The invention discloses a method for evaluating the
electric power system risk based on fault pre-scanning. The method comprises the steps that firstly, according to the current structure of an
electric power system and a planning scheme, a corresponding planning scheme model is established; secondly, based on device data and a
power grid structure, predicted faults and the possibility of the predicated faults of a
power grid are analyzed, and then a pre-scanning fault set is formed; thirdly, through the risk state based on direct-current
power flow, screening and ordering are conducted on the predicated fault set, so that a fault state
list is formed; fourthly, all
power flow corresponding to the faults in the
list is worked out, and for the fault with the
power flow out of range, the consequence of the fault is
load loss; fifthly, according to the
load loss of the fault states and the possibility of the fault states, the
system risk indicator is worked out; sixthly, according to the
system risk indicator, the system weak link is found out. By the adoption of the method for the evaluating
electric power system risk based on fault pre-scanning, analysis of all the fault sates in the fault set through alternating-current power flow is avoided, so that the calculation amount of follow-up alternating-current power flow analysis and
risk indicator processing is greatly reduced, and a large
mount of calculation time is saved.