To investigate the dynamic characteristics of water level in utility boiler drums and keep the drum water level within its normal range

this paper established the system dynamic model for the drum water level by using the principle of system dynamics and taking causal loop diagrams and stock and flow diagrams as its carriers

based on the mass and energy conservation laws

from the working mechanism of the system based on the macroscopic angle.Using the operation data of Hebei Qingyuan Power Plant 300 MW subcritical drum boiler

the simulation was carried out in Vensim PLE environment.In addition

the system dynamic model was compared with the conventional model.The results show that the simulation results by the system dynamic model agree well with that of the conventional model

verifying the correctness of the proposed model.The system dynamic model can well represent the matter and energy relations within the system

and has appropriate complexity and clear structure.