A New Pseudo Load Profile Determination Approach in Low Voltage Distribution Networks

Abstract

Low voltage (LV) state estimation in distribution networks mainly relies on pseudo measurements because the real-time monitoring is impossible for all customers. This paper presents a new method to determine the pseudo load profiles (PLPs) of customers with small consumptions connected to the LV distribution networks. This method is comprised of two stages. First, a new frequency-based clustering algorithm is proposed to extract the essential load patterns of limited number of customers who are equipped by smart meters and are called as sample customers. The superior performance of the proposed clustering algorithm is also shown in comparison with three of the most widely used clustering methods: k-means, self-organizing maps and hierarchical algorithms. In the second stage, a new approach is proposed to estimate the daily energy consumptions two weeks ahead for other customers who are not equipped by smart meters by using their previous billing cycle energy consumptions and the load data of sample customers. The PLP of a customer is obtained by multiplying the estimated daily energy consumption by the corresponding normalized load pattern. Studies have been conducted on the data of a real distribution system to verify the proposed method and to show its application for the PLP estimation of distribution networks.