Distributed Control Logic Across I/O Modules for Low-Latency Process Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional industrial control systems face latency issues due to centralized control logic architectures, which degrade performance as the number of I/O points and logic size increase, leading to sluggish responses in process controllers, especially in applications requiring short latency.
Innovation Solution
Implementing a multi-layered control logic execution system where control logic is distributed across process controller and I/O module levels, using universal I/O modules that support various input/output types, allowing control logic to execute and exchange data in a distributed fashion, thereby reducing latency and supporting a large number of I/O points.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If control logic is centralized in process controllers, then system architecture is simple, but latency increases and response becomes sluggish
Solution Approach 1:
The control logic is segmented and distributed across multiple levels: process controllers at the upper level and I/O modules at the lower level. This segmentation allows critical control functions to execute closer to the data source, reducing latency while maintaining manageable complexity through modular architecture
Solution Approach 2:
The system transitions from a single-level centralized architecture to a multi-level hierarchical architecture. By adding the vertical dimension of control levels (process controller level vs. I/O module level), the system achieves both low latency for critical functions and architectural simplicity through standardized interfaces
2Loss of time
If control logic is moved to I/O modules, then latency is reduced, but scope of I/O connectivity and process control is limited
Solution Approach 1:
I/O modules are designed with universal functionality to execute multiple types of control logic (sequential control, batch control, continuous control) and support various I/O connectivity types. This universality allows reduced latency through local execution while maintaining broad adaptability through a single versatile platform
3Adaptability or versatility
If number of I/O points and logic size are increased in centralized architecture, then control scope is expanded, but latency performance degrades
Solution Approach 1:
As the number of I/O points and logic size increase, the control logic is automatically segmented and distributed to appropriate I/O modules. This segmentation prevents centralized processing bottlenecks, allowing the system to expand I/O capacity and logic complexity without degrading latency performance
4Loss of time
If all control strategies draw equally on computing resources in centralized architecture, then resource allocation is simple, but latency is increased for non-critical strategies
Solution Approach 1:
Different control strategies are assigned to different levels based on their latency requirements. Critical real-time strategies execute at the I/O module level with local quality prioritized for speed, while non-critical strategies execute at the process controller level. This creates differentiated resource allocation that optimizes latency for critical functions without complex centralized scheduling
Data Source
AI summary
A process control system includes a process controller level including at least one process controller, and an input/output (I/O) module level including at least one I/O module. The process controller level and the I/O module level are communicatively coupled. and each include control logic comprising control hardware or algorithm blocks. The control logic in the process controller level and the I/O module level are configured to execute and exchange data to perform process control for a process run by the process control system in a distributed fashion across the process controller level and the I/O module level.