Process control system using a control strategy implemented in a layered hierarchy of control modules

摘要

A process controller implements an overall, user-developed control strategy in a process control network that includes distributed controller and field devices. A user defines a module control strategy by specifying function blocks that make up control modules and determine the control strategy. The user modifies or debugs a module control strategy by adding, modifying and deleting function blocks, configuring parameters associated with the function blocks and creating a view to new attributes. By defining function blocks and control modules, a user-defined control strategy, application program or diagnostic program is represented as a set of layers of interconnected control objects identified as modules. A layer of the control strategy includes a set of modules which are interconnected in a user-specified manner. A module typically includes an algorithm for performing a specific function and display components which are used to display information to a user. A module is optionally represented to include a set of input and output connections for connecting to other modules. A module may be considered to be a "black box" which performs a specified function and is connected to other modules via specified input and output connections.