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An economical load flow study is needed for automatic distribution network for designing, operation, economic dispatch, stability analysis & contingency analysis. This paper introduces an easy three phase unbalanced load flow technique which will handle unbalanced radial secondary distribution networks. The proposed technique uses the modified Forward-Backward technique that addresses the constant-power, constant -impedance and constant-current load models, regulators, transformers and switches. It solves an easy algebraic algorithmic expression of voltage magnitude. The suggested technique having better convergence rate and execution time is also less for any type of load model, size of the network, and resistance to reactance ratio of feeders.19-bus and 25 bus URDNs results are in agreement with the literature and show that the suggested technique is efficient and reliable.
radial distribution networks, load flow, modified forward-backward based technique
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