Multi-Layer Control Logic for Low-Latency Industrial I/O
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional process controllers in industrial control systems face latency issues, leading to sluggish responses, particularly in applications requiring short latency, such as factory automation and safety interlocks, due to the centralized architecture that degrades performance with increased I/O points and logic size.
Innovation Solution
The control logic is distributed across multiple levels, including a process controller level and an I/O module level, with universal I/O modules supporting various input/output types, allowing control logic to be executed closer to I/O points, thereby reducing latency and supporting a large number of I/O points while maintaining short response times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If control logic is centralized in process controllers, then system architecture is simple and I/O connectivity scope is limited, but latency increases and response becomes sluggish
Solution Approach 1:
The control logic is segmented into two distinct levels: process controller level and I/O module level. The I/O module executes control logic locally for fast response, while the process controller handles higher-level coordination. This segmentation reduces latency by enabling local decision-making at the I/O level without requiring centralized processing for all control decisions.
Solution Approach 2:
The patent introduces a vertical dimension to the control architecture by adding the I/O module level between the process controller and field devices. This creates a multi-layered hierarchy where control functions are distributed across different levels, enabling fast local responses while maintaining overall system coordination through the process controller.
2Speed
If control logic is moved to I/O modules to reduce latency, then response time improves, but I/O connectivity scope is limited and process control scope is reduced
Solution Approach 1:
The I/O module is designed with universal functionality to support multiple input/output types and execute various control logic functions locally. This multi-functionality enables the I/O module to handle diverse I/O connectivity requirements while maintaining fast response times through local control execution.
Solution Approach 2:
By segmenting control functions between the process controller and I/O module, the system achieves both fast local responses and broad I/O connectivity. The I/O module handles I/O-specific control tasks locally, while the process controller manages overall system coordination, enabling the system to scale to support a large number of I/O points.
3Device complexity
If centralized process controller architecture is used, then device complexity is low, but latency increases with increased I/O points and logic size
Solution Approach 1:
The control logic is segmented into two distinct levels: process controller level and I/O module level. The I/O module executes control logic locally for fast response, while the process controller handles higher-level coordination. This segmentation reduces latency by enabling local decision-making at the I/O level without requiring centralized processing for all control decisions.
Data Source
Figure 1
Figure 2
AI summary
A process control system (200) includes a process controller level (240) including at least one process controller (121, 122), and an input/output (I/O) module level (230) including at least one I/O module (231, 232, 233). The process controller level and the I/O module level are communicatively coupled and each include control logic comprising control hardware or algorithm blocks (120a, 120b, and 235a, 235b, 235c). 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.