Study of the effect of X/R ratio of lines on voltage stability

A voltage stability problem mainly occurs in heavily stressed systems. The maximum power that can be delivered to loads and relationship between load power and network voltage are the two basic properties that require thorough analysis. In much of the analysis reported on voltage stability the study of effect of variation of X/R ratio of transmission line on receiving end voltage is not explicitly portrayed. This paper develops a procedure to investigate the effect of variation of active load, reactive load and X/R ratio of line on the terminal voltage (receiving end voltage) of a radial line. A normalized approach using the maximum power in a resistive tie (X/R=0) as the base power enables deriving P-V curves with X/R ratio and load power factor as parameters.