Process Control Module Interconnection via Unidirectional Lines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Industrial process control systems require flexible configuration options for varying levels of fault tolerance, as existing methods like Triple Modular Redundancy (TMR) are costly and inflexible, and hot-standby modules can cause system disruption during changeovers.
Innovation Solution
A distributed industrial process control system with processors connected via interprocessor links and input/output modules using unidirectional command and response lines, allowing for flexible configuration and redundancy levels, with unique identifiers for module identification and HDLC/NRZI encoded frames for communication, enabling live system backplane insertion and online module replacement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Triple Modular Redundancy (TMR) is used to provide fault tolerance, then system reliability is improved, but system cost and complexity increase
Solution Approach 1:
The system dynamically configures redundancy levels based on operational requirements. Modules can be selectively enabled or disabled to provide TMR only when needed, rather than maintaining full TMR architecture always. This allows the system to adapt its complexity and redundancy level dynamically, resolving the contradiction between reliability and complexity.
Solution Approach 2:
The patent changes the parameter of redundancy level from a fixed architectural constraint to a configurable operational parameter. By allowing the system to adjust the degree of redundancy (from full TMR to partial or no redundancy) based on real-time requirements, the system can optimize the balance between reliability and complexity.
2Reliability
If hot-standby modules are used for fault tolerance, then system reliability is improved, but system operation is disrupted during module changeover
Solution Approach 1:
The system performs preliminary configuration and initialization of standby modules before they are needed. Modules are pre-configured with necessary parameters and identifiers, and the system maintains readiness states that allow for immediate failover without disruption. This preliminary preparation eliminates changeover time while maintaining reliability.
Solution Approach 2:
The patent ensures continuous system operation by implementing seamless module replacement mechanisms. When a module fails, the system continuously maintains operation through pre-configured standby modules that can take over immediately. The unidirectional command and response lines maintain continuous communication throughout the transition, ensuring no interruption in useful action.
3Reliability
If dedicated hardware and software test regimes are implemented for fast fault recognition, then system reliability is improved, but device complexity increases
Solution Approach 1:
The system implements self-diagnostic capabilities where modules automatically perform fault detection and reporting without external intervention. Each module monitors its own status and communicates fault conditions through the unidirectional response lines. This self-service approach provides fast fault recognition while minimizing the complexity of external test equipment and diagnostic software.
Solution Approach 2:
The patent incorporates continuous feedback mechanisms through unidirectional response lines that allow modules to report status and fault conditions back to the system. This feedback loop enables fast fault recognition through simple, dedicated communication paths rather than complex diagnostic routines, resolving the contradiction between reliability and complexity.
Data Source
AI summary
An industrial process control apparatus and method that includes a number of processors and a number of input/output modules. Each processor is connected to a plurality of the input/output modules by a unidirectional command line. Each input/output module is connected to a plurality of the processors by a unidirectional response line. The processors are arranged to issue an identifier request to all of the connected input/output modules and each input/output module is arranged to respond to the identifier request via the respective response line with a response that includes a unique identifier. Such a configuration allows each processor to identify the physical location of each respective input/output module.