In order to effectively curb accidents，strengthen the guidance and support role of safety theory in power safety production，and overcome the mismatch between foreign theories and existing safety theory models that cannot meet the actual needs of complex power safety production，local characteristic power safety production management theories and models were constructed. Based on various advanced causal chains，causes of accidental energy release accidents，nuclear power protection barriers，and 4M barrier theories in China and abroad，combined with the objective reality of the safety production site of the power generation enterprise of CHN Energy Group and years of risk control experience，the reverse thinking of accidents (accident causes) and the positive thinking of risk pre-control (barrier control) were combined to propose the 4M barrier theory of machine & material，man，medium，and management in safety management of power generation enterprises. Through dynamic modeling，the internal accident evolution roots and prevention and control laws were analyzed，and the internal logical relationships of each element were sorted out. The results show that this theoretical model can provide a relatively systematic and new risk pre-control concept and methodology for power generation enterprises to establish a sound safety production risk management system by clarifying the risk and its barrier control objects and analyzing the accident development process and its causes.

power generation enterprises  /  risk control  /  machine & material，man，medium，management (4M) barrier theory; machine  /  machine，man，medium，and management  /  dynamic modeling