Voltage stability analysis for radial distribution networks with and without compensation

In this paper, presents a method for voltage stability analysis for radial distribution networks. A new voltage stability index is proposed for identifying the node, which is most sensitive to voltage collapse. Four types of load modelling, namely the constant power, constant current, constant impedance and composite load models are considered for the purpose of voltage stability analysis and a comparative analysis is presented.

In addition with, shunt capacitors compensation is used in the same network and the whole process of voltage stability analysis is repeated for the four different types of load. It is seen that with shunt compensation, the voltage stability index and hence the voltage at the instant of collapse has improved to a great extent. It is found that for above two studies, voltage collapse occurs at a particular node implying that the phenomenon of voltage collapse at a node depends mainly on the critical loading conditions of that node. It is also seen that the stability index of a particular node varies almost linearly with the change in load.