jblc
Mechanical
- Apr 2, 2009
- 24
I'm curious about your preferred way to analyze and develop a hybrid feedback control system, where the controller is actually made up of a few unconnected controllers that you switch between. The loop is a standard feedback loop: SP --> SPerror --> controller --> plant --> PV, and PV is fed back to get SPerror.
As an example, say you control Valve 1 a certain way if the SP error is small, and control Valve 2 a certain different way if the SP error is larger. Assume each valve has a different risetime and dead-time.
The controller in this case is a hybrid control made up of two controllers that control two plants (valves), and is nonlinear in nature.
How do you go about analyzing performance for such a system? Clearly it's east to analyze each loop independently (the Valve 1 control+plant loop, and the Valve 2 control+plant loop), but that doesn't characterize both together...
Independent loop analysis is especially not useful if trying to model the system with an input disturbance, since analyzing each loop independently wouldn't capture how the actual hybrid system would performs with both plants.
As an example, say you control Valve 1 a certain way if the SP error is small, and control Valve 2 a certain different way if the SP error is larger. Assume each valve has a different risetime and dead-time.
The controller in this case is a hybrid control made up of two controllers that control two plants (valves), and is nonlinear in nature.
How do you go about analyzing performance for such a system? Clearly it's east to analyze each loop independently (the Valve 1 control+plant loop, and the Valve 2 control+plant loop), but that doesn't characterize both together...
Independent loop analysis is especially not useful if trying to model the system with an input disturbance, since analyzing each loop independently wouldn't capture how the actual hybrid system would performs with both plants.