Power system external network equivalent model automatic forming method

The invention discloses a WARD equivalent expansion method based on sensibility in the electric power dispatching automation domain, which comprises the following steps: conveying real-time data from lower level electric network dispatching center to higher level electric network dispatching center; doing total network current calculation; calculating real-time external net equivalent model for each lower level electric network; sending the external net equivalent model to the lower level electric network dispatching center through remote data net; combining the received external net equivalent model of lower level electric network dispatching center self electric network with self interior electric network detail model; doing network analytic calculation of lower level electric network energy management system and artificial training system, wherein the system is periodic starting or automatic starting when the network structure changes. The invention adapts expansion WARD equivalent method of keeping buffer net, which is automatic formation through artificial assignment or sensitivity method.