Which term describes the strategy that utilizes two controllers in an advanced control configuration?

The term that describes the strategy utilizing two controllers in an advanced control configuration is cascade control. Cascade control involves a primary controller that sets the setpoint for a secondary controller, allowing for more precise control of a process. In this setup, the primary controller manages a broader aspect of the system, while the secondary controller fine-tunes a more specific element. This hierarchical approach enhances the system's overall response and stability, particularly in processes where there are measurable delays or disturbances.

For example, in a temperature control system where a furnace is regulated, the main controller could adjust the overall temperature setpoint, while a secondary controller could specifically manage the flow rate of the fuel or coolant to achieve optimal thermal performance. This layered technique allows for more responsive control and minimizes the chances of overshoot or oscillation in the system.

The other terms, while related to control strategies, do not specifically refer to the dual-controller approach that is characteristic of cascade control. Feedforward control anticipates disturbances and adjusts inputs accordingly without waiting for measured feedback. Feedback control relies on the difference between a desired setpoint and the actual output to make adjustments, and integral control focuses primarily on eliminating accumulated past errors by adjusting the control output based on the integral of the error over time.