Evaluation of voltage stability applying N-1 criterion, Albanian power system case study

摘要

The paper represents the result obtain by applying the N-1 criterion in the voltage stability analysis. The modal analysis is used to identify the potential voltage collapse situation of the system. The magnitude of each minimum eigenvalue provides a measure to know how close the system is to voltage collapse, while the branch participation factors indicate, for each mode, which branches consume the most reactive power in response to an incremental change in reactive load. Branches with high participations are either weak links or are heavily loaded. Bus participation factors identify the weakest areas in terms of voltage. The Branch participations and Bus participation factors are used for contingency selection and for identifying countermeasures to solve voltage stability problems. The minimum eigenvalue and its highest branch participation factors to identify the weakest links is used. The obtained result gives very important information in order to identify the most critical element (branch) of the network, for contingency selection to be evaluated applying the N-1 criterion and the load shedding strategy to solve voltage stability problems.