Gain Scheduling - Thought Leadership with Ian Collins | Video

Ian Collins, Product Manager at West Control Solutions talks about the Gain Scheduling feature found in the PRO-EC44 controller.

Transcript

Controllers are generally designed for the control of linear process variables, however in reality the characteristics of the application can change within a process. In a control system this can be changed in the thermal characteristics over a wide operational range of an oven.

The result, of exothermic reaction or a product changing state from solid to liquid, there are many other examples. The result is the application cannot be controlled as required over the complete operating range.

Gain scheduling allows the controller to compensate for this type of variation.

Gain scheduling is a method of splitting the total operating range into smaller bands with similar thermal behavior, each having their own PID or gain settings. As a setpoint or process value falls within these bands, the appropriate PID set is automatically called meaning the control parameters are specific to the operating range. These smaller bands with common behavior are then tuned individually to achieve optimized control performance.

Similarly, this method can be applied to other process variables, such as flow, which is a specific example or a nonlinear variable.

When passing from one temperature band to the next, as disturbance can occur, as the PID settings switch. It’s important to ensure your controller supports bump less transfer to ensure the system will transition to the new PID settings with no fluctuation.

Some controllers also support the manual selection of PID set which can be selected prior to running the process, this is useful when running products with different characteristics.

The result, is better control performance over the full operating range of the process. Controllers use such as overshoot and temperature fluctuation are reduced meaning efficiency is improved and waste minimized.

For more information, visit our website on www.west-cs.com