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A new formal approach to safe response time upper bound evaluation for distributed control systems using dioid
Louis Bal Dit Sollier1, Alain Ourghanlian2, Saïd Amari3
1LURPA, ENS Paris-Saclay, 4 ave. des Sciences, 91190 Gif-sur-Yvette, France; PRISME, EDF Research and Development, 6 quai Watier, 78401 Chatou Cedex, France.
ISA Transactions
|November 8, 2024
Summary
This study provides a method to calculate the maximum response time for Distributed Control Systems (DCS) using Timed Event Graphs (TEGs). The approach ensures system safety by computing a reliable upper bound for response times.
Area of Science:
- Control Systems Engineering
- Real-Time Systems Analysis
- Discrete Event Systems
Background:
- Distributed Control Systems (DCS) require accurate response time analysis for safety and efficiency.
- Existing methods may not adequately address the complexities of asynchronous events and batching in DCS.
Purpose of the Study:
- To develop a novel approach for computing a safe upper bound of the response time in DCS.
- To provide a robust method applicable to Timed Event Graphs (TEGs) with asynchronous links.
Main Methods:
- Utilized algebraic representations based on the M_in_ax dioid for time/event dynamics.
- Introduced scalers and operators to handle event batching and multiplication.
- Calculated system trajectories and transfer functions under deterministic and worst-case hypotheses.
Main Results:
- Computed the worst-case delays induced by the TEG model.
- Successfully established a safe upper bound for the response time of the DCS.
- Validated the proposed method with numerical applications and experimental data.
Conclusions:
- The developed method offers a modular and automatable way to determine DCS response time upper bounds.
- The approach is versatile and can be applied to any DCS modeled using TEGs.
- This facilitates enhanced safety and performance analysis in complex control systems.
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