Method to control a process variable

US10407328B2 · kind B2 · utility

Assignee

• Endress+Hauser Conducta GmbH+Co. KG · DE

Inventors

• Thomas Alber · Stuttgart, DE
• Christoph Herb · Wiernsheim, DE

Key dates

• Filing date: Dec 14, 2015
• Grant date: Sep 10, 2019
• Expiry date: Oct 16, 2037

Classification

• Technology area (CPC G): Physics
• CPC primary: G05B2219/25276
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

A method to control a process variable in a process by means of a control unit comprises: sequential determination of values of a reference variable to be supplied to the first control unit based on the values of a first measurand; sequential determination of values of a regulating variable using both values for the reference variable and sequentially determined values for the process variable; with a current value for the reference variable being determined: by sequentially saving values of the first measurand, or values derived therefrom, in a first FIFO memory having a number K of memory locations for saving one value respectively, namely a memory featuring a number K of logically consecutive memory locations (j=i) in such a way that the oldest of the values saved in the first FIFO memory is saved in a first memory location (j=1) and the value saved last in the first FIFO memory is saved in a final memory location (j=k); and by using only the n oldest values saved in the first FIFO memory to determine the current value for the reference variable, with n being a number of values that is smaller than the number K of the values saved in the memory locations of the first FIFO memory…