Power Distribution Grid Reliability Assessment Considering Protection and Control Devices’ Optimal Post-Fault Operation

The reliability level of the distribution network is a judgment tool of the grid and protection design quality, the effectiveness of the fault management unit, and customers’ satisfaction. In this paper, a new approach is presented to evaluate common reliability indices namely ENS, SAIDI, SAIFI, MAIFIe, etc., while reliability improvement via optimal post-fault restoration describes the coordinated operation of various protection and control devices in temporary and permanent fault event conditions. Customers’ outage times are calculated considering different switching operation times to capture manual operation issues, e.g., traffic level, geographical issues, fuse replacements, etc. The optimal service restoration scheme being formulated in a mixed-integer linear programming (MILP) fashion is constrained to network technical limitations, e.g., line thermal capacity, load points voltage level, DG units’ parameters, and island operation. Performance of the proposed framework is verified in IEEE ۳۳-bus test system.

Keywords:

Reliability indices , service restoration , protection devices , isolating switches , distribution system