I am looking for help to build a dynamic simulation of a boiler drum level. Issues that are important to capture include:
- inverse response of the level to changes in drum pressure, steam flow, boiler feedwater flow and boiler firing.
- difference in behaviour between small and large disturbance conditions.
- level measurement errors as a function of pressure.
I am evaluating the drum level control tuning of different boilers in an oil refinery. One big problem is that the dynamic response of the steam drum levels on small and large disturbances could be very different. We want to know how optimum the tuning is under large steam upset conditions, and this is for obvious reasons difficult to test on a real plant. I want to build a useful simulation to tune the PID controllers and to test other rule and model based algorithms so that we can have confidence in the performance of the boiler drum level controllers.
As an example if what I want to do, I recently build a very simple yet very useful simulation of a compressor anti-surge control system and this allowed us to have enough confidence in that specific, previously suspect, control scheme. I am a bit unsure how to capture the shrink and swell effects of the boiler drum level adequately, especially the difference in behaviour under small and large upset conditions, to allow me to do the same for the boiler drum level applications.
I will appreciate help on this appliction.
Pieter Steenekamp