Step voltage regulators (SVRs) located at medium-voltage radial feeders are often part of many strategies to mitigate interconnection impacts of distributed generation (DG) units. However, conventional methods for rapid analysis of characteristic parameters of active distribution networks do not usually factor the effect of SVR tap operations in their calculations. This dissertation proposes a novel analytical formulation for the assessment of the influence of such devices, based on mathematical modification of traditional expressions found in the literature. The developed theoretical framework concerns voltage variation along the feeder, requirement of reactive power, electrical losses and DG hosting capacity. The proposed approach is validated via comparative studies conducted in a simple test-system, as well as in a long 34.5 kV rural feeder that contains two cascaded SVRs along with a high penetration DG at its far end. The Open Distribution Simulator Software (OpenDSS) is used for modelling, traditional load flow simulations and quasi-static time series analyses. Results show the merits of the developed formulation in correctly estimating active distribution networks’ parameters in the presence of SVRs, which marks an improvement over conventional tools for DG integration preliminary studies.
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