Node Ordering Scheme of Large Scale Power Systems Using Sparse Matrix Techniques

Abstract

Power flow is the basic tool for power system analysis which reveals the system operation in a steadystate mode for evaluation of the power system planning and operations. The accuracy, simulation time, computer storage size and convergence of any model used depend largely on the size of the bus admittance matrix of the system under study. This paper, therefore, presents the study of the bus admittance matrix of the different systems with sparse techniques. And also analyze the number of zeros and non-zeros element in the different systems with minimum ordering schemes. The proposed method is validated using a 5-bus, 30-bus, 118-bus and 300-bus systems. The results are presented in graphical form and discussed. The sparse Matrix techniques show that as the system is increasing in size, the percentage of stored bus admittance elements decreases and changing the order of the nodes gives more impact on the size of the system. Thus, an appreciable reduction in the computer memory required to store the bus admittance matrix and in turn reduces the overall simulation time.