Investigation of voltage stability in power system using the genetic algorithm

INVESTIGATION OF VOLTAGE STABILITY IN POWER SYSTEMSUSING THE GENETIC ALGORITHMAli ÖztürkSUMMARYKey Words : Power Systems, Voltage Stability, Genetic AlgorithmIncrement of power demand of the consumers in the electric power systems and as a result ofthis increasing demand, difficulties of construction of the new energy transmission systemhave shown the importance of determination of the critical values of power system voltagestability subject. In case of being late in interference when critical values have beingexceeded, in the first step voltage instability then in the folloving step voltage collapse occurs.Recently, a major incerement on the news related to voltage collapse come from variousregion of the world has being observed. In the case of voltage collapse, occurence ofespecially economical great damage in the system for rehabilitation has obliged thecalculation of critical values formerly and making improvements if it is necessary.In this study, the genetic algorithm method as a new method for calculation of the criticalvalues of the power system is used. Firstly, in the various operation conditions, as an examplecritical values of two-buses power system are determined using conventional method andgenetic algorithm method. Conventional methods are considered as a critical valueformulations method derived from the case of system jacobien matrix produces singularsolution and P-V curve method that shows the variation of active power supplied from end ofthe line versus amplitude of end-line voltage. In the next step of the study, critical values ofexemplary N-buses power systems are determined using power flow programme, busreduction method and the genetic algorithm method for various operation conditions. It isstudied to determine the optimum condition in terms of voltage stability with determining thecritical values of power system for various operation condition.Similarity of the results obtained from the studies of determination of critical values of bothtwo-buses and N-buses power system using conventional methods and the genetic algorithmand also the potential of the genetic algorithm method is showed in the calculation of thecritical values of voltage stability. The results show it is critical values are determined easilyusing genetic algoritm.