Voltage Stability Assessment by the Modal Analysis and the Load-Flow Linear Sensitivity Techniques

In this paper the modal analysis and load-flow linear sensitivity techniques are investigated for voltage stability evaluation. Analysis modal is an elegant and very well accepted method. However, in this paper it is shown that the conclusions reached with this method are almost the same by applying the load-flow linear sensitivity technique. In order to show this hypothesis both methods are applied to the IEEE 14 and 30 bus systems. Main advantages and drawbacks of both techniques are pointed out in the paper.