At the 2018 Ovation Users’ Group Conference, Emerson’s James Thompson and Sheldon Willis provided an update on embedded simulation in the Ovation distributed control system. Ovation-based high-fidelity simulator models are embedded directly into virtual Ovation controllers as compared with the more traditional approach with third-party models that run in separate hardware. This single platform for simulation and control provides familiarity for system users with operation, configuration and maintenance activities.
Sheldon opened describing two types of simulators—training and engineering. Training employs simple and enhanced tiebacks of the I/O signals up to high fidelity models which simulate the process response to the control strategies. Engineering simulators can provide process design validation, controls validations and more.
Benefits of simulation include testing and tuning the controls offline, test new control scenarios, train operations and maintenance personnel, and troubleshoot process problems to help identify root causes.
Virtual controllers run in Windows-based PCs simulate the actual Ovation controllers to provide a similar experience to the actual system and attached controller and I/O hardware. Here’s a typical layout:
For training simulators, an instructor station gives ways to run exercises to train operators to manipulate the simulation and score the responses.
James described some high-fidelity, first principles models for equipment such as pumps, fluid streams, mechanical connections between motors and equipment such as fans, valves, etc. Mathematical models are developed based on how the equipment operates in real life. A simulation model library includes 174 unique model algorithms in 8 suites. These include base, electrical, turbine, combined cycle, boiler, balance of plant, flue gas desulfurization (FGD) and selective catalytic reduction (SCR).
The integrated simulation has online and simulator configuration in one database. When changed are made, they are aimed at either the online or simulator area. This allows testing to be performed in the simulator area before downloading to the online configuration. A reconciliation capability synchronizes the simulation with the online configuration which keeps the simulator up to date.
Sheldon and James concluded that this embedded simulation approach simplifies training, controls checkout & tuning, plant procedure development & optimization, reduces risk, and enhances the plant’s overall approach to safety.
