HELM – a new method of calculating power flows in power grids
Main Article Content
Abstract
Numerical algorithms based on iterative techniques have been used for a long time to analyse power flows in power systems. However, these methods do not guarantee that the commenced iterative process will always converge. At the same time, power flow equations have many solutions, and only one of them corresponds to the actual state of the concerned power system’s operation. HELM (Holomorphic Embedding Load-Flow Method) was developed to overcome these limitations. It employs complex analysis techniques. Its most important feature is that if a solution exists, it corresponds to the actual state of the system’s operation. However, where no solution exists, it unambiguously warns that there will be a voltage avalanche (blackout). The method’s very important characteristic is that it is recurrent and not iterative like the classical algorithms. Its potential and the options of its use in real-time applications for many operations related to power system performance have been demonstrated so far in a few publications. The paper presents the main assumptions of the HELM method and how basic components of the power system model can be mapped using the complex analysis technique. It also compares HELM calculations with those made with classical iterative methods.
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References
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