Optimal Phasor Measurement Unit Placement for Monitoring of PEA Bowin Power

Abstract

This paper presents an optimal method of Phasor Measurement Unit (PMU) placement in Bowin area distribution grid of the Provincial Electricity Authority (PEA) using the Improved Greedy Method (IGM) in order to achieve a minimum number of PMUs for complete observability of all bus voltages. The proposed method introduces the criteria of bus selection for PMU placement, regarding a number of branches connected to the selected bus as well as the length of those branches. Subsequently, the mismatches of the observed voltages resulted from the proposed method are compared with those resulted from the Depth First Search (DFS) using the Power System Analysis Toolbox (PSAT) and the original Greedy method (GDY) to reveal the effectiveness of the proposed placement methods. For the DFS and GDY methods, a bus with the highest number of connected branches is initially selected as the first PMU bus. However, if there is more than one bus, the first PMU bus will be randomly selected from those qualified. On the other hand, the PMU bus firstly selected by the IGM must have the highest number of connected branches as well as the minimum total distance or total impedance of all observable buses. The findings resulted from the IGM are the optimal PMU placement with the total distance of the connected branches less than the other methods, especially for, large-scale networks. According to the comparison results among the DFS, GDY and IGM, the mean absolute error (MAE) of the angle and the magnitude voltage of all buses resulted from the IGM is the lowest for a wide range of load conditions, while the MAE resulted from the DFS is the highest.