Controls for Combustion Optimization Dr. Martin Bergemann Dipl.-Ing. Harald Petermann February 27 th 2014 Gas Sensor Workshop 1
February 27 th 2014 Gas Sensor Workshop 2
The Afecor is the association of the leading European controls manufacturers has been established 1963 works to influence directives and standards ensuring safe, efficient and environment friendly use of primary energy sources. holds seminars to exchange information between experts and stakeholders on legislation, technologies and market development www.afecor.org February 27 th 2014 Gas Sensor Workshop 3
Content Standards Sensor Types System Examples Safety Considerations Conclusions February 27 th 2014 Gas Sensor Workshop 4
Combustion Control Relevant Standards Standards of CEN TC 58 "Safety and control devices for burners and appliances burning gaseous or liquid fuels EN 13611 Safety and control devices for gas burners and gas burning appliances General requirements EN 14459 Safety and control devices for burners and appliances burning gaseous or liquid fuels Control functions in electronic systems Methods for classification and assessment; EN 298 Automatic burner control systems for burners and appliances burning gaseous or liquid fuels EN 12067-2 Gas/air ratio controls for gas burners and gas burning appliances. Part 2: Electronic types EN 16340 Combustion product sensing devices for gas burners and gas burning appliances; EN 1854 Pressure sensing devices for gas burners and gas burning appliances February 27 th 2014 Industrieforum GAT 5
Sensor Types Ionisation Temperature Flue Gas O 2,CO + no extra sensor + low cost - contamination - drift + simple + moderate cost - accuracy (method) - implementation + accurate + wide range - high cost - aux. heating February 27 th 2014 Gas Sensor Workshop 6
Zirconium Oxide Sensor Source: Lamtec February 27 th 2014 Gas Sensor Workshop 7
Combustion Control Residential Boiler Source: Siemens February 27 th 2014 Gas Sensor Workshop 8
Performance Example Residential Boiler Source: Viessmann February 27 th 2014 Gas Sensor Workshop 9
Oxygen Trim Control Commercial Dual Fuel Source: Siemens February 27 th 2014 Gas Sensor Workshop 10
Combustion Control Safety Considerations The adaptive combustion control system has to be integrated into the safety concept of the gas burning appliance If the sensor fails, the appliance has to return to a safe mode For ionisation sensors a failure of the sensor leads to a safety-shutdown. Sensor deterioration is being compensated for as a matter of calibration cycles For flue gas sensors which are not fail safe in itself or being supervised by other means, only a limited trim of the lambda value is possible February 27 th 2014 Gas Sensor Workshop 11
Conclusion Combustion optimization solutions do exist for residential and commercial applications Implementation of systems integrated into the combustion chamber often requires a lot of engineering, the cost of which often offsets the low price of the sensors Systems measuring the flue will mostly do minor adjustments for safety reasons Sensor development is underway so that less expensive solutions will become available in the next few years February 27 th 2014 Gas Sensor Workshop 12