (b). If the value of ISE exceeds reference value ISEo, some failure is supposed and an objective value (a) and a controplling variable (l) are analysed at the two-dimensional frequence by a two-dimensional frequency analizer 18 to find out the coherence function CFaI between both values (CFaI is found out by the formula in Table-1). If the coherence function CFaI is less than a reference value CFaIo, it is supposed that the control variable (l) is controlled by a factor other than the objective value (a), so that disturbance or a characteristic of each element is checked without considering the transmission function of the control variable (l) to the objective value (a). |
