Harmonic state estimation: a method for remote harmonic assessment in a deregulated utility network

In a deregulated electricity industry, new concerns have emerged regarding the quality of power supply as each company involved will focus on its own objectives and interest. One of the main concerns regarding the quality of power supply is the harmonic pollution. Several harmonic state estimation (HSE) techniques have been proposed for harmonic source identification. This paper presents a new HSE algorithm, which is based on singular value decomposition (SVD) method. The algorithm does not require the whole network system to be observable prior to estimation, it can give a solution even if the system under consideration is partially observable. The reduced primary AC system for the whole South Island of New Zealand, which consists of 15 main substations and more than 100 nodes is used as the test network for the validation of the new HSE algorithm. The new HSE algorithm can be used by the ISO (independent system operator) as well as distribution companies to monitor the harmonic condition and identify harmonic sources for different parts of the network.