An engineer is responsible for the control design of a new plant. His DeltaV control system will not be shipped for another month, but he has installed DeltaV Simulate on his computer. One loop that is critical to plant operations uses a feedforward signal from a feed stream that is not used for some products. Under the condition of no flow, the input signal can have a BAD status. It is important in his design of the control system to understand how the PID behaves under this condition.
To learn more about how the PID operates under such a condition, the engineer assigns the associated control module to his computer, downloads, and then, using Control Studio's online view, examines the PID and feedforward signal provided by an AI block. Using the SIMULATE parameter of the input blocks to the PID, he establishes a normal operating condition. Then, by changing the SIMULATE parameter status of the feedforward input to BAD and back to GOOD, he observes that the operation of the PID is not disrupted by the status going BAD. Knowing that the DeltaV PID addresses this situation, the engineer is able to finalize the design of this critical control loop.
Plant production is limited by feedstock processing. To determine if proposed process design changes will allow greater throughput, a high-fidelity dynamic simulation of the process is constructed using a process simulation package. The engineer responsible for resolving the production limitation must determine whether the product specifications can be met using the original control strategy. To examine the control system's response to changes in feedstock, the engineer installs DeltaV Simulate onto his development computer with the process simulation.
By assigning the current DeltaV control strategy used in the plant to his computer and configuring the process simulation package to access the control I/O blocks, the engineer is able to simulate the dynamic response of his plant with the current control strategy. By introducing the expected feedstock changes into the process simulation, he determines that the current control strategy does a good job. However, the tuning of some loops will need to be changed. Using Tune With InSight in the DeltaV Simulate environment with the process simulation package providing the process simulation, he retunes the simulated control loops and establishes what the best tuning will be for the new process design.