Air Preheater Hot Spots Detection System Based On Multi-Sensor Information Fusion

Power boiler air preheater hot spots detection system is a indispensable installation which are applied in power plant largely. It fires easily for air preheater in practice application situation because of its characteristic. It results tremendous economic loss and even personnel casualty. So it is necessary for power plant to detect hot spots in air preheater. From simulations and data of fire site, most air preheater fire often appear when boiler is started in cool state and standby which fuels of insufficient combustion coagulate and congregate on the parts of air preheater. When the temperature of smoke inpouring air preheater increases, aggregate fuels and sediments will combust in stated temperature conditions. It is called the second combustion of air preheater. It is very important problem how to detect aggregate fuels and sediments temperature on air preheater parts surface effectively in order to prevent air preheater from fire.The article presents air preheater hot spots detection system based on multisensor fusion. Hardware design of the system and communication between main computer and PLC based on Modbus Protocol have been completed as well as judging methods of fire based on multisensor fusion. It is shown that this detection system is practicable and effective after applications on more than 10 power plants.