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Smart grid activities are increasing the implementation of automated sectionalizing devices on distribution systems. Most methods for identifying the optimal distribution automation allocation (DAA) utilize general cost functions to account for the monetary impact of outages. Although these methods minimize lifetime reliability costs, they do not necessarily align with methods utilized by utility commissions and utility companies to restore power. Existing DAA approaches minimize strictly for outage, installation, and maintenance lifetime costs; however, during an outage a utility is more focused on minimizing “customer minutes interrupted” (CMI's). Most methods specifically ignore CMI's and assume utilities can address them within their generic cost function. The approach described within this manuscript identifies optimal DAA by minimizing the cost of CMI's after an outage. To align with accepted utility and commission practices for measuring the monetary impact of automated systems, the approach determines reliability costs by employing the “cost/CMI”. To account for cost variations between feeders, the approach applies the utility's expected/desired feeder values for SAIDI, CAIDI, and/or SAIFI to calculate avoided costs as defined by Berkeley National Laboratory's 2018 study. The method is easily employed with computational software. Evaluation and comparison of the approach is performed utilizing the Roy Billinton Test System. [ABSTRACT FROM AUTHOR]

The increasing implementation of nonlinear devices within residential homes may have a significant impact on feeder-level harmonic distortion. Within this paper, the long-term distortion possibilities on a distribution feeder due to a large number of residential customers producing harmonic currents near and above the IEEE Std. 519 limits are analyzed. To enhance the accuracy of the analysis, field measurements were utilized to define the relationship between the harmonic current produced by a single customer and their corresponding harmonic impedance. To evaluate how increases in harmonic demand over time will affect feeder-level harmonic voltage, the current injection method was applied to models of an actual 13.2-kV distribution feeder and an expanded version of the 4-kV IEEE 13 Node Test Feeder. Residential customers were represented by a Norton equivalent circuit with the developed harmonic impedance function. The evaluation results provide insight into future harmonic distortion levels while also establishing a structure for forecasting feeder-level harmonic distortion based upon system impedance and the existing levels of harmonic demand. [ABSTRACT FROM PUBLISHER]

Society's increased concern over green house gas emission and the reduced cost of electric vehicle technologies has increased the number of electric vehicles (EV) and plug-in hybrid vehicles on the road. Previous studies into the effects of electric vehicles on the electric system have focused on transmission, generation, and the loss of life of distribution transformers. This paper focuses specifically on identifying distribution transformers that are most susceptible to excessive loading due to the implementation of electric vehicles. The authors use a binomial probability model to calculate the probability that a specific distribution transformer will experience excessive loading. Variables to the function include the existing peak transformer demand, number of customers connected to the transformer, and the most common EV charger demand. Also included in the paper is an optimization approach that utilizes the results from the binomial function to determine the optimal replacement strategy to minimize replacement costs. An extension of the approach is also utilized to explore the effectiveness of EV targeted demand side management programs. The authors apply the described algorithms to 75 000 distributions transformers within a distribution system located in Denver, Colorado, USA. [ABSTRACT FROM PUBLISHER]

This paper discusses historical and technical events in the U.S. and Europe over the last few years that are aimed at modernizing the electric power grid. The U.S. federal government has ratified the “smart grid initiative” as the official policy for modernizing the electricity grid including unprecedented provisions for timely information and control options to consumers and deployment of “smart” technologies. European countries are unified in researching and developing related technologies through various structures supported by the European Union. This paper presents the development of smart grids and an analysis of the methodologies, milestones, and expected evolutions of grid technologies that will transform society in the near future. [ABSTRACT FROM AUTHOR]