Given the importance of load flow analysis for successful planning and operation of power systems, there is an increasing need for power flow methods that would give accurate results and also be devoid of convergence issues that are typical of the classical iterative methods. This has given rise to the innovative Holomorphic Embedding Load-flow Method (HELM) that is non-iterative and could find a solution when it exists and indicate when there is no solution, such as in the case of voltage collapse. Documented evidence over the years shows that the NRLM is the most commonly used iterative method due to its superior advantages, therefore, it is chosen for the comparison. The objective of this paper is to weigh up the merits of HELM over the Newton-Raphson load flow method (NRLM) based on information obtained from actual applications and since HELM is not found as one of the methods previously applied for the analysis of the Nigerian network, the behaviour of the system with HELM is explored. At the end of the solution process, HELM was found to be 4.33% faster than the NRLM for the IEEE 4-bus system and 19.31% faster when applied to the Nigerian 330kV network; this validates a major advantage of HELM over iterative solutions. Secondly, though special software was produced for HELM and might be the best for it, an attempt was made to develop a MATLAB program since the software is easily accessible. However, more work is required in the programming to successfully analyse large or ill-conditioned systems.
Key words: approximants, convergence, holomorphicity, Jacobian
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