Posted by Gburns on November 05, 2001 at 06:12:58:
In Reply to: Black Box Intelligent Controller Concept posted by Stephen Rogers on November 05, 2001 at 02:34:31:
1. For industrial boilers the type of controls are as varied as the industries they serve. Most are cross limited tieback type control schemes with fuel input is measured in a variety of ways including actual fuel measurement, inferring BTU input based on steam output, calculating heat input based on the amount of air consumed (air in - excess air out). Most plants simply have air flow based on fuel input with O2 trim. It is usually an operator function to monitor exit gas temps, emissions and other performance factors to identify problems.
2. Most control systems do not show a decline in boiler performance, however, some PC based energy management systems do monitor boiler performance to determine which equipment is operating a the highest efficiency and lowest cost so that the entire plant can be optimized economically. Also, several utilities have been incorporating nueral networks to monitor boiler performance in regards to optimizing the boiler while keeping it in compliance environmentally. These would probably be very close to what you are talking about. I am familiar with two companies Pegasus and Pavillion Technologies which market this type software.
3. Obviously some companies are attempting to do this, however, there must be a significant return on investment or proof that is will keep a plant in compliance environmentally to really have a market. I do know that some utilities are going with the nueral networks but the return does not appear to be there yet for industrial customers.
Most industrial customers want a return on investment of 2 years to release money to proceed.
4. Most modern plants will have adequate information to run performance data on. The only problem arises in maintaining that instrumentation to the standards required by advanced controls (more money). Using a predictive model you may be able to determine if instrumentation needs attention and to some degree even compensate for it. But in the end the annual amount that a plant spends on instrumentation maintenance will go up. How to get the information to a PC depends on the type control system being used. Pretty much all DCS control systems today will be able to interface with a PC through some sort of link.
5. Any "Black Box" type control scheme would have to be extremely robust and require very little operator interface other than turning it on and off. Most operators are not going to be up to speed on these control methods and if problems arise with the controls, they will be turned off and may never be turned back on. I been to many plants operating in manual only to find a very adequate control design programmed into the plant's DCS. Basically shut off due to a lack of understanding of how the controls work.
Good luck
: I am part of a group of Final Year Masters students in
: Electrical and Electronic Engineering at Queens University Belfast. We are beginning an industrial project involving the control of boilers particularly large industrial boilers found in factories throughout the world. We aim to design an intelligent device which will be placed alongside the boiler system and will create an idealized model of the system and
: monitor and assess the performance of the boiler in comparison with the model. It could then be used to optimize the boiler i.e. control the inputs to maximise the output, as a warning when there is a problem with the boiler and as a general indicator of when maintenance is needed due to significant performance degradation over time. We need information regarding the present control of boilers, any help you can give regarding the following questions would be greatly appreciated:
: 1. What control is built in to the boilers at present?
: 2. Does it indicate a gradual decline in performance?
: 3. Would an intelligent device that learnt the system on-line and built up an ideal model of the boiler for comparison in performance be useful for:
: a) optimizing the output of the boiler and/or
: b) giving an indication when maintainance is needed?
: 4. How could we get infomation from the boiler regarding the temperature, pressure, input flow rates of oil, output etc? Is this information already available on the boilers?
: 5. Is there any other way the control of the boiler could be improved?
: Please send us any other contacts or information that could be useful in this area,
: Thanks for your time,