Station boiler air preheater hot spot detecting method based on analog computation of rotor temperature field

The invention discloses a power station boiler air preheater heat spot detecting method based on rotor temperature field analog computation. The method is implemented according to the following steps: parameters of the air preheater needing to be monitored are determined and a temperature reference value is set; various parameters are collected in real time and the obtained parameters are input into a computation module; a boundary temperature value is initialized, and boundary conditions are determined; the temperature of the section, the interior of the sub-bin and a fluid and a heating surface on the exit boundary is obtained by using a difference equation; if temperature error obtained before and after an interactive process is in accordance with the set temperature reference value requirement, the computation is over, otherwise, the boundary temperature value is renewed to carry out interaction again. When fault happens to an infrared heat spot sensor or an executing mechanism of an existing heat spot detecting system, the system sends out a switching command, by using the temperature field parameters obtained by the analog computation of the method of the invention as the reference value for control, the reliability of the air preheater heat spot detector is improved and the safe and stable operation of the detecting system is guaranteed.