Optimal allocation of voltage sag monitoring based on exposed area analysis

The optimal allocation of voltage sag monitoring buses is proposed based on the analysis of voltage sag exposed areas,which takes the least monitoring buses as its objective and the voltage sag observability of the sensitive load nodes over network as its constraint,and applies ILP and MATLAB programming to allocate the voltage sag monitoring buses.The fact that single node fault may cause the voltage sags of other nodes is considered during the calculation of exposed area matrix.The proposed method is applied to IEEE 39-bus system and the minimum monitoring buses are determined to ensure the observability of the sensitive load nodes over network.