| 摘要 |
The invention relates to a method and a system for determining hysteresis of a process device in a process environment. The process comprises collecting ( 50 ) second-level sample data ys and us from control and measurement signals u and y of a control circuit. Minute mean values y(min) and u(min), which are stored in a database ( 52 ), are calculated from these second-level measurement values. The pairs suitable for hysteresis calculation are selected from the minute-level sample pairs um and ym according to a certain procedure. The pairs are also divided into two groups. Unsuitable pairs are rejected ( 57 ). Two characteristic curves ( 54 ) are calculated from the selected pairs (um, ym) for hysteresis calculation ( 55 ). The calculation ( 55 ) also includes a routine which evaluates the reliability of the identified hysteresis. |
