LOADING LIMIT OF AN EHV POWER SYSTEM CONSIDERING VOLTAGE STABILITY USING CATASTROPHE THEORY

Electrical Engineering Dept. Suez Canal University, Port-Said, Egypt

Steady state voltage profile and line loading limit of EHV power system has been analytically

investigated from the view point of voltage instability using the Catastrophe theory. The system

voltage equations are formed in a lossless frame, the basic expressions for the power transfer limit

at critical magnitude of receiving end voltage and power angle have also developed to highlight the

implication of reactive power loading as well as power factor at the receiving end bus in a

longitudinal power line. Catastrophe theory gives, among other things, a qualitative description of

how sudden effects can arise from the smooth change of parameters in a system , and has been

applied by the author to the study of steady state and transient stability of power system. Their

analysis is with respect to angle instability. But the instability may be manifested in many different

ways, depending upon the character and configuration of the system and also upon its operating

mode. For example, in some cases in which voltage instability has been approached with no

immediate prospect of angle instability. This is particularly true in a longitudinal power line, where

the generation is away from the load center. This aspect is analytically verified in this paper.