An integration framework of the distribution network cyber-physical system (CPS) is established in this paper. Firstly, the CPS model of the distribution substation is constructed according to the IEC 61850 standard and the interaction between the information layer and the physical layer is analyzed. Secondly, different types of physical layer fault propagation scenarios triggered by information elements are enumerated, classified and defined under the consideration of the abnormal operation conditions such as the delay, malfunction and refusal of cyber elements. By calculating the probability of different physical layer fault propagation scenarios during the fault clearing process, the coupling effect of distribution network information elements on the physical layer is quantitatively evaluated. A 10 kV distribution network feeder system in a certain area is taken as an example to carry out the calculation and analysis of the fault scenario. The failure of cyber elements expand the scope of physical layer failures, among which the communication link failure of the switch has the most significant influence.