Improving the Accuracy of the State Estimation Algorithm in the Power System Based on the Location of PMUs and Voltage Angle Relationships

Abstract

In order to make better use of the power system, monitoring network mode variables is of particular importance, because these variables play an effective role in improving economic efficiency, improving network reliability and improving the ability to analyze the status of the system. For this purpose, state estimation algorithms have been used with the aim of accurately estimating state variables with finite measurements. Since today's measuring devices such as PMUs, in addition to measuring electrical quantities, are able to measure the voltage angle of the buses, this paper presents a method to make more accurate estimates. Obtained from all network variables. The proposed algorithm, while determining the number of measuring devices (PMU), determines their suitable location in such a way that using their information, the most accurate estimates can be obtained to obtain state variables and quantities. Electric provided. Increasing the accuracy of the calculations by using the derivative equations of the voltage-angle equations of the buses coincides with the state estimation relations. Finally, the state estimation calculations were performed by the weighted least squares (WLS) method. The calculations were performed on the IEEE 14 bus network using MATLAB and MATPOWR software. The results show that the proposed method has been successful in increasing the accuracy of estimating state variables and reducing the number of PMUs and proper placement of PMUs.